1250 recap question

[markthefixer]

By your annotations of the parts lists I have posted, you have STRIPPED AWAY VITAL INFORMATION I ALWAYS include with it. NOW you are paying the price. The "lot of reading" wasn't nearly enough.

First you need to learn about what the three transistor leads are about, and identifying which is which and where it goes according to the symbol. Then you will see that my parts list include lead arrangements - which assume the transistor lettering (and flat) are facing you and the leads are facing down, then go left to right.

The big TO-220's with the metal mounting plate are hard to reverse, but the smaller ones are, but my specified replacements are usually E C B as a rule of thumb BUT we ALWAYS CHECK...

But you really should start here and follow ALL the links...

http://www.audiokarma.org/forums/showthread.php?t=331932&page=5

here's a preview, DO YOU SEE these symbols on the boards you are working on?:

e is always the arrow on one angled line (direction can be out (npn) or in (pnp) towards the base)
b is always the flat line the other two lines come out if at an angle
c is always the angled line without the arrow

letters can be smudged or illegible, while the symbols are hard to mistake and pretty language independent
pioneer doesn't use letters, if there is a symbol. sometimes in a linear hole arrangement, there is only an 'e'.... with no room for a symbol.

 

[bdblkta]

Thanks for your help Mark. As per your instructions I read all available information about the transistors and managed to get them installed. I had however left out a few of the bias pots on my order and will have to wait until friday for them to be brought to me(My uncle lives near Mouser and will pick them up for me).
I hope to power up the unit this weekend and was hoping you could point me in the right direction for doing so. I have access to a DBT, I have a DMM and a service manual. Josh

 

[markthefixer]

That's also out there in the 1250 threads to be found. A huge amount to type if starting over from scratch.

 

[bdblkta]

Alright so I had decided not to go forward with the power up after reading some more and would like to go ahead and do the transistors on the amp boards (awh 048). I have found a few threads with data about the transistors but have not found which are specific to the amp boards, what locations on the board nor the ECB layout. If this has been posted I can not find it.
Thanks for all of the help.

 

[bdblkta]

Alright so this is from an old post but I am really trying to figure this out and have been in the service manual trying to learn where all of these parts go but I am still not 100%.
Mark I apoligize if I'm bringing in an older post that is not correct, I figured it would at least be a start.

Originally Posted by markthefixer
sx-1250 amplifier , "driver cards" board : AWH-048 replacement parts:

Mouser parts numbers, a mix of Fairchild (512-) and ON-Semi (863-)

differential inputs, better off if the hfe is matched
2sa750 to-92 ecb 50v .05a .25w 100mhz hfe:450
twenty: 512-KSA992FBU (ln)to-92 ecb 120v .05a .5w 100mhz 150-800hfe $0.05 ea

bias / vas
2sa858/2sc1439 to-92 ecb 150v 0.5a .5w 100mhz hfe:150
two: 512-KSA910YBU to-92 ecb 150v .05a .8w 100mhz 40-240hfe $0.12 ea
two: 512-KSC2310YBU to-92 ecb 150v .05a .8w 100mhz 40-240hfe $0.11 ea

pre-driver
2sa899/2sc1904 to-126 ecb 150v .05a 1w 100mhz hfe:150
two:x 512-KSA1142YSTU to-126 ecb 180v .1a 1.2/8w 200mhz 100-320hfe $0.21 ea
two: 512-KSC2682YSTU to-126 ecb 180v .1a 1.2/8w 200mhz 100-320hfe $0.31 ea

drivers
2sb630/2sd610 to-220 bce 200v 2a 25w 4mhz hfe:80
two: 863-MJE15032G to-220 bce 250v 8a 50w 30mhz hfe:70 $0.87
two: 863-MJE15033G to-220 bce 250v 8a 50w 30mhz hfe:70 $0.87
edit: use the KSA / KSC's not the MJE's - Vbe turnon is a bit lower and results in too much bias at times 4/25/09 mtf
drivers
2sb630/2sd610 to-220 bce 200v 2a 25w 4mhz hfe:80
two: 512-KSA940TU_Q pnp to-220 bce 150v 1.5a 25w 4mhz 40-140hfe $0.54
two: 512-KSC2073TU npn to-220 bce 150v 1.5a 25w 4mhz 40-140hfe $0.54

power outpu
2sb600/2sd555 to-3 200v 10a 200w 14mhz hfe:70
four: 863-MJ21194G to-3 NPN 250v 16A 250W 4mhz 8-75hfe $4.10
four: 863-MJ21193G to-3 PNP 250v 16A 250W 4mhz 8-75hfe $4.10

overcurrent detector
2sc869 to-92 npn bce 50v 30mA .2w 150mhz hfe:35
two: 512-KSC2310YBU to-92 ecb 150v .05a .8w 100mhz 40-240hfe $0.11 ea



mouser parts for both awh-048 boards

20 - 512-KSA992FBU for q1,q2
4 - 512-KSA910YBU for q5,q6
4 - 512-KSC2310YBU for q3,q4
2 - 512-KSA1142YSTU for q8
2 - 512-KSC2682YSTU for q7
2 - 512-KSA940TU_Q for q10
2 - 512-KSC2073TU for q9
2 - 512-KSC2310YBU for q11


I believe I had read to order the 20 512-KSA992FBU for q1,q2 so that they can be tested and matched. Is this correct?


I also dont know where these go, or how many of each to do both boards?
one: 522-ZTX1056A NPN TO-92E ebc 150v 3a 1w (Vce(sat)=0.3v @ 3a) 120mhz 30-1200 hfe relay driver transistor
four - 863-MJ21194G
four - 863-MJ21193G

Thank you again for all of your help. Josh

 

[markthefixer]

whew, lotta typing to answer..


I believe I had read to order the 20 512-KSA992FBU for q1,q2 so that they can be tested and matched. Is this correct?
matching doesn't make sense if you don't have the tester to do it, and it costs too much to get it for just doing matching, also the "match" is different in the unit than on a tester. Just get a minimum of four, and maybe spares, in case we have goofs...


one: the 522-ZTX1056A NPN TO-92E ebc 150v 3a 1w (Vce(sat)=0.3v @ 3a) 120mhz 30-1200 hfe relay driver transistor
IS an "obsolete" protection relay driver transistor that cannot easily be obtained, so
awm-091 Q6 was a 2sc1166, the replacement = ksc2690
512-KSC2690AYS to-126 ecb 120/a160 1.2a 20w 155mhz 35-320hfe $0.40

these:
four - 863-MJ21194G
four - 863-MJ21193G
are the power output transistors, the silver ovals on the heat sinks under the metal covers on the outside of the unit.


This (old, erroneous) stuff:
********************
Originally Posted by markthefixer
sx-1250 amplifier , "driver cards" board : AWH-048 replacement parts:

Mouser parts numbers, a mix of Fairchild (512-) and ON-Semi (863-)

differential inputs, better off if the hfe is matched
2sa750 to-92 ecb 50v .05a .25w 100mhz hfe:450
four: 512-KSA992FBU (ln)to-92 ecb 120v .05a .5w 100mhz 150-800hfe $0.05 ea

bias / vas
2sa858/2sc1439 to-92 ecb 150v 0.5a .5w 100mhz hfe:150
two: 512-KSA910YBU to-92 ecb 150v .05a .8w 100mhz 40-240hfe $0.12 ea
two: 512-KSC2310YBU to-92 ecb 150v .05a .8w 100mhz 40-240hfe $0.11 ea

pre-driver
2sa899/2sc1904 to-126 ecb 150v .05a 1w 100mhz hfe:150
two:x 512-KSA1142YSTU to-126 ecb 180v .1a 1.2/8w 200mhz 100-320hfe $0.21 ea
two: 512-KSC2682YSTU to-126 ecb 180v .1a 1.2/8w 200mhz 100-320hfe $0.31 ea

drivers
2sb630/2sd610 to-220 bce 200v 2a 25w 4mhz hfe:80
two: 863-MJE15032G to-220 bce 250v 8a 50w 30mhz hfe:70 $0.87
two: 863-MJE15033G to-220 bce 250v 8a 50w 30mhz hfe:70 $0.87
edit: use the KSA / KSC's not the MJE's - Vbe turnon is a bit lower and results in too much bias at times 4/25/09 mtf
drivers
2sb630/2sd610 to-220 bce 200v 2a 25w 4mhz hfe:80
two: 512-KSA940TU_Q pnp to-220 bce 150v 1.5a 25w 4mhz 40-140hfe $0.54
two: 512-KSC2073TU npn to-220 bce 150v 1.5a 25w 4mhz 40-140hfe $0.54

power outpu
2sb600/2sd555 to-3 200v 10a 200w 14mhz hfe:70
four: 863-MJ21194G to-3 NPN 250v 16A 250W 4mhz 8-75hfe $4.10
four: 863-MJ21193G to-3 PNP 250v 16A 250W 4mhz 8-75hfe $4.10

overcurrent detector
2sc869 to-92 npn bce 50v 30mA .2w 150mhz hfe:35
two: 512-KSC2310YBU to-92 ecb 150v .05a .8w 100mhz 40-240hfe $0.11 ea



mouser parts for both awh-048 boards

20 - 512-KSA992FBU for q1,q2
4 - 512-KSA910YBU for q5,q6
4 - 512-KSC2310YBU for q3,q4
2 - 512-KSA1142YSTU for q8
2 - 512-KSC2682YSTU for q7
2 - 512-KSA940TU_Q for q10
2 - 512-KSC2073TU for q9
2 - 512-KSC2310YBU for q11
**********************

is for BOTH AWH-048 boards

take this for example:
2 - 512-KSA940TU_Q for q10

There is ONE Q10 on EACH of two AWH-048 (left channel/side and right channel/side) thus you need TWO.

SOME of those transistors are no longer available (obsolete), like:
4 - 512-KSA910YBU for q5,q6
2 - 512-KSC2682YSTU




so this NEW list may help (from my notes)

Mouser parts numbers, a mix of Fairchild (512-) and ON-Semi (863-)

differential inputs, better off if the hfe is matched
Q1, Q2 2sa750 to-92 ecb 50v .05a .25w 100mhz hfe:450
four 512-KSA992FBU (ln)to-92 ecb 120v .05a .5w 100mhz 150-800hfe $0.05 ea

bias / vas
Q5, Q6 2sa858/ Q3, Q4 2sc1439 to-92 ecb 150v 0.5a .5w 100mhz hfe:150 four Q5, Q6 512-KSA1013YBU to-92L ecb 160v 1a .9w 50mhz 160-320hfe $0.17 (R=60-120, O=100/200, Y=160/320)
four Q3, Q4 512-KSC2383YBU to-92L ecb 160v 1a .9w 50mhz 160-320hfe $0.17
or
four Q5, Q6 512-KSA1381es x to-126 ecb 300v .1a 1.2/7w 150mhz 40-320hfe $0.27 ea
four Q3, Q4 512-KSC3503estu to-126 ecb 300v .1a 1.2/7w 150mhz 40-320hfe $0.28 ea



pre-driver
Q8 2sa899/ Q7 2sc1904 to-126 ecb 150v .05a 1w 100mhz hfe:150
two Q8 512-KSA1220AYS to-126 ecb 120/a160 1.2a 20w 155mhz 35-320hfe $0.39 (R=60-120, O=100/200, Y=160/320)
two Q7 512-KSC2690AYS to-126 ecb 120/a160 1.2a 20w 155mhz 35-320hfe $0.40
or:
two Q8 512-KSA1381es x to-126 ecb 300v .1a 1.2/7w 150mhz 40-320hfe $0.27 ea
two Q7 512-KSC3503estu to-126 ecb 300v .1a 1.2/7w 150mhz 40-320hfe $0.28 ea

-------------


drivers
Q10 2sb630/ Q9 2sd610 to-220 bce 200v 2a 25w 4mhz hfe:80
two Q10 512-KSA940TU_Q pnp to-220 bce 150v 1.5a 25w 4mhz 40-140hfe $0.54
two Q9 512-KSC2073TU npn to-220 bce 150v 1.5a 25w 4mhz 40-140hfe $0.54


power outputs (on the heat sinks on the outside of the case in the rear)
2sb600/2sd555 to-3 200v 10a 200w 14mhz hfe:70
four 863-MJ21194G to-3 NPN 250v 16A 250W 4mhz 8-75hfe $4.10
four 863-MJ21193G to-3 PNP 250v 16A 250W 4mhz 8-75hfe $4.10

overcurrent detector
Q11 2sc869 to-92 npn bce 50v 30mA .2w 150mhz hfe:35
two Q11 512-KSC2310OTA to-92 ecb 150v .05a .8w 100mhz 40-240hfe $0.11 ea



here's the insulators and thermal grease:
ten: 534-4662 to-3 mica insulators $0.16 each (two spares)
six: 534-4672 to-220 mica insulators $0.12 each
one: 532-249 1 oz thermal compound $4.71

two VR2 500 ohms single turn bias pot 652-3386H-1-501LF $1.60 ea
two VR1 500 ohms 12 turn offset pot 652-3266P-1-501LF $2.94 ea
or
two VR1 500 ohms 25 turn offset pot 652-3296P-1-501LF $2.94 ea


as for the capacitors:
two C11 0.22uf 50v 598-DSF050J224 $0.52 ea CDE Metallized Polyp
0.22uf 100v ecq 667-ECQ-V1224JM $0.35
four C15 C16 470uF/80v 647-UPW2A471MHD @ 1.92 ea nichicon pw - power filter 647-UHE2A471MHD6
two C2 10/16 647-UPW1C100MDD @ $0.13 ea nichicon upw - offset smoothing
two C5 220/16 647-UPW1C221MPD @ $0.28 ea nichicon upw - feedback integrator


at this point, there's not much left original....
I don't think we should worry about the diodes....

Plus I am going to look at the diodes, at $0.10 each, what the heck..
eight: 512-UF4004 $0.12 d6, d7, d10 & d11
four: 1s2471 512-1N4454 $0.03 d8, d9
two: 1s2473 512-1N4148 $0.03 D5
four: 1s1886 200v 1A, 512-UF4004 D3,D4


so we'll rehash the parts here, possibly yet today, coming up with the list including quantities... (ok?)


This is just so you can plan ahead.
There would be a few more parts for beefing up/renewing the protection circuits...
protection circuits... on awh-091 board
one: Q4, 512-KSD1616ALBU to-92 ecb 60v 1a 0.75w 160mhz 135-400hfe $0.09 current dump transistor
relay driver transistor and voltage regulator
two: Q5, Q6 (2sc1166 50v, .2a .6w) 512-KSC2690AYS to-126 ecb 120/a160 1.2a 20w 155mhz 35-320hfe $0.40
one: C4 100uf/16v (100/35) 647-UPW1V101MPD $0.15 protection circuit timing capacitor
one: C3 4.7uf/25v (4.7/50) 647-UPW1H4R7MDD $0.23 protection circuit ac power on signal integrator
two: C5,C6 100uf/50v (100/50) 647-UPW1H101MPD $0.50 protection circuit voltage regualtor
two: C1,C2 470uf/6v (470/16) 647-UPW1C471MPD $0.52 protection audio input caps


*******************

some extra stuff came along for the ride, from the notes...

The transistors are listed in complementary pairs, like q3 and q4 are electronic mirror images of q5 and q6
that may be what confused you, I hope....

if not, look at the schematic in the manual there will be a "Q11" which is a 2sc869.
look at the board layout and you will find q11 at the end of a row of four transistors that is next to a row of three transistors at one end of the board.
looking at theta transistor on the board you will see a c869 (they drop the "2 S").

don't know how much simpler I can do it...

 

[bdblkta]

Getting an error with these

512-KSA940TU_Q
512-KSC2310OTA

would this be the correct replacement for the first one?

512-KSA940TU

cant find anything recommended for the second.



Thanks again for all of your help Mark, I'm almost there. Once again I would ave been totally lost without your help. Josh

 

[markthefixer]

Getting an error with these

512-KSA940TU_Q
512-KSC2310OTA

would this be the correct replacement for the first one?

512-KSA940TU

cant find anything recommended for the second.



Thanks again for all of your help Mark, I'm almost there. Once again I would ave been totally lost without your help. Josh

just stop after the last number - unless there's an "A" after the number

thus ksa940
gets you a page that has 512-ksa940 as a full number.

also same for ksc2310
that yields 512-KSC2310YBU

both have few choices now...

I've said this many times before...

the data sheet reveals that Y and O are gain codes (R - O - Y)
and packaging codes BU for bulk and TA = plastic ammo magazine rail package are revealed in the specific pages accessed by the general page.

 

[bdblkta]

Alright one last issue four of the power outputs 863-MJ21194G are backordered so i wanted to see if there are any replacements that could be used? I did look but did not see any.

 

[anderslober]

MTF......I have copied and stored all your fantastic rebuild/transistor/cap info.

bdblkta........I have read the thread.......are you sure your ORIGINAL main outputs are blown? Have you checked the TR's according to the six-way test method? IF they aren't blown....it would be best to use these originals again.

Feel free to post some 'repair' pictures....that would be great.

 

[bdblkta]

Well today I finally put power to my 1250 again but have some issues.

As a follow up this has been completely recapped, all transistors replaced, new diodes, new relay, new thermal compound and bias and offset pots.
After powering up I went ahead with the offset and bias adjustments as per the manual.
VR1 and VR2 on the stabilizer board were adjusted to vr1 - 61.7 and vr2 - 62.3. This was as high as they would go, pots all the way clockwise.

VR1 on both amp boards went to 0.00v and VR2 on both amp boards went to +-100mv.

So here I am thinking everything is ok so i plug in my speakers wanting to hear my newly restored receiver sing. This was not the case. No output at all, nada, nothing. Tested multiple outputs still nothing.
I went ahead and pulled the jumpers to test the Pre and this does work and sound fine, all controls work as they should.

As I have been reading I have seen a post stating that when installing an ECB transistor into a location that had a BCE originally that the new transistor should be rotated 180(I guess this means looking at the blank side of the transistor to define the ECB layout). This I did not do as I had not seen this mentioned until today.

Please help my receiver sing in all of its glory..

Thanks, Josh

 

[bdblkta]

alright so now I have made it to the relay on the protection board and am not getting the relay to engage on that board. any help on where to go from there? Thanks

 

[anderslober]

ok......your Pre is working...that is good. You will have to go over your amp boards with a fine comb.....check all polarity of all caps, check polarity of diodes, and probably most important of all....check all your tr's.........including your main output tr's.
I found a very important mistake in the manual.....the sa628......it is BCE.......in the manual it says ECB.....If you put this tr in wrong.....I would imagine you wouldn't have output. EW or MTF will be along soon...............hang in there.

 

[markthefixer]

The replacement transistors MUST be installed according to their data sheets listings of which lead is the emitter, the base and the collector, the data sheets are available through the links on their mouser pages, although I DO list them as a courtesy. Lettering facing you , leads pointing down and going left to right is the standard orientation, then the ecb, bce or whatever is listed. The TO-220 power transistors have a metal tab making them very difficult to reverse when mounted correctly. almost all of the replacements I specify, that do NOT have the tab, are ecb.

you have to KNOW the EXACT lead arrangement on the transistor, and use the SYMBOL on the board to identify which lead goes where.

IF YOU ARE GOING TO REUSE AN ORIGINAL TRANSISTOR, YOU MUST PAY ATTENTION AND MARK DOWN (DRAW ETC) WHICH LEADS ARE WHAT USING THE SYMBOL ON THE BOARD WHERE IT WAS INSTALLED (AND WORKING) ORIGINALLY.

the manuals are frequently wrong.

this is from an old post:

First you need to learn about what the three transistor leads are about, and identifying which is which and where it goes according to the symbol. Then you will see that my parts list include lead arrangements - which assume the transistor lettering (and flat) are facing you and the leads are facing down, then go left to right.

The big TO-220's with the metal mounting plate are hard to reverse, but the smaller ones are, but my specified replacements are usually E C B as a rule of thumb BUT we ALWAYS CHECK...

But you really should start here and follow ALL the links...

http://www.audiokarma.org/forums/showthread.php?t=331932&page=5

DO YOU SEE these symbols on the boards you are working on?:

e is always the arrow on one angled line (direction can be out (npn) or in (pnp) towards the base)
b is always the flat line the other two lines come out if at an angle
c is always the angled line without the arrow

letters can be smudged or illegible, while the symbols are hard to mistake and pretty language independent
pioneer doesn't use letters, if there is a symbol. sometimes in a linear hole arrangement, there is only an 'e'.... with no room for a symbol.

PLEASE READ these links for transistor pictures and explanations, told quite informatively, with a LOT of stuff you need to have at least read:

to-92:http://en.wikipedia.org/wiki/TO92

to-220: http://en.wikipedia.org/wiki/TO220

plus if you can stand to wade through this:
http://en.wikipedia.org/wiki/Transistor

AT LEAST the first page or so, and the first picture,
what we are using is the bipolar junction transistor, or BJT
it will give you plenty of background....

AND - it just as it gets DEEP,
a section or so later it drops back to more understandable,
and drops some useful general information into your lap as a reward for sticking around.

This happens all the way to the end.

while you are working on the board, look for this / these circular (transistor) symbols, for later reference, notice how the circle is pierced by three lines (the leads) and the letters e b c near the piercings, and how the transistors are installed, if possible looking at their numbers and the ecb and bce arrangements I list for those numbers:

 

[bdblkta]

Thank you all for the help. I located one transistor on the protection board that had been installed incorrectly and now everything works. I do need to check bias, offset, etc. before I am done but it was late and I was able to test it for a minute.

 

[markthefixer]

:thmbsp:

 

[anderslober]

Great! Post a couple of pic's..............that would be great.

 

[bdblkta]

Still having this problem: VR1 and VR2 on the stabilizer board were adjusted to vr1 - 61.7 and vr2 - 62.3. This was as high as they would go, pots all the way clockwise.

also went to readjust vr1 on the amp boards. Tried to set them to full counter clockwise and they just keep spinning indefinetly. Had another pair available and they also just spin freely. I was very careful turning them but is it possible i broke them?

The reading on vr1 when tested as the manual states was around 80mv on both amp boards and turning the pot did nothing.

 

[anderslober]

yes...I think you may have broken them......time for some Bourns pots.

 

[bdblkta]

These are bourns