Search Terms for HF Radio propagation

1. 24-hour HF propagation planner
 
A
2. A beginner's guide to HF radio propagation
   1. Intro to HF radio propagation
   2. What is Radio?
3. A combination of long-term prediction and short-term forecast methods
4. A comparison between Radio and Light propagation phenomena
5. A comprehensive beginner's guide for RF propagation
6. A comprehensive guide to HF propagation
7. A guide for ham radio propagation
8. A guide to HF propagation
9. A guide to HF propagation indicators
10. A guide to understanding ham frequencies
11. A primer on space weather
12. A quick guide to solar indices — A review of skywave propagation indicators
13. A review of significat radio blackout events of the 25th solar cycle
14. A simple guide to get started ham radio propaharion
15. A-index
16. Absorption
17. Absorption of skywaves
18. ACE
19. Active sun
20. Activity Charts and DX Clusters—references
21. Activity map ham radio
22. Activity Map of HF Radio QSOs
23. Advanced techniques in HF propagation forecast
24. Advanced tutorials on HF propagation
25. ALE — Automatic link establishment
26. Alerts
27. All-in-One HF Propagation Resource
28. All bands closed?
29. Amateur ham radio
30. Amateur radio
31. Amateur radio and ionospheric science
32. Amateur radio band conditions
33. Amateur radio bands
34. Amateur radio charactaristics
35. Amateur Radio Current Conditions
36. Amateur radio frequencies
37. Amateur radio frequency allocations
38. Amateur radio frequency list
39. Amateur radio grey-line(British) or Gray-line (American)
40. Amateur radio guide on propagation
41. Amateur radio HF band conditions
42. Amateur radio HF propagation conditions
43. Amateur radio HF propagation frequencies & forecast
44. Amateur radio live maps
45. Amateur radio maps
46. Amateur radio online propagation charts
47. Amateur radio online propagation conditions
48. Amateur radio online propagation maps
49. Amateur radio operator
50. Amateur radio propagation conditions
51. Amateur radio propagation forecast
52. Amateur radio propagation frequencies
53. Amateur Radio Propagation Map
54. Amateur Radio Propagation Now
55. Amateur radio propagation studies
56. Amateur radio propagation today
57. Amateur radio solar activity
58. Amateur radio space weather
59. Amateur Radio Usable HF Propagation Frequencies & Forecast
60. Amateur Radio views and reviews for Beginners
61. Amplitude
62. An intro to ham radio for beginners
63. An introduction for beginners on radio propagation
64. An introduction to HF propagation
65. An introduction to radio wave propagation
66. Analyze HF propagation using DX clusters
67. Antenna directivity
68. Antenna efficiency
69. Antenna for NVIS
70. Antenna gain
71. Antenna height
72. Antenna height, directivity, gain
73. Appleton formula for the refractive index the ionosphere
74. Applications for analyzing and forecasting HF propagation
75. Applications used for forecasts and predictions (references — list of sources)
76. APRS-IS—Automatic Packet Reporting System-Internet Service—references
77. Are there any benefits to solar activity?
78. Aurora | At what Kp index can I see aurora?
79. Aurora forecast
80. Aurora light show
81. Auroral Radar Network (references — list of sources)
82. Australian Space Weather Alert System (2024)
 
B
83. Bad conditions on ham bands
84. Band Activity
85. Band Activity Worldwide
86. Band conditions
87. Band conditions banners
88. Band conditions based on DX charts, PSKR, WSPR, WebSDRs, Beacons
89. Band conditions charts
90. Band Conditions Forecast
91. Band Conditions Ham Radio
92. Band conditions ham radio live
93. Band openings
94. Banners and widgets
95. Banners for band conditions
96. Banners showing propagation conditions
97. Basic amateur radio—HF propagation
98. Basic architecture of radio wave communication
99. Basic electromagnetic wave properties
100. Basic EM wave properties
101. Basic EM wave properties (references — list of sources)
102. Basic intro to ham radio for beginners
103. Basic Wave Propagation, Nor Hadzfizah Binti Mohd Radi (2017)
104. Basics for Short Wave Operation
105. Basic HF propagation for amateur radio
106. Basics of HF propagation
107. Basics of HF radio propagation
108. Basics of Radio Waves
109. Basics of Radio Wave propagation
110. Be prepared for volatile band conditions
111. Be ready to try new frequencies
112. Beacons
113. Beacons—references
114. Beginner's Guide to Ham Radio Range
115. Benefits of the HAARP Project for Radio Hams
116. Best HF frequencies for daytime
117. Best propagation frequency
118. Best solar propagation frequency
119. Beyond line of site (BLOS)
120. Blackouts what are they?
121. Blind zone
122. BLOS (Beyond line of site)
123. Bt - total strength of the Interplanetary Magnetic field (IMF)
124. Bz - orientation of the IMF
 
C
125. Calculate the ionospheric refractive index
126. Calculation of the maximum usable frequency
127. Can a ham radio reach space?
128. Can ham radio communicate with the other side of the globe?
129. Can ham radio talk around the world?
130. Can HF radio propagation be predicted?
131. Can I get shorwave radio on my PC?
132. Carrington event
133. CF vs MUF—Difference between CF and MUF
134. CF vs MUF: Understanding Critical and Maximum Usable Frequencies
135. Challenges in storm forecasting
136. Characteristics of radio waves
137. ChatGPT learns about forecasting tools for radio amateurs
138. Check DX Propagation with Beacons
139. Chirping
140. Choose now the best HF bands for skywave communication
141. Choose the correct amateur band and the right time of the day for long range communications
142. Choosing the right frequency
143. Choosing the right HF frequency
144. Clouds of plasma in the ionosphere
145. CME - coronal Mass ejection
146. Communication blackout
147. Communication blackout 2024
148. Communication blackout meaning
149. Communication blackout today
150. Communication circuit
151. Compare DR2W propagation tool with VOACAP
152. Compare forecasting tools for HF radio propagation
153. Compare forecasting tools for radio amateurs
154. Comparing Ionospheric MUF using IRI16 Model with Mid Latitude (2020)
155. Communication conditions
156. Complex HF propagation Modes | Complex Modes of Skywave Propagation—references
157. Concept of wireless communication
158. Conductive ground
159. Core propagation concepts for radio amateurs
160. Core propagation concepts for skywaves
161. Correlation analysis of Solar activity and Cosmic ray (J_Phys_Conf 2017)
162. Correlation of Sunspot Numbers and Geomagnetic Indices
     with Various Climate Change Parameters (2024)
163. Correlation between conditions, MUF, SSN and SFI
164. Correlation between K and A values
165. Correlation between MUF and solar flux
166. Correlation between SFI and bands openings
167. Correlation Between solar flux and sunspot number
168. Correlation between solar indices band conditions
169. Correlation of sunspot numbers and geomagnetic indices
170. Correlation between sunspot numbers and geomagnetic parameters for solar cycle 24
171. Coronal hole
172. Coronal Mass ejection (CME)
173. Critical frequencies foF2, MUF, OTF, LUF
174. Critical Frequencies LUF vs MUF
175. Critical frequency
176. Critical frequency formula
177. Critical Frequency, LUF, and MUF
178. Critical frequency propagation
179. Critique of IONCAP's Reliability and Service Probability Calculations (1993)
180. Current and predicted fadeouts
181. Current band conditions
182. Current flare
183. Current ham band conditions
184. Current Ham Band Conditions * Charts Explained
185. Current Ham Band Conditions Explained
186. Current ham band propagation
187. Current ham band propagation conditions
188. Current ham conditions
189. Current ham radio condition charts
190. Current ham radio conditions
191. Current ham radio conditions charts
192. Current ham radio propagation
193. Current ham radio propagation charts
194. Current ham radio propagation conditions
195. Current ham radio propagation map
196. Current ham radio propagation report
197. Current HamBands Conditions
198. Current HF Bands Conditions
199. Current HF Band Conditions Maps For Radio Operators
200. Current HF Band conditions online map
201. Current HF Bands Conditions—Charts for Radio Hams
202. Current HF conditions
203. Current HF propagation
204. Current HF Propagation Conditions
205. Current HF Propagation Conditions FAQ
206. Current HF propagation conditions maps for radio operators
207. Current HF propagation map
208. Current HF radio propagation
209. Current Kp index
210. Current LUF conditions
211. Current LUF map
212. Current LUF propagation
213. Current MUF
214. Current MUF Conditions
215. Current optimal frequency charts
216. Current propagation
217. Current propagation chart
218. Current propagation conditions
219. Current radio communication conditions
220. Current radio propagation conditions
221. Current shortwave propagation conditions
222. Current Shortwave propagation conditions map
223. Current skywave propagation
224. Current solar activity
225. Current solar alerts
226. Current solar conditions Ham radio
227. Current solar cycle prediction
228. Current solar events
229. Current Solar Flare
230. Current Solar Terrestrial Activity Report
231. Current space weather
232. Current space weather parameters
233. Current sunspot cycle
234. Current sunspot cycle activity
235. Critical frequency
236. Critical frequency map/chart
 
D
237. D layer of ionosphere is rather a region
238. D region
239. D-Rap model—Global Fadeout Report
240. D-Region Absorption Product
241. D Region Absorption Predictions (D-RAP)
242. Daily sunspots groups
243. Day night live world map
244. Day-night—diurnal cycle
245. Dead Zone
246. Definition of the Ionospheric Regions
247. Defining Electromagnetic Waves
248. Decoding space weather data for HF propagation
249. Detect Changes in Propagation Conditions using RBN, WSPR, PSKR—references
250. Detection and Localization of F-layer Ionospheric Irregularities (2022)
251. Diffraction
252. Digisonde Directogram
253. Digital Reporter
254. Direct wave propagation
255. Disadvantages of NVIS
256. Discover ham radio propagation
257. Discover the current solar and atmospheric conditions
258. Dispertion of light
259. Dispersion of radio waves
260. Distance between NVIS stations?
261. Disturbance-storm time (Dst) index
262. Diurnal cycle
263. DRAP
264. DR2W - DX propagation
265. Dst
266. Ducting
267. DX band condition
268. DX charts
269. DX conditions
270. DX conditions now
271. DX conditions today
272. DX clusters
273. DX ham band conditions
274. DX map | DX propagation map
275. DX Propagation Forecasting
276. DX propagation online map
277. DX propagation prediction
278. DX radio live
279. DX Spots
280. DXFun
281. DXMAPS
282. DXView HF map
283. DXWatch
 
E
284. E layer of ionosphere is rather a region
285. E-region
286. E-sporadic forecast - propquest
287. Earth's Atmosphere Layers
288. Earth's Ionosphere Regions
289. Earth's magnetic field
290. Earth's Magnetosphere
291. Earth Magnetosphere vs Earth's magnetic field
292. Earth observing system (EOS)
293. Earth's magnetic field
294. Easy learning radio propagation
295. Effects of geomagnetic storms on ham radio
296. Effects of geomagnetic storms on radio hams
297. Effects of ionospheric motions and irregularities on HF radio propagation
298. Effects of radio waves
299. Effects of solar activity on amateur radio
300. Electromagnetic Radiation
301. Electromagnetic Radiation—Radio waves properties ► Radio propagation—references
302. Electromagnetic Spectrum ↗
303. Electromagnetic Wave
304. Electromagnetic Waves Basics
305. Electromagnetic Wave Propagation
306. Electron densities
307. Electron flux (Ef)
308. Elevation Angle
309. EM wave Properties
310. EME Deg - earth-Moon-Earth Degradation
311. Equatorial Spread-F Ionospheric dynamics (1962)
312. EsEU - Sporadic E Europe
313. EsNA - Sporadic E North America
314. Estimated sunspot number
315. Etymology of ham radio
316. EUV sunlight
317. Evaluation of models for HF propagation prediction
318. Evolution of forecasting techniques
319. Explain DRAP for radio amateurs
320. Explain ham bands
321. Explain HF propagation charts
322. Explain HF propagation conditions maps and charts
323. Explain HF propagation indicators
324. Explain HF propagation indices
325. Explain how solar data is reelated to HF propagation
326. Explain propagation banners
327. Explain skywave erratic propagation conditions
328. Explain skywave propagation (key factors)
329. Explain skywave propagation charts
330. Explain space weather for radio amateurs
331. Explain space weather indices
332. Explain solar indices
333. Explain what does it mean ham bands closed
334. Explore ham radio communications
335. Explore HF propagation
336. Explore the world of amateur radio
 
F
337. F layer of ionosphere is rather a region
338. Fadeouts
339. Fading
340. Fading due to irregularities of ionospheric regions
341. FAQ on HF propagation
342. F10.7—Solar radio flux measures solar radio emission at 10.7 cm (2,800 MHz)
343. F-region
344. Find charts showing the live conditions
345. Find your opening on the map
346. Finding the best operating frequencies for skywave propagation
347. Flares
348. f_oF₂ (F2 critical frequency)
349. foF2 map
350. fof2 real time
351. fof2 today
352. Forecast ham band conditions
353. Forecast HF bands conditions
354. Forecast HF radio propagation - applications
355. Forecast HF propagation conditions
356. Forecast of HF propagation for radio amateurs
357. Forecast of The Ham radio propagation
358. Forecast propagation
359. Forecast propagation for radio amateurs
360. Forecast proton flux
361. Forecast radio skywave conditions
362. Forecast radio skywave propagation
363. Forecast short wave propagation conditions
364. Forecast skywave conditions
365. Forecast skywave propagation
366. Forecast solar flare
367. Forecast vs Prediction
368. Forecast vs prediction of HF band conditions
369. Forecasting and Prediction
370. Forecasting evolution over the last 30 years
371. Forecasting HF propagation for radio amateurs
372. Forecasting ionospheric disturbances
373. Forecasting MUF for a 3000 km path
374. Forecasting tools for radio amateurs
375. Forecasting vs. Prediction
376. Free Electron Density
377. Free gray line map
378. Free HF propagation mapping software
379. Free RF propagation mapping software
380. Free Online HF Propagation Tool for Technical and Non-Technical Users
381. Free RF propagation mapping software
382. Free Resource for Amateur Radio Beginners
383. Frequency allocation
384. Frequency of optimum transmission (FOT)
385. Frequency of optimum traffic (FOT)
386. Fundamentals of electromagnetic wave propagation explained
387. Fundamentals of radio propagation
388. Fundamentals of radio waves propagation
 
G
389. G₀-G₅: scale of geomagnetic activity
390. Gamma rays
391. Gama rays bursts (GRB) a cosmic event
392. Generation of Radio Waves
393. "GeoMag" (index) - earth`s geomagnetic activity
394. Geomagnetic activity
395. Geomagnetic activity forecast
396. Geomagnetic conditions
397. Geomagnetic data
398. Geomagnetic disturbance | Geomagnetic disturbances | Geomagnetic effects
399. Geomagnetic field
400. Geomagnetic field activity
401. Geomagnetic forecast
402. Geomagnetic indices
403. Geomagnetic indices explained Quick guide
404. Geomagnetic indices K, A, HPo
405. Geomagnetic storms
406. Geomagnetic storm and equatorial spread-F (2004)
407. Geomagnetic Storm Dynamics
408. Geomagnetic storm ham radio
409. Geomagnetic Storm Impacts
410. Geomagnetic storms ham radio
411. Geomagnetic storm radio amateur
412. Geomagnetic storms
413. Geophysical activity
414. Getting Started in HF
415. Global conditions | Global conditions banners
416. Global HF conditions
417. Global HF fadeout
418. Global HF propagation
419. Global radio propagation conditions
420. Global vs Regional HF propagation conditions
421. GMF
422. Gray-line or grey-line
423. Gray line live map
424. Gray line propagation
425. GRB - Gama-rays bursts
426. Grey Line Map
427. Grey line map real time
428. Greyline short explanation
429. Greyline propagation
430. Greyline radio propagation explained
431. Greyline vs "Solar Terminator"
432. Ground wave and sky propagation
433. Ground wave propagation ↗
434. Ground wave vs skywave
435. Ground waves
436. Guide for radio hams on HF propagation
437. Guide to radio wave propagation, studies, guides and documentation
 
H
438. Hale cycle
439. Ham activity
440. Ham band activity
441. Ham band condition charts
442. Ham band condition now
443. Ham band conditions
444. Ham band list
445. Ham band propagation chart
446. Ham band propagation characteristics
447. Ham band propagation conditions
448. Ham band propagation map
449. Ham band report
450. Ham band status
451. Ham bands closed
452. Ham bands conditions
453. Ham bands map | Ham band map
454. Ham bands open
455. Ham bands' activity
456. Ham condition chart
457. Ham conditions
458. Ham DX map
459. Ham propagation
460. Ham propagation dashboard
461. Ham propagation map
462. Ham Radio - Shortwave Band List
463. Ham radio atmospheric conditions
464. Ham radio band characteristics
465. Ham radio band conditions
466. Ham radio band frequencies
467. Ham radio band conditions app
468. Ham radio band conditions map
469. Ham radio band conditions today
470. Ham radio band frequencies
471. Ham radio band plan
472. Ham radio band plan (list of references)
473. Ham radio band propagation
474. Ham radio band propagation characteristics
475. Ham radio band propagation chart
476. Ham radio bands
477. Ham radio bands and frequencies | Ham radio bands & frequencies
478. Ham Radio Bands: Frequencies and Characteristics
479. Ham radio basics: Beginners guide to HF radio propagation
480. Ham radio charts
481. Ham radio communications
482. Ham radio condition
483. Ham radio condition charts
484. Ham radio condition map
485. Ham radio condition maps
486. Ham radio conditions
487. Ham radio conditions map
488. Ham radio conditions today
489. Ham radio current conditions
490. Ham radio dead bands
491. Ham radio DX live streaming
492. Ham radio DX map
493. Ham radio for Beginners
494. Ham radio for Newbees
495. Ham radio for Newbeis
496. Ham radio frequencies
497. Ham radio frequencies and bands | Ham radio frequencies & bands
498. Ham radio frequencies chart
499. Ham radio frequencies conditions
500. Ham radio frequencies explained
501. Ham radio frequencies list
502. Ham radio frequencies propagation charts
503. Ham radio frequencies to listen to
504. Ham radio frequencies & bands in the USA
505. Ham radio frequency allocation
506. Ham radio frequency chart
507. Ham radio frequency guide
508. Ham radio frequency range chart
509. Ham Radio Glossary of Terms
510. Ham Radio Guide for HF propagation
511. Ham radio HF band conditions
512. Ham radio HF conditions
513. Ham radio HF propagation real-time
514. Ham radio high frequency band
515. Ham radio live
516. Ham radio MUF
517. Ham radio operating frequency chart
518. Ham radio propagation
519. Ham radio propagation app
520. Ham radio propagation charts
521. Ham radio propagation conditions
522. Ham radio propagation current conditions
523. Ham radio propagation forecast
524. Ham radio propagation forecasts
525. Ham radio propagation frequencies
526. Ham radio propagation indices
527. Ham radio propagation introduction
528. Ham radio propagation live map
529. Ham radio propagation map
530. Ham radio propagation overview
531. Ham radio propagation now
532. Ham radio propagation prediction
533. Ham radio propagation real-time
534. Ham radio propagation review
535. Ham radio propagation today
536. Ham radio propagation tutorial
537. Ham radio propagation websites
538. Ham Radio Propagation YouTube
539. Ham radio propagation: Solar conditions
540. Ham radio QSO planner
541. Ham Radio Range Guide
542. Ham Radio Range Guide: How Far Can You Talk?
543. Ham Radio Range: How Far Can You Talk With It?
544. Ham radio secrets
545. Ham radio skywave tutorial
546. Ham radio solar activity
547. Ham radio solar conditions
548. Ham radio solar cycle
549. Ham radio solar weather
550. Ham radio space weather
551. Ham radio websites
552. Ham radio websites about forcasing HF propagation
553. Ham radio sun conditions
554. Ham radio sunspot
555. Ham radio sunspot conditions
556. Ham radio sunspots now
557. Ham radio Today
558. Ham radio wave propagation
559. Ham Radio YouTube Channels Skywave Propagation
560. Ham Solar
561. Ham solar conditions
562. HamSCI Space Weather Operational Resources and
     Needs of the Amateur Radio Community (2020)
563. Heliophysics
564. Heliophysics and Amateur Radio
565. Heliosphere
566. Heliospheric Current Sheet (HCS)
567. Helioviewer
568. Helium lines
569. HF—High frequency
570. HF band conditions
571. HF band conditions maps
572. HF band conditions regional
573. HF Band conditions: A Comprehensive Guide
574. HF band openings
575. HF band propagation FAQ
576. HF bands - what to expect
577. HF bands affected by solar conditions
578. HF bands allocated for radio amateurs
579. HF bands allocated for radio amateurs and their characteristics
580. HF bands allocated for radio amateurs and their features
581. HF bands ham radio guide
582. HF bands assigned to hams
583. HF bands assigned to radio amateurs
584. HF Bands Ham Radio Guide
585. HF bands open now
586. HF band propagation chart
587. HF bands monitoring
588. HF communication
589. HF communication prediction tools
590. HF communications response to solar activity
591. HF conditions
592. HF conditions at a glance
593. HF Conditions in Real Time
594. HF conditions UK
595. HF critical frequency
596. HF DXView
597. HF frequency range
598. HF guide for all level radio ham
599. HF ham radio bands
600. HF ham radio bands: HF frequencies
601. HF ham radio DX
602. HF ham radio for beginners
603. HF open now
604. HF openings now
605. HF prediction
606. HF Propagation
607. HF Propagation alerts
608. HF Propagation and the Ionosphere
609. HF propagation and solar-terrestrial data
610. HF propagation app
611. HF propagation applications
612. HF propagation bad conditions
613. HF propagation basics
614. HF propagation blackout
615. HF propagation calculator
616. HF propagation chart
617. HF propagation charts
618. HF Propagation Condition Map
619. HF propagation conditions
620. HF propagation conditions explained
621. HF propagation conditions: forecasting and prediction
622. HF propagation conditions at a glance
623. HF propagation data
624. HF propagation data app
625. HF propagation data seasons
626. HF propagation data study
627. HF propagation disruptions AU
628. HF propagation disruptions UK
629. HF propagation disruptions US
630. HF propagation Europe
631. HF propagation experts
632. HF propagation explained
633. HF propagation explanation
634. HF propagation fadeouts
635. HF propagation fluctuations
636. HF propagation for advanced hams
637. HF Propagation for amateurs
638. HF propagation for beginners
639. HF propagation for beginners and advanced
640. HF propagation for ham operators
641. HF Propagation for ham radio explained
642. HF propagation for hams explained
643. HF propagation for newbees
644. HF Propagation for amateurs
645. HF Propagational Resources
646. HF propagation for radio amateurs
647. HF propagation for radio hams
648. HF propagation forecast
649. HF propagation forecast applications
650. HF propagation forecast for radio amateurs
651. HF propagation forecast tool KC2G
652. HF propagation forecast tools (references)
653. HF propagation forecasting
654. HF propagation forcasts
655. HF propagation fundamentals
656. HF propagation guide
657. HF propagation guide for radio hams
658. HF propagation indicators
659. HF propagation ionospheric disturbances
660. HF propagation live chart
661. HF propagation live map
662. HF propagation map
663. HF propagation mapping software
664. HF propagation models
665. HF propagation modes
666. HF propagation modes overview
667. HF propagation mysteries
668. HF propagation now (real-time)
669. HF propagation odd conditions
670. HF propagation online map
671. HF propagation online reports
672. HF propagation overview
673. HF propagation planner
674. HF propagation planning
675. HF propagation planning tool
676. HF propagation prediction
677. HF propagation prediction online
678. HF propagation prediction software
679. HF propagation prediction tools
680. HF propagation predictions
681. HF propagation preface
682. HF propagation reporter
683. HF propagation reports
684. HF propagation scale
685. HF propagation seasonal anomaly
686. HF propagation shortcast overview
687. HF propagation shortcast review
688. HF propagation score
689. HF propagation shortcasts a folder of brief podcasts less than 15 minutes
690. HF Propagation software review
691. HF Propagation solar indicators
692. HF propagation status
693. HF Propagation status and alerts
694. HF propagation tools
695. HF propagation tutorials
696. HF propagation tutorial for radio amateurs
697. HF propagation tutorials
698. HF propagation today
699. HF propagation tools
700. HF propagation using solar index
701. HF propagation what is it?
702. HF propagation widget
703. HF Propagation YouTube
704. HF radio bands and propagation
705. HF radio glossary
706. HF radio communication
707. HF radio communication circuit
708. HF radio conditions
709. HF radio propagation
710. HF radio propagation app
711. HF radio propagation bands
712. HF radio propagation basics
713. HF radio propagation chart ↗ ↗
714. HF radio propagation conditions
715. HF radio propagation during a solar storm
716. HF radio propagation for beginners
717. HF radio propagation forecast
718. HF radio propagation indices and scales
719. HF propagation map Nowcast
720. HF radio propagation map: Explanation of real-time MUF 3,000 km propagation map
721. HF radio propagation maps
722. HF radio propagation modes
723. HF radio propagation now
724. HF radio propagation prediction | HF radio propagation prediction compared to forecast
725. HF radio propagation seasons
726. HF radio propagation tutorials for radio amateurs
727. HF radio propagation software
728. HF radio propagation today
729. HF skywave communication circuit
730. HF radio wave propagation
731. HF radio wave propagation factors
732. HF radio waves (basics)
733. HF real-time propagation
734. HF regional conditions
735. HF signals propagation
736. HF skywave communication
737. HF skywave window: LUF—MUF
738. HF space weather
739. HF Systems MUF maps and forecasting charts
740. HF wave propagation
741. HFTA - High frequency Terrain Assessment
742. High frequency communication circuit
743. High frequency communications response to solar activity
744. High frequency (HF) amateur radio
745. High frequency propagation software
746. High frequency radio propagation
747. Highest frequency bands at night
748. Highest Possible Frequency (HPF)
749. History of amateur radio
750. How are current band conditions?
751. How are HF conditions determined?
752. How are ionospheric conditions measured?
753. How can I monitor HF bands without having a good receiver and antenna?
754. How can I operate during solar storms?
755. How can I use my PC as a ham band monitor?
756. How can propagation reports help ham radio operators
757. How can we forecast changes in HF conditions over the next hour?
758. How can we forecast HF propagation conditions?
759. How do disturbances such as solar flares, geomagnetic storms, and traveling ionospheric disturbances affect radio wave propagation?
760. How do geomagnetic storms affect radio wave propagation?
761. How do I find open ham bands
762. How do I find out what bands are open?
763. How do radio frequencies work?
764. How do ionospheric disturbances affect radio wave propagation?
765. How do radio waves bounce off the ionosphere for long-distance communication?
766. How do radio waves propagate?
767. How do radio frequencies work?
768. How do radio waves carry data?
769. How do radio waves travel through the Earth's atmosphere?
770. How do radios work?
771. How do solar flares affect radio wave propagation?
772. How do solar flares cause geomagnetic storms?
773. How do solar storms affect radio propagation?
774. How do solar storms cause geomagnetic storms?
775. How do the seasons affect HF radio propagation?
776. How do traveling ionospheric disturbances affect radio wave propagation?
777. How do you interpret HF propagation map?
778. How do you read HF band conditions?
779. How do we communicate using radio waves?
780. How do we monitor space weather?
781. How does a fadeout happen?
782. How does geomagnetic activity affect HF propagation?
783. How does elevation affect HF propagation?
784. How does HF propagation work?
785. How does HF radio propagate?
786. How does ionospheric propagation take place?
787. How does ionospheric propagation work?
788. How does radio waves compare to visible light?
789. How does space weather affect ham radio?
790. How does the ionosphere affect HF radio propagation?
791. How does the ionosphere affect radio wave propagation?
792. How does the ionosphere couple with the neutral atmosphere and with space?
793. How does the ionosphere respond to inputs from space and from the neutral atmosphere?
794. How does the sun affect radio communication?
795. How far can a ham radio reach?
796. How far can ham radio talk?
797. How far can HF radio go?
798. How far can HF radio transmit?
799. How far can HF transmit?
800. How far can I communicate by radio?
801. How far can I talk with my ham radio?
802. How far can you talk on ham radio?
803. How far will a radio transmit?
804. How ionospheric structure affects radio refraction
805. How radio waves carry data?
806. How Radio Waves Propagate
807. How skywave propagation works?
808. How solar storms affect ham radio propagation
809. How the Sun powers the ionosphere
810. How to assess propagation?
811. How to choose antenna?
812. How to choose ham band based on propagation conditions?
813. How to determine HF propagation conditions?
814. How to determine if a band is open?
815. How to find out propagation conditions now
816. How to improve HF communication frequency selection ability?
817. How to know if a band is open?
818. How to plan your QSO with VOACAP?
819. How to predict MUF?
820. How to read HF band conditions?
821. How to Read Propagation Charts for HF DXing
822. How to Read Propagation Indices for HF DXing
823. How to select a frequency for NVIS operation?
824. How to use a remote HF radio receiver?
825. How to use NVIS?
826. How to use propagation forecast charts?
827. How to use propagation tools effectively
828. How will a solar storm affect my ham radio activities?
829. HPF—Highest Possible Frequency
830. Hybrid ionospheric models
 
I
831. IMF - Interplanetary Magnetic field
832. Impacts of space weather
833. Impacts of space weather on HF radio communications
834. Impact of the sun
835. Index of refraction—Glass's refractive index in comparison to plasma/ionosphere
836. Incident angle
837. Information about amateur radio frequencies
838. Interplanetary magnetic field (IMF)
839. Interpretation of the propagation indices
840. Introduction to HF propagation
     Recommended references:
     1. Introduction to HF Radio Propagation Australian Gov (2002)
     2. Introduction to-HF Radio Propagation Australian Gov (2007)
     3. Ionospheric Propagation, Prof. Sean Victor Hum (2018)
841. Ionospheric propagation
842. Ionospheric propagation frequency range
843. Ionospheric Radio Propagation, Kenneth Davies (1965)
844. Ionospheric regional conditions
845. Introduction to Ionospheric Propagation
846. Introduction to Radio Communications Principles
847. Introduction to RF propagation
848. Ionisation
849. Ionization
850. IonoProbe
851. Ionogram
852. Ionograms (references — list of sources)
853. Ionosonde
854. Ionosondes (references — list of sources)
855. Ionosondes HF propagation
856. ionosphere
857. Ionosphere — HF radio propagation;
     Multi-refractions; free electron density and Geomagnetic storms
858. Ionosphere and HF
859. Ionosphere and radio signals
860. Ionosphere and skywave propagation;
     Ionization of D, E and F regions | Free-electron density | Skywaves
861. Ionosphere at night
862. Ionosphere conditions
863. Ionosphere dynamics
864. Ionosphere is a part of which layer of atmosphere?
865. Ionosphere is also known as...
866. Ionosphere layers diagram
867. Ionosphere probing
868. Ionosphere propagation
869. Ionosphere regions
870. Ionosphere temperature
871. Ionosphere understanding
872. Ionosphere, radio waves
873. Ionosphere, space weather and radio propagation
874. Ionosphere’s influence
875. Ionospheric absorption
876. Ionospheric anomalies (references — list of sources)
877. Ionospheric bubbles
878. Ionospheric clouds
879. Ionospheric conditions explained
880. Ionospheric conditions overview
881. Ionospheric data
882. Ionospheric dispertion of radio waves
883. Ionospheric distortion
884. Ionospheric disturbances
885. Ionospheric disturbances and HF propagation conditiona
886. Ionospheric disturbances and their impacts on HF radio wave propagation
887. Ionospheric disturbances probing (references — list of sources)
888. Ionospheric dynamics
889. Ionospheric effects on hf radio wave propagation
890. Ionospheric interference
891. Ionospheric irregularities
892. Basic Ionospheric models (references — list of sources)
• Ionospheric models
• Ionospheric models that simulate a neural network
• Ray-tracing models
• Skywave propagation indicators
• Hybrid ionospheric models
893. Ionospheric monitoring and HF frequency management
894. Ionospheric prediction and HF frequency management
895. Ionosphere propagation
896. Ionospheric propagation chart
897. Ionospheric propagation map
898. Ionospheric propagation examples
899. Ionospheric propagation model
900. Ionospheric propagation of radio waves explained
901. Ionospheric propagation theory
902. Ionospheric radio propagation
903. Ionospheric reflection (resources)
904. Ionospheric regions
905. Ionospheric regions (references — list of sources)
906. Ionospheric regions and HF Skywaves
907. Ionospheric research (references — list of sources)
908. Ionospheric skywave propagation
909. Ionospheric storms
910. Ionospheric variations (references — list of sources)
911. Is HF propagation reciprocal?
912. IRI ionospheric model
913. ITU model
 
J
914. John Ashworth Aatcliffe (12-December-1902-25-October 1987)
 
K
915. KC2G HF MUF propagation maps
916. Keep an Eye on the High Bands
917. Key aspects of radio propagation for hams
918. Key concepts of electromagnetic wave propagation
919. Key concepts of HF propagation
920. Key factors affecting HF propagation
921. Key for HF Propagation Charts
922. Key Propagation Modes
923. K-Index
924. K-index Australia
925. K-index United Kingdom
926. K-index United States
927. Kp index
928. Kp index Aurora
929. Kp Index Explained
930. Kp index Nowcast
931. KiwiSDR map of remote public SDR receivers accessible via the Internet
 
L
932. Lagrange points
933. Latest DX Propagation
934. Latest HF Bands Propagation, DX
935. Layers or regions of the ionosphere?
936. Learn basic radio propagation
937. Learn High-Frequency Propagation
938. Learn how to interpret propagation charts for improved HF band communication
939. Learn skywave propagation
940. Learning about space weather
941. Line of sight propagation (LOS)
942. Live DX spot reports by ham radio
943. Live ham band reports
944. Live ham radio band conditions
945. Live ham radio map
946. Live ham radio propagation
947. Live ham radio reports
948. Live HF DX propagation maps
949. Live HF propagation
950. Live HF propagation charts and maps
951. Live HF propagation map
952. Live HF propagation maps and charts
953. Live HF propagation maps and charts explained
954. Live Propagation and Solar Data
955. Live radio propagation map
956. Live radio propagation reports
957. Live solar activity
958. Live solar alerts for ham radio
959. Live solar events and past solar activity
960. List of ham radio frequencies
961. Listen live ham radio
962. LOS—Line of sight propagation
963. Long and mid-range skywaves
964. Long distance communication
965. Long-and short-term prediction of HF radio propagation
966. Long-term HF propagation planning
967. Long-term prediction and short-term prediction of HF radio propagation
968. Lowest & Maximum Usable Frequency, Critical Frequency
969. Lowest usable frequecy (LUF)
970. Lowest Usable Frequency map
971. LUF frequency range due to SID
972. LUF frequency range chart
973. LUF (Lowest Usable frequency)
974. LUF chart
975. LUF chart for radio amateurs
976. LUF map
977. LUF Propagation Map
978. LUF-MUF window:
 
M
979. Magic band openings
980. Magnetic field
981. Magnetosphere (MS)
982. Making sense of solar indices
983. Mastering HF propagation
984. Maximum usable frequency (MUF)
985. Maximum Usable frequency map
986. Methods for evaluating the current band conditions
987. Methods for forecasting band conditions
988. Methods for monitoring HF propagation
989. Methodes to forecast radio propagation
990. Minimum usable frequecy—The lowest usable frequency (LUF)
991. Model evaluation
992. Model validation
993. Model verification
994. Modeling the Topside Ionosphere Observations by Satellites (2003)
995. Models
996. Modes of HF radio propagation
997. Modes of radio propagation
998. Modes of Radio Wave Propagation in Wireless Communication
999. Monitor band activity of radio amateurs ↗
1000. Monitor Worldwide HF HAM Band Activity
1001. Monitoring and forecasting skywave propagation
1002. Monitoring HF band activity
1003. Monitoring HF band conditions
1004. Moniotring HF propagation
1005. Monitoring solar flux levels for promising band openings
1006. MS — Meteor Scatter Activity
1007. MUF | Maximum Usable Frequency
1008. MUF(3000)F2 plots
1009. MUF 3000 km map
1010. MUF and LUF
1011. MUF calculation
1012. MUF calculator
1013. MUF factor
1014. MUF ham radio
1015. MUF Indicator
1016. MUF indicators
1017. MUF LUF FOT
1018. MUF LUF prediction
1019. MUF map
1020. MUF map real time
1021. MUF maps and charts
1022. MUF meaning
1023. MUF propagation
1024. MUF propagation chart
1025. MUF propagation map
1026. MUF propagation map: Assess optimal frequencies and paths
1027. MUF propagation online map
1028. MUF radio propagation
1029. MUF radio propagation map
1030. MUF, LUF, and FOT
1031. My current local HF conditions
1032. Mystery in wave propagation conditions
 
N
1033. Near real-time HF propagation charts
1034. Near real-time F2-region critical frequency map
1035. Near real-time regional maps
1036. Near real-time skywave propagation charts
1037. Near Vertical Incidence Skywave
1038. NET ionospheric model
1039. NM7M HF Propagation tutorial by Bob Brown, NM7M
1040. NOAA
1041. NOAA predicted sunspot number
1042. NOAA Radio dashboard
1043. NOAA solar cycle
1044. NOAA solar flux predictions
1045. NOAA sunspot cycle predictions
1046. NOAA SWPC space weather scales
1047. Noise level
1048. Notable solar storms during the 25th solar cycle
1049. Nowcast HF propagation conditions
1050. Number of radio amateurs by country
1051. NVIS
1052. NVIS antenna
1053. NVIS antennas explained
1054. NVIS Antennas Theory & Practice
1055. NVIS HF signal propagation in ionosphere
1056. NVIS map
1057. NVIS propagation
1058. NVIS propagation concept
1059. NVIS propagation maps—Amateur and commercial operators
1060. NVIS propagation problems
1061. NVIS tutorial
1062. NVIS vs conventional skywave
1063. NVIS: Stephen C. Finch AI0W (2008)
 
O
1064. Observations - Geo (Terrestrial) & Solar
1065. Observations and Modeling of Traveling Ionospheric Disturbances
1066. Odd propagation conditions
1067. Official ham band plans, tables and charts
1068. On-Line HF Propagation Forecast
1069. On-line HF Propagation Prediction
1070. Online chart of the recent LUF
1071. Online HF propagation prediction
1072. Online indices
1073. Online LUF chart
1074. Online LUF map
1075. Online propagation charts
1076. Online propagation tools
1077. Online HF propagation prediction
1078. Online propagation tools
1079. Online radio planning
1080. Online radio planning software
1081. Online real-time propagation charts
1082. Open ham bands
1083. Optical dispertion of light vs Ionospheric dispertion of radio waves
1084. Optimal sending frequency
1085. Optimizing HF Bands: Frequency, Propagation, and Time-of-Day
1086. Optimum traffic frequency (OTF)
1087. Optimum transmission frequency (OTF)
1088. Optimizing HF Bands—Frequency, Propagation, and Time-of-Day
1089. Overview Of Electromagnetic Wave Propagation
1090. OWF — Optimum Working frequency
 
P
1091. Past solar activity
1092. PCA (polar cap absorption)
1093. Phase
1094. Physics of Propagation - Refraction Absorption Polarization
1095. Plan ahead an HF QSO
1096. Plan HF QSO for the next day
1097. Plan HF QSO for the next week
1098. Plan HF QSO for the next month
1099. Plan HF communication on ham bands
Plan QSO for the next month Plan QSO for the next week
1100. Plan your QSO today
1101. Plan your QSO with VOACAP
1102. Plan Your QSOs
1103. Plan your HF radio operations now, the next 24 hours and more
1104. Planning a QSO with VOACAP
1105. Plasma
1106. Plasma clouds
1107. Point-to-Point 24-hour HF propagation forecast
1108. Point-to-Point 24-hour HF propagation planner
1109. Polar cap absorption event (PCA)
1110. Polarization
1111. Popular Propagation Tools for Amateur Radio
1112. Position in the Electromagnetic Spectrum
1113. PSKR, WSPR
1114. Practical applications
1115. Practical approach
1116. Practical Forecasting and Prediction
1117. Practical guide
1118. Predict conditions
1119. Predict HF propagation radio propagation
1120. Predict MUF
1121. Predict propagation
1122. Predict skywave propagation—nowcast
1123. Predict solar flux
1124. Predict space weather
1125. Predict sunspot numbers
1126. Prediction of sky-wave propagation conditions
1127. Predicting HF Band Conditions for Ham Radio
1128. Predicting HF propagation
1129. Predicting ionospheric conditions
1130. Predicting propagation
1131. Predicting propagation of skywave
1132. Predicting radio propagation
1133. Predicting skywave propagation
1134. Predicting solar flares
1135. Predicting solar flux
1136. Prediction
1137. Prediction vs forecast of HF band conditions
1138. Principles of radio wave propagation
1139. Probing ionospheric disturbances (references — list of sources)
1140. Propagation
1141. Propogation and RadioScience, KL7AL (ARRL 2005)
1142. Propagation and Sun
1143. Propagation beginner's guide
1144. Propagation characteristics of radio waves
1145. Propagation characteristics analysis of high-frequency radio waves
1146. Propagation charts tutorial
1147. Propagation conditions
1148. Propagation conditions for DX
1149. Propagation forecast
1150. Propagation HF prediction
1151. Propagation indicators
1152. Propagation indicators: foF2, MUF, OWF, LUF
1153. Propagation indices
1154. Propagation — modes of HF radio propagation
1155. Propagation charts for ham radio↗ ↗
1156. Propagation condition map
1157. Propagation conditions
1158. Propagation DX
1159. Propagation explained
1160. Propagation factors & conditions
1161. Propagation forecast
1162. Propagation forecast for HF radio
1163. Propagation forecast methodes
1164. Propagation forecast software ham radio
1165. Propagation forecasts for radio amateurs
1166. Propagation guide for radio hams
1167. Propagation indices (plural of propagation index)
1168. Propagation live map
1169. Propagation map
1170. Propagation map for ham radio
1171. Propagation maps for ham radio
1172. Propagation modes
1173. Propagation Modes—Presentation, Ken Larson, KJ6RZ (2024)
1174. Propagation of electromagnetic waves
1175. Propagation of HF radio waves
1176. Propagation of radiowaves
1177. Propagation of radio waves
1178. Propagation of radio waves explained
1179. Propagation of radio waves: ground wave vs. skywave
1180. Propagation of RF Signals
1181. Propagation of high frequency radio waves — The rebirth of HF
1182. Propagation of radio waves for beginners
1183. Propagation of shortwave radio
1184. Propagation of short radio waves
1185. Propagation online map
1186. Propagation Overview 48-Hour
1187. Propagation prediction
1188. Propagation predictions for HF operation
1189. Propagation prediction programs and forecasts
1190. Propagation prediction software for skywave propagation
1191. Propagation prediction software ham radio
1192. Propagation Prediction Tool
1193. Propagation prediction tools
1194. Propagation Prediction Tools
1195. Propagation radio stations map
1196. Propagation report ham radio
1197. Propagation reports
1198. Propagation reports for digital modes
1199. Propagation software
1200. Forecasting communication conditions over the next 24 hours
1201. Forecasting tools
1202. Propagation tools for ham radio
1203. Propagation tools to help succeed with your ham radio
1204. Propagation Tutorial | Table of contents
1205. Propagation visualization
1206. Properties of electromagnetic waves
1207. Properties of radio waves
1208. Proton flux (Pf)
1209. PSKR - PSK reporter
 
Q
1210. QSL net propagation
1211. QSO Activity reports
1212. Quick guide to HF propagation using solar indices
1213. Quiet sun
 
R
1214. R-S-G Scales defined
1215. R-S-G Scales now
1216. R1-R5: Scale of Radio blackouts
1217. Radio amateur HF tutorial
1218. Radio blackout phenomenon
1219. Radio Amateur
1220. Radio blackout
1221. Radio blackout effects
1222. Radio blackout map
1223. Radio blackout phenomenon
1224. Radio blackout today
1225. Radio blackouts
1226. Radio amateurs HF bands charactaristics
1227. Radio blackouts due to solar storms
1228. Radio blackout events during 2024
1229. Radio communication and the ionosphere
1230. Radio Communication Circuit
1231. Radio communications dashboard
1232. Radio coverage simulation software long-term
1233. Radio coverage simulation software short and long terms
1234. Radio fadeouts
1235. Radio frequency
1236. Radio frequency allocations
1237. Radio Frequency (RF) Fundamentals
1238. Radio frequency chart
1239. Radio frequency communication circuit
1240. Radio frequency telecommunication circuit
1241. Radio frequency range chart
1242. Radio frequency ranges chart
1243. Radio frequency table
1244. Radio frequency use chart
1245. Radio frequency and Ionosphere
1246. Radio frequency propagation
1247. Radio frequency propagation
1248. Radio frequency propagation: A comprehensive beginner’s guide
1249. Radio frequency propagation for ham radio
1250. Radio frequency propagation: A Comprehensive Guide
1251. Radio ham bands live
1252. Radio ham HF band conditions
1253. Radio propagation | Radio Propagation—references
1254. Radio propagation - what is it?
1255. Radio propagation and space weather
1256. Radio propagation basics
1257. Radio propagation beacon
1258. Radio propagation charts
1259. Radio propagation conditions map
1260. Radio propagation conditions today
1261. Radio propagation data map
1262. Radio propagation explained
1263. Radio propagation for beginners
1264. Radio propagation for hams explained
1265. Radio Propagation Forecast
1266. Radio propagation forecasting
1267. Radio propagation formula
1268. Radio propagation free planning tools
1269. Radio propagation free software
1270. Radio propagation frequency
1271. Radio propagation indicators
1272. Radio propagation indices
1273. Radio propagation levels map
1274. Radio propagation live map
1275. Radio propagation map
1276. Radio propagation mapping software current status
1277. Radio propagation mapping software forecast
1278. Radio propagation maps
1279. Radio propagation methods
1280. Radio propagation metrics
1281. Radio propagation model
1282. Radio propagation modeling
1283. Radio propagation planning
1284. Radio propagation planning tools (forecast)
1285. Radio propagation planning tools (preduction)
1286. Radio Propagation Prediction
1287. Radio propagation prediction for HF communications
1288. Radio propagation prediction vs. foracasting
1289. Radio propagation prediction modelling
1290. Radio Propagation Online Tools
1291. Radio Propagation Overview
1292. Radio Propagation Overview Recent 48-Hours
1293. Radio propagation properties
1294. Radio propagation report
1295. Radio propagation seasonal anomaly
1296. Radio propagation simulator (forecast)
1297. Radio propagation simulator (preduction)
1298. Radio propagation software
1299. Radio propagation today
1300. Radio propagation tool
1301. Radio propagation tutorials
1302. Radio propagation YouTube
1303. Radio spectrum | Radio Spectrum—references
1304. Radio spectrum allocation
1305. Radio spectrum management and allocations
1306. Radio wave
1307. Radio wave fundamentals
1308. Radio wave interaction with the environment
1309. Radio wave principles
1310. Radio wave propagation
1311. Radio wave propagation
1312. Radio wave propagation fundamentals
1313. Radio wave propagation guide
1314. Radio wave propagation in the ionosphere
1315. Radio wave propagation model
1316. Radio Wave Propagation part-1 Introduction, Marcel H. De-Canck, ON5AU (2002)
1317. Radio wave propagation tutorial
1318. Radio wave HF propagation models
1319. Radio wave characteristics
1320. Radio wave propagation charactaristic
1321. Radio wave propagation forecasting
1322. Radio wave propagation in the ionosphere
1323. Radio wave propagation today
1324. Radio wave transmission
1325. Radio waves
1326. Radio waves and communcations distance
1327. Radio waves and the ionosphere—effetcs
1328. Radio waves and the ionosphere-regions
1329. Radio Waves and the Ionosphere, G3YWX (QST 1999)
1330. Radio waves examples
1331. Radio waves nature and properties
1332. Radio waves overview
1333. Radio waves properties
1334. Radio wave spectrum
1335. Radio-wave propagation
1336. Radio-wave propagation modes
1337. Radiowave Propagation
1338. Ray tracing models
1339. Ray tracing Optics
1340. RBN - Reverse beacon Network
1341. Real time propagation and band conditions
1342. Real-time activity of radio amateurs
1343. Real-time band conditions
1344. Real-time band conditions for ham radio
1345. Real-time data
1346. Real-time DX data
1347. Real-time DX propagation conditions
1348. Real-time DX reports * HF propagation prediction
1349. Real-time f0F2 map
1350. Real-time forecast of HF radio propagation
1351. Real-time ham band activity using the internet
1352. Real-time HF band conditions
1353. Real-time HF DX Propagation Prediction
1354. Real-time HF propagation charts
1355. Real-time HF propagation maps
1356. Real-time HF propagation prediction
1357. Real-time HF propagation reports (depending on ham band activities)
1358. Real-time HF propagation reports (ham activity and solar terrestrial data)
1359. Real-time HF Propagation Space Weather
1360. Real-time ionogram
1361. Real-time LUF Conditions
1362. Real-time maps and lists of ham radio activity
1363. Real-time MUF 3000 km propagation map
1364. Real-time MUF conditions
1365. Real-time MUF map
1366. Real-time NVIS map
1367. Real-time propagation and band conditions
1368. Real-time propagation charts
1369. Real-time propagation charts for HF radio ↗↗
1370. Real-time propagation conditions
1371. Real-time propagation maps and charts
1372. Real-time radio propagation maps
1373. Real-time radio propagation reports
1374. Real-time reports HF propagation
1375. Real-time reports of space weather
1376. Realtime skywave propagation reports
1377. Real-time solar flare
1378. Real-time space weather reports—Explanation
1379. Real-Time Sun & Moon Positions
1380. Real-time sunspots number
1381. Real-time watching of worldwide ham activity
1382. Real-time watching of worldwide hams' activity
1383. Reasons for Closed HF Bands
1384. Recent geomagnetic storms
1385. Recent geophysical & solar observations
1386. Recent Kp
1387. Recent LUF conditions
1388. Recent LUF map
1389. Recent LUF propagation
1390. Recent MUF distribution
1391. Recent observations - Geo (Terrestrial) & Solar
1392. Recent propagation conditions
1393. Recent R-S-G reports
1394. Recent solar flares
1395. Recent sunspots number
1396. Reciprocal HF propagation
1397. References—internet sources
      • Electromagnetic / Radio Waves properties ► Radio propagation references
      • Ionospheric Propagation references
      • NVIS unique mode of a skywave references
      • Gray line references
      • Propagation Indices references
      • Observations references:
        • Terrestrial magnetometers
        • The Sun
        • Space weather
        • Total Electron Content (TEC)
        • Real-time MUF
        • Propagation charts
      • Solar Phenomena references
      • Space weather phenomena references
      • Space weather references to agencies & services
      • Forecasting and prediction references
      • Tools and applications references for analyzing and forecasting HF propagation
1398. Reflection of radio wave compared to visible light
1399. Refraction of radio wave compared to visible light
1400. Refractive index maps
1401. Refractive index of HF radio in the ionosphere
1402. Regional and global online reports of HF propagation
1403. Regional conditions
1404. Regional HF conditions
1405. Regional MUF and solar indices
1406. Regional propagation
1407. Regional variations of HF propagation explained
1408. Regional variations of HF propagation report
1409. Regional vs. Global HF propgation conditions
1410. Regional vs. Global high frequency propgation conditions
1411. Regions of ionization
1412. Regions of band allocation (ITU region map)
1413. Region vs. Layer: Earth's Atmosphere and Ionosphere
1414. Remote sensing of the ionosphere
1415. Remote receivers, WebSDR and KiwiSDR
1416. Report skywave erratic propagation conditions
1417. Reporters of digital modes—references
1418. Reports of space weather
1419. Reports of Space Weather Conditions (SWx)
1420. Resources for Predicting HF Band Conditions for Ham Radio
1421. RF Basics: Radio Propagation
1422. RF coverage forecast software free
1423. RF coverage prediction software free
1424. RF path software free tools
1425. RF planning and optimization
1426. RF planning tools
1427. RF propagation forecast software
1428. RF propagation mapping software
1429. RF propagation prediction software
1430. RSG scales of Space Weather
 
S
1431. Satellites for space weather observations
1432. S1-S5 - scale of Solar radiation storms
1433. Schedule your QSOs today
1434. SDR spectrum
1435. SDR - Software Defined radio
1436. SDO - Solar Dynamic Obervatory (NASA)
1437. Seasonal phenomena
1438. Seasonal Effects on propagation
1439. Seasonal anomaly of HF propagation
1440. Seasonal & geographical variation of HF propagation
1441. Seasonal variations in HF radio propagation
1442. Seasons affect HF radio propagation
1443. Seeing HF Conditions in Real Time
1444. Selecting techniques for HF radio communication
1445. SEP
1446. Severe geomagnetic storm
1447. SFI
1448. SFI today
1449. SFU
1450. Short wave propagation
1451. Short-term forecast of HF radio propagation
1452. Short-term HF propagation planning
1453. Short-term prediction of HF radio propagation
1454. Shortwave Band Characteristics
1455. Shortwave listening (SWL)
1456. Shortwave radio frequencies — chart
1457. Shortwave propagation
1458. Shortwave propagation conditions
1459. Shortwave propagation conditions map
1460. Shortwave propagation forecast
1461. Shortwave propagation map
1462. Shortwave propagation prediction
1463. Shortwave radio propagation
1464. Shortwave radio propagation today
1465. SID - Sudden ionospheric disturbances
1466. Significance of solar activity for amateur radio
1467. Significant frequencies relevant to skywaves
1468. Significant geomagnetic storms in 2025
1469. Significat radio blackout events during 2024
1470. Simple Ham radio
1471. Skip distance | Skip distance—Skywave
1472. Skip zone
1473. Skip zone and skip distance
1474. Sky propagation advantages
1475. Sky propagation critical frequencies
1476. Sky propagation diagram
1477. Sky wave ionospheric propagation
1478. Sky wave or ionospheric propagation
1479. Sky wave propagation
1480. Sky wave propagation basics
1481. Sky wave propagation basics and tutorials
1482. Sky wave propagation definition
1483. Sky wave propagation diagram
1484. Sky wave propagation example
1485. Sky wave propagation frequency range
1486. Sky wave propagation PDF
1487. Skywave | Skywave / Skip—references
1488. Skywave at night
1489. Skywave concept
1490. Skywave Explained
1491. Skywave frequencies to listen to
1492. Skywave glossary
1493. Skywave HF radio propagation
1494. Skywave multi-refractions
1495. Skywave propagation
1496. Skywave propagation — what is it?
1497. Skywave propagation dynamics
1498. Skywave propagation—AI generated shortcast courtesy of Jean-Paul Suijs, PA9X
1499. Skywave propagation bad conditions
1500. Skywave propagation basics
1501. Skywave propagation charts
1502. Skywave propagation charts tutorial
1503. Skywave propagation conditions
1504. Skywave propagation example
1505. Skywave propagation for hams explained
1506. Skywave propagation for long-distance contact
1507. Skywave propagation for radio amateurs
1508. Skywave propagation forecast
1509. Skywave propagation frequency range
1510. Skaywave propagation indicators
1511. Skaywave propagation indicators for radio amateurs
1512. Skaywave propagation indicators for radio hams
1513. Skywave propagation indices
1514. Skywave propagation metrics
1515. Skywave propagation mathematical models
1516. Skywave propagation modes
1517. Skywave propagation odd conditions
1518. Skywave propagation PDF
1519. Skywave propagation review pdf
1520. Skywave propagation references
1521. Skywave propagation review
1522. Skywave propagation seasonal anomaly
1523. Skywave propagation secrets
1524. Skywave propagation today
1525. Skywave propagation tutorial
1526. Skyware propagation tutorial and practice
1527. Skywave Propagation YouTube
1528. Skywave radio propagation
1529. Software for HF propagation prediction
1530. Solar activity
1531. Solar activity and regions
1532. Solar activity is interfering with radio signals on earth
1533. Solar activity and ham radio propagation
1534. Solar activity & HF propagation
1535. Solar activity & HF radio propagation
1536. Solar activity affects HF propagation
1537. Solar activity affects skywaves
1538. Solar activity and HF propagation
1539. Solar activity and the ionosphere
1540. Solar activity chart over time
1541. Solar activity cycle chart
1542. Solar activity for radio amateurs
1543. Solar activity forecast
1544. Solar activity prediction
1545. Solar activity radio propagation
1546. Solar activity reports
1547. Solar conditions & ham propagation
1548. Solar conditions affect HF radio propagation
1549. Solar conditions and ham propagation
1550. Solar conditions and ham radio propagation
1551. Solar conditions and HF radio propagation
1552. Solar conditions for radio propagation
1553. Solar cycle
1554. Solar Cycle Ham radio
1555. Solar cycle radio amateur propagation
1556. Solar Cycle, status and progression
1557. Solar data
1558. Solar dynamics
1559. Solar Electromagnetic Spectrum
1560. Solar energetic Particle (SEP)
1561. Solar events
1562. Solar events live
1563. Solar flare alert
1564. Solar flare chart
1565. Solar flare forecast
1566. Solar flare history chart
1567. Solar flare interference comparison
1568. Solar flare radiation
1569. Solar flare radiation graph
1570. Solar flare warning
1571. Solar flares
1572. Solar flares and HF fadeouts
1573. Solar flares and HF Propagation
1574. Solar flares and propagation
1575. Solar flares and Radio blackouts
1576. Solar flares hitting earth today
1577. Solar flares today alerts warnings
1578. Solar flares classification chart
1579. Solar flux
1580. Solar flux chart for today
1581. Solar Flux Index (SFI)
1582. Solar flux index chart
1583. Solar flux indices: SF, SSN
1584. Solar flux index HF propagation
1585. Solar flux index today
1586. Solar flux outlook
1587. Solar Flux Today
1588. Solar flux value for today
1589. Solar Flux versus Sunspot Activity
1590. Solar Flux, Sunspots, and Ionizing Radiation
1591. Solar Ham
1592. Solar HF propagation chart
1593. Solar Indices: SSN, Solar Flux
1594. Solar indices and space weather | Solar Indices Explained
1595. Solar indices today
1596. Solar indices what are they?
1597. Solar index propagation chart
1598. Solar index today
1599. Solar maximum
1600. Solar minimum
1601. Solar observations
1602. Solar Particle event (SPE)
1603. Solar phenomena
1604. Solar propagation
1605. Solar propagation data
1606. Solar propagation ham radio
1607. Solar radiation
1608. Solar radio flux
1609. Solar radio interference
1610. Solar regions
1611. Solar regions and activity
1612. Solar region data - Sunspots
1613. Solar spectra
1614. Solar storm ham radio
1615. Solar storm radio amateur
1616. Solar storm today
1617. Solar storm warning today
1618. Solar storms (X-ray flares and particle events)
1619. Solar storms overview
1620. Solar storms consist of solar flares and Coronal Mass Ejections (CME)
1621. Solar storm FAQs: Your top amateur radio questions answered?
1622. Solar storms ham radio
1623. Solar synoptic map
1624. Solar terminator (i.e. Greyline)
1625. Solar terrestrial activity report
1626. Solar Terrestrial Data
1627. Solar terrestrial data explained
1628. Solar UV and X-ray spectral diagnostics (2018)
1629. Solar weather info
1630. Solar weather reports
1631. Solar wind
1632. Solar wind Ham radio
1633. Solar wind real-time dials
1634. Solar wind reports
1635. Solar X-Ray (Phenomenon)
1636. Solar X-ray Imaging system (SXI)
1637. Solar X-Ray flux levels
1638. Solar-terrestrial data and HF propagation
1639. SolarWx
< li>Space propagation | Space wave | Space wave propagation
1640. Space weather a comprehensive tutorial
1641. Space weather agencies & services Worldwide
1642. Space weather alerts
1643. Space weather and amateur radio
1644. Space weather and propagation
1645. Space weather and radio communications
1646. Space weather and radio propagation
1647. Space weather by solar ham
1648. Space weather data and plots
1649. Space weather effects on communication systems
1650. Space weather effects on communications systems (June 2020)
1651. Space weather events
1652. Space weather for Amateur Radio
1653. Space weather forecast
1654. Space weather for radio hams
1655. Space weather forecasting
1656. Space weather ground-based observatories
1657. Space weather ham radio
1658. Space Weather HF propagation
1659. Space Weather HF Radio propagation
1660. Space weather live
1661. Space weather models
1662. Space weather needs of the amateur radio community
1663. Space weather news
1664. Space Weather Nowcast
1665. Space weather observations
1666. Space weather observations from satellites
1667. Space weather overview
1668. Space weather phenomena
1669. Space weather prediction
1670. Space weather prediction center (NOAA)
1671. Space weather predictions for radio amateurs
1672. Space weather real-time 24hr effective sunspot number
1673. Space weather reports
1674. Space weather reports
1675. Space weather scales
1676. Space weather status and alerts
1677. Space weather warning
1678. Space weather warning system
1679. Space weather warning watch
1680. Space weather watch
1681. Space weather watches, warnings and alerts
1682. SPE
1683. Sporadic E (E_s)
1684. Sporadic E multipath
1685. Sporadic E propagation
1686. Spread F
1687. Sprites
1688. SSN
1689. Stanley article of the month (QST-June-2021)
1690. Stratosphere
1691. Sudden Ionospheric Disturbances (SID)
1692. Summary
1693. Sun flare propagation
1694. Sun flare radiation
1695. Sun spots ham radio today
1696. Sunspot cycle
1697. Sunspot index correlation
1698. Sunspot number
1699. Sunspot numbers explained
1700. Sunspots
1701. Sunspots and HF propagation
1702. Sunspots and skywave propagation
1703. Sunspots and solar flares
1704. Sunspots and sun flare
1705. Sunspots and solar flux
1706. Sunspots and the ionosphere
1707. Sunspots ham radio today
1708. Sunspots NOAA predicted sunspot number
1709. Sunspots number
1710. Sunspot number
1711. Sunspots number today
1712. Sunspots explained
1713. Sunspots
1714. Sunspots and solar flux
1715. SuperDARN
1716. Sunlight
1717. Sunspot cycles
1718. Sunspot index since 1750
1719. Sunspot index and long-term solar observations
1720. Sunspot number and radio flux
1721. Sunspot number forecast
1722. Sunspot number prediction
1723. Sunspot propagation chart
1724. Sunspot propagation effects
1725. Sunspots recent days
1726. Sunspot solar cycle 25
1727. Sunspots today
1728. Surface wave propagation
1729. SWPC = Space Weather prediction center (NOAA)
1730. swx — Space Weather Conditions
 
T
1731. T Index concept
1732. T Index map
1733. Table of frequency allocations chart
1734. TEC—Total electron content
1735. Telecommunication Circuit
1736. Telecommunication circuit illustration
1737. Terminator line
1738. Terrestrial geomagnetic indices
1739. Terrestrial observations
1740. The anatomy of a radio signal
1741. The art of HF Frequency Selection
1742. The Basics of HF Progagation
1743. The Big Gun`s Guide to Low Band Propagation: A book by Bob Brown, NM7M (2002)
1744. The current conditions on ham bands
1745. The current propagation conditions
1746. The decline and comeback of skywave HF radio
1747. The effects of weather on amateur radio propagation
1748. The effective ham radio range
1749. The electromagnetic spectrum
1750. The Fast Track to Understanding Ham Radio Propagation
1751. The HF bands assigned to hams
1752. The HF bands assigned to radio amateurs
1753. The HF bands
1754. The HF bands for newcomers
1755. The Holy Cluster
1756. The impact of geomagnetic storms on HF propagation
1757. The importance of frequency management in HF radio communications
1758. The influence of ionospheric electron density fluctuations on HF propagation
1759. The ionosphere
1760. The ionosphere and HF propagation
1761. The ionosphere and skywave propagation
1762. The K-Index and Amateur Radio
1763. The Little Pistol's Guide to HF Propagation by Bob Brown, NM7M, Worldradio Books (1996)
1764. The lowest usable frequecy
1765. The Magic of Aurora
1766. The magnetosphere
1767. The maximum range of ham radios
1768. The most significant blackout event of the 25th solar cycle May 2024
1769. The mystery of HF propagation
1770. The path of wireless communication
1771. The propagation of radio waves
1772. The radio spectrum
1773. The Rebirth of Shortwave radio communication
1774. The rebirth of skywave HF radio
1775. The recent propagation conditions
1776. The recent sunspots number
1777. The relationships between sunspot number and solar radio flux at 10.7 centimeters
1778. The science behind radio wave propagation
1779. The solar cycle | SSN Explained
1780. The solar cycle and sunspots
1781. The Sun and solar activity
1782. The Sun and space weather
1783. The Super Dual Auroral Radar Network (SuperDARN)
1784. The Structure of the Ionosphere
1785. Theory-Based Tutorial on HF Propagation
1786. Thermosphere
1787. TID (Traveling ionospheric disturbances)
1788. Time of day
1789. Time-of-day band selection
1790. Total Electron Content (TEC)
1791. Tools and Applications
1792. Tools and Applications for Monitoring HF Band Conditions
1793. Tools for analyzing and forecasting HF propagation
1794. Total electron content (TEC)
1795. Tracking digital modes
1796. Tracking global beacons
1797. Transmission Angle
1798. Traveling ionospheric disturbances (TID)
1799. Transient Luminous Events (TLEs)
1800. Troposphere
1801. Tropospheric propagation
1802. Tutorial and practice on skywave
1803. Tutorial and practice on skywave prediction
1804. Twilight zone
1805. Types of radio wave propagation
 
U
1806. Ultraviolet
1807. Understanding amateur radio bands
1808. Understanding amateur radio NVIS
1809. Understanding and Using Propagation Tools to Plan Your QSOs
1810. Understanding Band Conditions Banners
1811. Understanding current HF band conditions
1812. Understanding geomagnetic indices
1813. Understanding ham bands closed
1814. Understanding ham band conditions banner
1815. Understanding ham band propagation
1816. Understanding ham radio bands
1817. Understanding ham radio frequencies
1818. Understanding ham radio propagation
1819. Understanding ham radio propagation techniques
1820. Understanding HF Propagation: A Review
1821. Understanding HF Propagation: All in One
1822. Understanding HF Propagation for radio hams
1823. Understanding HF propagation numbers
1824. Understanding HF propagation practice
1825. Understanding HF radio propagation
1826. Understanding HF propagation reports
1827. Understanding HF radio systems
1828. Understanding HF skywave propagation
1829. Understanding ionosphere
1830. Understanding K-Index Impact on HF Propagation
1831. Understanding LF and HF propagation, G0KYA, G3NYK, RSGB (2010)
1832. Understanding LUF and MUF
1833. Understanding NVIS
1834. Understanding of Ham radio propagation
1835. Understanding of HF radio propagation
1836. Understanding Propagation of Radio Waves
1837. Understanding Propagation of Skywave
1838. Understanding propagation numbers
1839. Understanding propagation: How space weather affects radio waves
1840. Understanding Propagation: Paul L. Herrman, N0NBH (11-July 2010)
1841. Understanding Propagation: M. Landress, WB5ANN, April 2022
1842. Understanding radio communication systems
1843. Understanding radio propagation
1844. Understanding radio propagation: A graphical perspective
1845. Understanding Radio Waves
1846. Understanding radio waves and their frequencies
1847. Understanding RF propagation: Types and properties
1848. Understanding Radio Waves: Nature and Properties
1849. Understanding Radio Waves and their Frequencies
1850. Understanding Radio Waves: Nature and Properties
1851. Understanding solar storms and how they impact ham radio
1852. Understanding the basics of radio propagation
1853. Understanding skywave propagation
1854. Understanding solar activity and its impact on HF propagation
1855. Understanding solar indices
1856. Understanding space weather indices
1857. Understanding the basics of HF band conditions
1858. Understanding the band conditions banner
1859. Understanding the HF band conditions
1860. Understanding wavelengths and frequencies in ham radio
1861. Usable Frequency Range: from LUF to MUF
1862. Usable HF frequencies
1863. Uses of radio waves
1864. Using HF beacon tracking programs
1865. Using VOACAP for HF radio propagation predictions
 
V
1866. Validation of HF propagation models
1867. Variations in HF radio propagation
1868. Visualizing HF propagation
1869. Verification of HF propagation models
1870. Very High frequency (VHF)
1871. Very Low frequency (VLF)
1872. VHF propagation map
1873. View HF bands conditions at a glance
1874. Virtual height in wave propagation
1875. Visualizing HF propagation
1876. Voacap HF path prediction maps
1877. VOACAP online
1878. Voacap online HF predictions
1879. VOACAP prediction
1880. VOACAP propagation planner
 
W
1881. Watch Out for Geomagnetic Storms
1882. Wave attenuation and absorption
1883. Wave propagation
1884. Wavelength and Frequency
1885. Wavelength and Propagation
1886. Weather influence on HF radio propagation
1887. WebSDR
1888. What affects HF radio signals?
1889. What affects radio signals?
1890. What affects radio wave propagation?
1891. What are band conditions?
1892. What are band conditions banners?
1893. What are DX clusters?
1894. What are electromagnetic waves?
1895. What are geomagnetic disturbances?
1896. What are geomagnetic indices?
1897. What are geomagnetic storms?
1898. What are ham band conditions?
1899. What are ham bands?
1900. What are ham radio frequency bands?
1901. What are HF band conditions?
1902. What are HF band propagation conditions?
1903. What are ionospheric clouds?
1904. What are ionospheric conditions
1905. What are ionospheric effects?
1906. What are ionospheric models?
1907. What are LUF and MUF?
1908. What are MUF and LUF?
1909. What are propagation indices?
1910. What are radio blackouts?
1911. What are radio waves?
1912. What are radio waves and how do they travel?
1913. What are solar flares?
1914. What are solar storms?
1915. What are space weather scales?
1916. What are sprites in Earth's atmosphere?
1917. What are sunspots?
1918. What are the amateur radio HF band conditions?
1919. What are the basic wave propagation mechanisms?
1920. What are the causes of Sporadic E?
1921. What are the current conditions on ham bands?
1922. What are the current HF propagation conditions?
1923. What are the current shortwave propagation conditions?
1924. What are the disadvantages of HF radio?
1925. What are the different types of ionospheric propagation?
1926. What are the factors affecting HF propagation?
1927. What are the factors affecting ionospheric conditions?
1928. What are the factors affecting skywave propagation?
1929. What are the geomagnetic indices?
1930. What are the ham radio HF band conditions?
1931. What are the HF ham bands?
1932. What are the modes of HF-radio propagation?
1933. What are the modes of radio propagation?
1934. What are the R-S-G scales in space weather?
1935. What are the regions of the ionosphere?
1936. What are the solar indices?
1937. What are the sources of medium and large scale traveling ionospheric disturbances?
1938. What are the three modes of HF-radio propagation?
1939. What bands and modes will give me voice at 5,000 kilometers?
1940. What Bands Are Open Now?
1941. What can we expect from a HF propagation model?
1942. What causes HF propagation conditions to vary periodically in a 27-day cycle?
1943. What causes ionospheric ionization?
1944. What causes the ionosphere to form?
1945. What controls HF propagation under normal conditions?
1946. What do propagation indices mean?
1947. What does it mean when a band is closed?
1948. What does NVIS mean?
1949. What effect does the change of seasons have on HF propagation?
1950. What every ham needs to know about skywave propagation
1951. What does a Grey line mean?
1952. What does the Solar Flux Index mean?
1953. What factors influence HF radio propagation?
1954. What frequency should I use for ham radio?
1955. What ham radio band should I use?
1956. What HF bands are allocated for radio amateurs?
1957. What HF bands are closed now?
1958. What HF bands are open at night?
1959. What HF bands are open now?
1960. What HF frequency should I use?
1961. What impact do solar phenomena like sunspots and solar flares have on radio communications?
1962. What important quality does the ionosphere have?
1963. What is a geomagnetic storm?
1964. What is a good app or website to see HF propagation?
1965. What is a skywave propagation?
1966. What is an electromagnetic (EM) wave?
1967. What is Earth's magnetic field?
1968. What is earth Magnetosphere?
1969. What is fading?
1970. What is Geomagnetic Activity?
1971. What is Geomagnetic Disturbance?
1972. What is ham radio?
1973. What is ham radio and how does it works?
1974. What is ham radio communications?
1975. What is ionization?
1976. What is ionospheric propagation?
1977. What is Grayline propagation?
1978. What is Hale cycle?
1979. What is Ham radio propagation?
1980. What is HF propagation?
1981. What is HF radio propagation?
1982. What is HF radio propagation prediction?
1983. What is HF wave propagation?
1984. What is high-frequency (HF) radio?
1985. What is ionization?
1986. What is K index?
1987. What is LUF?
1988. What is MUF?
1989. What is NVIS?
1990. What is plasma?
1991. What is radio?
1992. What is radio propagation?
1993. What is radio spectrum
1994. What Is radio wave propagation?
1995. What is RF propagation
1996. What is sky propagation?
1997. What Is sky wave propagation?
1998. What Is Skywave propagation?
1999. What is solar activity?
2000. What is solar cycle? | Solar cycles: A tutorial
2001. What is solar wind?
2002. What is space weather?
2003. What is the 80 meter band?
2004. What is the bandwidth of HF radio?
2005. What is the best HF band for daytime?
2006. What is the best HF band for DX?
2007. What is the best time for the 40 meter band?
2008. What is the best time of day for HF frequencies?
2009. What is the best time of day for HF radio?
2010. What is the composition of the ionosphere?
2011. What is the current HF propagation?
2012. What is the current LUF?
2013. What is the current MUF?
2014. What is the current lowest usable frequency (LUF)?
2015. What is the current shortwave propagation conditions?
2016. What is the current skywave propagation conditions?
2017. What is the dead zone in radio communication?
2018. What is the difference between solar proton flux and solar proton density?
2019. What is the difference between Greyline and the Solar Terminator?
2020. What is the difference between Global versus Regional HF propgation conditions?
2021. What is the difference between earth Magnetosphere and Earth's magnetic field?
2022. What is the difference between geomagnetic and ionospheric storms?
2023. What is the difference between solar indices and propagation indices?
2024. What is the D region of the ionosphere?
2025. What is the E region of the ionosphere?
2026. What is the F region of the ionosphere?
2027. What is the farthest a ham radio can reach?
2028. What is the K index for propagation?
2029. What is the longest range 2 way radio?
2030. What is the lowest usable frequency?
2031. What is the LUF frequency?
2032. What is the max radio range?
2033. What is the maximum usable frequency?
2034. What is the most popular ham radio mode?
2035. What is the range of a 100 watt ham radio?
2036. What is the rule of thumb for HF frequency?
2037. What is the skip zone?
2038. What is the solar cycle?
2039. What is the solar index?
2040. What is the structure of the ionosphere?
2041. What is the T Index?
2042. What is Total Electron Content? TEC
2043. What is virtual height?
2044. What is your favorite propagation prediction tool?
2045. Where can I find solar data?
2046. What radio waves actually are?
2047. What the numbers mean in propagation
2048. What to expect from our HF amateur radio bands?
2049. When are HF bands closed?
2050. When will HF band conditions improve?
2051. Which Ham Band is Open Now?
2052. Which ham bands are open now?
2053. Which HF bands are best during the day and which are better at night?
2054. Which ionospheric region is closest to the Earth?
2055. Why are bands bad?
2056. Why are ham bands closed?
2057. Why do we need propagation forecasting?
2058. Why do we need propagation forecasts?
2059. Why forecast HF conditions?
2060. Why is a band closed?
2061. Why is a radio band closed?
2062. Why is HF propagation so poor?
2063. Why is HF used for long range communication?
2064. Why is propagation on shortwave (HF) terrible right now?
2065. Why is shortwave used for long range communication?
2066. Why is there no activity on the HF Radio?
2067. Why Use Propagation Tools?
2068. Wide-band WebSDR
2069. Window of usable frequencies: from LUF to MUF
2070. Wireless Communication Circuit
2071. Wireless communication concept
2072. Wireless transmission concept
2073. Working The Gray Line
2074. Worldwide LUF map
2075. Worldwide MUF chart
2076. WSPR - Weak Signal propagation reporter * WSPR Live * WSPR Rocks
2077. WSPR - Weak Signal Communication—references
2078. WSPR - Weak Signal Propagation Reporter—references
2079. WSPRnet
 
X
2080. X-ray flares review
2081. X-Ray flares what are they?
2082. X-Ray Flux Levels Now
2083. X-Ray Flux Levels Scale

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2084. 6 meter propagation map
2085. 10 meter propagation map
2086. 12 meter propagation map
2087. 15 meter propagation map
2088. 17 meter propagation map
2089. 20 meter propagation map
2090. 30 meter propagation map
2091. 40 meter propagation map
2092. 60 meter propagation map
2093. 80 meter propagation map
2094. 160 meter propagation map
2095. 24-hour HF propagation forecast

Total visits since 17 August 2022.
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The number of visits (graphs displayed below) peaked during HF propagation disruptions.

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Hourly visits today

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