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  #1  
Old 10-22-2017, 09:22 PM
Crist Rigott Crist Rigott is offline
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Zenith H2447R 19" Porthole TV

I just got this this weekend.






I tested the 19AP4 CRT and after cooking it awhile and doing a Clean on it using my BK 467 CRT tester, the CRT did come to life but just in the green. This picture shows the condition with 6.3V filament.



This picture shows the filament at 7V.



Do you think I need another CRT? Let me know.
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Old 10-22-2017, 09:27 PM
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benman94 benman94 is offline
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Recap the chassis and do a normal restoration. The jug will more than likely produce an image, just not a super bright one.

I've seen dead looking B/W CRTs produce a nice, focused, fairly bright picture. The best CRT tester is a working chassis.

If you do need a CRT, a 19AP4 isn't terribly hard to find.
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Old 10-22-2017, 10:29 PM
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Quote:
Originally Posted by benman94 View Post
Recap the chassis and do a normal restoration. The jug will more than likely produce an image, just not a super bright one.

I've seen dead looking B/W CRTs produce a nice, focused, fairly bright picture. The best CRT tester is a working chassis.

If you do need a CRT, a 19AP4 isn't terribly hard to find.
I agree, the CRT will likely produce an acceptable picture. If need be, you can put a brightener on it. I put one on my "soft" CRT in my 630TS and it looks excellent.
That's a classic vintage TV by the way. Nice score! I've loved that model ever since a kid seeing it in the Stooges "Census Takers" episode.
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Old 10-22-2017, 11:40 PM
EdKozk2 EdKozk2 is offline
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Nice find Christ, and to have a working 19AP4.
Ed
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Old 10-23-2017, 10:06 AM
Crist Rigott Crist Rigott is offline
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Thanks guys for the comments. I'm very happy I got it. The cabinet is in very nice shape and the chassis is too. I'll do the restore and then see how the 19AP4 looks. I like the brightener idea too.
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Old 10-23-2017, 12:25 PM
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I've got a dual chassis 16" IIRC 24H20 porthole. CRT was stone dead and Nick and Mark hit it with a CR-70 rejuvinator and got it up in to the mid to upper red, set is all original caps except for 4-5 papers that were swapped for maroon drops in the 60's or 70's...It somehow came to life with a reasonably bright picture in that state.

Aside form the weak flyback on some portholes these sets are indestructible.
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Old 10-23-2017, 03:49 PM
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These things ABSOLUTELY Blow the minds of yr typical smart alec teenager...Its almost worth the money for what one costs just to see the reactions they cause...
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Old 10-23-2017, 05:35 PM
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Another thing to keep in mind: sometimes these tubes were last used 60+ years ago and have developed a very minor, and expected, case of cathode poisoning. The typical current draw of a tester is usually insufficient to bring the tube back up. Either forcing the tube to wake up via elevated heater voltage, cleaning it by pulling more current from the cathode a la the Beltron, running the tube on a working chassis with HV to clean up the cathode or some combination of the three is necessary to really get a tube working again.

My own two "dead" CRT stories: I won a 16AP4 at the ETF auction a few years ago that has been tested by some guy with a CR-7000. He wrote it off as a lost cause; it had low emissions and bad cutoff.

I won it for $5 or $10, cleaned it on the Beltron. Now it tests like a brand new tube, has excellent cutoff, and is residing in a nice little Emerson producing a flawless image.

The big Westy you just delivered for me looked poor on Beltron initially. Knowing I'd never find another 24AP4, I decided to bring the set up on a Variac. The tube is nice and bright, actually so bright it's irritating to look at.

I retested it on the Beltron after unplugging the set and going away for the weekend. This morning it read right at the top of the scale with a 30ish second life test. It just needed a good "scrubbing" of the cathode and just running the set for 4 minutes or so must have been sufficient to clear up the cathode.

Again, recap and run it. I think you likely have a good tube.
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Old 10-23-2017, 08:41 PM
Crist Rigott Crist Rigott is offline
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Thanks for the good comments guys. I noticed that my BK 467 tester needs calibration on the filament scale. When the tester reads 6.3V, the CRT is only getting like 5.7V under load. I didn't check the filament reading with no load.

So when I cooked it at "7V" it was really close to 6.3V and I still got into the green. I'm thinking now especially after everybody's comments, the CRT will provide good service.

Stay tuned for the restoration.
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  #10  
Old 10-23-2017, 10:34 PM
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Looking forward to watching this restore.
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  #11  
Old 10-24-2017, 06:50 AM
matt.caputo matt.caputo is offline
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Wow, must have been port hole Sunday. Lol. I also picked one of these up on Sunday as well. Same exact set. My 19AP4 tests strong, but the chassis will still need some restoration. Found this set outside Gettysburg PA.
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  #12  
Old 10-24-2017, 08:37 AM
Crist Rigott Crist Rigott is offline
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Quote:
Originally Posted by matt.caputo View Post
Wow, must have been port hole Sunday. Lol. I also picked one of these up on Sunday as well. Same exact set. My 19AP4 tests strong, but the chassis will still need some restoration. Found this set outside Gettysburg PA.
Yeah, very nice score. Glad your CRT tested so well. They are stunning TV's! Mine is in just as nice shape.
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Old 11-02-2017, 08:16 AM
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These things are just SO uncompromisingly W31rd looking... NOT in a bad way, heavens no...
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Old 11-02-2017, 03:39 PM
Crist Rigott Crist Rigott is offline
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These things are just SO uncompromisingly W31rd looking... NOT in a bad way, heavens no...
I have no idea what you just said.
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Old 11-02-2017, 11:21 PM
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Quote:
Originally Posted by Sandy G View Post
These things are just SO uncompromisingly W31rd looking... NOT in a bad way, heavens no...
l33t sp34k?! I haven't seen that for ages. w00t :3
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