Old Muntz TV for sale Locally to me, Should I pick it up?

[Electronic M]

Originally Posted by vortalexfan

Yes, I did find that manual and downloaded it, and read through it, just not sure where where everything hooks up in regards to trying to find the waveform for the horizontal and vertical oscillator and what switches should be used and which ones shouldn't be used.

Sam's lists scope measurement points and shows correct waveforms in most TV manuals.

[Kevin Kuehn]

Originally Posted by vortalexfan

Yes, I did find that manual and downloaded it, and read through it, just not sure where where everything hooks up in regards to trying to find the waveform for the horizontal and vertical oscillator and what switches should be used and which ones shouldn't be used.

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.

[Kevin Kuehn]

Originally Posted by Electronic M

Sam's lists scope measurement points and shows correct waveforms in most TV manuals.

I've never seen much until you get into the late 50's -60's. Riders is more likely to show whatever the manufactures provided. But it's still best practice to do some reading and get yourself a basic understanding of where to look, and how to use an oscilloscope. I suppose some of the old time repair guys will say you don't need a scope, but that's a hard way to learn in my opinion, and without the theory you end up learning from trial and error more so than understanding what's actually going on. Maybe that's just me, because I tend to grab the scope even when taking DC voltage measurements, just to see how much and what kind of AC signal may be present.

[vortalexfan]

Originally Posted by Kevin Kuehn

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.

[Kevin Kuehn]

Originally Posted by vortalexfan

OK, so I figured out the mystery of the model number of this set and the one like mine that was in another thread on here.

Sam's DID actually cover this set, in Set 173 Folder 10, the actual model of this set is the Philharmonic Model 820! The exta zero was a typo on the model no. sticker and if you look carefully at the model number sticker the extra zero is actually crossed out, with a felt tipped marker.

So what this TV is actually is a Philharmonic Model 820 TV that was made by Meck Industries of Plymouth, Indiana.

I don't have Sams set 173 but I looked up Philharmonic 820 in my Riders index and it's in Riders 11. I looked at that and I'm afraid it's not the same as your TV. Completely different circuitry with a rectangle CRT. Doesn't your TV look exactly like the one pictured on the front of Sams Set 101 folder 5?

[Kevin Kuehn]

Originally Posted by vortalexfan

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.

[vortalexfan]

Originally Posted by Kevin Kuehn

I don't have Sams set 173 but I looked up Philharmonic 820 in my Riders index and it's in Riders 11. I looked at that and I'm afraid it's not the same as your TV. Completely different circuitry with a rectangle CRT. Doesn't your TV look exactly like the one pictured on the front of Sams Set 101 folder 5?

Yes, once I looked up the Philharmonic 820 I realized that it wasn't the same set as mine, but I wonder why the second zero on the 8200 was crossed out on my TV's Model number tag then...

Also its quite strange why Sam's never covered the Philharmonic 8200, but covered its sister unit the Meck, although I guess if they are technically the same unit it probably wouldn't of made sense to cover both units when one would of sufficed to cover the other.

[vortalexfan]

Originally Posted by Kevin Kuehn

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...

[vortalexfan]

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?

[vortalexfan]

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.

[Kevin Kuehn]

Originally Posted by vortalexfan

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?

[vortalexfan]

Originally Posted by Kevin Kuehn

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.

[Kevin Kuehn]

OK, I'll be looking forward to those voltage measurements. My next question is do you have a high voltage probe? If not a probe how about a compact florescent bulb? You need something to indicate the presence of high voltage. Once you know you have HV, my next concern would be adjusting the ion trap. The ion trap has to be set properly or you'll never see a raster.

[vortalexfan]

Originally Posted by Kevin Kuehn

OK, I'll be looking forward to those voltage measurements. My next question is do you have a high voltage probe? If not a probe how about a compact florescent bulb? You need something to indicate the presence of high voltage. Once you know you have HV, my next concern would be adjusting the ion trap. The ion trap has to be set properly or you'll never see a raster.

Ok, so pin 3 of the 6V6 tube is giving a funky reading, it's giving a reading of -0.195vdc which doesn't seem right...
And that reading was taken in reference to pin 8 of the 6V6 tube just like the manual said.

And no, I don't have a high voltage probe.
I do have some CFLs but they're all burned out or broken unfortunately.

[Kevin Kuehn]

What did pin 4 measure? If you have dc voltage on pin 4(screen) and nothing on 3(plate)I'd suspect the primary of your output transformer could be shorting to ground. You could also try measuring those two pins in respect to chassis ground. Any voltage readings on those two pins will indicate if there's a short in that transformer primary.