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SX-1010 won't Power On...

Cheers Chris. Came this far achieving power on without fireworks and smoke festival, might as well continue. I once again would like to express my appreciation for the help you guys have given, especially Mark who is the head honcho of this operation. Worst case scenario I'll end up with a 40 lbs boat anchor or a hole in the wall the size of an SX-1010 which won't make me feel any worse and frustrated than I am right now. But first the braid. I am NOT using the bulb or the vacuum for desoldering. In the meantime I will take the bottom plate off and do a visual inspection of the soldering on the power supply board, especially the 12 and 30V regulator transistors (thanks to jpdylon and ccheath for pointing that out) I will sure as crap replace that half-arse BIAS diode too, many thanks to Echo for his kind offer. :thmbsp:
 
Ok, the fiddling with the controls to maintain sound is taken care of by deoxiting and faderlubing all the switches and controls.

As for the sound, you say it fades away to zero on both channels,
then slowly comes back, then fades all over again.

when does the relay click out, when the sound is fading out?

and then if you turn it off for 5 - 10 minutes and things work ok.

And this happens regardless of if you are listening to FM or the computer audio?

When it drops out, try firmly whacking the side of the unit with your hand and see if it makes a difference.
 
it's really hard to say when the relay is clicking out. The volume fading happened only once and that is when the relay stopped engaging.

Yes, relay clicks out regardless of FM or computer audio. I would try to observe more but the relay seems to click in less and less now.
 
First step is the replacement of capacitors, some transistors, and the addition of a diode, all on the protection board.

BUT, that may NOT (40% chance?) be the cure - while it WILL assure the relaibility of the protection circuit. Then if necessary we can continue deeper into the unit.

The postage for the parts will be more than the cost of the parts themselves.

Game?

Study the manual so you can tell ME where the protection board is, the first steps toward understanding...

Then I will walk you through the replacements when the parts (parts #'s to be provided by me) are in.
 
Found the protection board circuit assembly and foil side. The protection circuit is located next to the power transformer, bottom view. I didn't pin point on the actual unit yet but I don't think that will be a problem.

There are 6 Capacitors, 7 Transistors and 1 Diode you mentioned. That is 14 pieces I am going to de-solder and solder back correct? Boy that's some task, for me anyway. I feel that I should take it on. I am stuck with this unit anyway, the blood is on my hands. How about you? What are your impressions/expectations? Do YOU think that I should go ahead? If say I screwed it up, HOW BAD could the damage be?
 
D.E.K said:
Found the protection board circuit assembly and foil side. The protection circuit is located next to the power transformer, bottom view. I didn't pin point on the actual unit yet but I don't think that will be a problem.

There are 6 Capacitors, 7 Transistors and 1 Diode you mentioned. That is 14 pieces I am going to de-solder and solder back correct? Boy that's some task, for me anyway. I feel that I should take it on. I am stuck with this unit anyway, the blood is on my hands. How about you? What are your impressions/expectations? Do YOU think that I should go ahead? If say I screwed it up, HOW BAD could the damage be?
Click to expand...

Not all the parts need to be replaced, I'll have a list up in 24 hours or less so you can order them. Directions (detailed) will come later, but before the parts arrive. There actually are threads on this in the forum.

If you can take pictures of the board, and send them to me - I can mark them up and send them back as guides. Eventually I will PM you my email address.
 
None of those are any of my concern, AT THE MOMENT. I still want to know what you think. What are the odds of me hacking it? You guided me through replacing the output transistors. Didn't turn out very well but the receiver powers up and I am pretty sure the output transistors are in working order. Obviously what I'm going to try to accomplish is MUCH harder. Just so you know that I am aware of it. Yes, there is a list of parts in this forum:

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
 
D.E.K said:
None of those are any of my concern, AT THE MOMENT. I still want to know what you think. What are the odds of me hacking it? You guided me through replacing the output transistors. Didn't turn out very well but the receiver powers up and I am pretty sure the output transistors are in working order. Obviously what I'm going to try to accomplish is MUCH harder. Just so you know that I am aware of it. Yes, there is a list of parts in this forum:

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
Click to expand...

YOU DID get SOUND. AND the thing came to you BROKEN - that's PROGRESS.

And one of the more demanding procedures is mounting the power transistors - which you accomplished.

Those are the parts for the amplifier, there are completely different parts for the protection circuit.

The protection circuit board is simpler than the amplifier circuit board. The spacings between traces are wide enough that neophyte solderers will be somewhat protected from shorting two traces accidentally with solder (solder bridges). I gave you 60/40 odds that it is that board. Screwing up on that board is far less likely to generate widespread damage than the amplifier.

I'm sorry, I'm not good at pep talks.... I won't talk you into it, but I will talk you through it. YOU have to make the decision whether to fix it, ship it to someone else to fix it or sell it as is.
 
Fascinating thread!

A long-stored SX-1010 was given to me by the original owner some time ago. I was assured it was working. Physically, the unit needed cleanup, but was in pretty stellar condition beneath the grime. Fresh tung oil on the cabinet, and it's beautiful! Before powering it up, I took the bonnets off and was alarmed by how toasted the Power Supply board in the unit's underbelly (AWR-054-A) was. Some of the cap covers were shrunk and the board had a good suntan. So I replaced all the electrolytics on the Power Supply board, and while I was at it, I replaced the 'lytics on the topside Power Supply board (AWR-053-A), and since I had a bunch of Panasonic FCs, I did the Equalizer Amp board and the Control Amp board, too. My main 18,000uF power supply caps look good, no leaks or swelling, but I put a 680uf 63V Panasonic FC across the terminals - something I saw done on an old Sansui.

I powered up the unit and set the bias - though the manual says to connect 8 ohm resistors across the speaker terminals when setting the bias, so I did so. Both channels were at about 35 mV. Everything seemed a go, relays clicked, etc. so I hooked it up to speakers. I have full stereo, but a little THHHH occasionally in the lower frequencies. The sound did not seem to have the openness of soundstage that I was expecting from experience with my old Marantz 2270. Worse, on AM & FM, I have very faint - all but inaudible - staticky sound on the left channel (unless I depress the Mono switch, which would be ok for AM, but helps me not on FM). Disappointed! So now I'm studying the schematic to troubleshoot the tuner section, but I'm also wondering if there may still be some sunburn to be repaired on the underbelly Power Supply board? Any suggestions?
 
LWB said:
Fascinating thread!

A long-stored SX-1010 was given to me by the original owner some time ago. I was assured it was working. Physically, the unit needed cleanup, but was in pretty stellar condition beneath the grime. Fresh tung oil on the cabinet, and it's beautiful! Before powering it up, I took the bonnets off and was alarmed by how toasted the Power Supply board in the unit's underbelly (AWR-054-A) was. Some of the cap covers were shrunk and the board had a good suntan. So I replaced all the electrolytics on the Power Supply board, and while I was at it, I replaced the 'lytics on the topside Power Supply board (AWR-053-A), and since I had a bunch of Panasonic FCs, I did the Equalizer Amp board and the Control Amp board, too. My main 18,000uF power supply caps look good, no leaks or swelling, but I put a 680uf 63V Panasonic FC across the terminals - something I saw done on an old Sansui.

I powered up the unit and set the bias - though the manual says to connect 8 ohm resistors across the speaker terminals when setting the bias, so I did so. Both channels were at about 35 mV. Everything seemed a go, relays clicked, etc. so I hooked it up to speakers. I have full stereo, but a little THHHH occasionally in the lower frequencies. The sound did not seem to have the openness of soundstage that I was expecting from experience with my old Marantz 2270. Worse, on AM & FM, I have very faint - all but inaudible - staticky sound on the left channel (unless I depress the Mono switch, which would be ok for AM, but helps me not on FM). Disappointed! So now I'm studying the schematic to troubleshoot the tuner section, but I'm also wondering if there may still be some sunburn to be repaired on the underbelly Power Supply board? Any suggestions?
Click to expand...

Yes, as an AK member you are fully able to, and welcome to start your own thread...

At which time I will be glad to address your points.
 
Probably should start another thread, but get some Caigs Deoxit 5 and clean every control, pushbuttons and rotary. Then put some Caigs faderlube on tone, volume , and balance controls.
 
sx-1010 AWM062

You can order these from mouser.com:
two:Q6, Q7 522-ZTX1056A $1.51 ea NPN TO-92E ebc 150v 3a 1w (Vce(sat)=0.3v @ 3a) 120mhz 30-1200 hfe relay driver transistor
one: C6 100uf/16v (100/35) 647-UPW1V101MPD $0.15 protection circuit timing capacitor
one: C5 4.7uf/25v (4.7/50) 647-UPW1H4R7MDD $0.23 protection circuit ac power on signal integrator
two: C1, C2 0.22uf /10v (0.22uf/50v) 598-DSF050J224 $0.50 ea over-current integrators. polyester film capacitors!!!
two: C3, C4 330uf/25v (330/25) 647-UPW1E331MPD $0.51 ea
one: new part 512-1n4004 conventional rectifier 1a 400v $0.06 ea

The other transistors (Q1-Q5) in the protection circuit won't need changing. You are ADDING the 1n4004 diode to prevent what has already happened to you from happening again, every time the relay turns off, the magnetic field's energy has to go somewhere, so it makes a negative voltage pulse that destroys a little bit of the Q7 junction every time, the diode shunts this energy away from the transistor, at the cost of a few MILLISECONDS more time for the relay to disengage...
Pioneer did the diode thing on newer and higher end models as part of the design later on.

Don't worry, I'll be talking you through it.

The best advice I can give on soldering is to practice, get a junked piece of electronics from the curb, pull out a circuit board and practice removing and reinstalling the small parts. Sure, you'll lift pads & cause damage at first, BUT that's on a piece of junk we don't care about!!
 
I ordered this same list yesterday. The 4.7's were on back order. So, I just changed them to 100 volt to get it all at the same time. Have no idea how long they will be out but they are the same size and the price difference is negligible. Part number 647-UPW2A4R7MDD
 
 
Those numbers are EXACT -

the one number 647-UPW1H4R7MDD is ON ORDER

so use 647-UPW2A4R7MDD as ZeroJunk has posted.

comparing the two:

647-UPW1H4R7MDD
647-UPW2A4R7MDD

you can see that one has a 1H (50 volts) while the other has a 2A (100 volts).

IF the mouser search engine comes up with multiple parts numbers that have MORE numbers or letters after what I have specified -IGNORE IT - just get the numbers I listed with the ONE EXCEPTION of that is explained above.
 
Sorry, I took the last 2 4.7uf 50v they had in my last order. :D I tried getting 8 but forget the double shipping charge.
 
Mark, here's the the order which will be placed tomorrow or coming up Monday the latest:

522-ZTX1056A
(Quantity:3)

647-UPW1V101MPD
(Quantity:2)

647-UPW2A4R7MDD
(Quantity: 2)

598-DSF050J224
(Quantity: 3)

647-UPW1E331MPD
(Quantity: 3)

512-1N4004
(Quantity: 2)

512-KSA992FBU
(Quantity: 11)

512-KSC1845EBU
(Quantity: 5)

512-KSA910YSHTA
(Quantity: 5)

512-KSC2310YBU
(Quantity: 13)

512-KSA1220AYS
(Quantity: 5)

512-KSC2690AYS
(Quantity: 3)

512-KSA940TU_Q
(Quantity: 3)

512-KSC2073TU
(Quantity: 3)



As you can see, I am going to order the parts needed for the Power Amplifier section too. I don't want to pay double shipping in case I can successfuly replace the Power Protection and decide to do the Power Amp as well. Also, you will notice that I added +1 for EACH item considering I might, and possibly will, damage some of them. I will go ahead with this unless you have an objection to the +1 spares.
 
D.E.K said:
Mark, here's the the order which will be placed tomorrow or coming up Monday the latest:

522-ZTX1056A
(Quantity:3)

647-UPW1V101MPD
(Quantity:2)

647-UPW2A4R7MDD
(Quantity: 2)

598-DSF050J224
(Quantity: 3)

647-UPW1E331MPD
(Quantity: 3) ********* get five , two for the power amp

512-1N4004
(Quantity: 2)

512-KSA992FBU
(Quantity: 11)

512-KSC1845EBU
(Quantity: 5)

512-KSA910YSHTA
(Quantity: 5)

512-KSC2310YBU
(Quantity: 13)

512-KSA1220AYS
(Quantity: 5)

512-KSC2690AYS
(Quantity: 3)

512-KSA940TU_Q
(Quantity: 3)

512-KSC2073TU
(Quantity: 3)



As you can see, I am going to order the parts needed for the Power Amplifier section too. I don't want to pay double shipping in case I can successfuly replace the Power Protection and decide to do the Power Amp as well. Also, you will notice that I added +1 for EACH item considering I might, and possibly will, damage some of them. I will go ahead with this unless you have an objection to the +1 spares.
Click to expand...

add:
647-UPW1V100MDD ($0.11 ea)
(quantity:3) ****** two for the power amp


5989-100V.68-F (0.67 each)
(quantity:3) ***** two for the power amp

I have checked the stock and prices on these.


Since you are getting the transistors for the power amp, might as well get the 6 caps. (not 8 as schematic says, actual experience dictates just 6 are actually there).
 
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