very nice work purrin! didn't know it could be done like that. also glad to see others enjoy this receiver as much as i do too. do they have the 5000a or 5000x model. i probably sure you know about the f-6013 driver boards and so forth? lucky i found the 5000x since most of them already had the new driver boards installed. picked mine up from local trading post for 60 bucks. now they're selling on avg over 250 on ebay,but i'm never gonna part with mine.

if you need schematics. check out Hifiengine. they have mostly all the schematics you can find. i got my sansui 5000x schematics and manual there.

http://www.hifiengine.com/

just have to sign up before you can download pdf files and so forth, but it's completely free.

well their not made anymore of course(you can still find the parts on ebay though). the 5000,5000a and early 5000x had the bad F-1040 driver boards that were known to opening up and pushing too much current and sometimes catching on fire. i think cause of the square doides were faulty and bad design. the F-6103 boards were newer ones replaced the f-1040. Sansui had major call back for the 5000 series in the 70's. was flagship model but with lots of issues with the driver boards blowing when pushed. it's the 2 boards between the power filter caps. it should say it on there.

Sansui was very popular among Military soldiers overseas. Sansui was specially discounted for soldiers in the military. reason why sansui is still popular a bit in vintage hi-fi. personally i love lot of sansui over more popular marantz and pioneer. also have special thing for kenwood gear. i like yamaha's 80's amps with the M-XX power amps mostly. the 70's yamaha though are very good and were used for their marketing strategy with the term ''orthodynamic'' they used to sell their headphones.

Don't know... They won't be driven hard - just headphones, so maybe the driver boards will last. Funny when Anax saw them: "discrete op-amps". LOL - yeah he is right - huge discrete ones.

As I said, all the major caps need replacement. I just did some minor stuff to get it up and running and performed typical audio-phool modder tricks that typically cost $800-$1500 (cap bypass).

I've just made a headphone -> speaker out adapter to avoid the 680ohm series resistor at the headphone out. It sounds much much better now.

Do you guys get a low-level hum out of the headphone out of these vintage receivers? I've had two (Marantz 2220b and Allied 498), and they both had a hum -- although I've only tried with low-impedance phones. Is there some sort of impedance adapter or something that would get rid of that?

Don't know... They won't be driven hard - just headphones, so maybe the driver boards will last. Funny when Anax saw them: "discrete op-amps". LOL - yeah he is right - huge discrete ones.

As I said, all the major caps need replacement. I just did some minor stuff to get it up and running and performed typical audio-phool modder tricks that typically cost $800-$1500 (cap bypass).

I've just made a headphone -> speaker out adapter to avoid the 680ohm series resistor at the headphone out. It sounds much much better now.

yea i don't know why but speaker outputs make some headphones just sound better(well to me). i believe studios back then use to do that as well hooking up lot of headphones directly to the speaker outputs. i knew they made adapters then before the headphone jack on amps came out to run headphones off tube amps. problem though is tubes are always transformer coupled so had to match the impedance with resistors. always downside to tubes is they have a set output impedance from their power transformers.