Qguy's Vintage Pioneer SX1050 restoration

[qguy]

A few weeks ago I got a Pioneer SX1050. it had a few issues, outer finish was not that great. woofer thumps when you power on, same thing happens when you click some of the switches. Tone defeats control will send a thump to the woofer after a few hours of use

Decided it was time for a restoration.....

Here are some pics of the before and after..



Nude with CD for size comparison





The wooden case before



after



Power supply protection circuit before



after



Power supply board A before



After



Power supply Board B before



After



Where is the heat sink ???



There it is



Heating the front panel walnut end caps before spraying on Cayin oven toaster



after spraying



Flat amp board before



After



My capacitor collection will add more to this,.. still need to do the tuner section and Tone control section

[mikeer2002ph]

Nice! Now that's a responsible audiophile .. replacing caps as needed since caps have a design life of just 5-7 years of continuous use (equivalent "power on" hours).

[philpath]

Is there an improvement in the sound after the electrolytic tune up?

[qguy]

Dont know yet, will post once I am done, for all you know this amp may never produce music again

Is there an improvement in the sound after the electrolytic tune up?

[joejet]

I envy guys like you qguy. I wish I had learned electronics like you had so i can tinker with my own stuff. I've always loved electronics but I never had the chance to learn even a bit.
Anyway, that's a pretty nice receiver you're working on. And you're doing really good on your restoration. Keep us posted Sir.

[qguy]

WHOA .. Who said I learned electronics ??? I have a screwdriver, actually cordless drill driver makes blowing amps a lot faster and I can plug a soldering iron.. thats the extent of my electronics skills

I envy guys like you qguy. I wish I had learned electronics like you had so i can tinker with my own stuff. I've always loved electronics but I never had the chance to learn even a bit.
Anyway, that's a pretty nice receiver you're working on. And you're doing really good on your restoration. Keep us posted Sir.

[Tjaderman]

Nice job, Q!

[endrik35]

Very nice resto qguy! I need to recap the filter caps of my muse amp. They're rated at 10,000 microfarads at 100v. Can you give me an advice on where to source this? I need a pair. Tia!

[qguy]

Try Watson Electronics / Pacific Electronics / Eleshop / Deeco their all in Raon area. These were the recommended shops by some of the DIY in Pinoydvd. I was able to source most of my parts at Watson. although bigger caps is harder to get.

Very nice resto qguy! I need to recap the filter caps of my muse amp. They're rated at 10,000 microfarads at 100v. Can you give me an advice on where to source this? I need a pair. Tia!

[georgepogi69]

nice job Q....bilib ako sa patience mo...i know your SX will sing for a long time...

[qguy]

When it comes to this hobby, you dont need patience

nice job Q....bilib ako sa patience mo...i know your SX will sing for a long time...

[Octaver]

When it comes to this hobby, you dont need patience

nice job Q....bilib ako sa patience mo...i know your SX will sing for a long time...

Be careful Qguy if you don't have patience, you will become a Patient
Kidding aside! Please take note of the capacitor polarity and quick connector orientation
don'r forget to double check the solder you did not causing Short to other connections.
Congrats! Hope to hear a Success Restoration Process from you!

[qguy]

Cleaning output transistors....YIKES

At first I did not want to touch the output transistors for fear of screwing up, I asked around what is the benefit of cleaning / regreasing the transistors. Response was that for older units the thermal grease dries up and no longer conducts heat away from the transistor, resulting in over heating transistors when the amps is pushed too hard, basically you end up with a burnt out transistors. kinda like changing oil on an old car before racing it . Since I "race" my amp on occasions ;D I decided to go for it...





cleaned transistor and new insulation mica
Basically you remove the transistor, cleaned with tissue or clean rag. Apply THIN layer of NON CONDUCTIVE Thermal grease on both sides of the insulation mica and put the transistors, clean the pin and install....



I also regrease all those smaller three legged transistor
I used Unick thermal grease, 80 php at Watsons for a small size tube

This was one of the easiest process in the restoration.. a bit messy though as the grease sticks to everything, have a roll of tissue when you do this

[qguy]

Finally back on duty

[joejet]

Beautiful!

[hypertriode]

Finally back on duty

[mikeer2002ph]

Cleaning output transistors....YIKES

At first I did not want to touch the output transistors for fear of screwing up, I asked around what is the benefit of cleaning / regreasing the transistors. Response was that for older units the thermal grease dries up and no longer conducts heat away from the transistor, resulting in over heating transistors when the amps is pushed too hard, basically you end up with a burnt out transistors. kinda like changing oil on an old car before racing it . Since I "race" my amp on occasions ;D I decided to go for it...

cleaned transistor and new insulation mica
Basically you remove the transistor, cleaned with tissue or clean rag. Apply THIN layer of NON CONDUCTIVE Thermal grease on both sides of the insulation mica and put the transistors, clean the pin and install....

I also regrease all those smaller three legged transistor
I used Unick thermal grease, 80 php at Watsons for a small size tube

This was one of the easiest process in the restoration.. a bit messy though as the grease sticks to everything, have a roll of tissue when you do this

You may also want to consider the thermal compound meant for PC processors on your next 'maintenance' (shin-etsu G751 or Arctic Silver 5 [as5] - silver/silicone thermal compound) they have a higher heat conductivity index as compared to the normal silicone thermal and it stays 'wet' - doesnt dry up like the raon variants which requires cleanout/reapplication every year or 2.

Caveat with AS5 or shin-etsu G751 is you only apply a very very thin layer, it's also more expensive than your raon thermal compound variants but more than compensates the price with better 'tracking' of the bias transistor/thermal diode since heat isnt being kept 'long' on the transistor package

[joy_francisco]

.

[qguy]

I was advised to stay away from thermal compounds designed for PC as some of them are electrically conductive, must be the silver content, which makes it more conductinve to heat but makes it conductive to electricity. I think processors get away from this as the case of the processor is plastic and the chassis of the PC is not used as ground.

The grease on the small transistors were actually still wet after 36 yrs.. the one on large heat sink was dried and powdery

You may also want to consider the thermal compound meant for PC processors on your next 'maintenance' (shin-etsu G751 or Arctic Silver 5 [as5] - silver/silicone thermal compound) they have a higher heat conductivity index as compared to the normal silicone thermal and it stays 'wet' - doesnt dry up like the raon variants which requires cleanout/reapplication every year or 2.

Caveat with AS5 or shin-etsu G751 is you only apply a very very thin layer, it's also more expensive than your raon thermal compound variants but more than compensates the price with better 'tracking' of the bias transistor/thermal diode since heat isnt being kept 'long' on the transistor package

[tony]

i seldom use silicon grease nowadays...they are messy....

i use these silicon pads instead....


i also use Kapton tapes...