73 Zenith Chromacolor II no picture

[Chad Hauris]

The filament voltage in this set for the crt should come from the power transformer, not the flyback...there may be another transformer to provide a smaller "instant on" filament voltage too.

Damage from a cracked CRT can be very subtle sometimes...It may not appear right after the damage is done but it can take a while for the CRT to air out. I have seen this in a dumpster-salvaged Zenith. The focus pin had been cracked off and I was able to solder a wire to the nub to get it going but there was a micro-crack that caused the CRT to go bad after several months.

[kc8adu]

Originally Posted by jonnic

The crt cap is orange. The tube worked fine in the guys shop. The picture was snowy and out of adjustment. It didnt start any this till I got it home and hooked it up. He said it hadnt been used in a while.

the crt cap is not the issue.
look at the horizontal output heatsink.under the bottom edge the will be a cap.
is it white or orange?
the sets with multiple smaller caps would still fail but lose just one and lose a bit of width.
iirc those were a 22-5001.
same thing white=replace
orange=ok

There is a white capacitor right below the horizontal output heatsink. I misunderstood about the cap. I would say the crt is shot so the set may as well go to the trash. Its a shame. Its a nice looking set. It seems strange that so many parts can go bad in a matter of seconds. I will save as many parts as I can. It has several good plug in modules.

[JCFitz]

Originally Posted by bobgary

Before you start tearing the set apart, see if you can find somebody with a CRT tester. It would only take a few quick checks to know if the CRT is now bad or not.

I would say a good idea.Barring that you can remove the yoke from the neck of the tube like I posted earlier to see if the capacitor did the nasty deed.(be sure and mark it's position)Most of time the neck will come right with it if it happened.You can clearly see the star point where it arced through and the rest of the way around will be as smooth as if someone took a glasscutter to it.Such a shame it never got the upgrade.A lot did but a lot of them didn't.

[3Guncolor]

Does the white cap below the heat sink have four wires or two? (Two on each end =four) The E sets had a small 2 lead cap below the heatsink. It was the F line sets that mostly had the 4 lead cap problem. I would hate to see a set hit the dumpster if the CRT is still ok.

[JCFitz]

Originally Posted by 3Guncolor

Does the white cap below the heat sink have four wires or two? (Two on each end =four) The E sets had a small 2 lead cap below the heatsink. It was the F line sets that mostly had the 4 lead cap problem. I would hate to see a set hit the dumpster if the CRT is still ok.

That's exactly what I would like to know.Hate to see it thrown away.Those sets had excellent pictures and long lived picture tubes.

The white cap is a 2 lead cap. I took the yoke off today. The clamp holding the yoke broke when I was removing it. I didnt notice any cracks in the crt. The neck stayed on too. It looked normal to me other than some dirt. Maybe I got lucky but no glowing in the neck doesnt look good. I will try to figure out a way to have the crt checked.

[3Guncolor]

There should never be any glowing in the neck of a good CRT. The only glowing would be at the very end of the CRT guns right behind the socket.

Does anyone here have a good used tripler for this tv. I also need the clamp for the yoke. What mfd and voltage is that white cap? I dont want to spend too much on this set.

[bgadow]

I would bet that the crt is perfectly good. I recall an RCA I had that with an intermittent arc in the neck caused by a bad video tube. I don't understand the how or why but it happened. Someone here is bound to have the tripler.

[kc8adu]

do the crt heaters light with the fly disconnected from the tripler?
you should see 3 spots of orange fire in the very rear of the gun assy.
if yes the tripler may have shorted internally and dumped 25kv onto the focus wire.
i have seen this a few times in the several hundred of these chassis that have crossed my bench.
this failure also burns up the spark gap in the crt socket.

The crt doesnt do anything with the tripler disconnected. It arcs blue with it connected. I think I will look around for someone with a crt tester and have it checked before I go any further with it.

[jstout66]

IIRC Couldn't the module for the video driver (the one that says HOT) cause this problem. I would bet the CRT is fine. The Zeniths I saw that had the "bad" caps usually blew the neck of the tube off. Also they usually made a big bang when they went......

[Chad Hauris]

You need to see if you have 6.3 volt filament voltage to the crt. What I have done is take a fairly big 6 volt filament tube like a 6JE6 and hook up the filament with micro clip leads to where the crt filament leads (brown leads) connect to the power transformer...see if the test tube glows. If it does you either have bad crt or bad connections in the crt socket.

There may be a dc bias voltage on the crt filament leads up to 150 volts in some sets, not sure if Zenith solid state has this but I would make connections with set unplugged and be aware of the possibility of this voltage at fil. leads.

[kc8adu]

Originally Posted by jonnic

The crt doesnt do anything with the tripler disconnected. It arcs blue with it connected. I think I will look around for someone with a crt tester and have it checked before I go any further with it.

where are you?