SX-1010 won't Power On...

No, he meant swapping out old transistors with new ones. I have noticed in some of your pic, you replaced the driver transistors and the predriver. I don't know if you replaced all the transistors. But that is what he meant.
 
No, he meant swapping out old transistors with new ones. I have noticed in some of your pic, you replaced the driver transistors and the predriver. I don't know if you replaced all the transistors. But that is what he meant.

Yes, ANY parts changes....
 
You have to re-check all 12 transistors again CAREFULLY for the correct leads in the correct locations. It should be working flawlessly.
 
Yes I think one or more of those 12 Q's blew when I powered up the unit (I think) with the Pin #15 wire broken during which I lost that output NPN. I went ahead the other day and took out all the output transistors (I was intending to take readings on the sockets but I wasn't exactly sure how to do it and what to look for) and powered up the unit hooked up to the DBT. Same thing, it goes dim and then goes full bright and starts flickering. I will check those 12 transistors carefully. The thing is though, before that Pin 15 wire broke and after I replaced those 12 transistors, the unit powered up fine and I even got faint audio on one channel. That is why I am thinking that something on the PA board went kaput upon firing up the unit with that emitter wire broken. In addition to the visual check on them, would you like me to take all those 12 components out and install new ones or take readings of them?
 
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You CAN'T power up the unit with NO outputs or dc feedback return path established. I didn't say to power it up at all, did I?

There are certain procedures I was going to walk you through after everything was installed. Now all transistors are suspect again. Even if they are installed correctly.

I just haven't been able to put in the time online lately - I had hoped that by the time you had parts, that I could.... but that hasn't worked out.

When I saw the posts regarding using the DBT, I cringed. Helplessly.

Things might have been ok until that wire broke...
 
While installing the 12 transistors, I took this as the pinout guide:

http://www.audiokarma.org/forums/showpost.php?p=2409536&postcount=411

I think there were no mistakes made while installing the transistors but after breaking the wire on Pin 15. I will take out all the 12 transistors in question out of the circuit board and test them individually. EW's thread, which I will take guide while testing, is extremely helpful as I really was wondering how to take measurements correct way. If there are any blown ones, I will let you know and install replacements upon your confirmation. Meanwhile powering up the unit with or without the DBT is strictly out of the question :nono:
 
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While installing the 12 transistors, I took this as the pinout guide:

http://www.audiokarma.org/forums/showpost.php?p=2409536&postcount=411

I think there were no mistakes made while installing the transistors but after breaking the wire on Pin 15. I will take out all the 12 transistors in question out of the circuit board and test them individually. EW's thread, which I will take guide while testing, is extremely helpful as I really was wondering how to take measurements correct way. If there are any blown ones, I will let you know and install replacements upon your confirmation. Meanwhile powering up the unit with or without the DBT is strictly out of the question :nono:

UH OH.........

With the to-92 cases that isn't true. The lead arrangements vary.
I know that the to-220 cases are the same, and maybe the to-126's, but NOT the to-92's.

NOW you are paying the price of abbreviating the information I provided.
512-KSA1013YBU [160v 1a .9w 50mhz 160-320hfe]
(+3 Extra)

I looked back and found this example of what I provided:
Q5 Q6 2sa628 to-92 BCE 25v .1a .15w 100mhz 800hfe , I would recommend:
two 512-KSA1013YBU to-92 ecb 160v 1a .9w 50mhz 160-320hfe $0.17 ea

The original transistor somewhere was Q5 (and Q6) a 2sa628
with a to-92 case
and an bce lead layout

while the replacement was a 512-KSA1013YBU
with a to-92 case
and a ecb lead layout

Look, THEY'RE DIFFERENT!!! SEE, there was a very good reason for all that extra stuff that I researched and included in the transistor data. I do the research once, then just cut and past the info of the original and replacement transistors as a block, again and again, so I don't have to go looking for it later. lazy me :D

go find an pull up the lists of transistors I originally posted - we'll need them. And searching through 38 pages of 570 posts at 3:20 am isn't feasible for me.
 
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I really didn't realize that to-92 was different. I should have known from your taking your time and adding the pinouts for every component. Anyway, I have a bit of homework ahead of me by the looks of it. I have copy-pasted EVERY part that has the pinouts you have posted from Page 5 to Page 38 into a text document. I will filter the double entries and make one clean list consisting of every component for every circuit board. I'll take it from there.
 
Just to be 100% clear on the matter, let's take one of the units for example, you said:

Q1 Q2 Q3 2sa726 to-92 bce : 512-KSA992FBU (ln)to-92 ecb 120v .05a .5w 100mhz 150-800hfe

I can see the ECB, the order is Base, Collector and Emitter. I checked the Data Sheet at Mouser for the above mentioned component which can be found at this link: http://www.fairchildsemi.com/ds/KS/KSA992.pdf According to the Data Sheet, the order is ECB which matches and confirms your pinout. So where have I made the mistake? If it matters at all, I have checked the Data Sheets at Mouser for EVERY SINGLE one of the 12 transistors and installed them according to those Data Sheets. In case you are thinking I took the pinouts in the picture below, I did NOT:

TransistorPinouts000001-1.jpg



All I have done was I checked the Pinouts on the Data Sheet at Mouser for each component and I took the below pictures as designation guides, just to know which hole E,C and B of each unit goes in on the circuit board:

TransistorPinouts000004.jpg


For example Q11 2sc945 to-92 ecb : 512-KSC1845EBU (ln)to-92 ecb 120v .05a .5w 100mhz 150-800hfe... The Data Sheet at http://www.fairchildsemi.com/ds/KS/KSC1845.pdf shows the ECB pinout. The second picture above suggests that for NPN transistors, Emitter goes in the direction of the arrow, Base to the opposite and Collector to the remaining hole. Let me try to explain it with the 512-KSA1013YBU you gave as an example in Post #570 (http://www.audiokarma.org/forums/showpost.php?p=2608822&postcount=570) It is a PNP transistor and the Mouser Data Sheet clearly shows the pinouts. Combining the information in the second picture above and the Pinouts in Mouser Data Sheet I installed the tansistor as shown in the picture below:

KSA10103.jpg




What is the problem here? I am having a hard time believing that I made a mistake. :dunno:
 
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I have filtered the entire post and pulled up the list of the transistors, not just for the PA Board but the whole unit. Here is the list just for the PA Board:

Amplifier Board:

Q1,Q2,Q3 2sa726 to-92 bce : 512-KSA992FBU (ln)to-92 ecb 120v .05a .5w 100mhz 150-800hfe
Q4 2sb528 to-202? bce : 512-KSA910YBU to-92 ecb 150v .05a .8w 100mhz 40-240hfe
Q5,Q6 2sc1451 to-39 npn ebc : 512-KSC2310YBU to-92 ecb 150v .05a .8w 100mhz 40-240hfe
Q7 2sd358 to-202? bce : 512-KSC2690AYS to-126 ecb 160 1.2a 20w 155mhz 35-320hfe
Q8 2sb528 to-202? bce : 512-KSA1220AYS to-126 ecb 160 1.2a 20w 155mhz 35-320hfe
Q9 2sc1448 to-220 bce P: 512-KSC2073TU npn to-220 bce 150v 1.5a 25w 4mhz 40-140hfe
Q10 2sa740 to-220 bce : 512-KSA940TU_Q pnp to-220 bce 150v 1.5a 25w 4mhz 40-140hfe
Q11 2sc945 to-92 ecb : 512-KSC1845EBU (ln)to-92 ecb 120v .05a .5w 100mhz 150-800hfe
Q12 2sa733 to-92 ecb : 512-KSA992FBU (ln)to-92 ecb 120v .05a .5w 100mhz 150-800hfe
 
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Nearly all Japanese numbered transistors (2SA, 2SB, 2SC, 2SD) have the collector as the center pin. Knowing this, it is a 10 second job to locate the base and emitter with the diode test of the meter.

If the base is the center pin, things get harder. You need an accurate data sheet, or a transistor tester of some sort so you can ferret it out.

As far as this statement:
The Data Sheet at http://www.fairchildsemi.com/ds/KS/KSC1845.pdf shows the ECB pinout. The guide at http://www.audiokarma.org/forums/sho...&postcount=411 suggests that for NPN transistors, Emitter goes in the direction of the arrow, Base to the opposite and Emitter to the remaining hole. The unit in question being a to-92, have I installed it wrong? If so, what are the correct designations? If you answer that, I can see my mistake much more clearly.
...I have very little idea what you are confused about.

One, forget that pic you have posted. Forget it. It is maybe useful to determine what the case style is, but I do have a more comprehensive pic.

As with your pic, it is useful to identify the case style, but NOT the pinout. Manufacturers decide for themselves where they want to put the emitter, collector, and base. (Note that with power transistors that are commonly attached to heatsinks, messing with the lead arrangement is a LOT less likely, and with the very large power transistors, almost unheard of. But NEVER ASSUME ANYTHING! Check for yourself!)

If you cannot identify the base, emitter, and collector on a physical part you hold in your hand, AND you cannot identify these same transistor leads by looking at a schematic symbol (which is what the the quote above kinda sounds like), I'm afraid that your chances of repairing this receiver are remote in the extreme.

In the off chance that there's something about the schematic symbol that is confusing you about the location of the emitter, I offer this pic:

(the arrow does not point to the emitter, it IS the emitter, and points in the direction of conventional current flow (positive to negative)
 

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Thanks for the picture Glen, it is quite helpful. Though it looks like the 3rd picture I attached in Post #573 above doesn't it? As for getting confused, I wasn't. I was very careful while installing the transistors and I triple checked everything. I think I failed to make myself clear and Mike misunderstood when I told him that I used the Picture in Post 411. I assume he thought I was taking basis the to-92 in that picture (the crossed out picture above) where the Base is indeed the middle pin as you mentioned in your above post. However, I used the Manufacturer's Data Sheet. I imagine that is what Mark was confused about. If I REALLY thought the middle pin was the Base, I would have installed roughly about 10 PNP incorrectly, which probably would have been fatal, not that it already isn't.
 
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Sure...but you added that pic after my post. ;)

I know it's only three leads, but it's still easy to screw up.
 
Using the datasheets from mouser, and recognizing that the pinouts can be very different from each other and the originals - and one picture does NOT tell the whole story - tells me your transistors should be in OK.
 
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One picture indeed does not tell the whole story, I should have mentioned the Data Sheets right from the start. Yes, I went through the Data Sheet for each individual unit and made sure that the Emitter, Base and Collector for every unit went into the right holes on the PA Board like I did on the Protection Board. Probably a few of them are bust caused by that Pin #15 and my foolishness. As you instructed, I will take them all out from the circuit board and test them one by one. I just hope the Pin #15 incident did not reflect damage on any other area of the receiver.
 
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