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-   -   Question about Zenith Z1512j TV (http://www.videokarma.org/showthread.php?t=276901)

Ck100 10-02-2024 09:33 AM

Question about Zenith Z1512j TV
 
I have a zenith Z1512j tube 14" B&W TV. 145 watts- 117 V.A.C. It's very clean and complete. The tubes all seem to be in place. The cord is ok
My question is simply . does it make sense to plug it in or if I did that and burned something out is it going to create issues for someone doing a restoration. I'm curious to see if I could get at least static on the screen but since I'm more of a collector then a tech I don't want to wreck the tv.
I appreciate this site and would appreciate any opinions.

Alex KL-1 10-02-2024 09:42 AM

Welcome to VK!

Old sets have several parts prone to catastrophic failure. If set are correctly restored before, it will not present any risk for high parts damage, but is imperative to check at least the power supply electrolytics and horizontal sweep oscillator and output. For avoiding headaches. Other circuits generally not make destructive failures.

Is good to read sites from restorers, like the pages from Phil's Old Radios.

Ck100 10-02-2024 10:39 AM

Thanks
 
Thank you very much. That helps a lot

Chris K 10-03-2024 07:15 AM

The power should be brought up slowly using a Variac. There are capacitors, especially in the power supply, that need to "reform" if the TV has been sitting for a long time. There are numerous factors that need consideration in a gradual power-up and it would be pointless to cover all of them in a single post. My advice would be to search google, YouTube and this site for topics such as "dim bulb setup", "reforming capacitors", "series string sets", "isolation transformer/current limiting variac". One thing is for certain and that is you will need to purchase and/or build some used or new pieces of relatively inexpensive equipment.

Or you could just slam it with 125V AC and see what happens! Will be entertaining either way.

Good Luck!

Yamamaya42 10-03-2024 07:56 AM

Break the chain first! As this seems to be a series strung set heater wise, so you would want to pull one tube to keep them from heating if you want to reform caps.

Info here.
https://www.radiomuseum.org/r/zenith_z1512j_16z25.html

Alex KL-1 10-03-2024 12:05 PM

https://www.angelfire.com/electronic...store_cap.html

Some examples of methods for reforming capacitors.

kvflyer 10-04-2024 07:38 AM

I might add that using a capacitor checker to reform electrolytic capacitors is not the best idea. Many use the EICO 950/950B or Heathkit C-3. They were designed to be a checker, not a reformer. The EICO will easily destroy the voltage pot and also, those power transformers were not designed to carry a constant load.

I sold a 950B on the auction site and it was in perfect condition. I got a complaint from the buyer saying that the voltage pot was burned. He had alluded to reforming capacitors. I had a couple new pots so I bit the bullet and sent him one. 100Kꭥ 4-Watt. EXPENSIVE!!!

Ck100 10-04-2024 02:33 PM

Thank you.
 
Thank you all very much for all of these detailed answers. I'm studying all this material. I'm also finding some of the websites suggested are very helpful.
Chuck


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