- Vibroplex Adjustment, Cleaning and Sending Technique - by David J. Ring, Jr., N1EA GOOD BUG SENDING TECHNIQUE Your wrist is "rocked" with the same motion that you use when opening a door knob, the wrist and are lie on the desk and rock with that motion. The position in which you assume to use the bug would be just like you would grab a door knob or to receive a beverage bottle. You roll your wrist on the fleshy part of your hand back and forth. No finger movements at all! Finger motions are not to be used as they give carpal tunnel syndrome (glass arm) the idea is to rock the wrist with a bug and cootie key. Unfortunately the paddle used with an electronic keyer must be tapped with fingers at high speeds :( I know it might be silly to say this, but it is much easier to send when both feet are on the floor not angled to the left or right, but straight and senders body is straight and not turned. It is much easier - try it if you don't believe this. BUG CLEANING The following is time consuming but I find it always works and I do this routinely and it takes time but it saves time because it eliminates problems. If your bug is old, take it completely apart and clean (especially) the contacting surfaces, including the underneath connecting strips (especially around the screws), the countersunk hole for the grounded binding post, the silver contacts, the surface where the U shaped dot spring contacts the vibrator, and the two beveled pins of the trunnion assembly (the pins on which the main lever pivots in the frame), and make sure that the cups into which the pins fit are clean of debris. I use the cotton wadding with metal polish which is sold nationwide, and a stick pencil type eraser to clean the more stubborn parts and then use Flitz metal polish to finish the metal cleaning. If you have an ultrasonic cleaner (jewelry cleaner) put some ammonia and water in it, with a few drops of Dawn dish cleaner liquid and use for 15 minutes, then repeat with clean water. I dry everything in a toaster oven for 1 hour at 140 degrees F. A bug has to swing far enough to compress the U spring - it doesn't send like a paddle - you use your wrist - you shouldn't get tired with this key - if you are, your probably doing it incorrectly. The dash spacing and tension should be adjusted for reliable dashes. See the "Art and Skill of Radiotelegraphy" by N0HFF available several places and in several languages on the Internet for good advice on sending and general tips. CONTACT ALIGNMENT Old bugs have a screw which holds the lever against the trunnion post. This can be adjusted up and down. Later bugs do not, and the alignment of the dot contact and the dash contact must be done by adjusting the top and bottom trunnion screws. The bottom trunnion screw is held fast (and will strip unless this screw is loosened) by a screw on the rear side of the frame. You must use a long handled screw driver to get to this screw! Loosen this screw and you will be able to loosen and tighten the bottom trunnion screw and raise and lower the position of the lever. The lever should be adjusted so that the height of the lever / mainspring / vibrator assembly is such that the contact on the U shaped dot spring is vertically aligned with the dot post contact. The alignment of the dash contact can be done (after the above is done) by loosening the small contact plate and adjusting. All final adjustments should be done so that the contacts are touching and completely aligned so that the contacts meet as fully and directly as possible. DOT ADJUSTMENT Bugs used for radiotelegraphy vs bugs used for landline telegraphy were set to approximately 60% of an analog VOM meter full-scale reading in resistance. Put the meter on OHMS, adjust for full scale, then start a series of dots, and adjust for about 60% full scale - there usually is a logging scale on the VOM meter. Digital won't work but an o'scope will work but adjust for more than 1:1 ratio to work well for radio work. Landline telegraph was 1:1 or a bit less. If your power is 1500 watts key down, it will still be 1500 watts on each dot closure - but the dots will give different meter ballistic movements different results - but rest assured they are still full power. That being said, dots with a dot/space ratio of about 100:60 OR 1.67:1 will give better copy than dots with a 1:1 ratio during radio conditions on typical hf bands. Or instead of 1.00 to 1 - dots sound better about 1.5 to 1.67 to 1. CONTACTS If you buy some silver cleaner you can clean them. If you can find 1500 grit wet/dry sandpaper, you can smooth them out. You can also buy a burnishing tool from GC Electronics for $1.57 which is an extremely fine file that is about 1/4 inch wide and about 1/32 inch thick which was designed especially for that purpose. I use 800 grit wet/dry sandpaper (very lightly and with care) then 1500 grit wet/dry and finally I polish with Flitz metal polish which is a very very low grit polish;. The contacts if done this way will come out like mirrors. Vibroplex sells a contact cleaner that is a narrow long strip of fine crocus cloth folded back on itself and glued together. It works very nicely. You can make a bunch of them by taking a piece of contact paper, folding it in half, then putting rubber cement (from Office Supply store or bike shop) and putting a heavy large book on it until it dries. Cut into 1/2 inch strips the narrow way. To use hold the contacts together with your hands (be very careful of the fragile dot contact spring!) and rub in and out by drawing and pushing the strip through the held closed contacts. Metal polishing the contacts. Simachrome is nice, but Flitz is much better. I have a brass based Scotia paddle that I hand polished to a mirror finish with Flitz two (1998) years ago. It is a mirror and it is as golden as the day I polished it - which is simply amazing. Flitz has an anti-corrosive in it. You MUST clean the contact after using polish and it is recommended that you clean it after using a Vibroplex cleaning strip. I use isopropal alcohol 91% for this as water around a Vibroplex is not nice as it can creep into where it will rust the base or screws. I bought a 5% spray De-Oxit as an experiment as it was quite costly. It so impressed me that I bought the 100% pure product (even more costly but per "unit" of percent, much cheaper. I swear by it. The contasts last nearly *forever* but being near salt water (800 feet) they do go bad within six months. BUG ADJUSTMENT Old-timers insisted upon sizable gaps. In fact, a significant gap for the dit lever moved against a significant spring resistance sets up a good vibration of the mainspring for producing dits and avoiding scratchy and bouncing dots. The limit screw adjustment for the damper is adjusted just so the end of the swinging pendulum contacts the damper. The bug is also quieter when the damper doesn't move as dramatically. The dot spring will have more tension than you might be accustomed to. The spring tension returns the lever after sending dots quickly and it also makes the lever move with more force which sets up a stronger impact on the dot spring which results in much stronger and less problematic dots. This is the cure for poor dots if the contacts and the other connections are clean. HARD TO FIND PROBLEMS When you have bad dots, the hard to diagnose problems that I've routinely found are: The terminal connectors are loose and the round cylinder shaped nut is not holding the base tightly when the bug sends dots the contact is intermittent. The dot spring is loose on the vibrating arm. When the contacts crash, the spring conducts intermittently. Similar happens for all the contact path on the connecting straps - if one is loose or corroded, it will produce poor dots. 73 David J. Ring, Jr., N1EA Former Commercial Radiotelegrapher