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Well t me that is, Just bought a radio from a guy in washington. Electrically it is supposed to be pretty complete, minus one tube. I plan to get it home and then Refurbish it following the work denny graham did in a post here, and then returning it to service in my 3600. I can't wait.
I will be posting questions as I go, which will be next week sometime.

What is the fellow's name that you bought it from?

Faulkner auto radio in washinton state- the guy bought faulkner's store out and it had numerous old radios and parts. He could not find the one missing tube in all the parts, it is a OZ4 tube. All of the rest of the parts and components look good. I will post some pics later. I plan to replace the tube with the solid state stuff. Dial and push buttons all work. Paint is good. It is just a little dusty. The Paper sticker on the inside back cover is good as well. It is a model number 986443 with a flat back. and The paper is how I figured out what Tube I am missing.
Any advice up front?

If you don't really want to replace the tube with solid state I was looking through JC's catalog and he stocks OZ4 tubes, just so you know.

Well what I am really looking for is (a prayer!) actually a manual to help walk me through testing and the like, I am not very electrical, but I am somewhat so I would like to give it a go. The glass tubes on the inside have different amounts of shiny "metal" looks to them in various amounts. Some don't have the mirror look much at all. Is there a way to test these?
An as far as making a power source using a trickle charger- How do I hook that up?
I am thinking of finding a repair service to overhaul it- But leave it all original, no gutting, no fm, I want an original working radio. any suggestions?
Thanks all

Ok so in the last post i asked a bunch of questions before searching.
Now I have searched. I would like some details on wiring up the trickle charger. I think we should post the test setup in Tech tips- especially a safe test set up with the one hand in pocket thing.

On the wiring, how do you hook up the wires to the actual radio, and the insulated wire, like a 5 foot piece of regular insulated wire?
Thanks all, I know I can be a pain.

Yelostn78,
if you look in the tips section, you will see that I have a writeup on how to test it without doing damage. As far as hooking it up, connect the black lead of the trickle charger (6 Amp) to the chassis and the red clip to the power lead on the radio. Plug in a car radio antenna and that is it for the connections. You can substitute for the antenna with a 3 foot piece of hookup wire with about 3/8" stripped bare. Insert that end into the tiny hole in the antenna socket.

These radios are quite valuable even in the unrestored state.

By the way, some of the vendors are selling "new" OZ4s which are really a solid state conversion. As far as testing tubes, normally one would use a tube tester. However that may only be necessary if you suspect one has a problem.

I would be happy to answer any questions and help guide you through the trouble shooting and repair.

FWIW, the vibrator will go out first on these old radios and you can get them (solid state at RADIO DAZE...www.radiodaze.com) as replacements. They also have any tube that you may want. I replaced the vibrator tube along with other tubes (from RADIO DAZE) on mine and it is working fine. Also the on/off switch is a weak link on these radios. You should check if the on/off switch is working as desinged before replacing anything. And then my all means replace the vibrator!!

Thanks for the info- I am really excited about getting this thing working, It will go in my 3/4 ton, because it had every option. Can't wait to test it and see if I get some lit up tubes.

When you get working on it, I can explain how to test the vibrator. If you purchase a new solid state vibrator, you should make sure that all the capacitors are replaced or in good shape before plugging in the solid state vibrator. They can be easily burned out. Also they are polarity specific, that is there is a different solid state one for positive ground and negative ground.

truckernix brings up a good point about the capacitors, I would personally replace them when installing a new vibrator (solid state or other wise). turkernix also brings up another good point, the vibrators are polarity sensitive, [b][i]ALL[/b][/i] Chevy trucks are negative ground and the early GMC trucks were positive ground (thru 1970 or longer). So, make sure you get the correct vibrator polarity for you specific radio.

Thanks all, upon closer inspection, the vibrator is solid state, some of the capacitors have been replaced with modern plastic looking ones, the wiring is still cloth braided, but really clean. The one tube that looked burned out is actually black about 2/3 of the way down then clear. Thanks for the tip on the ebay booklet.
I also ordered the reproduction harness for the truck side of the radio and I ordered the oz4 tube. I plan to pull the vibrator and do a basic test of the radio as described using the trickle charger(6V) with a fuse in the positive lead. When do I connect the negative, to the case of the radio?

Sorry I have not loaded any pics yet, left the camera in my modern truck which is at the storage barn because my 1/2 ton is in the garage.
But they are coming.

The maroon plastic is pretty faded and looks kind of pink/purplish, so those might get replaced, we will see.

Thanks for all the help as always.

The black lead goes to the case. I assume that this radio was used in a Chevrolet or negative ground truck. If the solid state vibrator is made for a positive ground, then that is the only way that particular vibrator will work.

The new bezels that I have bought are a much darker than the original. Personally if the bezel is still good, I like to paint them the original color.

I agree on the bezel part, these are much more burgandy color, albeit very faded, the newer replacements are almost brown looking.

Ok got my Oz4 tube, it is installed, the vibrator is kind of hard to get out. The light in the radio works when you touch it's power wire to a 6v battery and ground the case.
I am going to try testing tonight with a charger. I am going to stop at radio shack tonight. I am picking up an inline fuse adapter- which size should I get? fuse that is 15? I will check the manual in a moment. I am going to connect the fused positive line to the positive alligator clip on the charger and the negative I will connect to a louver on the radio case- I am then going to try and get the vibrator(solid state) out then turn on the radio. Should I just put a bare end of an insulated wire in the antenna port?
Thanks all. very excited.
I will let you know how it works out.

Those vibrators can be tough to get out. With the old ones, a pair of channel locks will do the job but the new ones have a very thin case and they crumple quite easily. It sounds like your radio has been already restored so I would just go for it. If your trickle charger can only supply about 6 to 8 amps then you don't realy need a fuse. For installation, a 14 amp fuse will do fine. When those radios are first turned on, there is an initial surge of current through the tube heaters because they are cold. For this reason, a fuse a little larger than the working current is used.

Thanks for the info, got it powered up, all the glass tubes but one light up. it is the one kind of towards the middle, I will have the exact tube number for you tomorrow. The speaker makes a humming noise that is only altered by turning the three position switch behind the volume knob. I have a wire in the antenna port but it has not made any difference and I cannot pick up any stations yet. of course that might change when I move from the basement to the upstairs.
Very exciting.

Thanks for the info, got it powered up, all the glass tubes but one light up. it is the one kind of towards the middle, I will have the exact tube number for you tomorrow. The speaker makes a humming noise that is only altered by turning the three position switch behind the volume knob. I have a wire in the antenna port but it has not made any difference and I cannot pick up any stations yet. of course that might change when I move from the basement to the upstairs.
Very exciting.

I will just check on something here. The small wire for the antenna should have the 1/4" bared section inserted in the small hole inside the antenna socket. That hole is about 1/8" in diameter, or less. Most likely from what you have said so far, the audio section is working and so is the main power supply. Also, is the tube that is not lit up warm to the touch?

Someone more knowledgible will jump in, I'm sure...
But the Speaker has to be a certain Ohm Rating to work....I believe....

The tube is warm to the touch, just not lit, I am trying the wire, does the opposite end of the "antenna" wire (far away from radio also need to be uncovered, or just the end inserted into the antenna port?

ok after it has sat with power on and warmed up the noise begins to kind of pulse, at varying speeds that I have no control over. I can control volume of the noise by rotating the three position selector, but one position is quiet and two equally loud. Volume knob makes no noticeable changes other than to power on/off. I have been turning the tuner know up and down the scale while turning the three position at the end of the dial. No changes. Thanks for any help and advice in advance.

OK, if I were troubleshooting the radio , here is what I would do next.

First, on the straight back radio, I would remove the front cover. This would also mean disconnectng the speaker and reconnecting it with jumpers. Next I would use a voltmeter to check certain areas of the circuit. It is handy but not essential to have a tube tester. A spare set of tubes can do the job too. Also, you would need a copy of the circuit. I can Email you a copy if you need one. If you want to proceed, I can help to giude you through the process. Otherwise at this point, I would suggest taking it to a repair shop.

I actually bought the repair manual with circuit diagrams and such. And I want to repair it myself. That way in 20-30 years I can do this again with my Kids- Plus, I doubt any of us will be able to find repair shops for old tube radio at that time.
When I disconnect the speaker- can I use small alligator clips on each end of wires for jumpers?

Yelostn78,
You can use jumpers or wires with alligator clips. That is how I do it. You may find the speaker plug very fragile. If it breaks it can be replaced with wire joiner plugs and I can explain how to do that.

Fred

Cool, I am fabbing one up later tonight. I am waiting for a new 6v6gt tube. the old one was the one that did not light up, The warmth I was feeling was ambient. So I ordered on to be on the safe side. It gets here friday. I also ordered the #28 capacitor, as recommended by the guys an antique radio forum. I will put it in when it comes in. I will definately let you know. So far everything seems in great shape. I would almost put it on par with my 1985 ford radio that I had to change the internal dial light bulb in. very clean. The electrolytic capacitors seem kind of tacky- sticky- they look saturated with something as I think they are supposed to be, not to dry out, in fact all of the paper type seem saturated, not all of them are tacky though. My current plans are to wait for the tube, try it, and then move on to the next item. Thanks for all the help, I will keep posting questions. Oh here is one, do you think I should install all the noise stuff in the install book, or get the coil, the distributor, the generator first and try it?

Yelostn78,
I was under the impression that all the capacitors had been replaced. If I were working on it, I would not proceed until all the paper capacitors ( the wax covered ones) and the electrolytics which are in the can next to the OZ4, were replaced.

Your 6V6 tube must have been working to some degree because that is what drives the speaker output.

If you have the straight back radio, the diagram for your radio does not have a capacitor #28. That diagram is for the slant back radio and they are different.

Something that I meant to mention is that there is a possibility that the previous owner installed some of the tubes in the wrong sockets. You might want to check for that.

Here is how you can start checking to see where the radio is failing:

Take a piece of hook up wire, maybe a foot or so long and strip bare about 1/8" on one end. Now with the radio powered up and the volume turned up, touch the bare end to pin 5 on the 6V6, a few times. This should produce a scratching noise. Now work back and do the same on pin 2 of V4 the 6SQ7. Next try this on pin 4 of V3 , 6SK7. Next try pin 5 of V2, 6SA7 and then pin 4 of V1, 6SK7.
Let me know where the signal injection fails.

By the way the pins are counted from the bottom, in a clockwise direction from the central key.

Mine does have a #28 it is referred in the photofact folder as the c14 capacitor- which it shows having a value of .006 cap. and 1600volt, chevy part number h602.
I told you wrong on the 6v6gt,
It was the 6sk7 and the 6sa7 that were reversed and the 6sk7 is the one that does not light up and barely gets warm.

So I am going to begin to order my capacitors. Is there any preferred brand, the sprague orange seem pretty popular, but they seem to only off the kind with the contacts coming from the side and not the ends. I am going to pick up one of the finer tipped soldering irons because my pistol type seems a little bulky for the job.
My plan is to to go through changing them one at a time does it matter what direction the capacitor is installed? I would think they are bi-directional.

Oh, and does that change the testing procedure you requested with the bare end wire on the tube ends?

Yelostn78,
if you want to try testing again, there is probably no harm in trying again but the results would not be meaningful.

For most of the capacitors, you probably will be OK with something common like the "orange dips". You need to have the voltage rating at least as high as the original and the polarity of the new ones won't matter. The black stripe goes to the negative side, if you are curious.

The electrolytics are a different case. In this case the polarity matters. The three main electrolytics in your radio are contained in a metal can next to the OZ4. I would leave the can in place and disconnect the non grounded connections from it. The new electrolytics will be connected in their place. Please look at the photos of these two radios on Ebay. It will show you how it is done.

http://cgi.ebay.com/ebaymotors/Parts-Accessories___Fully-Restored-47-53-Original-Chevy-GMC-Truck-Radio_W0QQitemZ260333035153QQddnZPartsQ20Q26Q20AccessoriesQQddiZ2811QQcmdZViewItemQQptZMotors_Car_Truck_Parts_Accessories?hash=item260333035153&_trksid=p4506.c0.m245&_trkparms=72%3A543%7C65%3A12%7C39%3A1%7C240%3A1318

http://cgi.ebay.com/ebaymotors/Parts-Accessories___1947-48-49-50-51-52-53-CHEVROLET-TRUCK-RADIO_W0QQitemZ120347487703QQddnZPartsQ20Q26Q20AccessoriesQQddiZ2811QQcmdZViewItemQQptZMotors_Car_Truck_Parts_Accessories?hash=item120347487703&_trksid=p4506.c0.m245&_trkparms=72%3A543%7C65%3A12%7C39%3A1%7C240%3A1318

Fred

Ok I understand on the positive negative side of the capacitors now, I am looking at the schematic and seeing them. I will run the tests and let you know what happens.
Sam

Ok wire testing complete
I started with radio on, volume at half. The three position switch in the middle position, tuner needle about half way.

on V1 6SK7 nothing happened on any pin

on V2 6SA7 nothing happened on any pin

on V3 6SK7 Nothing happened on any pin

on V4 6SQ7 on the first pin from the bottom(bottom of radio side) to the left going clockwise mad a different tone that could be volume adjusted(kind of line a guitar amp
the 3rd pin from the bottom left side also did the same, but slightly higher pitch

On V5 6V6GT a single click could be heard through the speaker once every four or five touches of the wire on pin number 4 from bottom left going clockwise(top left pin)

Oh mighty radio Guru, please decipher this code from a foreign land!

OK, now we know something about the radio. The first thing to do is interchange the two 6SK7s and see if the test on V3 changes. Also it would be good to check a few voltages. If you look at the schematic, you will see what looks like an inverted T at the top of each tube. This is called the plate and that is where the highest voltage in the tube usually appears. So it would be a measurment between chassis and these points as follows:
V1 pin8, V2 pin3, V3 pin 8, V4 pin 6 and V5 pin 3. Your meter would be set to DC volts with a range of 300 volts or greater.
I should emphasize that you don't want to come in contact with these voltages!

ok when I changed the two around, now when I touch the wire to pin 1(again bottom left(7'clock position) with the wire I can hear music, scratchy from poor quality antenna I think, but music(acutally sportstalk 810am kansas city. So is it a tube?

i am going to do the rest of the testing now.

It would be good to try the injection test again on V2, 6SA7. If you get results there but you cannot get anything with the antenna, I would suspect that the 6SK7, now in V1 position is weak.

I get music when touching the 6SA7 comes in just as clear as on the 6SK7
I get a replacement on Friday, I will let you know how it goes, In the meantime, I am still wanting to replace some of the capacitors, I am having trouble finding all of them on line, most are 500 or 450, not many 400 hundreds, any advice?

I wouldn't bother with the small mica ones, just the yellow waxy ones and the electrolytics in the can next to the OZ4. Also, the one you mentioned is quite important.

I use this guy and find his service excellent. He has a nice explanation of what types you should use etc. His site is worth looking at just for learning purposes.


http://www.geocities.com/justradios/aboutjustradios.html

When replacing the capacitors, sometimes the new ones are much smaller than the old ones and you end up with long exposed leads. In these situations, I use some insulation stripped from hookup wire to cover the leads.

Thanks for all the help, I am sure I will have more questions, and I will let you know the results of the new tubes.
Sam