SSTV

"A picture is worth a thousand words"

Sight is our best used sense and the primary source of information about our soundings. What would our daily life be like with out it? Sending SSTV images is a great way to enhance Amateur Radio communications. In the past only a few Amateurs enjoyed SSTV. There was very little commercial equipment and it was quite expensive. Home brewing was too complicated for most people. This situation has changed drastically in the past years. Rather than using expensive special purpose hardware, newer systems are using personal computers to do the work. There is a wide assortment of software that uses very simple interfaces, ready-to-use commercial systems and home brew projects to fit every budget. Most systems now use a simple interface that connects the radio to your computer's sound card. New people are showing up on SSTV everyday.

Modes
Frequencies
Interface
Edict
Links
Pictures

Popular SSTV Modes

Family	Name	Type	Time (sec)	Lines	Notes
Robot	8	B&W	8	120	A
	12	B&W	12	120
	24	B&W	24	240
	36	B&W	36	240
	72	Y&C	72	240
Wraase SC-1	24	RGB	24	128	C
	48	RGB	48	256	B
	96	RGB	96	256	B
Martin	M1	RGB	114	256	B
	M2	RGB	58	256	B
	M3	RGB	57	128	C
	M4	RGB	29	128	C
Scottie	S1	RGB	110	256	B
	S2	RGB	71	256	B
	S3	RGB	55	128	C
	S4	RGB	36	128	C
	DX	RGB	269	256	C
AVT	25	RGB	24	120	D
	90	RGB	90	240	D
	94	RGB	94	200	D
	188	RGB	188	400	D
	125	B&W	125	400	D

Types: B&W = Black and White. Y&C = Colour as luminance and chrominance. RGB = Colour as red, green and blue components.
Notes: A - Very similar to the original 8-second SSTV standard. B - The top 16 lines are always sent as grey scale, so 240 lines are usable. C - The top 8 lines are always sent as grey scale, so 120 lines are usable. D - AVT modes have a 5-second digital header and don't use horizontal sync.

What frequencies are used?

Some countries are more restrictive, but in Canada and the U.S. SSTV can be used anywhere voice is allowed. Traditionally, these frequencies are used:
· 3.845
· 3.857
· 7.171
· 14.230
· 14.233
· 21.340
· 28.680
· 145.5 MHz
20 meters is generally your best bet for finding activity. 80 meters is also popular. Recently, most of the growth has been on 2 meters.

The Interface

These are only some of the interfaces available. They can operate SSTV but they can also work other modes.
- RIGblaster
- BayPac MultiMode
- MFJ 1278
- Far Circuits - A Flexible Digital Mode Interface by Mitrenga, QST Nov 00 (A build it your-self project.)
There are many schematics and circuit designs on the Internet.

Slow Scan Edict

Remember - A picture is worth a thousand words. Many people maybe receiving the pictures you send.
1. Before starting to TX a picture on a frequency, ask in PHONE "Is this frequency in use?" Never transmit if you hear any other signals.
2. Never interrupt a SSTV QSO by sending a picture. See #1
3. The suggested spacing for SSTV frequencies 3kHz.
4. Don't hesitate to help station operator who does not have the right operating procedure. They may not even know about it.
5. Try to be original in your pictures! Station related pictures (shack, antennas, QTH, area, family etc) make SSTV really attractive! Please don't transmit pictures containing Porno, politics, commercials etc.
6. SSTV is a lot more than a picture. Take time to talk about your pictures between sending. Give out comments about the pictures that you receive.
7. Before you transmit your picture, ask the receiving station if they are ready.
8. When you would like to answer to a CQ, first ask the CQ'ing station in PHONE if they are ready for your picture.
9. 20 meters is really overcrowded (and not only with SSTV!). Try the higher bands.