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#1
06-02-2020, 08:59 AM
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Restoration question from beginner
Hello All.
Just purchased an older black and white TV/radio/record player combo. RCA TA169. The guy I bought it from suggested it was working. He had it plugged in when I went to see. The TV did not come on (radio and recorder player worked). I did not want to pursue a restoration (by me or a shop) without knowing the picture tube is OK. The tube does have a faint light on the back when powered on and there is a bright dot on the screen when power is shut off. Is this an indication that the picture tube is OK? Thank you, Frank 
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#2
06-02-2020, 10:36 AM
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this is not, unfortunately, the only real way is to use a CRT tester.
__________________
=^-^= Yasashii yoru ni hitori utau uta. Asu wa kimi to utaou. Yume no tsubasa ni notte. いとおしい人のために
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#3
06-02-2020, 12:03 PM
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its not absolutely dead.
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#4
06-02-2020, 02:30 PM
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If it is a color set odds are the boost rect that suppose the G2 pots is bad or the circuits biasing the gun need work. The dot on screen indicates you have some HV and some CRT electron gun emission....If it is a rectangular CRT color set any other deltagun CRT the same size should be swappable...you could rob one from a common Zenith CCII or RCA XL-100 from the mid 70s (those sets can often be had nearly free). Note in 1968 the government passed law requiring tubes screen area be changed from bulb diagonal to viewable area diagonal. The numbers at the beginning of an alpha numerical CRT type ID number indicate screen size (typically in inches). So a 25AP22 from 1966 would become designated something like a 23VAP22....the first letter of 1968 and newer parts typically had a V to indicate viewable area measurement standard.
If rectangular color and you like the cabinet I'd go for it and keep an eye out for a spare CRT just in case. You really need a CRT tester or a friend with one when evaluating a set for purchase...There is a thread on ARFs TV section on how to do a crude test with a battery, DMM and a resistor. No matter what you test with knowing your tester is important....my B&K will show monochrome tubes that can produce a decent watchable picture at the top of bad and color tubes that are barely usable at the bottom of good.
__________________
Tom C. Zenith: The quality stays in EVEN after the name falls off! What I want. --> http://www.videokarma.org/showpost.p...62&postcount=4
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#5
06-02-2020, 07:52 PM
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No color in that set. According to radiomuseum.org, an RCA TA-169 was a TV/radio/phono combo with KCS43 TV chassis -- circa 1949 or so.
https://www.radiomuseum.org/r/rca_ta...43_rk135d.html If you don't have a CRT tester, perhaps there is someone from an area radio/TV collector club who could lend you his tester. Here's a list of clubs: http://antiqueradio.com/clublist.html Costs nothing to ask! Even if the nearest club isn't next door, they might know someone closer to you. Regards, Phil Nelson
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#6
06-02-2020, 07:56 PM
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16GP4 metal cone CRT. Beware. The entire metal cone is connected to around 12,000 volts. Stay clear when the set is turned on.
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#7
06-03-2020, 02:20 AM
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"Really need a CRT tester" is kind of misleading. When you test the tube and it shows 'dead' they will say that the tube is 'asleep' and you will not know for sure if the tube is good or bad until you have it plugged into a fully functioning set. Of course, if you had a fully functioning set, you wouldn't need a crt tester. So really, you don't need a crt tester.
As for the metal cone crt, here's another tip. They never test good. From my personal experience with two of them, they test dead or very weak, despite being ok. I've also seen this in a couple of shango's youtube videos, same thing. Also, common knowledge says that they are very rarely any good. Yet somehow I managed to get 2 good ones out of 2. I think where that comes from is that they probably test bad, but are not necessarily bad. There must be something about the metal cone tubes that don't test properly, or, perhaps, they can still make a decent picture despite being very worn out. My point is, testing the tube will yield no useful result. Unless, perhaps, you are such a seasoned repairman that you can divine the true meaning of the test results, be they bad or good. If you say the tv set will produce a white spot on the center of the screen, the crt is - at minimum - somewhat usable. Do not run the set for very long, the spot will burn into the screen. Last edited by MadMan; 06-03-2020 at 02:25 AM.
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#8
06-03-2020, 06:53 AM
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  Shango is an odd duck. I love his passion and enthusiasm but he's what we used to call a ham and egger. I stopped watching because he makes so many mistakes or says things that are factually incorrect. John
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#9
06-03-2020, 07:44 AM
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I still watch him as I find him amusing/ entertaining, but, he has gotten rather preachy a bit lately...
__________________
=^-^= Yasashii yoru ni hitori utau uta. Asu wa kimi to utaou. Yume no tsubasa ni notte. いとおしい人のために
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#10
06-03-2020, 08:04 AM
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#11
06-03-2020, 08:53 AM
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I don't believe that I have seen him bring things into good enough shape to put in his living room. Frank, that unit has a lot to it, a big project. The fact that it works as well as it does is rare for something so old. The date given in the Radio Museum could be off by the way, not everything at that site is accurate, but it is a good start. Be aware that TVs back then were watched in a dimly lit room, the screen was never as bright as modern sets. 1949/1950 was before stereo records come out, the phono cartridges (needles) will be hard on stereo records unless you change them out for stereo types. Don't run it until some restoration is done, otherwise hard to replace parts could be damaged. You can wake a CRT (picture tube) up by running it on a CRT tester for a half hour or more.
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#12
06-03-2020, 09:34 AM
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When he stuck that curtain needle hook in that ceramic cartridge on the 75 75rpm phonograph, I wanted to reach through my monitor and slap him into next week!  
__________________
=^-^= Yasashii yoru ni hitori utau uta. Asu wa kimi to utaou. Yume no tsubasa ni notte. いとおしい人のために
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#13
06-03-2020, 11:41 AM
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The shadow mask in color CRTs blocks ~80% of electron emission from reaching the phosphor so a tester designed to test color tubes will have the scale calibrated for color and monochrome tubes that have emission below what is good for color but reasonably above stone dead are usually watchable... knowing your tester and how it's readings correspond to actual performance on color and monochrome tubes is the difference between it being a rough guide/toy and an actual useful instrument. On that video where shango abused that record at least it was a home recording...those are generally worthless unless the person recorded has been identified as someone famous....the recording may have been priceless to the surviving family but when they allow such a record to leave their family it generally becomes worthless and lost forever. Shangos methods can be a bit unorthodox but on bad examples of sets that in some cases are barely worth using for parts he can't do much more harm beyond what time and neglect have already done. Depending on the vintage condition and intended use/desired reliability of a set I can respect doing the minimum to make something work....If you are only going to run something 5 minutes a year and it's a nice original example of the thing is a train wreck that isn't worth throwing spare change at a full recap/restore or even any work isn't necessarily needed. Sets of the 60s onwards have good enough caps that if they mostly work then it's perfectly fine to replace the minimum of parts to achieve proper opperation and leave all else alone.
__________________
Tom C. Zenith: The quality stays in EVEN after the name falls off! What I want. --> http://www.videokarma.org/showpost.p...62&postcount=4
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#14
06-03-2020, 12:46 PM
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I sorta want a CRT tester, probably woulda helped with that RCA I did back in Jan-Feb. The set works okay but has a weak jug. Goes silvery when you crank the brightness and takes a good while to get bright enough to watch. It still makes a watchable picture with the lights on so I can't complain too much.
As for Shango's methods, I aint even mad. He's able to do quick and dirty diagnosis without a shotgun recap. I've learned a bit by watching his channel. I usually fully recap my sets because I only have a few and I like to use 'em, also sometimes it just fixes mystery problems so I don't have to diagnose 
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#15
06-03-2020, 02:02 PM
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I have a bk precision 490b, but the damn thing lies to me...
It always worked fine with all sorts of mono tubes, and 25vxxx tubes and projector tubes, and so on. But when I hooked up my 21fjp22 that had been it storage forever,, VERY LOW emissions, scared the hell out of me, I thought the tube went dud in storage, took me a while to spot what was going on... heater V @ 4vac, barely, it could not put out enough power for the heaters in the CRT.  So, I got a 6v 3amp xfomer and it came right up into the "really good" range on all 3 guns... But, WTF? not enough power to light up a roundie? come on BK...
__________________
=^-^= Yasashii yoru ni hitori utau uta. Asu wa kimi to utaou. Yume no tsubasa ni notte. いとおしい人のために
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