Restoration time!
So, I've got one! Great condition - perhaps an 8.5/10 - before any restoration.
First thing I did was clean it! Gosh it was dusty both outside and especially inside! I used a small paintbrush to loosen the dust and a small hand vacuum to remove the dust safely. Being ever so careful not to dislodge anything or disturb any componenets I brush away and vacuum'd for about 20 minutes on/off.
At least now the dust won't start a fire or cause a short circuit blow out.
This led to visable confirmation of some sort of residue covering almost all the circuit boards. Probably airbourne particles over many years settling inside. I wasn't in any way going to attemt to wipe this off. It would be left to my Audio Engineer to deep clean once disassembled.
So far so good. Everything visably seemed to be solid and OK. I'm no electronics expert so testing componenets and evaluating them for faults or efficiency was way out of my abilities.
I hooked up my speakers, attached my CD player and turned it on. Unit powers up nicely and the Soft Start system does its job. We have power and are ready to feed a signal!
CD inserted - Gotan Project - as I know the music and sounds quite well - it started. All I can say is that it sounded totally different. In a very good way. Solid and slightly warm overall. Very nice. I turned it up. Quite a bit... oh wow! Now we're talking. The sounds slightly change to a rock solid presentation. Separation is extremely good and bass /treble are better than I knew before. This unit has got some guts inside!!

Nevertheless, I still had to get this unit checked over then restored regardless of its current performance.
As it was a pretty straight and genuine example, which has had little work carried out on it within its 40 year existence, I was nervous of something inside letting go or blowing on me. The Tuner issue was the start of my concerns as when one thing goes it normally follows through the system in a concertina effect.

This is a monster unit stuffed full to the brim with circuit boards and electronics! Luckily, with the way the interior is arranged, almost modular, these are fairly easy to access & remove.
By an experienced Audio Engineer of course!

A couple of weeks later the SX-1980 is off for its full check up and restoration. I've used it lightly for those weeks being careful not to overwork it to 'explosion point'. So far, so good.

I'm taking this 36Kg beast by car to my Audio Engineer who lives about 270 miles away!
This calls for an overnight stay at a Premier Inn I do believe!
All you can eat Breakfast!

The Restoration Process begins!