[ICOM] Fwd: IC-751A USB problem

[Jaime Gomez]

Hi Icom friends,

I have a friend´s (HK1F) radio - an IC-751A - with a strange problem. It
receives  and transmits OK on all modes and frequencies, but in USB. In
USB the Rx frequency is OK - I have checked transmitting with my IC-781 and
it receives right on frequency - but when I transmit with the 751A its
output frequency moves down 2 KHZ. I do not have the XIT activated.

I did PLL and Frequency alignment as per the service manual and found the
USB BFO fequency out of range. I replaced the trimmer C202 and the frequency
is now right as per the manual and it does not change between Tx and Rx.

I adjusted the PBT and there is no change in frequency between Tx and RX. I
do not know what else can I check to find why that change of frequency in
USB transmission.

Appreciate any hint, thank you and 73


-- 
Jim, HK1N