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Philco 46-1201 Restoration
#46

Is the tuning cap mounted on rubber grommets? If so your coil pin 4 is attached to B- not ground.

Gregb
#47

I will double check.. But I think the Tuning cap was at ground..

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#48

Ok, Tuning Cap is at ground. According to schematic it should be..

I believe the Rubber grommets are probably for vibration??

[Image: http://i292.photobucket.com/albums/mm38/...7xisla.jpg]

[Image: http://i292.photobucket.com/albums/mm38/...kalfh1.jpg]

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#49

All, While I was waiting on parts for my RCA V-210. I decided to look at my 46-1201 again. Since it was to much to ship out and nobody wanted it around here..

I was determined to get it working... So I started to rewire the front end according to the schematic.. It wasn't even close to what it should be.. Figured that would do it. However when I turned it on again it would motorboat especially at the top of the band..

So I tried alignment but the motor-boating was so bad it would wipe out the signal.. It did pick up a lot more stations.. The alignment instructions were not that great either..

So back to the drawing board.. More to follow...


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#50

Ok, Continuing: I went in and checked all connections again. I could not find anything wrong.. But something was causing the motor-boating.. So since I had ordered replacement tubes for this I decided to start substituting tubes one by one.. I stared with the first tube a 7A8 converter tube..

[Image: http://i292.photobucket.com/albums/mm38/...foiu1k.jpg]

Replaced with my second spare ( I always try to order 2 tubes just in-case) Glad I did that because when I replaced it the Radio started to play with NO motor-boating . Picked up all stations load and clear.

So I did a realignment and all peaked good. Now radio is playing great...

Question is:: What could have caused the tube to cause the motor-boating ? I checked the tube on tester and it tested fine.. Goes to show you that even if tube tester shows a tube good It may not work in all circuits...

Anyway now on to the phone section>>> Wish me good luck with that..

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#51

Ok, Now sense the radio is working it was time to move on to the phonograph.. Hooked it up and put in record. closed door and it started to play didn't sound to bad. However the volume was low compared to the radio side...


So I will have to find out why next week.... But off to a Radio Conference for the weekend for MARS
( Military Auxiliary Radio system)

more to follow:...

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#52

Nice work Icon_thumbup Icon_thumbup Icon_thumbup
#53

Well back from weekend. I found a 56K resistor across the phono cartridge that wasn't on schematic. So I removed it and now the phono side volume is as good as the Radio side.. Why someone would do that who knows...

So records now play good. I will still go into it and clean,lube ETC .. Maybe paint? This was the biggest challenge so far... And I thought that the other console I did a 42-1012 and replacing the rubber wire was bad.. Piece of cake compared to this..

So now have 3 working out of the 6 I got recently. The 6 I purchased were a Philco 46-1201,46-1203,46-350 and RCA T55, and V210 with a Stromberg Carlson 440M..

Working so far are the Stromberg, RCA T55 and the 46-1201.. Working on the V210 now,capacitor replacement..

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#54

(10-02-2016, 07:59 PM)vecher Wrote:  Well back from weekend. I found a 56K resistor across the phono cartridge that wasn't on schematic. So I removed it and now the phono side volume is as good as the Radio side.. Why someone would do that who knows...

So records now play good. I will still go into it and clean,lube ETC .. Maybe paint? This was the biggest challenge so far... And I thought that the other console I did a 42-1012 and replacing the rubber wire was bad..  Piece of cake compared to this..

So now have 3 working out of the 6 I got recently.  The 6 I purchased were a Philco 46-1201,46-1203,46-350  and RCA T55, and V210  with a Stromberg Carlson 440M..

Working so far are the Stromberg, RCA T55 and the 46-1201.. Working on the V210 now,capacitor  replacement..

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 The resistor in question was probably added at the factory to tamp down the output of the original Rochelle Salt crystal cartridge which would have been about 3 volts, it probably died, or wore out, and was replaced with a newer ceramic one which puts about maybe 1 volt if you are lucky. The orginal one in my Bing Crosby is dead so it will likely be replaced by a more modern ceramic element cartridge, I could rebuild the original but since it can't be seen there isn't much point.
Regards
Arran
#55

Thanks, So I do not really need it? It seems to work great as is. I will not damage cartridge if I do not use it .. Will I ?

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#56

(10-03-2016, 10:00 AM)vecher Wrote:  Thanks,  So I do not really need it? It seems to work great as is. I will not damage cartridge if I do not use it .. Will I ?

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 No it won't damage the cartridge, the intent was mostly to prevent the signal from the crystal cartridge from overloading the grid of the 7C6 tube, if it is not distorting then it clearly is not overloading the grid.
Regards
Arran
#57

Arran, Ok thanks.. That makes perfect sense..

I wonder why it was there ? Since it sounds good and much loader without it..

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