[klondike98]

Picked this General Television set up and have now opened it up to try and figure out what model I'm working on. Its tube set is:
12A8GT, 12K7GT, 12Q7GT, 50L6G, 35Z5G

[Image: https://www.dropbox.com/s/4ibmwv71wd3spl....jpg?raw=1]

I have located schematics for General Television radios with that tube set and chassis layout that indicate possible model numbers 19, 51, 511A and 521. Unfortunately I have not located any photos of these models but probably have enough information to be able to recap, align, etc. If anyone happens to have more info please let me know.

Here is the model 19, 51 schematic.
More later...

[klondike98]

Its a cute little set that's in relatively good shape.  I particularly like the colorful dial.
[Image: https://www.dropbox.com/s/az675dumf9wpkv....jpg?raw=1]

The chassis is actually completely metal encased.  Here is the underside with the bottom of the case off.
[Image: https://www.dropbox.com/s/zfunf21ns3ux6r....jpg?raw=1]

The homemade back was neatly done but lacks some ventilation.
[Image: https://www.dropbox.com/s/zza3nf80m0u9px....jpg?raw=1]

The finish is flaking in a number of areas so there will be some level of cabinet refinish/restoration as well.
[Image: https://www.dropbox.com/s/pyog3awqojl6yu....jpg?raw=1]

[Paul Philco322]

I like those "Saturn" style dial pointers, the inlay on the case is a nice touch. Got some blue caps in the there maybe Aerovox from right here in New Bedford, MA. Good luck.

Paul

[radiorich]

Hello Bob,
Poor little radio I bet was cooking it self to death no vents that is a first that is easy enough to fix thou.
Wow that chassis I count like 9 capacitors not counting the electrolytic .
that looks like a fun little project I have a RCA 1X2 that is about the same size far as the chassis goes .

Sincerely Richard

[klondike98]

Yes it should be fun! I’m also tickled to have found the missing knob on the set. When I got it in the shop it only had one knob and I would have sworn it had both of them when I bought it. I figured it must have fallen off on the way to the car after buying it. But tonight I found it in my living room under a table so it fell off when I first brought it into the house! Lucky me

[Paul Philco322]

Good deal. Before the cats get it .....

Paul

[klondike98]

I have been slowly working away on this radio. I was initially thrown by the unusual power cord arrangement. It looks like there are too many wires. Its not a curtain burner resistance wire (the extra brown wire with the tape on the end) but I think it was part of the antenna loop. The loop or whatever it was part of is long gone so the only antenna now is the external antenna connection.
[Image: https://www.dropbox.com/s/2r4676d9fyz4li....jpg?raw=1]

Some of the other General Television radio schematics do have a power cord antenna system but I could not find a schematic with this tube layout and the power cord antenna. The model 19 and 52 schematic is for the most part correct for the radio although I primarly simply replaced resistors and caps with the values that were in the set already.
[Image: https://www.dropbox.com/s/167p5vnail04cu....jpg?raw=1]

After getting it back together and restringing the tuner it was playing although with extremely low volume. Even my SSTRAN broadcast was barely audible at full volume so I started going through the circuit wire by wire. Lo and behold one of the resistors was 150 ohms but should have been 500k. Swapping that out and it now plays normally

I'll now start working on the cabinet and doing a little more clean up. With a bit closer inspection I now know why that loose knob that went missing in the beginning. The set screw threads in the knob are stripped. I think I have three choices: a) find a new knob, b) drill and tap with a larger set screw or fill the existing hole in the knob (epoxy putty?) and drill and tap with the existing size set screw. Would appreciate any experiences anyone has had trying to fix a stripped set screw thread.

[MrFixr55]

Interesting power cord wiring. Scary thing is, if the GTR 19 Schematic on NA is correct, the chassis u\is hot, not through a cap and resistor, but directly hot. And, of course, the "neutral", not the "hot" is what is switched, so no matter how it 1s plugged in, one stands the danger of getting bit real hard. Likely why someone made that back. My SOP for these radios is to change the wiring so that the switch is on the hot side, the chassis on the neutral side, preferably through a 0.5 uF cap and 250 K Ohm resistor between the chassis and a "Mecca" B- and install a polarized cord.

Is that screw terminal the antenna input or is it a Phono input?

How to fix the stripped thread depends on many factors. What is the size of the current set screw" Go up one size, drill and tap. If it is 8-32, you may be able to drill the hole out and tap for a 10-32. If the knob is deep enough, a 10-32 Allen set screw will work fine, otherwise you will have to cut down from a regular screw and notch the cut end to accept a screwdriver. There is a product called a Helicoil insert for restoring threads. They are commonly used on car engines when a spark plug port is stripped, but I don't think that they make small Helicoil inserts needed for this knob.

[klondike98]

Thanks for the comments. Strange thing is, its not a hot chassis. The "ground" is not the chassis. The common lead for the electrolytics (B- ) is what all the "ground" connections are connected to except for the tube Pin#1 connections. Those Pin 1 connections do go to the chassis so the wiring is not quite what the schematic reads.

The screw is the "external antenna" connection.

The set screw is an 8-32 so my first approach will be to put a slightly longer 8-32 set screw in place and see if there are enough threads still holding to make the knob work. Second approach will be to fill the thread hole with epoxy putty and drill/tap an 8-32 thread. If that fails I'll drill/tap a 10-32 thread.

[David]

I have had good luck using JB Weld and drilling and tapping. Nice radio David

[MrFixr55]

OK, gr8, the schematic is wrong. Guess B- Mecca is connected to chassis via cap and resistor., not shown on the schematic I looked at (Or I hafta stop trying to read schematics at 4:00AM. I always like to go to your other website. Gr8 reading there!!

[klondike98]

Thx David. I will try JB Weld since it’s worked for you.

Thx MrF for the kind words on my website. Yep the schematic is wrong which is why I’ve been unsure what model I’m working on. It’s also clear someone else has been in the chassis before me. That always makes it mor fun!

[GarySP]

Try JB Weld, applying enough to fill the stripped threads but not fully pack the screw cavity. A toothpick works well for this. After it hardens you can re-tap without having to drill out the excess first. Take care and BE HEALTHY! Gary

[klondike98]

Ah…. Thanks! I had not thought of that approach. I was going to fill, drill and tap. This should be easier.

[klondike98]

The grill cloth is intact but I want to take it out so it does not get damaged with lacquer spray and because of the wooden grill I can't really mask it. Originally it was glued directly to the cabinet behind the wooden grill and fortunately the glue is old enough that I was able to pry it off slowly with a knife so I'll be able to reuse it.
[Image: https://www.dropbox.com/s/9l22643wg7umkj....jpg?raw=1]

The cabinet was not in terrible shape. A bit of veneer regluing and a very light strip with citristrip and a light wipe with lacquer thinner on a cloth took off the flaky clear lacquer along with some of the toner lacquer on the top strip of veneer. Hopefully I'll be able to retone that. I did put a coat of lacquer sanding sealer on but will likely wait until I get some warmer weather to try the toner and final clear coats.

[Image: https://www.dropbox.com/s/9s2g8bm32jyclr....jpg?raw=1]