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  #1  
Old 11-05-2019, 07:13 PM
vortalexfan vortalexfan is offline
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Originally Posted by Kevin Kuehn View Post
You would do well to find yourself a couple books on early television servicing. A very good one is Television and FM Receiver Servicing by Milton Kiver, or any TV servicing books written by Milton Kiver in the early 50's are going to be very similar in content. What you want is material from or slightly after the period of the first consumer televisions. Those will tend to give you the most basic understanding, although they are all going to assume you have a basic understanding of AC and DC circuits and AM radio operation. TV repair is one of those subjects where it's very difficult to jump in feet first without first making your way though the ranks of simpler circuits. You absolutely need a solid understanding of those basic building blocks.
I have repaired successfully many radios and have a basic understanding of how those kinds of circuits work. So I'm surprised that this TV is kicking my butt as much as it is.

Although I don't think it helps any that this TV was in a house with no roof and no climate control for over 20 years. That might be part of why this TV is giving me such fits.
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Old 11-05-2019, 07:40 PM
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Kevin Kuehn Kevin Kuehn is offline
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Originally Posted by vortalexfan View Post

Although I don't think it helps any that this TV was in a house with no roof and no climate control for over 20 years. That might be part of why this TV is giving me such fits.
You're exactly right. It's not a simple recap and play, this one requires more advanced troubleshooting and a deeper understanding of the circuitry. It's very difficult for anyone here to give canned answers as to what may fix it without being able to troubleshoot the circuitry.
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Old 11-05-2019, 11:06 PM
vortalexfan vortalexfan is offline
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Originally Posted by Kevin Kuehn View Post
You're exactly right. It's not a simple recap and play, this one requires more advanced troubleshooting and a deeper understanding of the circuitry. It's very difficult for anyone here to give canned answers as to what may fix it without being able to troubleshoot the circuitry.
my guess is that besides the capacitors being bad in this thing (which all of the capacitors have all been replaced now), ALL the resistors are bad as well which will require all of the resistors to be replaced as well, in order to help fix the excessive current draw.

I have about 25% of the resistors replaced already, and I think I'm making some progress, not a whole lot of progress but some.

I think I have the oscilloscope figured out as far as how to use it, I just need to figure out where the test points are for the horizontal and vertical oscillators, and figure out which voltage scale to and time scale to use to test the vertical and horizontal oscillators in this tv, which unfortunately Sam's isn't very helpful in that regard...
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Old 11-06-2019, 12:09 AM
vortalexfan vortalexfan is offline
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OK, I just had another thought, How would one test the Vertical output transformer, Horizontal output transformer/flyback transformer, and the vertical block oscillator transformer to see if they aren't shorted or open?
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Old 11-06-2019, 12:56 AM
vortalexfan vortalexfan is offline
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OK So here's a YouTube Link to my Video showing what the TV is currently doing.

https://youtu.be/TfFZxX8DOQU

Hopefully this will work better, and won't require you to log into a Google Account.

P. S. You'll have to turn up the volume really loud to hear the audio.
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Old 11-06-2019, 10:51 AM
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Kevin Kuehn Kevin Kuehn is offline
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Originally Posted by vortalexfan View Post
OK So here's a YouTube Link to my Video showing what the TV is currently doing.

https://youtu.be/TfFZxX8DOQU

Hopefully this will work better, and won't require you to log into a Google Account.

P. S. You'll have to turn up the volume really loud to hear the audio.
I'm not sure what I'm suppose to be hearing in that video?

Say... what ever happened you measuring those voltages I asked about per Sams voltage chart on the pins of the 6V6 audio output tube? When I asked you a couple pages back, you said you hadn't yet, but were instead going to replace every resistor because they were all bad? Those voltage measurements in that stage could be crucial to figuring out why R62 is overheating and the cause of your excess current draw. That circuit derives it's supply directly from the focus control through R62 and the voltages developed are provided to the entire audio circuit. I'm getting the impression that you prefer avoiding any troubleshooting, but would rather replace every component in sight. Eventually you're going to run out of components to replace, and then what?

Last edited by Kevin Kuehn; 11-06-2019 at 10:58 AM.
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Old 11-06-2019, 10:57 AM
vortalexfan vortalexfan is offline
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Originally Posted by Kevin Kuehn View Post
I'm not sure what I'm suppose to be hearing in that video?

Say... what ever happened you measuring those voltages I asked about per Sams voltage chart on the pins of the 6V6 audio output tube? When I asked you a couple pages back, you said you hadn't yet, but were instead going to replace every resistor because they were all bad? Those voltage measurements in that stage could be very crucial to figuring out why R62 is overheating and the cause of your excess current draw. That circuit derives it's supply directly from the focus control through R62 and the voltages are provided to the entire audio circuit. I'm getting the impression that you prefer troubleshooting, but would rather replace every component in sight.
Well I'm hearing what sounds like vertical or horizontal oscillation going on, but I'm not sure if that's what I'm hearing or not, it's a kind of medium pitched rapid snapping noise, very similar to a taser going off.
I need confirmation as to whether or not that's the vertical, horizontal or high voltage running.

As for the voltages on the 6V6, I got side tracked, I have ADHD, so I get side tracked easily.
I'll get right to measuring those voltages.

Last edited by vortalexfan; 11-06-2019 at 11:03 AM.
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