Westinghouse TV no picture : Strip or fix?

[JesusJones]

OK I AM thoroughly CONFUSED. LIke a monkey in space.
I was looking over the the wiring of this tv. And it isn't an exact match to the schem. OR this TV is wired up very wrong. I just don't know.


According to the schematic the damper tubes pin 5 should be hooked up to the power supply.(Point 1 for 60hz operation) Instead in the TV pin 5 is directly connected to pin 1 of the horiz output tube.

PIn 6 of the damper tube is also directly connected to the 60hz line right from the wall. It then goes (via 25 ohm sand resistor) to pins 7 and 6 of the horiz output tube.

And pin 3 of the damper goes to Lead 5 of the HV rect flyback transformer thing.(In the box) Pin 8 of the damper goes to 3cb6. And pin 7 of the damper goes right to pin 2 of the horiz output.

What confuses me here is that the horiz output should be connected to the high voltage Through a 8 k resistor then an adjustable one (Those resistors are there) But it goes from pin 5 of the damper instead of the Power supply Or 256 volt line.
And pin 5 of the damper should be hooked up to point 1 on the power supply(Which it isn't)
I AM STUMPED. STUMPED I TELL YOU

If you would like I will take detailed pictures then edit them on paint to show you what I mean. And point things out

P.S. The voltage on v15's plate should be 220v and it is much less than that. I am trying to give out as much info as I can here

P.P.S. No it is wired right I am just stupid. THe wire was hidden behind a large paer cap.The 256v goes to the 8 K resistor. Then it also goes up to the damper tube(pin 5)

[JesusJones]

UMMMMMMMM!!!!!!!!!!!!!!! I think theres picture folks


I turned it on.....My plan was to test for 256 volts. And just before I did I turned all the adjustment knobs to center. Turned it on and it started making some noises that scared me. And then flash! I turned it off so fast. You can't even measure that amount of time(Just kidding, but it was quick) This scared me. ALOT

But this flash. I do this think it was the screen. So I tried again and it flashed again. But by this time I was shaking so off it went again.

I THINK ITS WORKING!

[JesusJones]

OK so i tried it again this time with intent of leaving it on and nothing. No flash no nothing. Back to dead. This is bothering me


The width control. This resistor is not functioning properly I think.
With my ohm meter hooked up to it set on 2000k I can get it to read zero And i can get it to read Nothing its either zero up to 12k Then It says there is no connection.And this happens within 1/8 of a turn. After turning the TV off I actually got some picture to show up. I wouldn't call it picture though it was just light.

My question now is. Would this variable resistor screw the whole thing up. Cause it kinda seems like it did.(it is the width control one hooked up to horiz output tube.)

SO will it need cleaning or will I need a whole new one.And if I do need a new one, ElectroKing you will have to tell me what it is I cannot make it out from the schematic.
Thanx
Rudy

[electroking]

Hello again,

Sorry, I'm very busy with work today and tomorrow Friday, then I must go away
over the weekend. The fact that you got 'something' on the screen (even in a
transient fashion) means there was high voltage at some point. You're on the
right track as long as you are studying the schematic carefully and noting the
(hopefully small) differences with respect to actual circuit construction.

You can possibly clean the variable resistor with a proper cleaner fluid designed
for the purpose. If there is a hi-fi or electronics store in your area, they might
be able to provide the right stuff.

I will take the time to study your latest posts further when I get back on Sunday
night. Don't lose too much sleep, keep up the careful approach and you will
make progress. Bye for now!

P.S.: pin 1 of H. output tube is unconnected, it is just used as a tie point.

[JesusJones]

Alright well enjoy your weekend I will to. And I'll sleep

Yea I'll clean The pots out tomorrow Or something like that. More fiddling
And hopefully she comes to life. And it sounds like theres a really bad gas leak when I turn it on. And interesting is that the picture mainly flashes when I power it down. Or maybe I'm just not giving it long enough.

[nasadowsk]

Oh hell yeah the width control could kill the picture. It's controlling the voltage at the horz output tube's screen grid. Without a good voltage supply there, you won't get much sweep, and won't get high voltage. And it's a 1 watt pot because it's drawing good current. If the cap after it is leaky or shorted, you'd get issues too.

As a temporary check, get a 1 watter about 1/2 the value of the pot, and jump it in place. The schematic suggests about 150 volts there, but it could be a bit more or less - it's really not a critical value.

The blue cloud tube, I'm gonna bet was the vertical output tube (12B4), and that's 560 resistor burnt up because you've got a short in there or it's gassy, or here's bad things in veritcal land. Here's a better idea than waste the resistor or toast a transformer or coil: Leave it disconnected for now - you'll have a disabled vertical section, but that's ok. Just keep the brightness down so you don't burn a line on the CRT. Concentrate on the horizontal section - it needs to work right first to make vertical work too (the vertical get's a boost from the flyback!).

The horizontal will come up weakly, but once it gets boost built up, it'll 'kick in' rather quickly and you should have high voltage along with it. That's when things get interesting

[JesusJones]

Well I don't know the value of this pot as of yet. Maybe it says it on the back. But I cannot get it from the schematic.

And the Hv does work when this Variable resistor is set to have some resistance.(And I am observing the voltage this resistor is dropping with my voltmeter. To make sure its not the full 280v like it was before, it's usually 20-40 volts)

And another question is how gassy should this TV be sounding when the HV is working. Cause I am usually overcome with fear when I hear this tv fully power up. Sounds like a cap is about to blow up in my face...or something. But it's definatley a gas leak sound.

And heres the real kicker. The tv warms up makes gassy noises. But no picture shows up. So I get scared after about 10 seconds of listening to the gassy sounds and shut it off.

This is when the tube finally shows some life. A large sweeping square shows up.
I got one good look at it.
It was a large square that took up the whole screen at first. And then shrunk rather uniformley, in the shape of a square. And this gives me hope. Cause that would mean that the horiz and vert are working...correct?

BUT WHY does it only work when I turn it off? Could I just need to hook up the antenna or something like this? No signal to make picture?

First I will check all the pots see If I can get them working. If not I have some kicking around but I'm not sure how much current they can handle.
They are larger than the ones in there, but that could easily mean nothing.
And earlier today I changed all the caps near that area. Cause I obviously had no HV.

More news tomorrow and all the help is appreciated guys

[bgadow]

A slight terminology issue: "gassy" refers to there being gas inside a vacuum tube. (where there is supposed to be, well, vacuum!) So that vertical tube might be bad. They sometimes glow funny when that happens. Could also be caused by something like a bad cap in the circuit, which is almost guaranteed in a set this age.

The sound you hear like a gas leak is almost certainly arcing (corona) somewhere in the HV line. It will be somewhere between the flyback and the HV connection of the picture tube. Could just be poor insulation or something too close to ground. One way that can work to find it...and this could take some bravery! (don't worry, it won't reach out and grab you from a yard away!) You need to turn the tv on in a dark room and then look at the chassis while it is making that sound. You likely will see where the problem is-a constant blue spark is common. If you find it, turn the set off and try to figure it out from there. Good luck!

[JesusJones]

The pot for the width control. I've been staring at that schematic crosseyed and with glasses and from across the room. And I think it says 15k does it not?


As for the gassy tube I tested it and it tests ok and with no shorts. Does that mean it's alright...ish?

And your dark room idea sounds like a very good idea. I did start it up last night in the middle of the night. (I have been working on this TV outside, it had alot of weird dust) And I didn't notice any arcing but I wasn't exactly looking for it either. That will be done tonight.
And from what I can see the HV line comes out of the box then right back to the side of the picture tube. It doesnt seem to get very close to ground but I will insulate and move it further.(Would electrical tape help?) The hv line also looks like some one burnt it with a soldering iron. Like a dip in the insulation, I'm sure you know what I am talking about. AT this same point the wire is tied in a large granny knot. It is not tight but rather loose. I thought this might be because the cord was just a bit too long.

Any suggestions??

Rudy

[JesusJones]

Alright I have a 5k pot that looks like it can handle the current.
But I also have a 20k that is fairly small but looks like it might be able to hack it.(doesn't look cheap)
The 20k is 1.5 cm in diameter and 8mm wide. Anyone think it wouldn't burn up?

The 5k is 2.5 cm by 1.2 cm So I know it will handle it but its only 5 k. Not 15K(which is what I think it should be)


And I didn't post this message when I wrote it so the 5 k is already in there for testing purposes. But if some one thinks the 20 k one will work I will switch it.

We have horizontal folks. The tv with the new pot is showing a line that goes down the middle of the screen. Horizontally. The gassy sound has gone away. Maybe due to the new pot or electrical tape I wrapped around the HV line. And still when I turn it off it goes over the whole screen Then disapeers. I'm not sure if it is doing the square thing anymore though. It sorta seems like it But It's to bright outside to really tell. I HOPE TO GOD I DID NOT FRY SOMETHING.

Any one have a guess as to why the vertical would kick in just as you turn it off?

Also the 560 ohm resistor appears to no longer heat up. And checks in at 530 ohms. Amd from the resistor all the way to the vertical ouptut tube there is 1240 something ohms of resistance.

[wa2ise]

Like a monkey in space.

Reminds me of an old space sci-fi movie, where at the last minute, they substitute a crew of humans in place of apes on some space mission. But they didn't have time to modify the banana dispensers...

Anyway

If you can't find a good high wattage pot, you could just use fixed power resistors of the same value once you identify what the setting of the pot needs to be. You can also parallel higher value resistors to fine tune downwards the resistance. But don't hand poke around with a resistor in your fingers, the horiz circuits can "bite you in the ass...". Turn the set off and tack solder it in, to try it.

If you need to replace the very high voltage cable feeding the side of the CRT, you could obtain such from a junked computer CRT monitor. Those are even better in that they come with a rubber suction cup like cover, to protect you from the high voltage at the picture tube.

[JesusJones]

Junked computer monitors eh?


I went to look at it again before I went for a smoke to celebrate my good progress and it seems like the whole screen is being sweeped. It is still much to bright out to really tell but thats what it looked like to me!
Can't wait till dusk!


Roughly how long should it take for this tv to warm up?

[JesusJones]

The screen is on

But still showing no picture. And its not really fuzz either. More grey than anything. Does it need to have an antenna connected. Or something in order to get picture. Or do I have more work to do?

ALso I am pretty lucky after warm up voltage at the horiz output tube is 150 -158 as stated by the schematic. So hopefully that works till I figure this whole. No picture thing out.


Could this possibly be a problem with worn or dead tubes??


Woooaaah. Just did another test watching from the back The tube in the bottom right v15 turned blue. But then went back to being fine. Should I worry about this? and would a gassy tube still check in fine on a tester?

[nasadowsk]

I'd be looking to replace that vertical tube, frankly.

At this point, you'll want to replace ALL the paper/wax capacitors, and I bet you'll see a decent raster.

Take some time, clean that HV box and around the CRT on the back by the 'suction cup' for high voltage. Get those leakage paths out of there.

I'd be looking at CRT voltages at the socket, see if they match the normal ones for that tube type.

Getting a raster means you've got working sweep, working HV, and a good CRT. You should clean up the horizontal and vertical circuits - get the caps replaced, check the resistors out, make sure it's behaving right. Then get that IF section and tuner going. Don't touch ANY adjustments for the IF or tuner stages (beyond the 'fine tuning' available on the channel knob).

Get an isolation transformer, and look at getting a variac, too, maybe. Old TV sets have a way of finding you once you revive one

Antenna - the better, the better.

Sweep is what TVs are all about - get it working right first, and everything else falls into place.

[JesusJones]

I forgot all about the fine tuning, I'll try it out tomorrow.

And here's what the tv can do at this point. For everyone that doesn't wanna read 7 pages of this.

The tubes all warm up. V15 the vert. output tends to glow blue slightly then go away(It also does not get overly hot).
The audio output tube also arcs inside sometimes during warm up.
The audio works. I can get voices and commercials and what not.
The crt lights up and gives me a big'ol grey screen. Switching channels to a tuned one "will" change the way the screen acts. Sometimes getting darker or brighter.
There is no fuzz/snow like a normal TV. Just grey. With very slight static. No snow.

Also (this worries me) when it turned on originally the upper half of the screen was full of "grey" lets call it.(Light) The lower half was "half filled" with "grey" then there was a solid white line, Then black till the bottom. Adjusting the vert height got it to fill the screen. But my concern is that, the bottom deflection yoke(I don't know terminology too well) is burnt or something. Causing the bottom half to not fully spread downwards, wild the top half is already off the screen.
Is this making sense to some one? And is this even possible.

And I did check the voltages at the CRT. The brightness voltage was off. Should have been 130v but it only got up to 70. But this was when picture was not working. The tv's brightness can make it go white at this point. So I think it works.

One more question is what does vertical linearity do for the picture? It's an adjustment located at the back.

P.S. Schematic on page 4 and pictures tomorrow showing what I get