RCA RS164A mono tube amp socket ID

Tia

Did you say birds?
Newbie here trying to power this thing up. I think something needs to go in this socket. Any help would be much appreciated. Bob
l1.JPG l2.JPG
 
I think that is for the indicator lamps. See if you get 6.3 VAC between the outer two pins.
If you haven't yet fired up the amp, take the tubes out when you first try it.
 
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OR
It could be for AC power to the record player motor, with a lead coming back after the switch. In which case it would have 120VAC on two of the three pins.
I think this answer is better than my previous, but a voltmeter will tell all.

Since there is no on/off switch on these chassis, I think it is turning the record changer on that turns the amp on, and subsequently, off.
 
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It looks like the power cord in the bottom of the pic of your innards goes to that plug, so it might be a power take off for the phono. Don't see any fuses or even a safety cap. RWood might be correct too though.

Edit

I see RWood posted while I was pondering
 
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Power connection to the Record player. Fisher and RCA liked using these in the 50's. Rca into the 60's. The schematic is in the 1958 Beitman's manual, Page 141. RCA RS-164.jpg

RWOOD Beat me but I had to look up the scat! It's the Power for the Phono.
 
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Awesome job guys. Next up- I see audio in but don't see anything for audio out (speakers)..............
 
yes indeed, but Larry come in with da PROOF!

Last year I turned one of those into a Fender Harvard circuit. I did repurpose that power jack to feed the lamp indicators that I put behind the knobs. The trannies in this amp are perfect for a Harvard. Great Steve Cropper tone.

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Next up- I see audio in but don't see anything for audio out (speakers)..............

Below the ORANGE capacitor in your gut shot there are three wires coming in which is the OT secondary. Follow those; they should go to a terminal strip. Green is 8 ohms and black is ground.
 
Below the ORANGE capacitor in your gut shot there are three wires coming in which is the OT secondary. Follow those; they should go to a terminal strip. Green is 8 ohms and black is ground.
The terminal strip is nowhere to be found. This might end up in the hands of someone more capable of putting it to use.
 
Maybe not - take a pic of the back side of the output transformer - the smaller trannie mounted up top.
 
If you're not sure about the electronics aspect of this thing, I wouldn't mess around with it. Tube amps have lethal voltages so unless you know what you are doing, let someone else work on it.

The bigger black transformer is the main power transformer. The smaller one with the brown paper wrap is the speaker output transformer. It only has two wires that connect to the speaker(s). Yellow & black. Solid state stuff does not use or have speaker (output) transformers with the exceptions of some solid state PA amplifiers.

The one side with the black & yellow wires is what's known as the secondary side of the transformer. The other side (wire colors unknown) are what's known as the primary side and these wires connect to the output tubes which are the 6V6GT's.

If you look at the picture Larry posted in post #5, it shows everything that yours has even the speaker connections..........and yup, yours does too!
 
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If you're not sure about the electronics aspect of this thing, I wouldn't mess around with it. Tube amps have lethal voltages so unless you know what you are doing, let someone else work on it.
The utmost care and safety will be used when learning my new hobby, I have manage to remain unscathed from a previous hobby of drag racing motorcycles, and my current hobby of shooting competitions with fully automatic weapons ;)

The bigger black transformer is the main power transformer. The smaller one with the brown paper wrap is the speaker output transformer. It only has two wires that connect to the speaker(s). Yellow & black. Solid state stuff does not use or have speaker (output) transformers with the exceptions of some solid state PA amplifiers.

The one side with the black & yellow wires is what's known as the secondary side of the transformer. The other side (wire colors unknown) are what's known as the primary side and these wires connect to the output tubes which are the 6V6GT's.

If you look at the picture Larry posted in post #5, it shows everything that yours has even the speaker connections..........and yup, yours does too!
cademan thanks for taking the time to explain this, I really appreciate it.

Will do a test and report back
Cheers!
Bob
 
Bob I am curious now as to what your plan is for this amp and what steps you are going to take in getting it turned on.

As it stands, it only needs an on/off switch jumpered in to the circuit to turn it on, but the amp has no protection to prevent the chassis from going live if it is shorted out. Perhaps the original turntable has a safety cap installed that will provide some degree of protection, if it has not failed from age.
You probably know that you must connect a speaker before you turn it on or you risk damage to the transformer
Some of those caps are looking very iffy and all of them should probably be replaced
Have you made a dim bulb current limiter
 
It's not a series string hot chassis so its not going to have any live mains on the chassis if something were to short out. The power transformer acts like an isolation transformer.

You don't really need to connect the speaker when powering up. Just don't have any input or have the volume turned up and it will be fine for the first few minutes of testing.

In my 40+ some years of doing this, I have never seen, heard, or tested a console tube amp that ever went into oscillations without the speaker connected. Might happen with more exotic more expensive tube amps, but not these cheaply built mass produced console amplifiers.
 
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It's not a series string hot chassis so its not going to have any live mains on the chassis if something were to short out. The power transformer acts like an isolation transformer.

You don't really need to connect the speaker when powering up. Just don't have any input or have the volume turned up and it will be fine for the first few minutes of testing.

In my 40+ some years of doing this, I have never seen, heard, or tested a console tube amp that ever went into oscillations without the speaker connected. Might happen with more exotic more expensive tube amps, but not these cheaply built mass produced console amplifiers.
Thanks for the clarification cademan.
 
Below the ORANGE capacitor in your gut shot there are three wires coming in which is the OT secondary. Follow those; they should go to a terminal strip. Green is 8 ohms and black is ground.
If green is 8ohms output and black is ground what is yellow? Another output? If so how many ohms?
 
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