pioneer sx 1010 problems

The referenced picture shows an AWM-062 protection board with apparently a ztx-1056a in the Q7 position (zetex e-line package) as well as the Q6 position quite close to the pins 9 & 10 with the diode attached, anode to pin 9 and cathode to pin 10.

If there is a post I did with an error that you have found please post a link to it.

The Q7 position - originally a 2sc1384 - turns on (and off) the protection relay by conducting current collector to emitter and through r28 (220 ohms) to ground and energizing the relay coil.

The Q6 position - originally a 2sc945 - discharges C6, 100uf 16v , which is the time delay capacitor, through R27 through the 22 ohm resistor to ground. This subjects Q6 to high pulse currents through it every time the circuit turns the relay off.

Both can benefit from a replacement, and the 2sc945 in Q6 position is a bit marginal for the application, a higher current transistor with lots of gain is preferred.

The ztx1056a is no longer being restocked by our usual suppliers, and may be a special ($$ quantity) order item.

Thus a new transistor has been selected.
OK, like EchoWars says, the relay pull in current is weak (not a short buzzing, but the relay buzzing as it tries to pull in), so replace the 2sc1384 (ecb) with 512-KSD1616LBU (ecb), as the zetex will no longer available.

2sc1384 to-92 npn ecb 50v 1a 1w 85-240hfe 200mhz

Q10 - 512-KSD1616LBU to-92 ecb 50v 1a 0.75w 160mhz 135-600 $0.09 ea
C245 - 647-UPW1H010MDD 1uf/50v $0.10 ea
C243 - 647-UPW1H100MDD1TD 10uf/50v $0.09 ea
C244 - 647-UPW1H101MPD 100uf/35v $0.22 ea

Maybe you want to pursue other parts at the same time to pad out the order? (as in further postings etc...)


the 1616 is fine, and the 1616a has more voltage with slightly less gain.

512-KSD1616ALBU to-92 ecb x60v 1a 0.75w 160mhz 135-400 $0.09
512-KSD1616LBU to-92 ecb 50v 1a 0.75w 160mhz 135-600 $0.09
 
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no, it's a good question:

The power supplies are heat stressed, Pioneer runs them hot, and if the ventilation is restricted - they get way too hot, thus replacement is a good idea. The protection circuits Q5 & Q6 transistors are also stressed in different ways, and the modern ztx-1056a replacements are far more robust ( 6 AMPS pulse current, 3 amps continuous), and the extra diode put across pins 9 & 10 helps alleviate some of that stress too.

The amps are NOT run that "close to the edge". there are a few transistors that can inspire mistrust, but the dangers of a wholesale replacement causing damage are greater than the chances of eventual failure. I include MYSELF (not just "noobs") in the group that should think long and hard before doing a complete replacement of transistors in the 1010 amplifiers.

Just as an example, the EchoWars 1250 at the fest that he "did the works on" still had the original outputs - but I didn't ask about the rest of the transistors in the amp....

If it ain't broke - don't fix it.

mark this is the post i was questioning. now for Q6 & Q7 i have 4 new ztx-1056a transistors that i ordered from mouser a few months ago. should i use them???
 
mark this is the post i was questioning. now for Q6 & Q7 i have 4 new ztx-1056a transistors that i ordered from mouser a few months ago. should i use them???

Yes. As long as you have them, use them....

I just have to keep an eye on the future for things like "I can't find ztx-1056a's mentioned in the thread" come back to bite me.

thanks for the link to the post, I fixed it.... must have been a momentary memory lapse....
 
the tone switch is starting to get real staticky now. when i turn it on i have to flip it a few times for the sound quality to come back. i have used deoit twice on it back at the begining of the year. shoud i just change this switch when i get back at the cap replacement? if so where should i get them from? is there a mouser # for the switches
 
1. No.
2. There is no source for these antique parts.
3. No, Mouser doesn't carry them either.

I've never seen one of these Pioneer's where the switch was so bad that I had to change it out. DeOxit will do the job fine when used properly.
 
on the poliester film caps that replace the electrolitics on awm-062 is there not a positive or negative lead
 
on board awm-062 the ztx 1056-a transistors are suposed to be installed as in this picture right. emiter is the left terminal, base is the center and collector is right???? i was looking at my other unit and it looks as if the trans are in different positions. now that is with what may be original??? im not shure though. its a parts unit that has been gone for years. i am also judging it by the flat surface cut into the trans, im not shure if thats a proper way to view it or not. im including a pic of my board. the one with the ztx-1056a is from a post by zero junk
 

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Look at the arrow on the circuit board. Your transistor is either NPN or PNP.

The transistor specs will tell you whether it is ECB, BCE or whatever being the emitter, collector, base orientation. Install them per this.


edit.IT's looking at the transistor from the pin side with the flat side being the front.
 

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ok so there correct then right. i bought the 1056a's and installed them as your picture showed. the pictures i posted were my board before the recap and trans replacement. and the other was from a post of yours on my page. my board now looks the same. do they change the layout for trans leads per manufacturer or are they a general platform? did i get it right???
 

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As much as I tried, I couldn't distinguish which way the flat was facing in your picture.

You have to pay CLOSE CAREFUL attention to the datasheet, zetex is different...the rounded side is printed on,

the drawing on the datasheet does show the layout clearly - BUT you could be used to seeing the printing on the flat side (most others) versus the printing being on the rounded side on the zetex.

With the flat facing you, AND the leads facing DOWN, the layout is ebc. IGNORE the printing of the transistor number.

edit: in the Q7 position the collector is connected to pin 9, directly, follow the foil....
 
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change of subject,,, when i go to re clean all the switches, i have a whole can of de-oxit g5 gold. what can i use that for???? i have d5 and faderlube allready
 
change of subject,,, when i go to re clean all the switches, i have a whole can of de-oxit g5 gold. what can i use that for???? i have d5 and faderlube allready

gold: protectant.... switches after deoxiting, connectors, jacks rca included....
 
there are a little over 1,500 ztx-1056a transistors avaliable at mouser for shipment. they are no longer being stocked
 
there are a little over 1,500 ztx-1056a transistors avaliable at mouser for shipment. they are no longer being stocked

a similar situation happened with the ksk30 50v jfets, and while I thought there was plenty of cushion and the parts would be available for a long time, the opposite was true, they disappeared within a week.

But at $1.51 ea / $0.78 in 100's and $0.468 in 1000's it might be a bit slower...

even so, that's why I stopped recommending them - eventually the advice will be out of date...
 
since i am new at this i figured i would rebuild one board at a time and test. as you have seen,, i remove the board, clean, and rebuild. i then re wrap with hemostats and solder. i guess im doing good so far because im listening to it right now. tomorrow im doing the muting and eq circuits. i thank everyone for there help. its put me this far
 
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