[R-390] Gear train rebuild..
Pete Williams
jupete at internode.on.net
Wed Jul 13 22:15:00 EDT 2016
A couple of tips from experience..... not extensive but having relied
on the Y2K-3 reference, thought this might be a useful addendum
Also saves a great volume of cussing.
1. Before reassembly set the Geneva drive to the 07 +007 position per
drawing in manual. Check the wafer contacts on the band switch to agree
with the pics for the 7 Mhz position.
2. Keeping the 8-16Mhz shaft in position when fitting the other
gears is a pain. I've used a small bolt ,washer and nut thru the
cam hole at the rear of the RF module holds it in place for the
duration and on its mark. ---Check tho'
3. Fitting the other gears while maintaining the 2 tooth stretch of
the split gear also a pain. I do the 2 tooth stretch and use a short
piece of fine wire thru' and around the teeth and twist to hold the
alinement. Keep the clamps positioned for ease in tightening when
doing the final check/cam setting. The wire can be cut off at this
time too.
4.Fitting and mating the gears while tied now is much easier. Don't
tighten the clamps on the shafts but just enough to stop gears
moving from their adjacent alinement setting. Don't try to hold the
shafts to their marks--- sort this at the end.
RF MODULE ... T 204 4 - 8Mhz antenna xfmer/assy
With a seeming increase in these radios and assemblies coming on the
scene, it would be wise to check that front end coil.... For what
ever reason, previous users either private , mil/navy managed to get
large amounts of RF into the
front end.
The most recent one I did had the primary fibre former and wire
completely carbonised. This would make it the 4'th I've encountered
over the years so apparently that frequency range the most popular in
high power circles.
Thanks to those who have gone this route before and authored such a
fund of knowledge.
Cheers
Pete VK3IZ
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