It seems that Zenith CCII's were made later than we thought

[radiotvnut]

I always thought the Zenith "K" line ('79) was the end of the line for the vertical chromacolor II chassis. Well, I was looking over my Sam's Photofact manuals tonight and found that, in Sams 1912-2 (6/80), there is a 23" Zenith single knob tuned console that uses the 23LC45 vertical CCII chassis. The "L" line tells me that it's from the 1980 model year and the photofact folder list 14 different models that this chassis was used in (all 23" screen sizes). I did a search of the online photofact index and it appears that the 23LC45 was the only CCII chassis offered for the '80 model year. I'm sure this "last gasp" CCII was simply an effort to offer an entry level console by using up the remaining CCII parts. Does anyone here have one of these "L" line CCII's in their collection?

[eberts]

That set was designed for the many customers who wanted a new TV that looked like their old TV.
There were thousands of "mature" consumers who didn't like the rectangular shape of the newer 25v rectangular tubes.
It had to look like their old Zenith or else they were not buying a new TV.
Zenith customers were a very loyal group then.
Those sets had excellant pictures, repairs usually consisted of some minor solder connections on the crt socket board, and replacing the 4 lead white capacitor.

[radiotvnut]

I do remember that Zenith was one of the last to make a 23" color TV. And, I've also seen 23" versions of this set that used the 9-160 chassis and 9-181 chassis. And, I think they were the last company to offer a large screen B&W set, discontinuing their 22" B&W line in '81.

[jg6364]

I have an old Zenith console model number L2316M chassis 23LC45. The bulb was not working in the tuner knob. when testing for voltage on the bulb, I accidentally touched an adjacent wire and now there is no picture or sound. Wouldn't you know that the bulb is now working. I checked both fuses and tried the circuit breaker but all checked good. There is power to the picture tube . You can see the neck of the tube light up when it is turned on. Any suggestions on where to start?

[radiotvnut]

Is there high voltage getting to the CRT? A quick check will be if you feel static on the screen as soon as you turn on the TV.

Assuming there is no HV, no lighting of the screen at all, and no kind of sound at all from the speaker; I'd check the power supply circuits. The CRT filament gets it's power from an AC winding off the secondary of the power transformer; so, that at least tells you that AC is getting to the power transformer. You really need to obtain a Sams Photofact service manual on this TV so that you can check voltages.

If you have HV to the CRT and/or lighting of the screen and/or any kind of noise out of the speaker; I would look at the tuner and the IF circuits.

[radiotvnut]

Does this look like your set?

http://www.videokarma.org/showthread.php?t=249183

[jg6364]

Yes, that's exactly like it.

[jg6364]

When I first turn on the tv, it makes the "crackling" sound and feel the static of the picture tube coming on. There is absolutely no sound and no picture at all but the back of the tube is doing the normal, humming and lighting up as if it is hot. It appears that the short happened on the terminal strip on back of the tuner control between the second and third terminal from the right . It was the terminal with the white wire with brown stripe and the terminal with the orange wire. The white and brown striped wire goes to two spots, one the tuner board and another on the 6 wire plug. The orange wire also goes to the 6 wire plug. I am going to trace those down and see if I can find an open or burned circuit.

[Gunslinger]

It's been a long long time. 130volt line ?? Open 10watt resistor?

[jstout66]

it's been a long time for me as well. IIRC High voltage and no picture was the video module, BUT I don't think that killed the sound.

[Geoff Bourquin]

I remember seeing a few occasions of low voltage regulator failure. It's the transistor just left of the AC cord interlock on the chassis. Could be the transistor or the zener on the back side of the chassis. IIRC that can kill sound and picture but HV stays alive. But it has been a long time for me too so my memory might be full of ....uh........oatmeal.

[jg6364]

That could be possible i traced back where the short occured, from the tuner control, and it goes to the back of the video module and straight to that transistor.

[jg6364]

Geoff, you were right. The transistor tested bad. I traced back to a bad diode on the power supply module. It is the only 24 volt diode on the board the rest of 600 volt diodes. At least that is what the schematic lists it as. I would like to find another power supply module and replace the whole board. If that is not possible I will replace the diode on the boards. Is there any other suggestions? Any information would be appreciated.

[jg6364]

The set powers on now but there is still a problem. Something is causing flickering and snow Any suggestions on what to test to help locate this problem?



http://www.youtube.com/watch?v=tpMMQF7vRzI

[radiotvnut]

I still have the part that I was supposed to have sent to you. Please forgive me; but, things have been a mess over here. I have it boxed up and plan on taking it to the PO tomorrow.