Westinghouse TV Fixed!
 

I was driving around with my girlfriend when I spotted a 19 inch (i'd say) westinghouse B&W tube tv. With my favorite word on it "Free".
So I took it in a heartbeat and took it home. Upon inspection everything seemed Ok (nothing was leaking blown up or covered in strange resin). Today I tested all the tubes except the half wave rectifier tube. They were all in the green except 2. One sorta jumped around the other was just a little weak(These were small tubes) I also didnt check the two tunning tubes as they were in the back and I was unsure of when it was last plugged in. (The tv has a total of 20 tubes including the picture tube.)

After this I had to at least try it out

I decided to plug it in. And i'm pretty sure all the tubes were glowing including the projection tube(Scary damn thing xxxradiationxxx) But after about 20 seconds nothing. No sound, no picture I flipped through the channels and nothing. I was dissapointed, but I knew it wouldn't work when I found it.

So any one have any suggestions for me. Little things to check. In an attempt to track down the problem. I don't wanna spend any money on this tv. Its big sorta ugly and a B&W radiation machine. But if i could see it turn on once that would be cool.

Or should I just screw it, and rip it all apart take all the chokes and audio transformers. And anything else you think would be useful?

It has a 21alp4a Picture tube. If that helps anyone on getting an idea of the size and type of tv. It also has 13 channels if that helps put a date on it.

Thanx. and if anyone wants to see a picture just ask I'll do it No worries. Ask any questions you want.

Oh and I own a didgital voltmeter :) handles 1000volts and doesnt measure capacitances.
So thats my other testing supplies other than my tube tester. Which is a Dyna jet model 606 Any1 know if its any good? I also got it free :)

you will have to replace the wax capacitors and then check for open/drifted resistors before all

If you dismantle the set, i'd also keep the tubes and the speaker

Anyway, a B&W TV emits little if any harmful radiation.

You think maybe if I hit it a couple times....haha its a long shot but i did notice solder balls and bits inside the frame . Ha I just can't bring myself to strip it just yet

Don't do it!

Sounds like the B+ isn't running. Check for a fuse or circuit breaker. I'm gonna guess it's a series-string set. (would use odd number tubes, starting with numbers like 7, 8, 11, 13, not all 6's and 12's)

Don't strip it!!

It minimum it will need new capacitors to function properly. THe westinghouse sets usually had a large sand-type dropping resistor in the B+ supply that would go up in value or open, preventing operation of the set other than the tubes lighting.

You will want to replace the electrolytic capacitors in the power supply, as well as all paper capacitors. See http://antiqueradio.org/recap.htm for basic advice on that.

If you can find a label anywhere with the model number (http://antiqueradio.org/identify.htm), perhaps someone can send you a scan of the schematic for this set. I wouldn't try to restore any old tube TV without a schematic, since it involves replacing dozens of components, with many opportunities for making wiring mistakes.

There is no danger from radiation. But be careful not to stick your fingers into the chassis if you have it powered up on the workbench (which might kill you or kick your butt across the workshop).

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

Don't strip it !
Rather than strip it , give it to someone who would enjoy doing a restoration .
If you want to get it going , expect to do a recap as everyone else has also said .
Most likely the it would operate with the original electrolytics cans , however the wax/paper caps will all have leakage .
And also I have found that the early plastic covered caps , like "SANGAMO" brand are also leaking .
The parts most likely wouldn't cost you more than $30.00 .
I would keep it , and do a recap on it.
As for radiation , the amount produced by a B&W television is very low .
I have had my head stuck in TV's off and on for the last 20 years , and Im still here . :yes:

how dead could the picture tube possibly be though. If this is dead I may have no hope of fixing it. Or would it still work and have a weak picture?
I think it might be dead because all the tubes are in good condition except two, which I think would still at least get it to show picture.

I have no money right now to replace the capacitors but it does sound like a fun job. I guess I will try and check the B + supply tomorrow and its resistor for starters. Would taking the chassis out help me, I don't really wanna do to much unnecessary stuff. That might break it :S

Oh...and if I touched what I thought was the positive side of a large diode (Its blue with heat vents I know its a diode)with my voltmeter and the other end to the chassis should it of given me a large DC voltage? Possibly for the Picture tube or other tubes B+ supply?

Or would this B+ voltage more likely be rectified in an actual tube, Half wave or Other?

And am I looking for the B+ to the picture tube or all the other tubes. I don't know much about tv's but have sorta made some tube amps. And learning is fun.:thmbsp:

With the symptoms you are describing, this TV most likely had a power supply
failure a long time ago and was set aside. Ther is no reason to conclude without
some testing that the picture tube is dead.

The thing you are describing as a large blue diode with vents is most likely a selenium
rectifier for the power supply. Do a little research and you will find out that those
are prone to failure and are usually replaced by more modern silicon units.

Be very careful, but working on this TV should be a rewarding experience.

As someone else suggested, if you could post some extra info, it would help us
to help you. Things such as model number, list of tubes, etc.

The 21ALP4 picture tube type indicates that this is nominally a 21-inch TV.

Good luck, please do keep us posted.

Does the cabinet look like this one? http://www.geocities.com/wa2ise/radios/west-tv.jpg

Alright i'll have a picture of this tv Both outside and inside in half an hour along with a list of tubes and there purpose in this Tv

THe cabinet you showed me is pretty close but it doesn't have that nice colour. Theres a lot more brown detail. But yes the cloth on the bottom and controls at the top.

Pictures soon!

Just can't wait!

K for some reason it doesn't wanna let me upload my pictures so I guess I'll just type what I got. The model Number is either 5-3533 or it's 65j 941-1.

4bq7a Rf amplifier
5at8 Mixer
3cb6 1st pix I.F. and another for 2nd pix I.F.
5am8 3rd pix I.F. + 2 DET
12by7a video amplifier
21alp4a pix tube
3au6 sound I.F.
3al5 FM detector
3av6 Audio detector
12c5 audio output
3au6 keyed AGC
7au7 sync amp/noise killer
5u8 sync.sep/vert discharge
12b4a Vertical output
3al5 horizantal phase detector
7au7 horiz oscillator
12bq6gtb horiz ouput
1x2b h.V. rectifier
12ax4gta damper

and i'll try to get those pictures posted as soon as it starts working.

It's a Christmas Miracle!

PICTURES!

Do I see the French word AVIS (meaning warning) on the metal cover in the upper
right corner? This could be a Canadian made set, or one marketed under the
same model number in Canada.

As was expected, this is a series string set, meaning that the designers did away
with a power transformer, and that most tube heaters are wired in series. If
any of those heaters fails, the tubes won't light up, but you already checked that.

If you undertake removing the chassis (a step that is almost mandatory to do
some serious repairs such as replacing the filter capacitors), be very careful with
the following: the picture tube base may have unglued from the glass, and pulling
the socket to remove it could just tear the base away, break the fine wires and
possibly destroy the tube. Always make sure that connections between the
various parts of the system are properly undone before you pull out anything.

Series string sets are somewhat trickier to service than those with a transformer,
but they are capable of good performance.

Good luck.

P.S.: If this is indeed a Canadian market set, give me until next Monday
to find a schematic for you. I might have it.

Actually your right. The Tv was made in Montreal apparently. I thought that was pretty cool.
If you could find a schem that would be great...Thanks
Rudy

I've taken the set out of the box to get a better look at it. And have some more pictures of some parts. Like one part that I think is the "sand resistor" (only measured 25 ohms) and it was physically chipped. Also I found one of the only looking possibly burnt capacitors. It is conneceted to the 1x2b and just looked charred black near the bottom. Check it out. Is this a good spot to start.?

I've also been checking random resisitors and all of ones near the burnt cap. They all seem OK....not perfect but close enough to what they should be. Are the resistors normally Ok in older TV's?

Now to test for the B+ supply for the tubes what should I do. Plug it in with a voltmeter hooked up to the larger capacitors. Or how? should I go about this. With my little tube amps this was fine But they don't make voltages in the quadrupal digits.

The B+ in those sets runs somewhere between 375 and 500v. YOu need some service literature like a sams photofact to tell you what the voltage measurements should be.

Just measure between the terminals of the filter caps and ground. Look for excessive AC voltages at the caps too. That usually indicates a leaky or open capacitor.

On a "dead" set--i.e. no picture and no hum in the speaker, but tubes all lit, it is usually failed B+ off those two blue selenium diodes. With the set unplugged arrange an alligator clip hook up at one of the twist-lok tabs where the common negative should be. It might be directly connected to the chassis pan, but sometimes a maker will get weird and isolate the pan. Clip the other end of the alligator jumper to the negative test lead of your meter, and set it so that it can read up to 500-600volts. Plug in the set and fire it up, and you can quickly ascertain whether or not there is B+ present at the voltage doubler circuit comprised of the two blue rectifiers. It'll be around 300 volts usually.

If there is voltage present then listen to the "doghouse" of the set and--if you have young and healthy ears--determine if you can hear a dog-whistle high pitched sound indicating horizontal sweep. If there is then you may see some boosted B+ sweep-signal-derived off the damper tube and a winding of the flyback coil--about 400 to 500 volts. If you are not hearing the 15.75KHz whistle then have a quick look at the anode of the horizontal output tube to see if its plates might be turning red from lack of drive-induced negative grid bias. Pull the plug if it is, or lose the tube, or perhaps blow a fuse. In fact staring at the plate of the 12BQ6 should be the first thing you do after powering up; if there is no drive the tube can go up quickly.

If there is no boosted B+ then in some sets there is no audio either, as the sound output tube draws from boosted B+ and "moonlights" as a voltage regulator, feeding about 130 volts off its cathode to such as the IF stages and the tuner. Thus there will be little or no action from the set at all.

You may already know these things, but.... Left hand in pocket is a good rule. Places not to go with your voltmeter test prod are anywhere within the "doghouse" (high voltage cage), the heavy lead running to the anode well on the back of the picture tube, the anode cap of the horizontal output tube and the anode pin of the vertical output tube.

Also--like the rule about loaded/unloaded guns--there is no such thing as a fully-discharged kinescope (picture tube)!!!! They make a very efficient capacitor, and can hold a charge for decades. AMHIK.

There is no hum Or red glowing tubes that are being overloaded i'm almost sure. The set literally gives no action other than tubes all glowing red. I will go test the selenium rectifier momentarily to see if it is truly failed.

And THANK YOU for the warning about the DOGHOUSE. I was poking around in there two days ago :S. Not for voltages but just to test the tube. Thank God I was being careful.

......and all you guys Thanks
I was gonna just strip this thing when I found it, and probobly would have. But now that I know theres hope I have this dieing urge to play my nintendo and atari on it :P

There DEAD, there really dead.

From the chassis(witch the selenium rectifier's ground was directly soldered to) The possitive side of the selenium rect shows a peak voltage of 30 dc. The other one shows a whopping 5.

So is this where the B+ originates from? DO the other B+ just get stepped up from the volatges made in the selen. rect?

So I'm guessing I need that for sure. But what will I be replacing it with? Another selnium one that's the same. Or is there a better new diode used when replacing these old ones cause I don't know first hand. This is also my first TV repair job, and I'm lovin it.

Rudy

Alright I have 2 or possibly more 6a2 diodes. I think they are rated at 6amps 200 volts. And I know I built a 250 volt power supply from them. Would this be sufficient as a replacement. Cause from what I read the selenium are much larger than the silicon ones. So maybe these two guys would work? They are about 1 cm long and .7 cm in diameter.
Like I said I have no money so I wanna do anything I can with what I've got. (.91 cm x .91 cm actually)


And If I do have more than one can I double them up or put them in series to increase the voltage they can handle? I know it can be done with a cap

And one more question. The caps in this TV do you think there full of PBCs. Or is there no doubt they are

Those selenium rectifiers are probably rated maybe 1/2 amp. Voltage I'm not so sure about though. Probably you'd want something to handle a little more than 200. I used 1N4007's to replace the selenum stacks in my Philco.

PCBs are usually found in oils. THose caps are mostly paper and foil. The electrolytics have some sort of borate in them usually, no PCBs. THe rest are dry (well, other than the water they've sucked up over the last half century)

Handy tip for testing the HV lead. Use one of those compact flourescent lamps or even a small flourescent tube held near the HV wire. If it glows, you have high voltage. Don't get your fingers too close to this, the HV lead probably runs 15,000 volts or so.

That's a handy trick I must say.
I guess i'll go grab a diode tomorrow. I'm sure I can scrounge 50 cents.
Then do you guys think I should give it a whirl..or no?

A good diode to use is the common 2.5A 1000PIV silicon type. Also any associated electrolytic capacitors in the voltage doubler circuit are likely dried open, hence your low voltage readings. Be sure the working voltage ratings of the replacement capacitors are the same or higher than the originals. Series hookups of capacitors can be done to increase working voltage ratings, but shunt resistors of about 220K ohms and 2watt or better should be used, as no 2 electrolytics have the same leakage, and one will almost always hog all the voltage from the other. Generally it is a better practice to avoid series connection, but paralleling them is OK to increase total capacitance, provided all the caps are of the appropriate voltage rating.


Make sure you get the polarity correct on all those diodes and capacitors....unless you like extreme excitement....

A source of diodes and caps would be old PC power supplies. They usually have doubling power supply circuits on the line side.

Thank you wa2ise,
You made me remember I had an old fried superbrain charger. Full of diodes. Turns out they are 6a10 much like the other ones I had but rated for 1000 Volts! 6 amps
I'm gonna go put them in now

so the diodes are in. I also left the old ones in but disconneceted them from the circuit. Looks cool.
And if I am correct I wanted the stripe of the diode (cathode) To be connecetd to the + side of the capacitor?

Well I'm gonna test it. After I build a bombshelter around it. If you don't hear from me again.....Tubes Rule! :P

Alright so I put the diodes in, No issues. And booted it up. And once again was left with about 30 volts Then when the heaters finished heating it dropped.
I traced where the ac mains lines actually go and one goes to the damper tube base. But is not actually connected to the tube. Its connected to a sand resistor. Some one else mentioned it could have been this resistor.
I measured in this resistor at 25 ohms. Is this an average value for this type of resistor or is it wayy off?

The other mains goes to ground then the one of the new diodes I put in.
Also one side of the mains is hooked up to a small cap then travels to another larger cap. To ground again..I think

Make sure they are in correctly ....

25 ohms sound alright to me , I have a bit different westinghouse schematic , and there is a 7.5 ohm , them the cap , then the diode .
Does the resistor look burned , or have cracks in it ?

I'm almost positive I have them in right. I get just about the same voltage as before with the originals in. Just a little better. SO i think I got that part right.

But the electrolytics are dead is the real problem. It charges up to 30 then drops to 3 volts when I turn it off. It should be staying closer to 30 for longer should it not?

Anyone think replacing them would solve the problem?

Yes I beleive i have a picture of it posted. It has a chip on one side. I'm not sure if its the kinda chip that affects performance But i'm hoping it might be.
I wouldn't say it looks burnt or anything else though.

If you havent' already replaced the electrolytics, that is surely adding to your problem, along with bad paper capacitors.
I just don't understand how it is people take un restored stuff and put so much faith in it working.
Bill Cahill

Those sand resistors are combination resistor and fuse. "Fuseistor". Most of these I've seen are on the order of 7 ohms. You should see a number printed on it, that number is usually the resistance.

The rectifier circuit sounds like a doubler. One of the mains (powerline) going to ground, the other mains line going to an electroytic capacitor. The other side of that cap has a diode, the other end (its anode) of which going to ground. And a 2nd diode, where the 1st diode connects to the cap, the other end (its cathode) of the 2nd diode feeds a second electroytic cap, the other end of ths cap goes to ground.

Selenium rectifiers usually had "+" marked on their cathodes, as if to say, "apply AC to the other end, and here you will get positive voltage".

Yes it is a voltage doubler working as you described.
And as for the sand resistor it has the number 2 on it. And I thought it may be an ampere rating cause like you said "Fuseistor". And if it is supposed to actually be 2 ohms it is 23 ohms off.

Is there a possibilty that this sand resistor is actually for the heaters. I sorta traced where it goes. It went to hz deflector tube (12bq6gtb) and definatley connected to pins 7 and six (7 is heater connection 6 is blank)

Does anyone think that a recapp is all she needs and would bring this tv back from the dead? Or would it still most likely need further work?

As someone who has repaired many a b&w tv the first thing I suspect is the high voltage(about 20kv @1ma).If you touch it you will live(unless you have a pacemaker:D)Its like getting shocked with a sparkplug wire.I know a way to check th high voltage with a screwdriver but I'm wary of telling you how in case something happens to you. These tv get dust inside and it doesn't take much to overload the H.V. You could try cleaning around the H.V.(its the part of the tv with all the dust around it.The high voltage attracts dust like an electrostatic air cleaner.If the horizontal flyback transformer is gone(part of h.v.)then its a lost cause.Be careful as some chassis were conected directly to one side of the a/c line so depending on which way the plug is in the wall the chassis may be live or not.The value of doing this is not n the tv but in the learning experience of trouble shooting.Good luck and be careful:yes: