a real challange?

[Yamamaya42]

this is just not making any sense...

IF the flyback was damaged/ had a shorted turn, would I not also get weak Horz sweep at the yolk as well as poor HV?

BUT...
https://imgur.com/YanCyvE
they are perfect...
https://imgur.com/30SwwKS
Cathode of Damper

https://imgur.com/QAX2DQS
input to horz yolk coils , pin 4 of damper, 100x probe


this is getting very strange
if there was a FBT problem, should i not see it in the sweep output?

[JohnCT]

Originally Posted by Yamamaya42

then this has quickly become a lost cause, and wasted time and effort, as the chances of finding a replacement a pretty much none, unless there some how a way to fix it, which i really doubt..

I'm a recent joiner to this forum, and only recently been bitten with the vintage TV obsession, but aren't 630s like the most common postwar TV ever made? Must be tons of used parts available, perhaps from someone here.

BTW, on another thread, I was chided (gently!) about not doing a full recap on an old Andrea TV before doing any other work on it. My rationale was that if it had a bad yoke, HV transformer, or CRT (metal cone), it would be a waste of time on a rare bird like the Andrea. Once I verified the hard parts were good, I scheduled it for a full recap.

But I don't think you have a dead end here with a 630 clone. Best of luck.

John

[bandersen]

Yes, I would expect sweep issues if the was a short in the windings. Does adjusting the drive control do anything ? Also don't assuming anything until you can try a different 6BG6.
It's not the most common post-war set, but a lot were made. Total TV production in 1946 was only something like 180,000. Replacement flyback should not be too hard to find though. I believe a Thordarson FLY-1 is what you'd want. It was used in many other brands and models too.

[Yamamaya42]

flyback removed...

https://imgur.com/VQodl6R
https://imgur.com/qw1tylZ

There are cracks in the " doughnut" but not too bad, right now I think there is nothing to loose in covering the windings with corona dope.

at this point I tend NOT TO believe what the meter is telling me, as when I had this apart, I took the chance to check the 2 resistors under the HV rect base, the 3.3 ohm to the heater is OK, but the 1m going to the CRT anode lead checked wide open, VERY BAD, even with it like that, I was getting 5kv at the CRT.
So...
I have a new 6BG6G coming, gonna try and dope the FBT as best as I can, replace the 1m, put it all back and see what happens.

[Kevin Kuehn]

Originally Posted by Yamamaya42

flyback removed...

https://imgur.com/VQodl6R
https://imgur.com/qw1tylZ

There are cracks in the " doughnut" but not too bad, right now I think there is nothing to loose in covering the windings with corona dope.

at this point I tend NOT TO believe what the meter is telling me, as when I had this apart, I took the chance to check the 2 resistors under the HV rect base, the 3.3 ohm to the heater is OK, but the 1m going to the CRT anode lead checked wide open, VERY BAD, even with it like that, I was getting 5kv at the CRT.
So...
I have a new 6BG6G coming, gonna try and dope the FBT as best as I can, replace the 1m, put it all back and see what happens.

If the 1 meg anode lead resistor is open(really good chance) they can still arc some voltage across the deteriorated carbon. Why not disconnect the anode lead from the CRT and see if your high voltage comes up, and if not also check on the fly end of that resistor? And NO those Fly 1 style transformers are not unobtainium.

[Yamamaya42]

1 meg resistor replaced.
flyback put back in.
https://imgur.com/NV9COl1

taken with no CRT hooked up.

YES, adjusting the drive control has slight effect on HV, by about 1.5 volt.
At this point, I'm not sure if I believe what the DVM told me or not, as the HV is now normal. and the sweep looked OK,I did look briefly for a "Fly 1 " but did not get any hits, if it is really bad I'd have to look harder, but I'm not sure where


EDIT--
just hooked up a CRT and the HV went up to 11kv.
i am really doubting the FBT is bad now...

[Kevin Kuehn]

Originally Posted by Yamamaya42

1 meg resistor replaced.
flyback put back in.
https://imgur.com/NV9COl1


EDIT--
just hooked up a CRT and the HV went up to 11kv.
i am really doubting the FBT is bad now...

Sounds like all is well. The dag coating acts as additional filtering, or if no door knob cap the only filtering.

[Yamamaya42]

The IF is obviously going to need work. :/
https://imgur.com/jT1W485
https://imgur.com/VIv1zqV

yes, I now know I have the yoke on backwards :O

https://imgur.com/nFmlP4w

https://imgur.com/oGGx7gd
but this is through the tuner

[Kevin Kuehn]

For starters don't go randomly tweaking all the IF's. I'm reviewing the alignment instructions from Sams. Do you have an rf signal generator that you can trust the frequency settings? And a high impedance DC voltmeter(I prefer a scope) to monitor the AGC voltage?

[Kevin Kuehn]

Following Sams, you basically want to adjust only A4 and A6 on the coil you replaced per directions below. If you don't have a reliable rf signal source I suggest substituting a test pattern on a DVD through a rf modulator into the tuner. Assuming everything else was close, I think you could get away with visually aligning A4, A6 for best picture. Since it's a replaced IF you don't have much to loose by only adjusting those two coils. If you do that make sure you have the tuner adjusted for best picture. Since the sound is split from the picture at the tuner, don't worry about best sound for the time being.

[Yamamaya42]

Originally Posted by Kevin Kuehn

For starters don't go randomly tweaking all the IF's. I'm reviewing the alignment instructions from Sams. Do you have an rf signal generator that you can trust the frequency settings? And a high impedance DC voltmeter(I prefer a scope) to monitor the AGC voltage?

all I have are DVMs, not sure if they count a high impedance, but for most settings, they are asking for highest / lowest DC point, so a o-scope set to DC would work as you mentioned,
I do not have a generator right now, but am looking at...
https://www.ebay.com/itm/Signal-Gene...ry!78665!US!-1

[Kevin Kuehn]

Yes most modern DVM's are high enough impedance, but for myself it's much easier to watch an analog needle or scope trace moving than numbers flying by. Some DVM's even have a analog graph.

Your call if you want to wait until you have appropriate alignment equipment. My gut feeling is you could get your first IF stage visually better, understanding that you keep track of your starting points and you don't mess with any other coils. Generally it's not advised to adjust anything without having the correct alignment tools, although over the years we've been proven wrong when complete newbies pull off almost miraculous visual alignments. If you be patient I'm sure someone wiser than I will provide alternate suggestions.

Oh, forgot to ask, did you ever get your sound working?

[Yamamaya42]

Originally Posted by Kevin Kuehn

Yes most modern DVM's are high enough impedance, but for myself it's much easier to watch an analog needle or scope trace moving than numbers flying by. Some DVM's even have a analog graph.

Your call if you want to wait until you have appropriate alignment equipment. My gut feeling is you could get your first IF stage visually better, understanding that you keep track of your starting points and you don't mess with any other coils. Generally it's not advised to adjust anything without having the correct alignment tools, although over the years we've been proven wrong when complete newbies pull off almost miraculous visual alignments. If you be patient I'm sure someone wiser than I will provide alternate suggestions.

Oh, forgot to ask, did you ever get your sound working?

Yes, sound works, but at this point, I have to choose to tune in for better sound or picture
https://imgur.com/ej7sfiL
https://imgur.com/gbsSKCO
https://imgur.com/1oDkIJe
how it looks with yolk NOT backwards..

the problem is with trying to do the 1st IF visual is, there is on adjustment that you can get to from top and the other only from the bottom...

but in order to hook up the CRT safely I need to lay the chassis down, cutting off access to the adjustments on the bottom...
https://imgur.com/lsyrjzp

I have no easy way to have the chassis on the side and have the CRT supported, mainly cause of the short leads to the yolk

[Kevin Kuehn]

From those pictures it's difficult for me to tell just how bad the video really is. Any chance you have a test pattern DVD?

I understand the struggle of getting to both the top and bottom adjustments. I've been known to roll the whole shebang onto it's side, but only if there's a band holding the CRT secure.

Just for fun here's a couple pictures of me having used my HP8662A synthesized sweeper to align an Admiral 20Z1 chassis. The 8662 has 5 programmable markers and they are being intensity modulated using the Y axis input to the Tek scope. I know it's crazy overkill, but sometimes you need to do absurd things just because you can.

[Yamamaya42]

Originally Posted by Kevin Kuehn

From those pictures it's difficult for me to tell just how bad the video really is. Any chance you have a test pattern DVD?

I understand the struggle of getting to both the top and bottom adjustments. I've been known to roll the whole shebang onto it's side, but only if there's a band holding the CRT secure.

Just for fun here's a couple pictures of me having used my HP8662A synthesized sweeper to align an Admiral 20Z1 chassis. The 8662 has 5 programmable markers and they are being intensity modulated using the Y axis input to the Tek scope. I know it's crazy overkill, but sometimes you need to do absurd things just because you can.

i have the "Digital Video Essentials DVD" which has patterns on it, but Its not very user friendly, hard to get around on it TO everything and get to what you want.

building something to hold this little CRT with the chassis sideways is not impossible, just not very easy, no mounting points on it :/

I could try gluing something to it.. who knows.