PL4000 rebuild

[marcok]

-I fited the relay with adhesive strips by Pattex , since I didn't find an other solution .
- Don't forget an anti sparkling cap 630 V ( 10000 pF for 120V and 22000 pF for 230 V )
-I fitted vertical caps ; no problem with clearance .
-500 W drill and polish paste by Dremel for knobs .
-Use a bench vise and 6mm ( 1/4" ) dril bit to lock the knobs .
-Use a polish disc for alu
Done for one unit. ( 6 pieces )
Ciao
Marco

 

[Overundr1]

Having priced out the axial caps finding out that the radials will work is a big $$$ saver ty sir.

 

[Overundr1]

Board sealed, new rca jacks ordered and mounts all cleaned of flux. Would not attempt this step without a desoldering station.
By the way this is one of the first with a sub 1000 serial number.

 

[Overundr1]

Moving right along. New caps, transistors checked and molex

 

[Vynuladikt]

Is that an Eight hiding behind the DigiKey bags? And now under the boards.

 

[Overundr1]

Fully restored 7000 sir. Boards are sitting on top of the qr-4500 quad

 

[Overundr1]

Getting closer, one board to go. The caps are strong in this one Obewan

 

[J!m]

Still like the look of that Sansui gear...

 

[Overundr1]

 

[Overundr1]

Forgot to say thank you for the acrylic nail polish on pin side connector trick. Really takes the joint flex out of the solder point trace connection. I also want to clarify my comment about parts list. Instead of a sheet at the end of the manual aka how Sansui does things the designers have every part identified on the actual schematics which is quite helpful.
Am a little worried the young lady at the local Dollar General not going to 'buy' my reason for buying more nail polish though; there cannot be that many senior citizen male shoppers swarming the store for this particular product

 

[Overundr1]

Ok, one more Sansui picture just to show off a bit.
QRX-9001 basket case after full on restoration, pinned boards, custom driver cards, custom auxiliary quad board power supply, upgraded main caps etc etc etc. Inside shot while testing and measuring. So much to learn about Phase Linear before I even begin to come close to achieving the same results on this iconic gear.

 

[marcok]

When the switch on ?
Ciao
Marco

 

[marcok]

A last minute idea :
Short the two legs of the relay if conctacs are in a decent state .
I could not do , because my relays were destroyed .
Ciao
Marco

 

[Vynuladikt]

Ok, one more Sansui picture just to show off a bit.
QRX-9001 basket case after full on restoration, pinned boards, custom driver cards, custom auxiliary quad board power supply, upgraded main caps etc etc etc. Inside shot while testing and measuring. So much to learn about Phase Linear before I even begin to come close to achieving the same results on this iconic gear.

I have one on the shelf waiting for my retirement so I can do it justice. I also have an Eight as well as a few other Sansui prizes waiting.

 

[Overundr1]

While waiting on the rca jacks thought I would start on the cosmetics. Faceplate certainly is respectable after fifty years.

 

[Overundr1]

Knobs and top cover done. All boards done, waiting on rca jacks and then re assembly will begin.

 

[Overundr1]

One quick question. Noticed this red wire was loose, cannot figure out where it attaches? Schematic shows it wandering off without showing the other end.

 

[Overundr1]

When I took things apart here is where the wire was taped off to?

 

[marcok]

The led of peak unlimiter threshold is connected to pin 8 of peak unlimiter board and B+ through a 22k resistor.
Ciao
Marco

 

[Overundr1]