pioneer sx 1010 problems

ok im re capping my last board on the list awg-027 control amplifier assy. is there no need to change the 4 caps in each amp board???? i read that in a few post and was just curious? i realise that they will be a pain to remove but if it will improve sound quality i have no problem doing it.
 
ok im re capping my last board on the list awg-027 control amplifier assy. is there no need to change the 4 caps in each amp board???? i read that in a few post and was just curious? i realise that they will be a pain to remove but if it will improve sound quality i have no problem doing it.

Yes, replace them. They are input coupling and feedback, they can and do affect sound quality.

If you haven't purchased them yet, figure out if it really uses c1 & C2, plus on the higher end units they use metalized foil caps in those input positions.

C4 smooths the offset and C8 is the feedback capacitor.

While it's open, regreasing the output transistors is a good idea.
Use thin grease layers so there's minimal squeeze out, don't torque it down until the socket is in it's recesses in the heat sink and use an ohmmeter to check for shorts to the heatsink. Get one good spot, probe to heatsink, and then another for the other probe to be sure both are zero ohm connections, then lift one probe and check the transistors, finally go back to the first "other" spot and re-verify zero ohms to be sure the stationary probe didn't slip or loose contact.
 
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i ordered all transistors for this unit a few months ago since they are becoming obsolete. with the suggestion of re greasing the output transistors , i was wondering if i should install the new ones i have or keep using my originals
 
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i ordered all transistors for this unit a few months ago since they are becoming obsolete. with the suggestion of re greasing the output transistors , i was wondering if i should install the new ones i have or keep using my originals
do i need new mica strips or can i use the originals
 
They can be reused if they weren't glued down with clear glue.

Just carefully clean off the white stuff. Don't bend them, they are fragile in some directions.

New are still available, if necessary.


mouser.com
534-4662 to-3 mica insulators $0.16 each
 
i ordered all transistors for this unit a few months ago since they are becoming obsolete.
They are already obsolete, if by 'obsolete', you mean "no one has made them for 15+ years and anything you buy with that number on it now is almost certainly a Chinese counterfeit and will probably blow-up as soon as power is applied and undo all my hard work and loving effort".

So yeah, if that's what you mean by 'obsolete', then sure, those outputs are obsolete.
 
They can be reused if they weren't glued down with clear glue.

Just carefully clean off the white stuff. Don't bend them, they are fragile in some directions.

New are still available, if necessary.


mouser.com
534-4662 to-3 mica insulators $0.16 each

what about installing my new output transistors?????
 
HUH??

Use NEW thermal grease? Don't use too much? On BOTH sides of the mica?

Don't crack the sockets, by missing the recesses for the socket in the heat sink BEFORE tightening? It keeps them centered so there are no short circuits to the heat sink.

Ohm test for shorts to the heat sink before applying power?

That kind of stuff?
 
the new transistors i have are from mouser. 863-MJ21194G (npn) & 863-MJ21193G (pnp). both rated at 16A 250V 250W. should i have not ordered these? if there right should i install them or keep running the originals?
 
They are fine.

As far as obsolescence, you may have taken a previous post about the TO-3 transistors that I concocted and read it to mean that this style of transistor was going to be disappearing any day. Probably not the case, but due to the fact that On-Semi is one of the last trustworthy fabs that is still cranking out good quality TO-3 transistors, it doesn't hurt to have a few spares.

The TO-3's will disappear eventually, but I'd say they have a few years to go yet.
 
In my not so humble (on this subject :stupid: ) opinion, they are superior to the originals.
 
In my not so humble (on this subject :stupid: ) opinion, they are superior to the originals.

im getting confused?????? do i run the original output transistors or install my new ones and keep the old ones for spares????? im waiting on a solid answer before i do anything. im just looking at her gutted right now before i do anything
 
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Sometimes, a man just has to make a decision. Assuming the originals are not blown, this is strictly your call.
 
i guess im gonna stick with the originals since they still work

That is what I did with my SX-1250. I found the outputs are fine and even though I'd like to get the new ones in, I decided to keep the old ones in. On the other hand, my SX-1010 has the new set of outputs because only one channel has the originals and the other channel has 2 different brands of outputs. You did fine. I'd just keep the originals unless there's a real reason to replace them.
 
how important is c2 on board awh-032? i missed that cap and dont like the idea of ordering 2 parts at less than a buck each and paying 7.50 for shipping
 
how important is c2 on board awh-032? i missed that cap and dont like the idea of ordering 2 parts at less than a buck each and paying 7.50 for shipping

That's the input coupling capacitor, when it leaks electrically your offset will go off the charts, and as it looses value the bass response will diminish.

Are you SURE it uses C1 and C2, sometimes there are factory mods that whittle it down to one of a different value.

Frankly, I have done that before, and on personal units, I get the part with my next order and tape the bag to the back of the unit, for later installation. If something starts sounding bad, it gets me motivated to do it sooner.
 
on board awh-032 can i use poliester caps in place of both c1 & c2? i found a previous post that called for mouser # 5989-100v.68 for c1, and i have found 5989-100v1.5f for c2. i am unshure of what the difference is between the electrolitic and poliester are other than the electrolite. what are the differences??? i am planing to make a hopefull finall order from mouser friday and needed to get some input from the masters. i know i need insulators to be able to regrease my outputs so i figured id get the rest
 
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