Philco did similar on some of their 50's split-chassis sets...Only the permanent magnet was enclosed in a fixed mounting bracket which contained a screw mechanism to move the magnet that had a flexible adjuster shaft that stuck out the back...You're right GE was comparatively cheezy on their system.

Okay, we're not as close to done as I thought. Cleaning the tuner a second time eliminated most of the crashing. In the course of doing more systematic voltage checks, I found two burned resistors on pins 6 and 7 of V4, the 6AU6 2nd video IF amp. (How did I not see those before?!?)

https://antiqueradio.org/art/GE810Te...dResistors.jpg

That's good, but I still heard a little crackling when warming up. Just for kicks, I powered up in total darkness and, during the initial surge, noticed a wee twinkle on the socket of V17, the 6AU6 2nd audio IF amp. When I scraped & probed that area with a dental pick, I discovered that the socket had arced and burned holes in two spots: between pins 5-6 and pins 6-7:

https://antiqueradio.org/art/GE810Te...rnedSocket.jpg

Gack. I dug out the burned holes as best I could with the pick, and powered up again. thinking I could fill the holes with epoxy if my surgery had removed all the carbonized material and there was no arcing across the air gap. This time, the arcing was brighter, so that socket's too far gone to save with a quick fix.

That'll be the end of voltage checks until I order a new 7-pin socket and install it. Meanwhile, I'll take a closer look at other resistors & sockets. Perhaps it's not a coincidence that I found Bad Things on pins 6-7 of two separate 6AU6 tubes employed as IF amps (or maybe GE just used cheap sockets).

Phil Nelson

The tube sockets that arced like that were generally damaged by a liquid that was spilled on the chassis. How???

The area around that socket doesn't look like it was doused with mouse pee. It's hard to imagine any other way to get that socket really wet. The chassis as found was quite dusty, but with no serious rust or signs of moisture damage.

The socket phenolic looks somewhat burned from the top.

https://antiqueradio.org/art/GE810Te...-PinSocket.jpg

This socket's chassis opening is larger than needed for a 7-pin tube. The chassis hole is 1" in diameter and the mounting centers are 1-5/16". It's as if the chassis previously had a standard octal tube in that position and they changed to a 7-pin tube and got wafer sockets to fit the same hole.

I've been looking at the usual sources (Surplus Sales of Nebraska, eBay, Antique Electronic Supply), and nobody seems to have a 7-pin socket that fits.

Does anybody know of another source?

Phil Nelson

If no one knows of a good source for those sockets one option would be to get some phenolic or brown plastic and make an adapter wafer to go between a standard 7-pin socket and the chassis holes.

Thanks. A fellow collector just offered to send me one, so if that works, I shouldn't need to fabricate.

Phil Nelson

You can install a octal socket in it's place & use a 6SH7.
I believe that it is comparable to a 6AU6. it would also make it appear more original.

In regards to the cheap sockets that G.E. used, this was a typical problem with them.

For future reference, Angela Instruments has adapter plates. Far from stock look, but a possibility.
https://www.angela.com/sevenpintubes...ccesories.aspx

OK, I replaced the arcing socket and the five components mounted on it.

https://antiqueradio.org/art/GE810Te...ngSocket03.jpg


https://antiqueradio.org/art/GE810Te...ngSocket05.jpg

https://antiqueradio.org/art/GE810Te...ngSocket07.jpg

Now the audio quality is nice -- at least as good as before. I still hear occasional crashing and static, however, so I'll have to investigate further.

In similar cases with my Admiral 24A12 and 24C15 consoles, I had to replace the uninsulated mica capacitors inside the audio IF cans. Does anyone know whether the 810 has that type of naked mica inside these cans?

Regards,

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

Phil, changing that socket was surely a PITA. But in the end, it was the only right thing to do. And, you used the same type of socket. I had to replace three tube sockets in my Heathkit TT-1A and that was quite a challenge. A challenge to first find the oddball sockets and then work around all of those wires. But now, it works just fine.

Good job!