The FT102 is quite a good rig BUT........
1. The key clicks on most of the various production series are such that it is
unfit for human consumption. That can be cured. Yaesu's mod for this still
leaves awful performance.
2. You need a matched set of three PA tubes. (that can be cured with a separate
bias pot for each tube)
3. The handbook circuits, maintenance handbook PC board layouts, and the radio
you have may not match up.
4.Some variants have an 'anti flash over diode' in series with the PA screen
grid feed. An ideal way to get run away in PA plate current when the tubes age.
5. As it comes, the 'CW' position gives SSB selectivity, while 'CW Narrow'
cascades all the CW filters. This is easy to cure to give something like 800Hz
wide in CW and 250Hz in CW Narrow. (assuming you have the filters!)
6. There are receive spurs on 3.5 and 7.0 in the CW bands. A strong signal on
around 3500 - 3501 just blasts through even when you're tuned up at 3505. This
too is fixable, but you have to be prepared to be rather brave as you rip bits
out, and refit other parts!
7. The relays in the front end suffer from oxidation and tarnishing, especially
when used by operators who smoke. That can be cured with few resistors to bleed
some DC through the contacts from the 24 volt line: this breaks the oxide film,
and is easier than changing the relays.
8. A number of the ICs used in the counter and synthesiser are now obsolete, and
expensive. The custom IC in the VFO is made of 'unobtainium': so is the display.
I suppose my qualification of it as a good rig really means 'after you've dealt
with these problems, it's a good rig!'
On the plus side, the minimal level of integration means that it's maintainable,
since you can always get around failures, although it might take a lot of
effort. You're not stuck with a failed, unobtainable custom ASIC that kills the
rig. All the various reviews have given it very high marks on its phase noise
performance, although looking at the circuits, I cannot for the life of me see
why it is as good a performer on phase noise as it is. It's renowned for getting
good audio reports, too.
I still haven't found anything good enough for me to consider getting rid of
mine - especially since I've fixed the above problems!
73
Peter G3RZP
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