[Fox_Tango] FT-901/902 question

[Dr. Gerald N. Johnson]

On Wed, 2009-01-07 at 23:16 -0800, Steve Sutfin wrote:
> Hello to the list,
>   In the service manual for my FT-901DM I have wondered why the 'parts 
> layout' for the VCO and XTAL units show 'additional' circuitry ( Q1213 
> & T1209 etc. on the VCO unit and Q1311 & T1311 etc. on the XTAL unit) 
> but nothing shows on the schematic. The respective boards are marked 
> for those components but nothing is there.
>    I also have a 'parts' radio and the same boards in that have all the 
> components installed including the xtal socket.
>   Anyone have a clue what this 'extra band' might be? I swapped the 
> boards and put in a 10 meter crystal and got PLL lock on 34.xxx MHz or 
> so with the bandswitch below the 15 MHz WWV position. I thought maybe 
> it was for the CB band but I think that is a set of four that replace 
> the 10 meter crystals.
>   Anyway, it would be fun to find out what the circuit is /was for. 
> Anybody...........????
> 73,
> Steve k7dna
> 
There was a kit to add WARC bands to the 901DM. It wasn't known much.
The first one enabled would have been 10 MHz, then 18 and 24 MHz later.
With some parts in the radio, the kit may have mostly been crystals,
I've never seen it or been inside a 901DM. I'm sure it wouldn't be
difficult with the manual in hand to figure out the appropriate crystal
frequencies for 10, 18, and 24 MHz bands or cheat by looking them up in
a 902 manual.

73, Jerry, K0CQ