[Kenwood] TS-2000 HF/VHF 2SC1972 base voltage?

Fri Jul 25 13:28:22 EDT 2014

On 25 Jul 2014 at 12:03, Roger Shultz wrote:
> I was asked by a friend to repair his TS-2000X and found that both 2SC1972
> driver transistors were leaky resulting in no power output on HF and 2
> meters. 
>> I've replaced both devices, set the idle currents as shown in the service
> manual and then checked base voltages on both Q3 and Q4. The Service Manual
> shows .74 volts on each base but I'm only reading about .25 vdc with my DVM.

First of all, do you know what test instrument was used to provide the original 
values? Secondly, most DVMs do NOT provide accurate readings if there is 
RF present. Thirdly, have you simply tried the rig out to see if the output is 
now correct?
If the rig now works whereas it did not before, then I would suspect that your 
instrument is the reason you are, apparently, getting a reading that appears 
to be too low.
> Am I missing something or is this reading satisfactory? Before the devices
> were changed I was reading 3.0 vdc on each base which was clearly wrong.

Indeed!
Ken W7EKB