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Old 12-27-2017, 01:47 PM
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1965 RCA 19" b/w KCS149 with remote

This TV is finally, finally working. I had to move my operation onto the kitchen table to get away from the cold in the garage.

The problem with the picture overloading was twofold. The wire that connects the boost voltage to the 1st anode of the CRT had come loose. The picture was going totally black when it was receiving any signal at all. But even after I fixed that, I still had the problem that depending on where I put the fine tuning I either had a snowy picture or overloaded picture, and the AGC control was completely ineffective even though the AGC circuit seemed to be operating ok. I had checked every component in the AGC circuit over and over again, tried substituting several 6AK8s in, and even checked with the scope to see what those horizontal pulses going into the plate of the ACG tube looked like. And none of that did any good. It turned out to be the resistor circled in the schematic. I would up changing the two next to it too (which were up by about 20% in value), but that one 68K was way up over 400K.

The picture of the set working was taken with no antenna attached and transmitting from down in the opposite side of the basement. I'll talk about the remote stuff in the next post...
Attached Images
File Type: jpg 65rca4.jpg (29.5 KB, 47 views)
File Type: jpg 65rca3.jpg (57.9 KB, 40 views)
File Type: jpg 65rca2.jpg (56.1 KB, 26 views)
File Type: jpg 65rca1.jpg (27.6 KB, 37 views)
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Last edited by Adam; 12-27-2017 at 04:28 PM.
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Old 12-27-2017, 02:04 PM
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I recapped the electrolytics in the remote chassis, and realigned it. The alignment for the channel turning function really had to be spot-on before it worked. And I had to clean some hard grease out of the mechanism for rotating the tuner.

I finally had a chance to use my RCA "Remote Control Standard SC-601" It basically produces a sine wave at all the different frequencies the RCA remotes operated at. It also has a built in microphone for testing remotes. You can just hook it up it the receiver instead of the microphone. I didn't have any guide as to where to put the scope, put I attached it where you see the arrows in the schematic. That was an easy place to attach the probe, right on the transistors on top of the board. Then you adjust the tuned coil corresponding to the frequency your using to maximize the amplitude of the wave on the scope. That initial transformer which all 3 frequencies pass through can be adjusted with any of the frequencies and the scope at any of 3 corresponding points. I tried it with each frequency separately, and I wound up setting it at nearly the same spot either way.
Attached Images
File Type: jpg rca remote2.jpg (12.3 KB, 24 views)
File Type: jpg rca remote.jpg (83.3 KB, 18 views)
File Type: jpg rcaremote3.jpg (23.6 KB, 25 views)
File Type: jpg rcaremote4.jpg (40.1 KB, 30 views)
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Old 12-27-2017, 05:41 PM
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Here it is all back together. I still need the correct brightness knob, and the CRT, while good, has some minor scratches in the face, so I'll be on the lookout for another 19DQP4. All 5 of my RCA rectangular b/w sets are in that 2nd pic - 1959 17", '61 19" with the remote, '62 19", '63 19", and this '65.
Attached Images
File Type: jpg 65RCA.jpg (34.3 KB, 45 views)
File Type: jpg RCS.jpg (31.6 KB, 52 views)
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Old 01-04-2018, 11:00 AM
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I have that knob, lots of them. Remind me when you're here.
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