[Yaesu] HELP needed to un-CB a FT-902DM and restore 10M operation

Wed, 3 Apr 2002 11:54:48 EST

Bought a nice FT-902DM at a ham fest a year ago that works great, except no 
10M. ( The rig came with CB xtals in place of the 10M A-B-C-D xtals in 
the Xtal Oscillator and works fine on CB freqs but only allowed me to tune 
a few khz of 10M....to around 28.050. )
SO, the solution seemed simple enough. I purchased the proper 10M xtals 
and installed them.
BUT, the new xtals wont oscillate. ie The rx is dead on 10M band switch 
settings A, B, C D and wond tune... it just floats at some freq between 25. 
something and 27. something depend on the band switch setting. 
Since the only adjustment in the XCO is a coupling xfo, I adjusted it 
...but to no effect.
Then on a lark I moved the 10A xtal to the 10D slot, and bingo! it worked, 
but only from 28.0 to 28.177 mhz then it stalls on that freq and wont tune 
any higher. Tweaking the coupling xfo has a minor effect-.if I tweak it too 
much, the xco stops oscillating. But it doesnt add any tuneable bandwidth .
Any suggestions on where I go from here? 
The rig works fine otherwise. Output is a little low on some bands even with 
new tubes, but then, I cant perform a complete alignment cuz I cant get it 
to oscillate above 28.177, and the starting point for a complete alignment 
is at 30 mhz. 
Help would be greatly appreciated. 
Any techs out there who have made similar modifictions adn can tellme what to 
look for?
Bob