Sylvania halolight combo!

[radiotron]

Originally Posted by ggregg

No they're not. How can a fifty plus year old cap be really strong? Run it till you fry it, I guess.

i have no clue, i checked some with a volt meter, and tested really close to what they were sopposed to be somebody could have replaced them in the past, but it was left plugged in for over 50 years, it was found in a falling down house

[N2IXK]

Originally Posted by radiotron

i have no clue, i checked some with a volt meter, and tested really close to what they were sopposed to be somebody could have replaced them in the past, but it was left plugged in for over 50 years, it was found in a falling down house

How does one check a capacitor with a voltmeter?

[radiotron]

Originally Posted by N2IXK

How does one check a capacitor with a voltmeter?

put it on the right ohms, and check their voltages.

[AiboPet]

I don't have an "ESR meter" yet, but was under the impression it takes one of these to actually check a capacitor. In school like 20 years ago, I remember we had an actual bench unit that was actually called a capacitor checker...I think Sencore comes to mind when remembering that thing. It would charge the cap and check for leakage, etc. This was just a "TV/Radio repair" class.....so even in the eighties I never got to work with any real vintage stuff.

I would be curious too how to use a regular Fluke or B&K DMM to check a capacitor.

[N2IXK]

Originally Posted by radiotron

put it on the right ohms, and check their voltages.

OK, how do you check voltages when the meter is on an ohms range?

And how does a voltage measurement tell you anything about the condition of a capacitor?

[josephdaniel]

A capacitor may test fine under very small voltages but begin to leak as more voltage is applyed wich it wat more voltage than a ohmmeter could ever supply.

[bandersen]

Right. You need to test caps for leakage at their rated voltage - typically 250, 400 or 600 VDC in vintage TVs. A device like this Simpson Capacohmeter can do pulse tests up to 900 VDC.

[n2bew]

Originally Posted by Username1

It certainly looks better than sets I have seen for $50. or more.... CL Often has some good finds.

Well, I am off in the morning to pick it up. I live within 20 miles and had contacted the guy as soon as it showed up on CL in my area. I will post pictures when I get it and report on condition. ( I will start a new thread when I do so as to not hijack this one) Hope you guys are not too upset that I got it if someone had their sights on it.

At least you will know I will plan on restoring it and it won't end up a fish tank or worse.

By the way I am new to VK and have only posted a few times so thought I would say hello. My name is Tom and I have been only restoring radios the past year and I am just getting started with TV's. Having lots of fun so far and glad I found this forum thanks to Bob "bandersentv" mentioning it on his YouTube channel. I also have to give Bob the credit for getting me interested in TV's in the first place through his YouTube channel. I never even thought about restoring TV's and then after seeing Bob's restorations of them got hooked rather quickly.
This Halo will be only my third set that includes a little GE 1956 portable and an Admiral 24a12 that also showed up on CL in my area, I had to pay for the Admiral, but am glad I did!
So far I have only checked the CRT's with my B&K and done a light cleaning of the sets, and started taking the G.E. appart to recap it. I'm married and have kids at home so have to squeeze in time for the hobby when I can, which is not much. I hope to do more over the winter on these.

Tom B.

[DavGoodlin]

Originally Posted by n2bew

..............................
So far I have only checked the CRT's with my B&K and done a light cleaning of the sets, and started taking the G.E. appart to recap it. I'm married and have kids at home so have to squeeze in time for the hobby when I can, which is not much. I hope to do more over the winter on these.

Tom B.

I have the same scene. Fortunately storage is not an issue but time really is. I just have to make up my mind what to work on with that limited time. I decided on the Sylvania 21C528W Halo I just got. I get up extra early just so I can get a half hour in before leaving for work. I cooked the CRT (at 6.3v) on my tester for that 30 minutes each of the last 3 days and it moved from .5 to 6, on a 0-10 scale. This morning I pulled the tubes and will test them while doing laundry tonight. The capacitors are VERY suspicious looking, so I will pull the two-section chassis and bring half into work for a lunchtime re-cap. I have even been restoring radios at my desk over lunch. Do what you have to do. My goal is to have the set looking good enough to bring in the house and watch Twilight Zone DVDs on it.

[Phil Nelson]

Originally Posted by DavGoodlin

The capacitors are VERY suspicious looking

The appearance of old paper and electrolytic caps is not a good guide to their internal condition. (They can look great outside but be garbage inside.) They are so often bad that most restorers replace them without question. This article has info about recapping:

http://antiqueradio.org/recap.htm

Have fun!

Phil Nelson
Phil's Old Radios
http://antiqueradio.org/index.html

[radiotron]

Originally Posted by Phil Nelson

The appearance of old paper and electrolytic caps is not a good guide to their internal condition. (They can look great outside but be garbage inside.) They are so often bad that most restorers replace them without question. This article has info about recapping:

http://antiqueradio.org/recap.htm

Have fun!

Phil Nelson
Phil's Old Radios
http://antiqueradio.org/index.html

thanks that helped a lot

[radiotron]

Originally Posted by jr_tech

Type 5642 HV diodes:

http://www.r-type.org/exhib/aai0016.htm

Widely used in Tektronix oscilloscopes of the era, and a few TVs.

Here are a few on the 'bay:

http://www.ebay.com/sch/i.html?_trks...diode&_sacat=0

Not affiliated,
jr

if these go bad can the tv humm like its bad caps? (yes i know not to turn the tv on)

[N2IXK]

A bad HV rectifier tube would cause no high voltage, resulting in no light on the screen. A weak tube would cause low HV, resulting in a dim, poorly focused image and /or blooming (image size changes with brightness).

BTW, bad capacitors can cause all kinds of symptoms (depending on what capacitor is bad in what circuit), not just a hum.

[Electronic M]

TVs can also hum from a non-capacitor related issue known as intercarrier buzz. That buzz can not be fixed with caps and sometimes simply can't be fixed. If there is constant hum regardless of wheather the set is connected to a signal suspect caps, but if the buzz comes and goes with picture content(high contrast lettering tends to make really loud buzz) then it is the intercarrier buzz that is normal on many sets. The buzz and hum sound similar, but different so with experience one can tell which it is by ear.

[AiboPet]

The little cheap chinese b/w sets I have so many of VERY often have this intercarrier buzz.