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  #31  
Old 08-21-2015, 09:53 PM
Captainclock Captainclock is offline
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Well I got the record player going finally, and was able to figure out why it had a hum to it, it was because the connector from the turntable to the amp lost its ground connection (the ground wire was completely missing from the RCA Plug all that was left on the plug was the solder) so I took and replaced the old cable with a new one I had laying around and the hum went away.

The only thing I can't figure out is how the tone control is supposed to work, because for some reason or another the tone control knob instead of it making the record player's audio sound more bass or treble sounding it raises and lowers the volume like a volume control knob does (even though it already has a volume control knob) any ideas as to what would be causing that?
The only thing I can think of that could be causing the tone control some issues is that it has 2 .0022 MFD 400 Volt paper caps attached to the control and that maybe those capacitors are causing the tone control knob some issues because of them being "leaky" but not sure.

Interestingly enough the record changer mechanism still works perfectly as found without any need to overhaul the unit, which is kind of interesting seeing as this record player was obviously stored in a shed or a barn part of its life...

Last edited by Captainclock; 08-21-2015 at 10:54 PM.
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  #32  
Old 08-22-2015, 10:03 AM
dieseljeep dieseljeep is offline
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Quote:
Originally Posted by Captainclock View Post
Well I got the record player going finally, and was able to figure out why it had a hum to it, it was because the connector from the turntable to the amp lost its ground connection (the ground wire was completely missing from the RCA Plug all that was left on the plug was the solder) so I took and replaced the old cable with a new one I had laying around and the hum went away.

The only thing I can't figure out is how the tone control is supposed to work, because for some reason or another the tone control knob instead of it making the record player's audio sound more bass or treble sounding it raises and lowers the volume like a volume control knob does (even though it already has a volume control knob) any ideas as to what would be causing that?
The only thing I can think of that could be causing the tone control some issues is that it has 2 .0022 MFD 400 Volt paper caps attached to the control and that maybe those capacitors are causing the tone control knob some issues because of them being "leaky" but not sure.

Interestingly enough the record changer mechanism still works perfectly as found without any need to overhaul the unit, which is kind of interesting seeing as this record player was obviously stored in a shed or a barn part of its life...
That is a strange approach to a tone control circuit. I has a ganged pot with a common shaft to turn both pots. I looked at the schematic you have and it's clear enough, other wise, I could send you the Sams. It's only one page, printed on both sides.
Use contact cleaner on all the pots and replace the tone compensating caps.
Make sure the return to ground on the control sub-chassis is solid.
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  #33  
Old 08-22-2015, 05:37 PM
Captainclock Captainclock is offline
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Originally Posted by dieseljeep View Post
That is a strange approach to a tone control circuit. I has a ganged pot with a common shaft to turn both pots. I looked at the schematic you have and it's clear enough, other wise, I could send you the Sams. It's only one page, printed on both sides.
Use contact cleaner on all the pots and replace the tone compensating caps.
Make sure the return to ground on the control sub-chassis is solid.
Well actually I returned the unit to the gentleman today and even with it working as was he was tickled pink that the record player changer still worked without me having to overhaul it and that all I had to do to fix it was clean the 12AX7 tube socket and replace the cable for the record player. and then replace the old 12AX7 which was gassed(it was cracked all the way around which broke the vacuum in the tube.) I was actually out of contact cleaner so that's why I wasn't able to clean the controls properly and I didn't have any money to get any. He didn't seem to care that the tone control knob wasn't working 100%, although I did get something pretty cool today when I took the record player back to the gentleman I worked on the record player for, I got an old tube powered phono preamp unit and an old RCA Intercom unit and an old Westclox Baby Ben alarm clock.
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