No Amplification from SX-1080

[Seabody]

Hey folks,

I'll start this off by saying that I'm an absolute vintage newbie. I have my father in law's old SX-1080 which seemingly is in great working order - powers on without issue, no lights missing, all switches working without noise etc.

I tried hooking it up last night to a pair of passive speakers and simply couldn't get any amplification. I tried multiple sources (turntable, FM, AM) and on AM I could faintly hear sound through the speakers with my ear up to them. When I switch the speakers off on the console I can hear it engage/disengage with the standard audible crackle. I've tried both left and right, A & B channels, played with all the different controls (tape deck off, muting off, loudness on, and every combination of other options I could think of).

I had the unit working once before using the headphone jack lined to a small portable Bose speaker to play radio. I'm guessing that this setup worked because the Bose was providing the amplification.

Any thoughts on next steps here? I'e included some pics and there is some rust showing from the top grill. I'm a little intimidated to perform surgery here due to the aforementioned newbieness. Any guidance on if this is salvageable would be appreciated.

Tried to provide as much info as possible here, but let me know if I've left out anything critical.

Thanks in advance,

Seabody

 

[sruchris]

What do you hear if you plug in a pair of headphones? Do you hear a click 5-10 seconds after you turn the stereo on?

 

[Seabody]

Hey there,

Faint sound through headphones if I max the volume, but barely audible. Yes there is a click 5-10 seconds after power on.

Thanks,

- Seabody

 

[sruchris]

If you connect a source into Tape Monitor 1 or 2, and switch those on, do you get sound? Cleaning the tape monitor switches would be a good first step.

 

[llwhtt]

Pre amp/power amp jumpers installed in back of the unit?

 

[opnly bafld]

It looks like the 3 "Tape" switches should all be in the up position.

 

[markthefixer]

You NEED to download the service manual for the unit - which will explain the various switches and plugs.

READ IT!!!!

https://www.hifiengine.com/manual_library/pioneer/sx-1080.shtml

Make sure there are pre-power jumpers in the set of receptacles about dead center of the BACK of the unit.
Although the SAME symptoms will be realized with the "TAPE" switches out of place - like your picture suggests.

 

[Seabody]

Hey all,

Thanks for the replies!

@sruchris - Nothing at all when hooked into the take jacks. I tried both as well as the aux input for good measure. @openly bafld - I've tried the Tape switches in all different configurations with no luck. :/

@llwhtt - there are jumpers on the back as far as I can tell. Pic included for reference. Could this be my problem?

 

[opnly bafld]

Pre out and main in need jumpers or rca interconnects if you don't have jumpers.

 

[llwhtt]

There are NO jumpers installed between the preamp and the power amp, that's your problem.

 

[Seabody]

Got it! Pre-power jumpers were missing as you said - tried an RCA cable between the two and it now works like a charm!

Thanks for the help all! Glad this was something simple and I was just being a newb!

 

[whoaru99]

Might have had an equalizer or something else connected there as why the jumpers are missing.