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I couldn't leave the set alone. Bottom line, IT LIVES!
The CRT is strong, bright and sharp.
I started out by getting the horizontal oscillator going. After recapping the horizontal circuits, I pulled the horizontal output, and fired up. No horizontal drive. I traced that to an open oscillator coil. Lucky for me, the open was about 2 turns in from the outside end of the coil, so I was able to unwind a few turns and reconnect the wire to the lug. I was rewarded with about 70-80 volts p-p of clean horizontal drive. The loss of the vertical oscillator was the cumulative effect of several bad capacitors and a 1 meg resistor that was a whole bunch more than a meg. Also, the size and linearity pots are real touchy.
Now lets see if the tube lights up.....It does! I even have static, and I have not even changed the caps in the audio video and IF circuits yet. I supplied a ch 3 signal, and saw a pale picture with no sync. By this time I'm feeling very hopeful. I threw some more caps at it and the contrast became great, and I have enough sync to lock the horizontal, and loosely lock the vertical. Sound is good except when computer graphics show on the screen, then it buzzes.
I still need to restuff the electrolytic cans. For now I have a few modern caps tacked to the bottom of the old caps.
I need to find my box of rectifier tubes. I'm using a pair of 1N4007s in place of the broken 5U4 and a 100 watt bulb in series with the B+ to simulate the drop in the tube.
I checked the Sams for the model 2297 and discovered it is not the same as my set, but most of the circuits are close enough to guide me. Again, thanks for that model number.
I still need to deal with the height/lin pots. The right spot seems especially touchy, so the picture is a little out of shape.
That's all for now.
Last edited by Geoff Bourquin; 07-15-2015 at 10:20 AM.
Reason: Added picture
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