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  #1  
Old 08-14-2018, 12:57 PM
Tony F Tony F is offline
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G.E. 810 found

I managed to pick up a G.E. 810 that is mostly in good shape. Cabinet will need re-gluing in places. I tested the 10FP4 picture tube, and it is pretty good for emissions. It must have been a replacement as it is dated 6-60 . Also, it is a G.E. tube. It has a massive 25Hz transformer, that goes nearly to the top of the cabinet. It is missing the GE brass trim button and one inner knob. Also missing the back cover. Here are some pics. Cost me all of $50 cdn. (That's $38.20 U.S.) The seller told me he got it from an auction more than 20 years ago. It has been in storage since. Sellers photos.
Tony
Attached Images
File Type: jpg GE810#1.jpg (59.7 KB, 29 views)
File Type: jpg GE810#2.jpg (71.7 KB, 34 views)
File Type: jpg GE810#3.jpg (71.7 KB, 47 views)
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  #2  
Old 08-14-2018, 01:33 PM
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Phil Nelson Phil Nelson is offline
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Hey, that's a good price! I just started working on the very same (well, US) model. I have only gotten as far as testing the tubes & cleaning it up.

Phil Nelson
Phil's Old Radios
https://antiqueradio.org/index.html
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  #3  
Old 08-14-2018, 02:20 PM
Tony F Tony F is offline
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Here are 2 more photos. The finish loss along the 1 edge (top) needs re-gluing. It must have maybe sat in a basement up against an outside wall to get like that. It looks worse than it is, just finish loss with no problem with the veneer. Also, the metal power (inter-lock) is missing. I ditched the power cord as it was 8' of crumbling rubber and wire. Phenolic antenna connector is also broken. I'll have to straighten the metal part that is wedged under the chassis.
Tony
Attached Images
File Type: jpg G.E.810Back.JPG (50.0 KB, 79 views)
File Type: jpg G.E.810top.JPG (50.1 KB, 42 views)
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  #4  
Old 08-14-2018, 04:48 PM
WISCOJIM WISCOJIM is offline
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Wow, that is a big (and heavy) transformer.

Nice find at a nice price. Congratulations!

.
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  #5  
Old 08-14-2018, 06:39 PM
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Phil Nelson Phil Nelson is offline
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For comparison, here's a view of the power transformer in my US GE 810 . . . much smaller!

I see that you are also missing the metal rear cover for the HV cage. I guess I'll make a new one from sheet aluminum. It appears to be fastened with a single screw at the cage top. Apparently the HV cage has no cover on the other (front) end -- at least, I see no means to attach one.

Phil Nelson
Phil's Old Radios
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Old 08-15-2018, 12:37 PM
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Electronic M Electronic M is offline
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Quote:
Originally Posted by Phil Nelson View Post
For comparison, here's a view of the power transformer in my US GE 810 . . . much smaller!

I see that you are also missing the metal rear cover for the HV cage. I guess I'll make a new one from sheet aluminum. It appears to be fastened with a single screw at the cage top. Apparently the HV cage has no cover on the other (front) end -- at least, I see no means to attach one.

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

It is probably fastened by two screws. My guess is the bottom screw is the one on the back chassis apron under the Horiz Output tube.
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  #7  
Old 08-18-2018, 12:03 PM
Tony F Tony F is offline
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Well I went ahead and pulled the chassis. I removed the picture tube to clean up the chassis. I noticed that the 5Y3 rectifier was missing. The transformer is a replacement. It is a Hammond 28387. There are leads that have been clipped from the 5Y3 tube socket. It has been removed from the circuit entirely. The 5U4G is wired properly. The original (transformer) must have smoked. Any thoughts on why this was done ? There is also a metal can (electrolytic 80 mfd) installed in the "hole" that seems to be "open" on other 810 models I've seen in Bob's videos (where there is none installed).
Tony
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Old 08-18-2018, 02:52 PM
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Radiotronman Radiotronman is offline
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I’ll have to check my ge 810, but I think it’s kind of like the early Motorola sets where the hv back cover is the actual Masonite back of the set.
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Old 08-18-2018, 03:35 PM
Tom9589 Tom9589 is offline
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Interesting schematic. They use a dual selenium rectifier to supply DC to the filament of the mixer/oscillator. The filament winding for the 5Y3 is also used for the CRT. I guess they were concerned about having the CRT filament too close to the ground and filament to cathode shorts. GE did the same thing on its Portacolor set.

I figure the replacement transformer didn't have the two extra taps for the 5Y3, so they installed a dropping resistor between the 390V and 310V sources.
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Old 08-18-2018, 03:43 PM
Tony F Tony F is offline
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Sorry for the confusion. The "hole" I meant is the extra circle "punched" in the chassis just behind the 12AU7. Phil, posted a photo of his set. You can see the G.E. 12AU7 between the transformer and 1 of the electrolytic "cans". Just behind the 12AU7 is the "hole". Seems most sets I see this hole is just "open". In this set there is an added electrolytic "can" cap filling this hole. Maybe I should just go ahead and start the re-cap and keep my eyes out for an "original" 810 transformer.
Tony
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  #11  
Old 08-18-2018, 09:16 PM
old_coot88 old_coot88 is offline
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Quote:
Originally Posted by Tony F View Post
Maybe I should just go ahead and start the re-cap and keep my eyes out for an "original" 810 transformer.
Tony
Are you referring to the 25 cycle power xfmr.? No need to replace it, as it will be quite happy on 60 cycle.
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  #12  
Old 08-19-2018, 08:24 AM
Tony F Tony F is offline
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Yes, I was referring to the power transformer. I know it will be ok on 60 cycle. If I'm going to restore it properly. I'd like to re-install the 5Y3 rectifier to "make the circuit original again". Rather than the way it is. Using dropping resistors, as the transformer is lacking the proper "taps" to drive it. Thanks for the explanation Tom. I'll try to post some photos of the "mods" Besides the transformer is too large for the location . I can't re-install, the metal bracket that is the antenna connection. So if I find an original "Back cover" for the tv it will be in the right spot. The current transformer covers the 2 mounting holes.
Tony
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  #13  
Old 08-20-2018, 10:20 AM
Tom9589 Tom9589 is offline
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Am I correct in remembering that Canada had 25 Hz power near Niagra Falls at one time? Is there something easier about generating 25 Hz than 60 Hz? Lower RPM of generating turbines?
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  #14  
Old 08-20-2018, 11:37 AM
Tony F Tony F is offline
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Tom, I believe you are correct on both points on power generation from the falls.
Here are a few photos of why the transformer is not original to the set. 5Y3 rectifier (wire stubs cut and left). The one phenolyic "standoff" has the same leads just cut and left. One of the electrolyic can caps still has a wire "stub" sticking out from being cut. I also checked the power transformer mounting holes. They appear to be the same dimensions as the original as they were not re-drilled to fit this one. There are a few more bits of evidence of previous repair work. Although, "most" paper capacitors appear original. Also a few resistors appear to have been changed at some point. I spent quite a bit of time cleaning the flyback and area, removing "oily dirty muck" with ammonia on q-tips and following up with naptha. Naptha is also excellent at removing dirt from the flyback itself. It looks like new, however I would NOT recommend using ammonia on the flyback itself, just the surrounding area (insulating phenolyic) and wires. I didn't take any "before" photos. It was completely BLACK with crud.
Tony
Attached Images
File Type: jpg GE 810 bottom.JPG (51.6 KB, 33 views)
File Type: jpg 5Y3 recifier.JPG (52.0 KB, 29 views)
File Type: jpg Previous Repair.JPG (51.6 KB, 28 views)
File Type: jpg Electrolytic Cap Stub.JPG (52.3 KB, 30 views)
File Type: jpg HOT after clean.JPG (52.1 KB, 35 views)
File Type: jpg FlyBack clean.JPG (52.0 KB, 31 views)
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  #15  
Old 08-20-2018, 12:05 PM
Tom9589 Tom9589 is offline
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Wow Tony, I've seen some NOS flybacks that didn't look as good as the one you cleaned up. The wire stubs on the 5Y3 socket have red/green insulation which corresponds to the power transformer taps for the 5Y3 plates. I would be curious as to how the previous repairman dropped the B+ from the 5U4 level to the 5Y3 level. I'm still betting on a big power resistor.
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