Scored an Admiral 19A11

[Crist Rigott]

Guys, I've got another problem! Some background first.
all through this recap and recarb, when I powered up the TV, the picture seemed weak. I had to twiddle the Contrast, Brightness, V. Hold, and H. Hold controls just right to get a picture. The picture was always a bit unstable. It would flicker and when I adjusted the Contrast control, the V. Hold would need readjusting. Though I think this might be a nature of the beast. As I went through the recap, the picture got just a little bit better. Then when I was finished with all the recapping, the picture was still a bit unstable but the flickering all but stopped.
Then I changed the 8 resistors in the tuner. Now here's my problem. I have very good audio but no video. I have a raster but no video. No amount of twiddling the controls will produce a picture. I even tried another CRT with the same results. I replaced the 6AU6 Video Amp tube and even changed 6AL5 Video Detector tube and still no joy. I checked the 2 coils (Sams L14 and L15) or ( Riders, Wallace, and Admiral L9 and L10) and they checked good for continuity.
Could this problem be caused by something in the tuner? I figured that with good audio, the tuner was doing its job.
Any ideas as to where to look?
In the meantime, I'll hook video directly to the Video Amp and see what I get.
Thanks for your help.

Here's a link to the Wallace schematic. Thanks to Phil Nelson.

https://www.dropbox.com/s/vtr06fdq1z...opped.jpg?dl=0

[Crist Rigott]

OK, when I hook the video directly to the Video Amp tube, I get decent video.
Then I went back to the original set up and now I'm getting a very faint picture.

I'm thinking that maybe I need to just do the IF/Video alignment.

Can a problem with the tuner cause this problem? Just wondering.

[old_coot88]

Please don't mess with video alignment without first checking for plate and screen voltage on the IF tubes, and that their heaters are lit.

The set uses intercarrier sound. So you'd think that with a dead video IF stage, it'd kill the sound too. But since the sound carrier is FM, it could be going through by capacitive coupling.

[Crist Rigott]

Originally Posted by old_coot88

Please don't mess with video alignment without first checking for plate and screen voltage on the IF tubes, and that their heaters are lit.

The set uses intercarrier sound. So you'd think that with a dead video IF stage, it'd kill the sound too. But since the sound carrier is FM, it could be going through by capacitive coupling.

Fair enough. I'll check those voltages.

[Crist Rigott]

OK, here's what I measured. There was no signal to the antenna terminals.

Also the "mains" was only at 114VAC. Hence the low voltage on the heaters and B+ was only 237V. When the mains was brought up to house voltage of 124VAC, the heaters went up to 6vac and B+ went to 257V.

[jr_tech]

Got to get some plate voltage to pin 2 of the 6J6 for openers...perhaps the 15 k resistor in A4 is open?

jr

[Crist Rigott]

Originally Posted by jr_tech

Got to get some plate voltage to pin 2 of the 6J6 for openers...perhaps the 15 k resistor in A4 is open?

jr

Yeah, I agree. I checked that resistor. It ohmed out to 21K. I'll pull A4 and replace that resistor too.

I went through the tuner last night in great detail. No problems found except that resistor.
I have another tuner and I'll clip lead the tuner in and try it then swap tuners and try it again.
Then go on to an alignment.