Low volume Symphonic record player

3/9/2011 7:07:08 PMDoug Prowse

I need some help with a Symphonic RMA 351 portable 120 volt record player by Radio And Electronics Corporation Boston, Massachusetts. I believe this is probably from the twenties and thirties but I can't find anything about it on the Internet including systematics. It has very low volume but other than that it works fine. I have checked the three tubes 37Z5, 50L6GT and 12SQ7GT and all are good. I have replaced both the electrolyte along with the rest of the capacitors. I am very new at repairing these old electronics and could use any help I can get.
Thanks for your time, Doug

3/9/2011 8:07:07 PMEdd

Sir Doug. . . . .

Methinks that . . . assuredly time has taken its toll on the cartridge in the tone arm of the record player portion.
Note that with that given tube lineup you are more in the 40's vintage.

If touching a metal screwdriver blade with a moistened finger and the blade in turn touching the UNSHIELDED wire of the pair going to the cartridge, should give you a healthy . .HUMMMMMMMM.... from residual AC powerline signal being picked up by your body .

That . . . considering that you are NOT prematurely grounding that weak signal out by touching the tonearm in case it is metal . . . hopefully its plastic.

If the sound level presently produced by the existing cartridge is just borderline in volume level ?

You might look into pulling the 12SQ7 qnd putting in a 12SK7 and adding a resistor or two and then have yourself a much higher gain pentode stage instead of the use of existing triode design of the 12SQ7.

Ask for more details if you no fathom . . . .

73's de Edd

:I need some help with a Symphonic RMA 351 portable 120 volt record player by Radio And Electronics Corporation Boston, Massachusetts. I believe this is probably from the twenties and thirties but I can't find anything about it on the Internet including systematics. It has very low volume but other than that it works fine. I have checked the three tubes 37Z5, 50L6GT and 12SQ7GT and all are good. I have replaced both the electrolyte along with the rest of the capacitors. I am very new at repairing these old electronics and could use any help I can get.
:Thanks for your time, Doug
:

3/10/2011 7:20:10 AMDoug Prowse

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:Sir Doug. . . . .
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:Methinks that . . . assuredly time has taken its toll on the cartridge in the tone arm of the record player portion.
:Note that with that given tube lineup you are more in the 40's vintage.
:
:
:If touching a metal screwdriver blade with a moistened finger and the blade in turn touching the UNSHIELDED wire of the pair going to the cartridge, should give you a healthy . .HUMMMMMMMM.... from residual AC powerline signal being picked up by your body .
:
:
:That . . . considering that you are NOT prematurely grounding that weak signal out by touching the tonearm in case it is metal . . . hopefully its plastic.
:
:
:If the sound level presently produced by the existing cartridge is just borderline in volume level ?
:
:
:You might look into pulling the 12SQ7 qnd putting in a 12SK7 and adding a resistor or two and then have yourself a much higher gain pentode stage instead of the use of existing triode design of the 12SQ7.
:
:
:Ask for more details if you no fathom . . . .
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:73's de Edd
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::I need some help with a Symphonic RMA 351 portable 120 volt record player by Radio And Electronics Corporation Boston, Massachusetts. I believe this is probably from the twenties and thirties but I can't find anything about it on the Internet including systematics. It has very low volume but other than that it works fine. I have checked the three tubes 37Z5, 50L6GT and 12SQ7GT and all are good. I have replaced both the electrolyte along with the rest of the capacitors. I am very new at repairing these old electronics and could use any help I can get.
::Thanks for your time, Doug
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I want to thank you for taking the time to reply and so quickly. You are correct it is a bad cartridge. I learn something new which is a good thing, I guess for an old geezer :-).
Thanks again, Doug

3/9/2011 8:12:46 PMWarren

Your phono is from the late 40's Early 50's. It probably needs the cartridge replaced. You should get a loud buzz if you touch one of the wires going to the cartridge with the volume turned up.

3/10/2011 7:19:06 AMDoug Prowse

:Your phono is from the late 40's Early 50's. It probably needs the cartridge replaced. You should get a loud buzz if you touch one of the wires going to the cartridge with the volume turned up.
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I want to thank you for taking the time to reply and so quickly. You are correct it is a bad cartridge. I learn something new which is a good thing, I guess for an old geezer :-).
Thanks again, Doug

3/10/2011 5:36:57 PMwant to restore it?

Hello Doug... If you want to restore the old cartridge you can send the cartridge to west tech services..they specialize in rebuilding old phono cartridges...its not cheap ..around $40.00 but if it is something you cherrish it is well worth it.