perhaps what you saw was a bad tube with a purple gassy glow, like seen here,

https://i.imgur.com/z7NnpHg.jpg

and not a normal healthy blue glow of a working tube?
:yes:

I just for giggles tested the audio output tube and it showed grid emission it’s a new tube and didn’t show this when I got it would this be caused from running hot because I’m still not sold on the fact that this tube is supposed to run hot. The volume control is 2 meg I tested it at 2.4 meg.

as mentioned. audio output tubes get HOT!

2 alike tubes.


https://frank.pocnet.net/sheets/049/6/6AQ5A.pdf 10w max gets up to 250c!
http://www.nj7p.org/Tubes/PDFs/Frank/127/6GK6.pdf 17w max no heat listed, but you can bet it also gets over 200c.

this is normal

Ok I’ll leave it alone just don’t get why it’s now showing grid emission

As others have pointed out, don't take what any tube tester tells you as gospel, it's just a guide.

http://www.tungsol.com/html/faqs3.html

Lol got it.

When I got tubes for the set I had got 2 6eh7 tubes GE and I usually test them and in testing them they were completely dead no reading at all. Just never know what you might get. Someone should come up with solid state versions of tubes or if it can be done at all.

This is what I got and it would flicker to almost a picture but this is it.

This is all I get

since video input was OK, this may be a Tuner or IF problem. :(

This picture was taken just before shutting down and pulling the 6hs8 tube

unfortunately if this IS an IF failure, there is no way to track it down unless you know someone who has a piece of equipment like a Sencore VG 91 Universal Video Generator, and can trace which area has the fault.

It also takes exp to use.

If it is the tuner, yo can try to use a sub tuner like.

https://tinyurl.com/2fabnfdu

i have one of them and they DO work!

since you have no alt way to feed in a tuner source. a start would be a new set of tuner tubes, if this has not been done already.

esp the mixer/osc

Sams shows 2 diff tuners so you will have to look for what you have.

That pic you posted looks like a very weak input signal that the TV can't lock on.

as stated above, this can be because of Tuner and/or IF section.

While it does look like a weak signal but it will flicker and get really clear and a picture will almost appear I was able to see a person but then it went back to the snowy image.

Possible AGC problem?

Has the new V6 (6HS8) been put in?
This is the point one would use a scope to look for the 450v signal on pin 3 of V6, and the others.

Is the AGC line at tuner plug .4v? (pin3)
Bad M1/C8/C18/C14?

What is the video source? ( macrovision problem? )
have you tried changing the rf modulator input from CH 3 to 4, and see if 4 is any better?
Sometimes there is just too much rf interference on CH 3, and trying another may help.

I didn’t get the 6hs8 tube yet and the sound at one point seemed better on channel 4 and I use cable and the same line is good on all my other tvs.

I believe I changed those 3 caps already but m1 is a fuse wire if that’s bad then no power to the set.

that should have been K1, the couplet for AGC, I saw it wrong, the schematic is a bit fuzzy. :/

Where did you see k1 I can’t find it.

http://suzaku.live-evil.org/k1.jpg

it can be located via page 6 on the SAMs, left side 1/2 way down,

Ok that’s the network that has several legs on it I believe.

If that’s bad I Doubt I could locate that part it looks like it could be made up it’s all resistors.

If bad, it would have to be made up on a small pcb, It's been done before.
https://retrovoltage.com/2014/10/09/...tric-circuits/

So this agc network would this be a cause for the voltage being pulled down via the 6hs8 tube ?

No, if not working the way it should, the AGC voltage/pulses would be all wrong, and tuning and IF would be all messed up and you would not be able to tune in anything.

Ok but when I get the tube I’ll try it but overall I still have the voltage dropping so if the tube don’t work out I’m still looking for a cause for the voltage dropping.

Timmy
Could you sum up what is wrong with the TV NOW without going
through the previous repairs.
In other words plug it in & see what happens like you never seen the set before.
I have lost track......

Prev screen shot looked good. But long distance troubleshooting is a challenge !
Many of us could take the TV like shown in the screen shot & vastly improve it
in seconds. That would maybe weed out problems.
Also remember NEVER trust a tube checker. The best checker is a known
good NOS brand name tube. We had an advantage here. I could turn
around & pull a tube from the shelf. It was abt 8' long & 5' high with sleeves of common tubes, more old numbers on shelves in the crapper.

73 Zeno:smoke:
LFOD !

ok first the pic with the face was to rule out the video amp and output by injecting video. Turn it on b+ good few seconds later b+ drops and in doing so the horizontal oscillator won’t run because b+ is being pulled down to far so in using the sets IF cannot get an image weather or not the voltage being draw down has to do with that I don’t know maybe there is an IF problem as well. I have a tube coming maybe this is the problem I don’t know until I get it to try.

Got the 6hs8 no different but I did pull the 6cg7 AGC and vertical multi voltage stayed up I got a new 6cg7 made no difference so the one vertical half is working because I have a full screen so that may leave it to an AGC problem still bearly any sound scratchy static sound and with the 6cg7 in I can here a buzzing from somewhere. If k3 is bad or the cap inside is shorted I can make it up but it shows a line under the 94k resistor which is the .002 cap but it also shows a ground in the center of the line so where does the ground come from. I don’t remember seeing a cap with 3 legs. Does this mean 2 caps one on each side of the 94k resistor both to ground.

Does anyone know what this T line means 2 .002 caps one on each end of the 94k resistor

That is another couplet, like K1. K3 is a combo part, 2 resistors 1 cap in 1 package.

But the T does it represent 2 caps one on each side of the 94k

It intends to show .002 distributed across the resistor. When making a replacement put a .001 to ground on each end of the resistor so the total is .002

Is there another resistor that is covered by the black splotch?

remove V1,V2,V3 ,V7,V8.

feed video back to test point B like you did before and see how long it can run like that.

No there is not only one for this area.

A more common interpretation of the separate component intent of that figure
is two resistors of half the listed value in series with the listed cap value attached between their center to ground. That of course assumes that the big black dot is meaningless.

You really need to get or borrow a scope to sort out messy problems like these.

and a better DVM. :yes:

Well I have more problems I plug it in to check video again and now I lost vertical deflection so this has to do with no video and recently sound was lost I originally pulled the 6cg7 and the voltage draw stopped pulling down so I put the tube back to check injecting video only to find vertical is gone and now the tube in and no voltage draw. So it’s like whatever was shorting now burned altogether and no more draw down. This set is really bizarre.

So now chassis has to come out and this time it’s not going back in until I find a problem or problems.

So I’ll cut the 2 couplets out and test them if bad then I make them.