Author Topic: Quad 303 restoration  (Read 35252 times)

Offline mygoggie

Quad 303 restoration
« on: December 31, 2018, 10:02:19 AM »
INSERT:

Content:
This is a new post inserted to list all of you who have donated towards the project.

Any project can either be tackled alone or people can start owning part of it by contributing. I simply love it when others find a project interesting and want to contribute in some form or way.

I asked @Family_Dog to edit this post so that I can acknowledge those of you who are contributing. Without you I cannot complete the project. Thank you and I salute you!

@Nchebe - redesign of the regulator and output PCBs into Gerber format.
@Family_Dog - supply of the Saf Dem cleaning and anti-corrosion fluid and his patience for helping me start this thread.
@JohnnyIC - supply of a variac
Rob of Pollocks - UV printing of plates

and then lastly, to all of you who have commented, offered advice and compliments in the various posts below, keep posting!

---

Quad 303 restoration

I found this Quad 303 and this Quad 33 abandoned when my neighbour moved out.

Maybe I am crazy, but I think I will give the restoration a go.

It looks better on the photos than in real life. Quite bad corrosion on anything that is metal.



















« Last Edit: July 25, 2019, 02:42:10 PM by Family_Dog »
Herman

~ To heal the soul is to embark on a new journey. ~

Offline marantz123

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Re: Quad 303 restoration
« Reply #1 on: December 31, 2018, 10:33:11 AM »
Is this the same one that you posted about regarding the BC transistors needed, or is this another find ? Good luck with the restore...results should be pleasurable!

Offline mygoggie

Re: Quad 303 restoration
« Reply #2 on: December 31, 2018, 10:36:42 AM »
Is this the same one that you posted about regarding the BC transistors needed, or is this another find ? Good luck with the restore...results should be pleasurable!

Jip, the same one ... just had time to find the parts first and now the work starts.
Herman

~ To heal the soul is to embark on a new journey. ~

Offline marantz123

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Re: Quad 303 restoration
« Reply #3 on: December 31, 2018, 10:50:14 AM »
Pull those to5's and to66's and test the hfe, diode test, and junction resistances as well. Check diodes as well ( junction resistance and diode test). No point putting in new power transistors ( if needed) without making sure the driver/input stages are good. Those 40352 RCA to66's might be hard to find but can replace with TO220 packages. To5's are still available most places.

Offline Family_Dog

Re: Quad 303 restoration
« Reply #4 on: December 31, 2018, 11:23:15 AM »
Looks to be an interesting project, the PCBs look fairly respectable. Would be interesting to hear of those power transistors still work ;)


-F_D



-Eric

That Guy in South Africa...
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Offline mygoggie

Re: Quad 303 restoration
« Reply #5 on: December 31, 2018, 12:23:31 PM »
Looks to be an interesting project, the PCBs look fairly respectable. Would be interesting to hear of those power transistors still work ;)


-F_D

The PCBs have had a too hot soldering iron on them. I will see if I can recover the damaged tracks. Will post some pics.

Looking at the power trannies up close in real life I shudder ... will start stripping on the new year. Maybe that will work some miracles.
« Last Edit: December 31, 2018, 12:27:48 PM by mygoggie »
Herman

~ To heal the soul is to embark on a new journey. ~

Offline HB

Re: Quad 303 restoration
« Reply #6 on: December 31, 2018, 12:49:03 PM »
Nice :rubhands:
I have two of these. One works ok after a re-cap.
It has a hum once powered up though.
But sounds amazeballs!
The other needs extensive work and might not be worth the expense.
I wish I could just buy a complete kit LOCALLY as it's a mission for me to source parts.

Subscribed.
When You Come to a Fork in the Road, Take it!            [Yogi Berra]

Offline mygoggie

Re: Quad 303 restoration
« Reply #7 on: December 31, 2018, 02:02:17 PM »
Nice :rubhands:
I have two of these. One works ok after a re-cap.
It has a hum once powered up though.
But sounds amazeballs!
The other needs extensive work and might not be worth the expense.
I wish I could just buy a complete kit LOCALLY as it's a mission for me to source parts.

Subscribed.

I will post a parts list here. Maybe I can order two kits, one for you and one for me?
Herman

~ To heal the soul is to embark on a new journey. ~

Offline charles

Re: Quad 303 restoration
« Reply #8 on: December 31, 2018, 02:15:35 PM »
All the best with the restoration.

The mains transformer and the PCB's still looks o.k.

The power transistors would possibly even work after removal of the rust.


Offline HB

Re: Quad 303 restoration
« Reply #9 on: December 31, 2018, 02:18:42 PM »
I will post a parts list here. Maybe I can order two kits, one for you and one for me?
Fantastic.  Thank you very much.
That sounds like a plan.  :dop:
When You Come to a Fork in the Road, Take it!            [Yogi Berra]

Offline Family_Dog

Re: Quad 303 restoration
« Reply #10 on: December 31, 2018, 03:16:42 PM »
ChrisC mentioned he will most likely be placing an order for components from PartsExpress in January and has invited people to contact him for a joint once-off order. Contact him.


-F_D



-Eric

That Guy in South Africa...
*************************************
http://groups.yahoo.com/group/vintage_tube/
*************************************

Offline HB

Re: Quad 303 restoration
« Reply #11 on: December 31, 2018, 03:35:48 PM »
ChrisC mentioned he will most likely be placing an order for components from PartsExpress in January and has invited people to contact him for a joint once-off order. Contact him.


-F_D
I took part in the last one. It was such a pleasure dealing with Chris. So organized!
When You Come to a Fork in the Road, Take it!            [Yogi Berra]

Offline mygoggie

Quad 303 restoration - PCB underside
« Reply #12 on: December 31, 2018, 04:48:28 PM »
The three board's underside. Do not look too bad. Nothing that a resolder and resin remover will not clean.





Herman

~ To heal the soul is to embark on a new journey. ~

Offline mygoggie

Quad 303 restoration - Disassembled
« Reply #13 on: December 31, 2018, 04:56:34 PM »
I had an hour this afternoon before the braai starts. Stripped the unit into parts. Glad I did it as I found a number of dead shorts due to poor soldering.

The aluminium ends will clean up nicely with soda blasting. The rest I will send in next week to be chemically cleaned and plated.

Anyone knows of a face plate template for silk screening purposes? Otherwise I will have to spend some time making one up.

One thing I cannot get loose is the voltage selector in the top left hand corner. Anybody has an idea how the selector comes loose from the female socket? It is stuck ....







Herman

~ To heal the soul is to embark on a new journey. ~

Offline Family_Dog

Re: Quad 303 restoration
« Reply #14 on: December 31, 2018, 05:29:30 PM »
I would hazard a guess and say it should pull out but has probably corroded and is stuck fast. Liberally soak it with Q20 for a while?


-F_D



-Eric

That Guy in South Africa...
*************************************
http://groups.yahoo.com/group/vintage_tube/
*************************************