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Tell me what this is

I picked up long ago in a yard sale. Seemed interesting enough for an audio guy but Ive been looking and haven't found anything on it yet. I still have the original knobs I was just seeing how the newer style would look.:eek:

Pioneer Hifi is all I got here. What is it? Its an amp but for what ? Can anyone direct me to definitive info on this unit?
 

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The only one on top is a 40 + 40 MFD 500WV Nippon Chem-con

That's quite consistent with it being branded Pioneer.

I see 2X large, metal envelope, tubes, which are probably 6L6s. Definitely provide us with the full tube complement.

The I/P connector appears to be a phone, as opposed to RCA, female.

A mono HIFI amp is my guess.
 
Hi Eli, I don't know much about this but it even has 2 more sockets across the back beside a power plug .But yes 2 CRC 6L6's are present. A RCA Jan 5v4-G vt-206-A ,Admiral 322852 , NEC 24 S6N7..... faded on the glass, JAN-CNU 6SG7GT, Den onkon CH-2420. A summing output transformer and the other I cant read.

Hugh
 

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A photo of the back side might help.

If only 2 wires come out of the CH-2420, it's a choke (inductor).

A 6SG7, being remote cutoff (non-linear), is not the sort of thing you expect to find in HIFI circuitry. Please check that bottle again, carefully.

40 μF. is a bit big to use as the 1st cap., with a 5V4. Look at the underside for another, smaller value, 'lytic near the rectifier's socket.
 
Looks like a PA amp of some kind,,, would certainly make a cool guitar amp!
I was leaning that way but I couldn't find one as an identical match. It actually has two 1/4 inch phono plugs on one end and a singular on the other. If it works and plays some audio just because it looks cool why not run it. I was just wondering about its sonic quality and value more or less.
 
How about interior shots?

The jacks on the end panels strike me as odd. My first impression was they might have been added by someone.

The octal socket on the rear suggests this power amp had a companion preamp that ran through an umbilical cord.

Only one of those rear sockets go to anything. It goes appears to be wired to the output transformer. Model H 30-8
 

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The OP stated 5V4, but you are correct about the 5U4. It's certainly easy enough to mix "U" and "V" up. A construction expert (I'm not) would quickly discriminate between a directly heated type (5U4) and a type with cathode sleeves (5V4).

Definitely a 5V4G, as shown in post #7, but also shown by having flat plates rather than folded type like the 5U4G.
Methinks the 5V4G would be a bit stressed in this circuit.

A very classy amp in its day, I'm sure. Bet the OP would LOVE to find a companion to it.
Sansui == Tango OPT == mmmmmmmmmmmmmm!
 
How about interior shots?

The jacks on the end panels strike me as odd. My first impression was they might have been added by someone.

The octal socket on the rear suggests this power amp had a companion preamp that ran through an umbilical cord.

The amp definitely has been modified, but early amps did have 1/4" jacks for a microphone.
The octal socket is not connected to anything internally.