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#1
11-20-2012, 07:03 PM
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More about my new (old) 1954 Philco...
I adore the damn thing. I know I gotta fix it, but I think I'm a little bit afraid to touch it. What if it stinks up the whole house like a giant eternal sulphur fart? What if I electrocute myself, like 90% of the people I tell about my TV suggest I might do? My worst fear of all, I suppose, is that the PICTURE TUBE might be toast, and that there isn't a replacement to be had anywhere on Earth...
I do have quite a bit of experience in taking things that don't work and making them work again, but still, somehow, this Philco stands in front of me as a real challenge. I need to get going. Anyway, I made myself a hat, to psych myself up. The Repairman Cometh, right? 
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#2
11-20-2012, 07:11 PM
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If you don't have a picture tube tester, this article explains how to check the filament with an ohmmeter to tell if it's a dud.
http://www.antiqueradio.org/FirstStepsInRestoration.htm If the filament is intact, the tube may be dim, but it might be good enough to get you through the restoration, anyhow. If you have zero experience working on old tube devices (radios, whatnot), a TV is not the ideal beginner's project. Skimming a couple of B/W TV restoration articles in this section should give you an idea what's generally required to get them working: http://www.antiqueradio.org/restoration.htm Regards, Phil Nelson Phil's Old Radios http://antiqueradio.org/index.html
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#3
11-20-2012, 07:24 PM
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Thanks Phil, for these tips, I am going to check them out right now. I do have fairly deep experience with wiring diagrams, soldering, and using volt/ohm meters, so I guess I have a fair chance of firing this thing up. Uh, maybe fire isn't a good word to use here...
Going to read about the picture tube ohm testing, thanks again!
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#4
11-24-2012, 11:54 AM
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I am wondering, what should I do first before anything else, test the picture tube? I read up on checking the tube with an ohm meter, which I am going to do, but should I be in the market for a tube tester or a picture tube tester/restorer? I suppose if the picture tube ends up being no good, I am stuck before I even get started...
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#5
11-24-2012, 12:41 PM
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Check the picture tube filament with an ohmmeter first. As you say, if the tube's a dud, you may not want to invest a lot of money and time in the TV until you have located a replacement.
It's premature to buy a tube tester. Many vintage testers will need some repair, just like the vintage TV you're proposing to fix. You don't want to be one of those guys who ends up with a garage full of broken stuff and no idea where to go next. You can do the same filament test on the TV's small tubes. If they pass this basic dead-or-alive test, many of them (perhaps all of them) will work OK in the TV. You could also contact an area collector club and ask whether someone there has a tester that you can borrow. Or, perhaps you could bring your tubes there for testing. Here's a list of clubs: http://www.antiqueradio.com/clublist.html Phil Nelson
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#6
11-24-2012, 03:33 PM
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Gotcha on the testing tools... I wouldn't go crazy spending on the stuff anyway, but it makes sense that if a tester is as old as the TV it's testing, the results would be suspect at least. The Philco model number of the TV is 22B4110 and I have the SAMS diagrams on a PDF but, so far I haven't located a diagram of the picture tube pin-outs for testing. I am going to try the website links from your earlier post for help with the picture tube, thanks!
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#8
11-24-2012, 04:39 PM
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Judging from your earlier post in the other thread:
http://videokarma.org/showpost.php?p...8&postcount=15 Quote:
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#9
11-24-2012, 05:25 PM
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Quote:
I just tested the heater circuit terminals 1 & 12, and the resistance was a firm 1.3 - 1.5 ohms. That is a good confirmation yes? 
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#10
11-24-2012, 05:33 PM
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Dumb Question #1: On the hi-voltage wire, the one that connects from the evil looking cage to the picture tube off to the right side, there is no round boot, or seal, pressing against the glass of the picture tube to prevent leakage/arcing. It's just the wire, clipped into the hole. I have never seen a TV without a seal present at this location, it must be missing? It's hard to tell if anything was ever there in the first place. Everybody's advice so far has been spot on, thank you all very much for taking the time!
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#11
11-24-2012, 06:04 PM
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Quote:
Yep. The fact that it lit up when powered on is an even better one, and proves that the tube is still under vacuum, which a simple resistance test will not. Plugging the set in straight away still wasn't the greatest thing to do, though. Neither indication proves that the picture tube is good, as only putting an image on the screen will do that. But you are off to a great start. Get yourself the Sams folder covering that set, and start compiling a list of capacitors for replacement. All the electrolytics and paper/film caps should be replaced right off the bat. Look around for any obviously burned or damaged resistors or other components at the same time. If you can get access to a tube tester, pull all the tubes and check them, replacing any that are obviously NG (open filaments or shorted). Any that show very low emission should be changed, as well. Give everything a good cleaning and inspection while you are waiting for the new caps to arrive... The unbooted HV connection is standard Philco practice. Nothing missing, it was likely never installed. Last edited by N2IXK; 11-24-2012 at 06:09 PM.
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#12
11-24-2012, 06:06 PM
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I have two 1953 17" Philcos that do not have a HV boot, so I think that is normal for these early Philcos. What is your CRT type? Early tubes such as the 21EP4 ran at only 12 kV ... later aluminized version (21EP4B) ran at 16 kV.
jr Last edited by jr_tech; 11-24-2012 at 06:14 PM. Reason: Add HV data
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#13
11-24-2012, 07:35 PM
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Is that a split chassis job? If it's a 1954 model, it probably has a 21ZP4 CRT.
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#14
11-24-2012, 08:32 PM
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Great stuff, I am really getting a good feeling about this television's chances to once again broadcast all the exploits of the Robinson family, the Robot, and Dr. Smith...
I do have the SAMS folder for this model, and I believe I am up to the chore of changing out the capacitors. I hope it will not run into hundreds of dollars though. The picture tube is type 21ZP4A, and yes it is a split chassis. It sure looks like scrubbing all the dust off of the interior chassis and other components is going to be an arduous task. But nothing in there so far looks burnt, or overly corroded that I have seen. It's great to know that the set is is NOT missing a hi-voltage bootie! I have not yet removed the two main chassis from the television, but I guess that will be next. Again, I really appreciate all the good advice I have already received. Raddion
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#15
11-24-2012, 08:38 PM
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Quote:
__________________
 Looking for zenith cobramatic parts -johnny the raster master!
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