Magnavox T931

[LukeSimon]

Thanks for the help.

I will measure B+, boosted B+, and ultor (aka high voltage cap) today and report back to this thread. I ordered newly made in 2022 Mallory capacitors so that I can keep the chassis looking as close to original as possible.



I have a theory about the no cataract. The TV has sliding doors that cover the screen, and this TV was a bedroom TV, not the main room TV. So it got light usage and was closed up and off for most of its existence.



Inside looks to be in good condition too. Definitely a secondary, back bedroom TV, and wasn’t the main TV of the house.

[zeno]

There was a cap, IIRC in the burst that killed the color
Boost usually feeds G-2 controls, audio & vert size. Looks
bright enuf so probably OK.
OK on HV probe, focus 5-6 KV apx & control near center of
range for best focus
Push & turn for VHF FT.
There is an auto color switch on the back. Best to leave it off.
It causes overall brownish color & was known as the "brownalater". Yuk !
Ticking, look inside the cage for arcing with room lights OFF.
Also do a complete clean up from HV rect to the CRT. It may also
be your focus problem.
BTW the pix looks about normal brightness. It will NOT be as bright as a newer Chromacolor jug or newer in line sets.

73 Zeno
LFOD !

[LukeSimon]

Originally Posted by zeno

Ticking, look inside the cage for arcing with room lights OFF.
Also do a complete clean up from HV rect to the CRT. It may also
be your focus problem.

Opening the HV cage unplugs the HV rectifier (red circled cover). How am I supposed to open the HV cage without unplugging the HV rectifier? Am I supposed to observe the arcing with the rectifier unplugged?

[Jeffhs]

Originally Posted by zeno

There was a cap, IIRC in the burst that killed the color
Boost usually feeds G-2 controls, audio & vert size. Looks
bright enuf so probably OK.
OK on HV probe, focus 5-6 KV apx & control near center of
range for best focus
Push & turn for VHF FT.
There is an auto color switch on the back. Best to leave it off.
It causes overall brownish color & was known as the "brownalater". Yuk !
Ticking, look inside the cage for arcing with room lights OFF.
Also do a complete clean up from HV rect to the CRT. It may also
be your focus problem.
BTW the pix looks about normal brightness. It will NOT be as bright as a newer Chromacolor jug or newer in line sets.

73 Zeno
LFOD !

You are so right about the so-called "brownalater" switch on these TVs, and also the "auto color" switch. These automatic color schemes actually did (and still do) more harm to the picture than good, so if you don't care for the effect on the picture (I never did), the best advice is to slide the switch to "off" and forget it. My Insignia flat screen TV has a menu adjustment which will switch the automatic color system on and off; I long ago turned it off and didn't look back. This TV has a picture many, many times better than any CRT television I have ever owned in my life (thanks to the DTV system now used world wide) and I would not dream of messing up that picture by activating the automatic color system.

BTW, as to "ticking" around the HV system, I would be absolutely certain all connections carrying HV are as clean as you can get them; this should eliminate the noise. I personally cannot see why an HDTV would produce this sound anyway, since I don't believe there are voltages anywhere near high enough (in the kilovolt range) in a flat screen TV which could arc to ground and cause interference in the picture, let alone make ticking sounds of any kind.