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Im rebuilding an old turntable, I need help!!

crutschow

Well-Known Member
Most Helpful Member
Not sure what that is.
What kind of turntable is this?
Does it have an amp and speaker?
 

N9ne

New Member
I’m not sure as to the the brand of turntable the 2 black wires (top left) is the speaker wire, the brown wires (middle right) go to the bottom of the turntable as for the red and black that’s power
 

audioguru

Well-Known Member
Most Helpful Member
It seems to be an antique record player. The mono amplifier looks like AC127 and AC128 germanium output transistors with clip-on heatsinks. Then the output power is about 0.5W like a cheap clock radio.
 

Ramussons

Active Member
It's a Push Pull Audio amplifier using Transformers.
Yes, as audioguru mentioned, Germanium Transistors, but not a Complimentary transistor Pair combination.

Something on these lines, but stripped down to the bare :D

119960
 

Nigel Goodwin

Super Moderator
Most Helpful Member
Yes, it's just a standard OLD record player amplifier, all transistors will be Germanium PNP as it's transformer coupled (and old).

For the OP, yes it's just a standard volume control, and the circuit will be very similar to post #5, but not using OC series transistors (which were painted glass, not metal). Such amplifiers were EXTREMELY reliable, I don't recall ever having to repair one? - a big advantage of transformer coupled amplifiers.
 

Les Jones

Well-Known Member
You have not asked a question so I will assume you want to know where the wires from the amplifier board go. These are my guesses. The red and black wires at the top right go to the power supply board or if the diode in the top right hand corner is for half wave rectification (Rather than polarity protection.) to the mains transformer. The two black wires from the larger transformer will go to the speaker. The two brown wires from above the volume control will go to the pickup. (NOTE screened cable should be used for this connection. I think this dates back to about 1960 as the design is similar to the output stage of the first transistor radio I bought (Rather than the home made ones I built before that.) when I was about 16.

Les.
 

Nigel Goodwin

Super Moderator
Most Helpful Member
You have not asked a question so I will assume you want to know where the wires from the amplifier board go. These are my guesses. The red and black wires at the top right go to the power supply board or if the diode in the top right hand corner is for half wave rectification (Rather than polarity protection.) to the mains transformer. The two black wires from the larger transformer will go to the speaker. The two brown wires from above the volume control will go to the pickup. (NOTE screened cable should be used for this connection. I think this dates back to about 1960 as the design is similar to the output stage of the first transistor radio I bought (Rather than the home made ones I built before that.) when I was about 16.

Les.
I suspect you're right, and it's just a half wave rectifier - assuming it's not just a battery powered record player?.

There also looks to be an empty space for a tone control, above the input wires - which appears to rather crudely adjust a capacitor directly across the primary of the driver transformer.

Those were the days! :D
 

unclejed613

Well-Known Member
Most Helpful Member
when i was little, i had one of those red and white plastic record players... i would be willing to guess that board or something similar was the guts of it.
 

unclejed613

Well-Known Member
Most Helpful Member

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