D.E.K
Loader
No go for Canada.
SX-1010 won't Power On...
- Thread starter D.E.K
- Start date
No go for Canada.
Just use the washer to hold it down.
What's going on with the replacement outputs?
What's going on with the replacement outputs?
D.E.K
Loader
I am going to order them from digikey either tomorrow or the next day, along with thermal compound and about 15 mica insulators. That's not the problem. The problem is, if there is a short elsewhere, I'll go through a few dozen of transistors. I don't know what went wrong in the first place when I used 2 transistors on each heatsink. I had sound at first and then boom.
Do the phrases "jumping the gun" and "turn down the bias" ring any bells?
Sure resembled thermal runaway and damage. Then keeping it on, and finally running sound through it was the coup de grace.
The ONLY objective of setting up the 2 outputs per channel - which was undiscussed - was to BRIEFLY see if the static amplifier conditions were balanced enough to allow the protection to kick in - thus revealing a lack of problems elsewhere in the amplifier's circuitry, had I had a chance to explain.
AFTER we checked things out with a BUNCH of measurements, and correctly set the bias for the existing transistors, a few watts at most would have been gingerly tried - for sound quality - with a HUGE list of things to watch out for and an immediate unconditional (and not repeated) shutdown IF anything on the list happened.
markthefixer said:
I can take some of the blame, for revealing the destination, while the journey needed much more explanation, and while I hoped that it would have a calming effect ("the light at the end of the tunnel") , it had the opposite.
AS it is, there is a LOT of damage to be checked for in the amps.
Since you haven't ordered the replacements yet, include these power amp transistors as well:
512-KSA992FBU (ln)to-92 ecb 120v .05a .5w 100mhz 150-800hfe $0.06 ea -- 10 each minimum
512-KSC1845EBU (ln)to-92 ecb 120v .05a .5w 100mhz 150-800hfe $0.06 ea -- 4 each minimum
512-KSA910YBU to-92 ecb 150v .05a .8w 100mhz 40-240hfe $0.12 ea -- 4 each minimum
512-KSC2310YBU to-92 ecb 150v .05a .8w 100mhz 40-240hfe $0.11 ea -- 12 each minimum
512-KSA1220AYS to-126 ecb 160 1.2a 20w 155mhz 35-320hfe $0.39 -- 4 each minimum
512-KSC2690AYS to-126 ecb 160 1.2a 20w 155mhz 35-320hfe $0.40 -- 2 each minimum
512-KSA940TU_Q pnp to-220 bce 150v 1.5a 25w 4mhz 40-140hfe $0.54 -- 2 each minimum
512-KSC2073TU npn to-220 bce 150v 1.5a 25w 4mhz 40-140hfe $0.54 -- 2 each minimum
This is enough (at the minimums) to do both power amps.
D.E.K
Loader
I assumed you tried with Digikey. Those are not Digikey's part #. That's why you couldn't find them.
Mark listed them as Mouser's part #: www.mouser.com
D.E.K
Loader
Yeah Digikey has all of them except the KSA940TU_Q. The part they have is KSA940TU and they seem to be 1.5W rather than 2.5W. The rest seem to be OK. You're not planning on making me solder those little things onto the little circuit board are you??? If you are... Well, I don't know about that.
KSA940TU is a lead free version of KSA940TU_Q. Electrically they're the same device.
If Mark says yes, it's more of your only choice, to do it or to not do it (to get it working or leave it dead). If the output destroyed something else in the amp board, those parts will have to be replaced or it may not work at all or it may destroy the new set of outputs then there goes another $40 of damages. But don't do it until Mark says so.
Edit: Forgot to say your 3rd choice is if you want it working but not comfortable to solder parts on boards, then you can send it to someone who can get it up and running. Keep in mind that you came this far doing good so far until you jumped too far.
So, Mark can get you up but you'll have to accept the challenges and restrain yourself if you decide to fix it yourself.
That's true. It is your receiver and your decision. The last thing I would want to do is force you to it(even IF I can).
If my previous post offended you, I apologize.
D.E.K
Loader
Not at all. No need. It's just that some things are being taken for granted here. "Get that part as well, while you're at it you might also replace this, solder that, solder this... " Shouldn't my point of view be taken into consideration for this job? How good I am at soldring? Most importantly, how good I am at de-soldering (never desoldered before for instance) Of course I want to try it and revive the unit. but... We're talking about 40 little transistors here. That is quite a task for a beginer.
I see where you're at. Well, have you considered maybe getting one of the smaller stereo like say SX-780 or smaller? My SX-780 is my current project coming this Saturday. I already ordered parts for it. I really needed it back next to my bed for sleeper. While making list of parts for the SX-780, it's MUCH simpler to work on compared to the SX-1010. The board is much more accessible top and bottom. Just remove the top cover and bottom cover and you'll have easy access to practice your desoldering and soldering skill and not having to remove any board. The SX-1010 is much more like a Jungle compared to this. That's the suggestion I have even many AK'ers would suggest the same to practice on smaller radio.
I would assume you're talking about the integrated amplifier. Sounds like a good idea. I would suggest that you may want to start a new thread for that because this thread is about SX-1010.
Hey, NO SWEAT, I'm just a friendly advisor. I won't get my nose out of joint if the path doesn't lead to a repair.
The enthusiasm you showed at the start was to me a good sign, things were going well overall, and when you "jumped the gun", it was just a signal to me to try to get you to not innovate as I steered you through the minefield.
The transistor list was for spares, which would cover the amps at a cost that would be less than or equal to the shipping costs. BUT it DOES assume soldering and desoldering (just about any troubleshooting thread does). I just didn't want a discouraging situation (for you) where we needed more parts, and something like "why didn't you tell me BEFORE I ordered the parts?" was said.
That said, if you are not comfortable desoldering and soldering, want to put it back together and pass the 1010 onto someone else, to get something that's working, no problem. I dislike (and really try to avoid) leaving people worse off than when they started.
Your choice of the 1010 ? Was it for the power ? I am going to PM you to ask things that shouldn't be asked in the forums.
As far as the soldering / desoldering, get something electronic (an old busted crt computer monitor? some mid line old tv etc) that somebody is tossing, and pull it apart, and practice removing and resoldering the components, and whatever you mess up at first, won't matter and you will gain valuable experience and confidence.
The enthusiasm you showed at the start was to me a good sign, things were going well overall, and when you "jumped the gun", it was just a signal to me to try to get you to not innovate as I steered you through the minefield.
The transistor list was for spares, which would cover the amps at a cost that would be less than or equal to the shipping costs. BUT it DOES assume soldering and desoldering (just about any troubleshooting thread does). I just didn't want a discouraging situation (for you) where we needed more parts, and something like "why didn't you tell me BEFORE I ordered the parts?" was said.
That said, if you are not comfortable desoldering and soldering, want to put it back together and pass the 1010 onto someone else, to get something that's working, no problem. I dislike (and really try to avoid) leaving people worse off than when they started.
Your choice of the 1010 ? Was it for the power ? I am going to PM you to ask things that shouldn't be asked in the forums.
As far as the soldering / desoldering, get something electronic (an old busted crt computer monitor? some mid line old tv etc) that somebody is tossing, and pull it apart, and practice removing and resoldering the components, and whatever you mess up at first, won't matter and you will gain valuable experience and confidence.
D.E.K
Loader
Don't think that your help and advice is not appreciated. It is, more than you know. Cheers.
In answer to a couple of PM's:
Desoldering can be accomplished by a regular iron and desoldering braid, a metal braid with chemicals that wicks up the solder from the joint. It's just that it is a continuing expense, as opposed to a one time expense for a tool of some type.
Or you can use a small squeeze bulb, but care must be taken not to press on the joint when it is hot, because the glue holding the foil is at it's weakest.
Then there is the spring loaded pump (one shot trigger) that instead of squeezing a bulb you hit the trigger after cocking it. It's a little more stable while you are using it. That's how I started out.
Then there is the radio shack iron with a squeeze bulb, a very economical alternative.
I do enough delicate desoldering that I have an old commercial station with a built in pump.
And, the STV-3 is the worst, most destructive place in the amp to have a failure, but the testing isn't hard to do, to be sure things are safe. After those tests, then the dim bulb tester saves us if there is something that gets by.
Yours should be fine, it's just a mounting ear (or both) that are a problem, solved by a washer.
You may get very very lucky and avoid soldering/desoldering IF it's only the outputs that were hurt.
I prefer to do all discussion on the forum, it's just that "commercial (trades too) posts are verboten in the forums, thus the PM.
Desoldering can be accomplished by a regular iron and desoldering braid, a metal braid with chemicals that wicks up the solder from the joint. It's just that it is a continuing expense, as opposed to a one time expense for a tool of some type.
Or you can use a small squeeze bulb, but care must be taken not to press on the joint when it is hot, because the glue holding the foil is at it's weakest.
Then there is the spring loaded pump (one shot trigger) that instead of squeezing a bulb you hit the trigger after cocking it. It's a little more stable while you are using it. That's how I started out.
Then there is the radio shack iron with a squeeze bulb, a very economical alternative.
I do enough delicate desoldering that I have an old commercial station with a built in pump.
And, the STV-3 is the worst, most destructive place in the amp to have a failure, but the testing isn't hard to do, to be sure things are safe. After those tests, then the dim bulb tester saves us if there is something that gets by.
Yours should be fine, it's just a mounting ear (or both) that are a problem, solved by a washer.
You may get very very lucky and avoid soldering/desoldering IF it's only the outputs that were hurt.
I prefer to do all discussion on the forum, it's just that "commercial (trades too) posts are verboten in the forums, thus the PM.
D.E.K
Loader
Something like this:
http://www.thesource.ca/estore/Prod...line&category=Soldering+Tools&product=6412200
http://www.thesource.ca/estore/Prod...line&category=Soldering+Tools&product=6412200