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

[Electronic M]

Originally Posted by Kevin Kuehn

So you've completely lost high voltage, as in no more sparky?

Easy enough to change that resistor, I suppose?

If the resistor don't return the HV then check for arc at top of the 1B3 and if not there check voltages at the socket of the H output tube.

[vortalexfan]

Originally Posted by Kevin Kuehn

So you've completely lost high voltage, as in no more sparky?

Easy enough to change that resistor, I suppose?

Well actually I managed to get the High Voltage back, and all I did was swap out the horizontal output tube back to the original Meck branded one that was in there when I got it. But the picture still can't go very bright without having vertical retrace lines on it or the screen completely disappearing when the brightness is turned all the way up.

[vortalexfan]

Originally Posted by Electronic M

If the resistor don't return the HV then check for arc at top of the 1B3 and if not there check voltages at the socket of the H output tube.

The 1B3 still arcs at the top, so I'm suspecting it's definitely that resistor inline with the High Voltage anode for the picture tube.

[Kevin Kuehn]

Originally Posted by vortalexfan

Well actually I managed to get the High Voltage back, and all I did was swap out the horizontal output tube back to the original Meck branded one that was in there when I got it. But the picture still can't go very bright without having vertical retrace lines on it or the screen completely disappearing when the brightness is turned all the way up.

Weird. I thought you'd solved that high voltage fading problem a couple pages back. The retrace lines are probably because you have the brightness cranked to full to compensate for low high voltage. If I were in your boots right now(actually a long long time ago)I'd replace that 1 meg 1watt series resistor just for peace of mind. Then go from there.

[Kevin Kuehn]

Found it back on post 315 where you solved that high voltage sage by replacing the HV rectifier tube. Had a nice and bright raster.

[vortalexfan]

Originally Posted by Kevin Kuehn

Weird. I thought you'd solved that high voltage fading problem a couple pages back. The retrace lines are probably because you have the brightness cranked to full to compensate for low high voltage. If I were in your boots right now(actually a long long time ago)I'd replace that 1 meg 1watt series resistor just for peace of mind. Then go from there.

I'm working on it, one of the members here is sending me a new resistor as well as the knobs I need for this set as well as some tubes.

[Kevin Kuehn]

Excellent.

[vortalexfan]

Originally Posted by Kevin Kuehn

Excellent.

Yes, I think right now because of that resistor being bad I think its causing my High Voltage to be too low to produce a decent picture, hopefully once I replace that resistor I should have adequate High Voltage to create a good picture again.

[old_coot88]

I'm hopin' to be proven wrong, but there's no way that replacing that resistor is gonna restore HV to the CRT anode.

[vortalexfan]

Originally Posted by old_coot88

I'm hopin' to be proven wrong, but there's no way that replacing that resistor is gonna restore HV to the CRT anode.

Do you think maybe I should look into a brand new 1B3 tube?

[jr_tech]

Originally Posted by jr_tech

There is also a possibility that the sagging/blooming high voltage slump is caused by downstream problems such as a weak horizontal output or damper tube, or perhaps the horizontal frequency being way off. In such a situation, a good strong 1B3 might worsen the symptoms, while a weak one might act as a current limiter.

I would not pitch any 1B3s biased on performance in this semi-working set.

jr

Since replacing the horizontal output tube restored HV in this recent problem, I still think that is an area of concern.

jr

[Kevin Kuehn]

Originally Posted by jr_tech

Since replacing the horizontal output tube restored HV in this recent problem, I still think that is an area of concern.

jr

The horizontal frequency could be right on the edge of not wanting to resonant. Pretty common to be a little off after a full recap.

[vortalexfan]

Originally Posted by jr_tech

Since replacing the horizontal output tube restored HV in this recent problem, I still think that is an area of concern.

jr

Well the horizontal output tube that's in the TV now that brought back the High Voltage is the Original Meck Branded 6BG6G tube and the one that I had in there when I lost my high voltage was a NOS Tung-Sol 6BG6GA tube.

The horizontal Oscillator Tube which is a 6SN7GT which is an older RCA Replacement from the late 1950s that tests near the bottom of the good zone of my Tube Tester may also be causing problems as well, which I have a NOS Tung-Sol 6SN7GTB tube but the middle keyway pin is busted on it so I don't know if I can install it correctly for it to work in my set.

As for the horizontal frequency it's about as centered as it's going to get.

[old_coot88]

Originally Posted by vortalexfan

Actually the resistor was mounted on the top of the 5kV Doorknob capacitor and it measured 50 ohms shy of 1 Meg Ohm, so it drifted down a little bit over the years but its still within tolerance suprisingly enough.

which means that it could be the 5kV doorknob capacitor we'll have to look at next...

Dang. How'd I miss this post earlier? (Thumps forehead)

Is it honestly labeled 5KV? It should be rated at least 20 KV.

Temporarily disconnect this cap and see if the HV comes up.

[vortalexfan]

Here's a picture of what the picture looks like now.

See picture below.