[Premium-Rx] Collins 2050 help please

[Paul Wende]

Hello fine group,

After a 15 month hiatus, to stop and have a baby, I am now getting back into
the radio scene and have acquired another 2050, which of course has a
problem. I made the mistake of giving my wonderful manual from Walter away
with the last radio so I need two things. Does anyone still have a depot
level service manual they would like to sell, and number two, the problem
with the radio.

It's pretty basic, push the power button, the fault light comes on
immediately, the power supply growls and there is absolutely no display or
speaker noise. To me, this points to power supply, which I checked, and it
looks like someone may have been in there as the trim pot on the 5V supply
was set to 3VDC, I turned it to make it 5 and the power supply seems okay,
with all voltages correct. I measured the 5V draw at 2.5 amps, which seems
reasonable.
Side note, the construction of this power supply is certainly second rate,
compared to the build quality of the radio. Looks like someones high school
project. :-)

Until I get schematics, I am flying blind, which I really don't wish to do
with this rig as it is in mint condx. and I don't wish to go blindly
desoldering things, looking for the trouble.

Anyway, any help would certainly be appreciated. Has anyone scanned the
schematics to a PDF file yet? Any other suggestions? I started checking the
tantalums as I know they can be problematic but every one I tested seemed
okay.

Kind regards,

Paul Wende
VE7KHz