Ok, here we go - with the B+ adjusted dead on 135V, I re- installed the power board. As soon as I plugged in the set, the relays clicked, and then nothing. Last post I told you all three tubes were lit, with faint raster. I unplugged the 8 pin socket that appears to come from the convergence board to the PB. Plugged set in and it powered up with 3 nice bright horizontal retrace lines - red, green, and blue (convergence drifted?) across center of screen. The lines were not real clean, but bright enough for normal raster I would suspect if the vertical was working. I didn't bother adjusting anything. Unplugged power cord, plugged this 8 pin socket back in and plugged set back in. Hit power button, relays clicked (saw green power light on front panel), then shut down. I did have the set powered up with this 8 pin connected once, and got a picture, although it was very dark and grainy. I couldn't reproduce this again, and didn't get a look at the proportion of the raster looking at the tubes. Now concerning the 8 pin socket and plug - the socket at the power board has the following id's for each pin - -25, gnd, +25, PD, HV para, P key, V ret, V in . Best I can see all these terminate on the convergence board. There is a 4 pin plug on the convergence board that have these 4 pins (-25, gnd, +25, PD). I got so focused on checking solder joints on the covergence board, I never checked the damn voltages at this plug before I left my buddy's house. I am suspecting the PS may be fine, and the problem may be on the convergence board (yeah I better check the -25, and +25 supply). I will do this next trip for sure. I hope this info clues you onto a probable cause here. Until then I will check discreet components on the convergence board since I brought this home with me, and find out what the two big IC's with massive heat sinks function are. Is one vertical IC, and other convergence? I've always seen 3 convergence IC"s in big screens, but again I haven't been doing this for very long. Thank you once again for your help.
I have researched and found info on the STK4277SL (pincusion). I don't know if it's bad, but don't know how to test except substitution. I don't have the friggin schematic (another problem), but since the
-25/+25 voltages from the power supply tie to this IC, and a malfunction of vertical may be causing the set to go into shut down, would it be feasable to try replacing the IC based off the info I have given? Thanks all for any suggestions.