Radio Shack PA amp from 1970s

[bachatero]

At my local hardware surplus store there's this clean but old Radio Shack "100w" "PA" amplifier sitting around for a mere $40. I couldn't tell when exactly it was made but it was rack mount with an attached 2 prong power cord (no ground) and in place of the VU meters were these placards saying "Disco Plaza".

Is there any possible purpose to buying this historical artifact or should I just let it sit?

 

[JeffS7444]

Depends on whether you have 70- or 100-volt PA speakers in your home.

 

[sergeauckland]

Check if indeed it has only 70 or 100v outputs. It may also have 4, 8 or 16 ohm outputs. If so, for $40 it would be a very good buy. Could be the basis of a decent valve amplifier.

S

 

[DVDdoug]

Depends on whether you have 70- or 100-volt PA speakers in your home.

That's ONLY if it doesn't have 8-Ohm outputs and that would be unusual.

Constant Voltage setups are normally use in places like supermarkets where there are many distributed speakers. The speakers have transformers with multiple taps so you can select the wattage (and loudness) of the individual speakers.

Most constant voltage amplifiers are mono but you said meters, so it's probably stereo with regular direct-speaker outputs.

Is there any possible purpose to buying this historical artifact or should I just let it sit?

Do YOU have any use for it? Do you know if it works?

and in place of the VU meters were these placards saying "Disco Plaza".

That takes some of the fun out of it.

 

[Speedskater]

Is it Mono or Stereo?
Early 1970's power transistors placed limits on output stage designs.

 

[Timcognito]

Let it sit, most Radio Shack stuff was a low priced second tier commodity. But if you are a @mhardy6647 type guy it might be fun to goof around.

 

[bachatero]

Is it Mono or Stereo?

Stereo

Do YOU have any use for it? Do you know if it works?

I DO know they test everything there, but I already have a 1.6kW Crown amp for whatever needs one. All my speakers are active so the RS one would merely sit around until it has a good purpose.

 

[DVDdoug]

Let it sit, most Radio Shack stuff was a low priced second tier commodity.

A lot of it was simply re-branded and identical to well-known brands except for the badge. I believe they sold re-branded Koss headphones and Shure microphones, and who-knows what else.

...I still have a Radio Shack SPL meter. About a year ago I needed it for something and I wasn't sure if it was still accurate so I bought a calibration gizmo and it was "perfectly" accurate as accurately as I could read the analog meter. (The calibrator was about the same price as another SPL meter but I thought it might be a fun thing to have.)