A G-8000 followed me home

Well folks let the fun begin....
I'm not sure if replace transistors (I have all them on stock), I replaced every one of them on my 9090, AU-999 and Pioneer SA-7500 with very positive results, but not sure on this one.
Any advice?

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This transistors looks like crap TR05, 06, 07, 08 on F-2806 (driver boards) they are 2SC1628 and 2SA818 ... but to be honest I have no idea if is better just leave them alone

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There are no real problematic transistors in the G series, but if you were keen you might replace the transistors in the power supply regulators, they and fully turned on all the time so get a much harder time than the other transistors in the amp..
Apart from that I would leave the rest of them....
Getting hard to find TO220 and TO126 replacements with enough gain and ft these days...
 
There are no real problematic transistors in the G series, but if you were keen you might replace the transistors in the power supply regulators, they and fully turned on all the time so get a much harder time than the other transistors in the amp..
Apart from that I would leave the rest of them....
Getting hard to find TO220 and TO126 replacements with enough gain and ft these days...
Okie dokie Kevzep..... thank you very much for your pointers.
What do you think about the VD1212 on this unit?... should I replace them with 1N4148 in series?
BTW I couldn't find any ''fusistor'' on this unit... just N.I.R resistors.

Looks that this will be an easier job that I anticipated. :beerchug:
 
Okie dokie Kevzep..... thank you very much for your pointers.
What do you think about the VD1212 on this unit?... should I replace them with 1N4148 in series?
BTW I couldn't find any ''fusistor'' on this unit... just N.I.R resistors.

Looks that this will be an easier job that I anticipated. :beerchug:

NIR same thing, need to replace those, I can have a look at the schematic when I get to the office and point a few out that need doing...

Yeah VD1212's need to go, 1N4148 in series is the way to go for those.
 
NIR same thing, need to replace those, I can have a look at the schematic when I get to the office and point a few out that need doing...

Yeah VD1212's need to go, 1N4148 in series is the way to go for those.
Awesome!! thank you very much Kev
 
Oh sorry, busy day, I'll have look when I can. There's not many resistors that need replacing......
 
Don't worry my friend I can look for those buggers.

thank you!:beerchug:

Here we go, on the Power-supply board F2809, R05 and R06 220Ω 3 watt, replace those. On the Driver boards F2806 R17 and R20 150Ω 1/4 watt.
So just use metal film and mount them up off the board a bit as they have a fair bit of constant current running through them so they do get warm, and this is why they fail and go hi resistance, they are stressed all the time.
I'd place a bet saying if you measure them, they won't be on spec.
Those are the resistors I have found give trouble in these amps, everything else is all good, these amps are very reliable and a solid design.
Make sure you clean all those switches really thoroughly, especially the tape monitors and 4ch adapter (not sure if the 8000 has one, the 9000 does).
 
Here we go, on the Power-supply board F2809, R05 and R06 220Ω 3 watt, replace those. On the Driver boards F2806 R17 and R20 150Ω 1/4 watt...
Awesome... ordering right now!

Update: so far this week I replaced every cap on F-2806,F-2807,2808 and caps, relays, and vd1212 on 2809. So far so good... I haven't mess up the unit.:beatnik:
 
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The change out caps comment----

That is a whole can of opinions of which there are many :)
Not all caps are failing, not all boards have cold solder joints, not all units have corrosive glue damage. So, as the saying goes, 'what you gonna do?'
All the switches need to be cleaned. To get to those switches and do it right you will have to get into major board teardown. If you have the board torn down well lookie there the caps are right where you can get at them. I for one find getting at those boards as time consuming as replacing caps and reflowing solder points. You could just change out the known suspects, Sanyo sky blue low value electrolytics and tantalums which are usually in the audio path but why when for just a few $$ more and a short amount of time you could change the others as well And that power supply, 40 years of slow toasting away, why not do a little preventive work here as well and upgrade those toasty critters to 105c rated panasonics. Gives you a chance to check supply voltage too. Oh, and while you are in there cleaning and such its a good time to replace the pesky vd1212 double diodes.
Now you have everything apart lets also look at the service manual and get after all those fuse-able resistors, oh and re-greasing the outputs is a good idea too. The finicky offset and bias trimmers could use a upgrade to multi turn potentiometers as well

As you now see its not just cap slinging but more a matter of opportunity. If the piece is one you find will never leave your stable of gear then my thought is do it once, do it right, then put it in the rack and enjoy for years to come

Short version of the above --- if the unit is all apart do everything once and be done for good.
Your gear will thank you for it.
-Lee
 
I hate that glue!

jeez... something happened and lost a huge explanation that I have done to this unit... :mad:.

Well... just in case someone wonder, the unit is almost ready.
I replace the filter caps, the old ones gave some weird readings, the unit is sounding great with my bench test speakers (bose 161 -I know, I know :rflmao:- ).

As soon I install some binding posts.... Let's crank it up on some real speakers and see how it goes.

Thank you very much guys.

Cheers
 
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Wow! I think this is my favorite Sansui of the herd!
I don't like the case (plastic and cheap vinyl) but nothing that can't be fixed. It is indeed a great sounding unit.
 
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