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Kamakiri,
unfortunately I do not have a DTV converter handy, so I can't try any of the Buffalo stations...
I've added a reference shot on how the same channel is looking on a 4:3 Sony video monitor I use for testing,
the signal is coming from the same box though using the RCA outputs.
So, I've looked at the horizontal board, and everything there looks peachy...
Replaced one small electrolytic that was showing 3.2uF instead of 4.7 but I doubt that will affect anything.
Also replaced the main PS filter cap that was showing 430uF instead of 470 with one I had on a board in my salvage boards box,
it was the same diameter as the old one so I thought why not, couldn't hurt (the replacement was measuring perfectly at 471uF).
I'm also adding a few clearer pics of the PS board, including the back of the plate it sits on that also holds the regulator and the 130 Ohm
sand resistor that sits in line with it, as well as a closeup of the R3249 resistor that supposedly drifted...
Well yea the value is odd, but the color bars look fine to me, so idk, the resistor doesn't look overheated.
All electrolytic in the PS and Horizontal board test just fine... (I use a capacitor tester).
Zeno,
I've done the brightness test as I mentioned above, and the B+ changes by about 2 volts, the picture changes in size for a split second
when I turn the the brightness all the way up but right away corrects itself properly, so I assume the 2V drift is not very significant,
correct me if I'm wrong though.
Inspecting the PS up close, I can notice that the STR has been removed and perhaps replaced in the past, as well as the resistor
in line with it (thermal paste smears and fingerprints around the STR, and soldering that doesn't look factory on the resistor...)
I am suspecting that the replacements might not have been the exact parts?
Another thought I have in mind is replacing the STR380 with an STR370 that I have here on hand, that should lower the B+
to 110V instead of 123V where it sits right now (the STR370 reference design diagram also shows that one 10KOhm
resistor should be changed for 12Kohm and the in line resistor should be 220Ohm so I can change those accordingly),
So let's suppose I'll do that, could I hurt things by doing this experiment?
If anyone has access to the schematics of this chassis or maybe even this set specifically, that would be very useful as I could then
know what the real values of the components are and what the B+ has to be.
Anyway I do appreciate the help and advises so far, and sorry for the lengthy posts!
(just trying to cram as much info as possible, heh).
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