My SA - 7100 Drops in and out of Protection

I've been sitting on this for a while now and I have searched this forum for similar issues and none have really nailed the exact symptoms for mine.
I don't have anything connected to it except power. I power it up and after, say, 3 minutes it will go into protection. So I leave it powered up for a good 30 minutes to watch its habit.
It will sometimes flicker the protection in quick succession , then it will stay on, then it will reset, then on and off... and on it goes.
I realise it's old and may require refurbishment, but if someone can point this novice in the right direction, I would greatly appreciate your help. I'm not an electronics tech but I would like to have a go at it. Please be patient with me.

The last picture tells the tale, the amplifier has four transistors with yellow dots, they are 2sa726's and are problematic.
Then there are those 2sc1451 transistors, REALLY bad news. They are the round silvery metal cans very close to the yellow dot transistors.
Then there are 2sa725 transistors in the phono amp and 2sa726's in the board connected to the front panel controls.

ALL need to be replaced, we can provide parts lists and sources.

There is other stuff in there to do while it's open and easily accessible. Get it all done, and you won't need to do anything but listen (and an occasional cleaning/deoxiting) for years and years

markthefixer said:

The last picture tells the tale, the amplifier has four transistors with yellow dots, they are 2sa726's and are problematic.
Then there are those 2sc1451 transistors, REALLY bad news. They are the round silvery metal cans very close to the yellow dot transistors.
Then there are 2sa725 transistors in the phono amp and 2sa726's in the board connected to the front panel controls.

ALL need to be replaced, we can provide parts lists and sources.

There is other stuff in there to do while it's open and easily accessible. Get it all done, and you won't need to do anything but listen (and an occasional cleaning/deoxiting) for years and years

Click to expand...

I have no problem with replacing anything you think I need to. Let me know what else I can do while i'm in there. I have no problem with paying extra for the good stuff either, if you can recommend higher quality than standard to make it a better sounding amp, i'm up for it too.
I would be greatful if you could provide the exact part numbers/quantities etc, I'm thinking Mouser, I do believe they ship to Australia.
Sorry for this dumb question But you mentioned the 2sa725 transistors in the phono amp and 2sa726's in the board connected to the front panel controls..
By looking at Pic 1(the one showing the entire layout), which board is which ?
The Amplifier board being the one at the back of course, just the other 2 I'm not sure of.
Thanks for your advice Mark. I had a feeling you'd nail this for me !

You need to get the service manual, (4m download)

The service manual has to be read, every page - as it is the road map to finding components, and I use it's nomenclature to identify parts.

I'm pretty jammed up right now, so it will take a little while to get it together.

No problem, whenever your ready.
Thanks again !

bump

Please see my SA-7100 rebuild that came out fantastic, thanks to input from MTF. If you need any Mouser numbers or what ever let me know.


http://www.audiokarma.org/forums/showthread.php?t=503150

patfont said:

Please see my SA-7100 rebuild that came out fantastic, thanks to input from MTF. If you need any Mouser numbers or what ever let me know.


http://www.audiokarma.org/forums/showthread.php?t=503150

Click to expand...

Thanks alot, I am currently putting together a spread sheet covering all the caps and transistors required for a refurb. After many many hours of sifting through threads and post, especially yours I have compiled a pretty decent list so far. I will share this when it's done.
I will need your help though when it comes to the Mouser part numbers. I tried to search their website and failed dismally as I am not familiar with the technical jargon when completing advanced searches. Am I able to send you a copy of the "excel" spread somehow to look over it for me ?
***Also, I came across something strange today whilst cataloging the caps on the EQUALISER AMP. AWF-005-0. According to the schematic there are two extra caps. I'm not sure which ones to certify as I am showing the two larger caps as being 330uf/16v and the two smaller ones in between as 100uf/10v.
The larger ones most likely being c13 and c14. According to the locality of the two on the schematic they don't match those from the ones pictured.?? Which is what ? and why do I have 330uf/16v on my board and the schematic is showing 220uf/16 ? :scratch2:

Awesomeaudio said:

Thanks alot, I am currently putting together a spread sheet covering all the caps and transistors required for a refurb. After many many hours of sifting through threads and post, especially yours I have compiled a pretty decent list so far. I will share this when it's done.
I will need your help though when it comes to the Mouser part numbers. I tried to search their website and failed dismally as I am not familiar with the technical jargon when completing advanced searches. Am I able to send you a copy of the "excel" spread somehow to look over it for me ?
***Also, I came across something strange today whilst cataloging the caps on the EQUALISER AMP. AWF-005-0. According to the schematic there are two extra caps. I'm not sure which ones to certify as I am showing the two larger caps as being 330uf/16v and the two smaller ones in between as 100uf/10v.
The larger ones most likely being c13 and c14. According to the locality of the two on the schematic they don't match those from the ones pictured.?? Which is what ? and why do I have 330uf/16v on my board and the schematic is showing 220uf/16 ? :scratch2:

Click to expand...

On my board and on your board and on the schematic are 330uf 16V, so replace with 330uf 16V, thats what I did. Mine did not have the 2 extra caps either, there are 10 e-caps to replace on that board.

PM me your email if you want, mouser allows you to share my orders with you.

Awesomeaudio said:

I have no problem with replacing anything you think I need to. Let me know what else I can do while i'm in there. I have no problem with paying extra for the good stuff either, if you can recommend higher quality than standard to make it a better sounding amp, i'm up for it too.
I would be greatful if you could provide the exact part numbers/quantities etc, I'm thinking Mouser, I do believe they ship to Australia.
Sorry for this dumb question But you mentioned the 2sa725 transistors in the phono amp and 2sa726's in the board connected to the front panel controls..
By looking at Pic 1(the one showing the entire layout), which board is which ?
The Amplifier board being the one at the back of course, just the other 2 I'm not sure of.
Thanks for your advice Mark. I had a feeling you'd nail this for me !

Click to expand...

Hi there. Don't buy through Mouser to get them to Aus. X-On is the local distributer here for them. http://www.x-on.com.au/Results.aspx?srchVal=KSC3503DSTU If its under $200, you'll be charged $15 delivery so I'd advise to order plenty of spares for a rainy day. It'll reduce their overall cost as well. RS Australia also have a massive selection of components and have free delivery no matter how small an order. I've ordered a bag of 5 ecaps ($1.20) and thet delivered to my door.

Anyway, from one Aussie rookie to another - Good luck with your project:thmbsp:

Post up a list when you get it done and I'll add this thread to the recap list thread I started! :thmbsp:

patfont said:

On my board and on your board and on the schematic are 330uf 16V, so replace with 330uf 16V, thats what I did. Mine did not have the 2 extra caps either, there are 10 e-caps to replace on that board.

PM me your email if you want, mouser allows you to share my orders with you.

Click to expand...

Thanks for the input. I'll replace the caps on the board as I see them. Not sure which schematic you have, but the one I have shows 220uf/16v for the 330/16v.
Apparently, another member has just informed me that mouser has a local distributor here. We can still collaborate on the the part numbers and complete the spread sheet so others can use it.:thmbsp:

patfont said:

On my board and on your board and on the schematic are 330uf 16V, so replace with 330uf 16V, thats what I did. Mine did not have the 2 extra caps either, there are 10 e-caps to replace on that board.

PM me your email if you want, mouser allows you to share my orders with you.

Click to expand...

mallynoshow said:

Hi there. Don't buy through Mouser to get them to Aus. X-On is the local distributer here for them. http://www.x-on.com.au/Results.aspx?srchVal=KSC3503DSTU If its under $200, you'll be charged $15 delivery so I'd advise to order plenty of spares for a rainy day. It'll reduce their overall cost as well. RS Australia also have a massive selection of components and have free delivery no matter how small an order. I've ordered a bag of 5 ecaps ($1.20) and thet delivered to my door.

Anyway, from one Aussie rookie to another - Good luck with your project:thmbsp:

Click to expand...

Hey mate, thanks for your valuable info ! Good too know you're there. I had no idea X-on existed and right under my nose too at Newington. I thought Jaycar had no opposition here.
Do the two you mention use the Mouser part numbers ?
I'm really looking forward to this project, and once I have all the bits in my possession It's full steam ahead !
P.S. Are you in Sydney too ?
Cheers mate

Marty said:

Post up a list when you get it done and I'll add this thread to the recap list thread I started! :thmbsp:

Click to expand...

No problem. I'll be happy to share.

I AM working on a list, here's the spreadsheet so far:
phono amp
awf-005 c1 1 25 cssa 1 50 647-UKL1H010KDDANA
awf-005 c2 1 25 cssa 1 50 647-UKL1H010KDDANA
awf-005 c3 100 35 cea 100 35 647-UPW1V101MPD
awf-005 c4 100 35 cea 100 35 647-UPW1V101MPD
awf-005 c8 47 35 cea 47 35 647-UPW1V470MED
awf-005 c10 47 35 cea 47 35 647-UPW1V470MED
awf-005 c11 10 16 cea 10 50 647-UPW1H100MDD
awf-005 c12 10 16 cea 10 50 647-UPW1H100MDD
awf-005 c13 220 16 cea 220 35 647-UPW1V221MPD
awf-005 c14 220 16 cea 220 35 647-UPW1V221MPD
awf-005 c17 10 25 cssa 10 50 647-UKL1H100KDDANA
awf-005 c18 10 25 cssa 10 50 647-UKL1H100KDDANA
awf-005 q1 2sa725 512-KSA992FBU
awf-005 q2 2sa725 512-KSA992FBU
awf-005 q3 2sc1313 512-KSC1845FTA
awf-005 q4 2sc1313 512-KSC1845FTA
awf-005 q5 2sc1313 512-KSC1845FTA
awf-005 q6 2sc1313 512-KSC1845FTA


control amp
awg-016 c3 47 50 cea 47 50 647-UPW1H470MED
awg-016 c4 47 50 cea 47 50 647-UPW1H470MED
awg-016 c7 10 25 cea 10 50 647-UPW1H100MDD
awg-016 c8 10 25 cea 10 50 647-UPW1H100MDD
awg-016 c13 47 10 cea 47 25 647-UPW1E470MDD
awg-016 c14 47 10 cea 47 25 647-UPW1E470MDD
awg-016 c15 4.7 25 cea 4.7 50 647-UPW1H4R7MDD
awg-016 c16 4.7 25 cea 4.7 50 647-UPW1H4R7MDD
awg-016 c17 2.2 25 cssa 2.2 50 647-UKL1H2R2MDDANA
awg-016 c18 2.2 25 cssa 2.2 50 647-UKL1H2R2MDDANA
awg-016 c29 10 25 cea 10 50 647-UPW1H100MDD
awg-016 c30 10 25 cea 10 50 647-UPW1H100MDD
awg-016 c31 10 25 cea 10 50 647-UPW1H100MDD
awg-016 c32 10 25 cea 10 50 647-UPW1H100MDD
awg-016 c35 100 6 cea 100 10 647-UPW1A101MDD
awg-016 c36 100 6 cea 100 10 647-UPW1A101MDD
awg-016 c37 47 50 cea 47 50 647-UPW1H470MED
awg-016 c38 47 50 cea 47 50 647-UPW1H470MED
awg-016 c39 2.2 25 cssa 2.2 50 647-UKL1H2R2MDDANA
awg-016 c40 2.2 25 cssa 2.2 50 647-UKL1H2R2MDDANA
awg-016 q3 2sa725 512-KSA992FBU
awg-016 q4 2sa725 512-KSA992FBU
awg-016 q5 2sc1313 512-KSC1845FTA
awg-016 q6 2sc1313 512-KSC1845FTA

power supply
awr-026 c1 220 50 cea 220 50 647-UPW1H221MPD6
awr-026 c2 100 50 cea 100 50 647-UPW1H101MPD
awr-026 c4 100 35 cea 100 35 647-UPW1V101MPD
awr-026 c5 220 35 cea 220 35 647-UPW1V221MPD
awr-026 c10 220 50 cea 220 50 647-UPW1H221MPD6
awr-026 c11 220 50 cea 220 50 647-UPW1H221MPD6
awr-026 q1 2sd313 512-KSC2073TU
awr-026 q2 2sc945 512-KSC2383YTA
awr-026 d1 sib01-02 400 1a 512-1n4004
awr-026 d2 sib01-02 400 1a 512-1n4004
awr-026 d3 wz-130 13v zener 500mW 512-1N5243B
awr-026 d4 ds-118 400 3a 400 3a 512-1N5404
awr-026 d5 ds-118 400 3a 400 3a 512-1N5404
awr-026 d6 ds-118 400 3a 400 3a 512-1N5404
awr-026 d7 ds-118 400 3a 400 3a 512-1N5404


protection
awm-027 c3 330 6 cea 330 10 647-UPW1A331MPD
awm-027 c4 330 6 cea 330 10 647-UPW1A331MPD
awm-027 c5 4.7 25 cea 4.7 50 647-UPW1H4R7MDD
awm-027 c6 100 16 cea 100 35 647-UPW1V101MPD
awm-027 q1 2sc857 512-KSC1845FTA
awm-027 q2 2sc857 512-KSC1845FTA
awm-027 q3 2sc945 512-KSC1845FTA
awm-027 q4 2sc945 512-KSC1845FTA
awm-027 q5 2sa733 512-KSA992FBU
awm-027 q6 2sc945 512-KSC2383YTA
awm-027 q7 2sc1384 512-KSC2690AYS
awm-027 d1 1s2472 512-1n4148
awm-027 d2 1s2472 512-1n4148
awm-027 d3 1s2472 512-1n4148
awm-027 d4 1s2472 512-1n4148
awm-027 d5 1s2472 512-1n4148
awm-027 d6 1s2473 512-1n4148
awm-027 d7 1s2473 512-1n4148
awm-027 d8 1s2473 512-1n4004


power amp
awh-021 c1 0.47 25 cssa 0.47 50 598-DSF050J474
awh-021 c2 0.47 25 cssa 0.47 50 598-DSF050J474
awh-021 c3 0.47 25 cssa 0.47 50 598-DSF050J474
awh-021 c4 0.47 25 cssa 0.47 50 598-DSF050J474
awh-021 c5 1.5 25 cea 1.5 50 647-UKL1H1R5MDD1TA
awh-021 c6 1.5 25 cea 1.5 50 647-UKL1H1R5MDD1TA
awh-021 c11 330 10 cea 330 10 647-UPW1A331MPD
awh-021 c12 330 10 cea 330 10 647-UPW1A331MPD
awh-021 c13 100 50 cea 100 50 647-UPW1H101MPD
awh-021 c14 100 50 cea 100 50 647-UPW1H101MPD
awh-021 c23 470 35 cea 470 35 647-UPW1V471MPD
awh-021 c24 470 35 cea 470 35 647-UPW1V471MPD
awh-021 c25 22 10 cea 22 10 647-UPW1A220MDD
awh-021 c26 22 10 cea 22 10 647-UPW1A220MDD
awh-021 vr1 4.7k 25t 652-3296P-1-502LF
awh-021 vr2 4.7k 25t 652-3296P-1-502LF
awh-021 vr3 100 ohms 652-3386H-1-101LF
awh-021 vr4 100 ohms 652-3386H-1-101LF
awh-021 q1 2sa726 512-KSA992FBU
awh-021 q2 2sa726 512-KSA992FBU
awh-021 q3 2sa726 512-KSA992FBU
awh-021 q4 2sa726 512-KSA992FBU
awh-021 q5 2sc1451 512-KSC3503dstu
awh-021 q6 2sc1451 512-KSC3503dstu
awh-021 q7 2sd356 to-126 10w 512-KSC2690AYS
awh-021 q8 2sd356 to-126 10w 512-KSC2690AYS
awh-021 q9 2sb526 to-126 10w 512-KSA1220AYS
awh-021 q10 2sb526 to-126 10w 512-KSA1220AYS
awh-021 q11 2sd371 npn to-3 863-MJ21194G
awh-021 q12 2sd371 npn to-3 863-MJ21194G
awh-021 q13 2sb531 pnp to-3 863-MJ21193G
awh-021 q14 2sb531 pnp to-3 863-MJ21193G
awh-021 d1 wz-130 13v zener 500mW 512-1N5243B
awh-021 d2 wz-130 13v zener 500mW 512-1N5243B
awh-021 d3 stv-4
awh-021 d4 stv-4
awh-021 d5 1s2473 512-1n4148
awh-021 d6 1s2473 512-1n4148
awh-021 d7 1s2473 512-1n4148


this is getting closer to the final thing - there ARE parts that are unnecessary (some inexpensive, and a few expensive ones like ~16.00 for q11-q14 outputs)

parts list of EVERYTHING, for mouser parts list importer:

647-UKL1H010KDDANA
647-UKL1H010KDDANA
647-UPW1V101MPD
647-UPW1V101MPD
647-UPW1V470MED
647-UPW1V470MED
647-UPW1H100MDD
647-UPW1H100MDD
647-UPW1V221MPD
647-UPW1V221MPD
647-UKL1H100KDDANA
647-UKL1H100KDDANA
512-KSA992FBU
512-KSA992FBU
512-KSC1845FTA
512-KSC1845FTA
512-KSC1845FTA
512-KSC1845FTA



647-UPW1H470MED
647-UPW1H470MED
647-UPW1H100MDD
647-UPW1H100MDD
647-UPW1E470MDD
647-UPW1E470MDD
647-UPW1H4R7MDD
647-UPW1H4R7MDD
647-UKL1H2R2MDDANA
647-UKL1H2R2MDDANA
647-UPW1H100MDD
647-UPW1H100MDD
647-UPW1H100MDD
647-UPW1H100MDD
647-UPW1A101MDD
647-UPW1A101MDD
647-UPW1H470MED
647-UPW1H470MED
647-UKL1H2R2MDDANA
647-UKL1H2R2MDDANA
512-KSA992FBU
512-KSA992FBU
512-KSC1845FTA
512-KSC1845FTA


647-UPW1H221MPD6
647-UPW1H101MPD
647-UPW1V101MPD
647-UPW1V221MPD
647-UPW1H221MPD6
647-UPW1H221MPD6
512-KSC2073TU
512-KSC2383YTA
512-1n4004
512-1n4004
512-1N5243B
512-1N5404
512-1N5404
512-1N5404
512-1N5404



647-UPW1A331MPD
647-UPW1A331MPD
647-UPW1H4R7MDD
647-UPW1V101MPD
512-KSC1845FTA
512-KSC1845FTA
512-KSC1845FTA
512-KSC1845FTA
512-KSA992FBU
512-KSC2383YTA
512-KSC2690AYS
512-1n4148
512-1n4148
512-1n4148
512-1n4148
512-1n4148
512-1n4148
512-1n4148
512-1n4004



598-DSF050J474
598-DSF050J474
598-DSF050J474
598-DSF050J474
647-UKL1H1R5MDD1TA
647-UKL1H1R5MDD1TA
647-UPW1A331MPD
647-UPW1A331MPD
647-UPW1H101MPD
647-UPW1H101MPD
647-UPW1V471MPD
647-UPW1V471MPD
647-UPW1A220MDD
647-UPW1A220MDD
652-3296P-1-502LF
652-3296P-1-502LF
652-3386H-1-101LF
652-3386H-1-101LF
512-KSA992FBU
512-KSA992FBU
512-KSA992FBU
512-KSA992FBU
512-KSC3503dstu
512-KSC3503dstu
512-KSC2690AYS
512-KSC2690AYS
512-KSA1220AYS
512-KSA1220AYS
863-MJ21194G
863-MJ21194G
863-MJ21193G
863-MJ21193G
512-1N5243B
512-1N5243B


512-1n4148
512-1n4148
512-1n4148

Awesomeaudio said:

Hey mate, thanks for your valuable info ! Good too know you're there. I had no idea X-on existed and right under my nose too at Newington. I thought Jaycar had no opposition here.
Do the two you mention use the Mouser part numbers ?
I'm really looking forward to this project, and once I have all the bits in my possession It's full steam ahead !
P.S. Are you in Sydney too ?
Cheers mate

Click to expand...

Hey maaaaaaaaaaaaate

X-On uses the same mouser numbers so it'll be easy. RS is great if you know the specs, or you can use a component matcher and then cross reference on what you need. This one for example http://www.fairchildsemi.com/crossref/crossrefSearch.do

BTW, I'm in Melbourne or for our Sepo friends, Mel-born

mallynoshow said:

Hey maaaaaaaaaaaaate

X-On uses the same mouser numbers so it'll be easy. RS is great if you know the specs, or you can use a component matcher and then cross reference on what you need. This one for example http://www.fairchildsemi.com/crossref/crossrefSearch.do

BTW, I'm in Melbourne or for our Sepo friends, Mel-born

Click to expand...

Great info.

Thanks maaaaaaaaaaaaaaaate :thmbsp:

this is just the start - many replacement parts numbers are missing. mostly all the caps.

and liike the instructions say over and over - the lists are just a START (some entries turn out to just be "placeholders"), you have to visually verify each and every cap's value and change where appropriate - mainly the reason there are no "capacitor kits" out there for this - too many hassles about differences...

markthefixer said:

this is just the start - many replacement parts numbers are missing. mostly all the caps.

and liike the instructions say over and over - the lists are just a START (some entries turn out to just be "placeholders"), you have to visually verify each and every cap's value and change where appropriate - mainly the reason there are no "capacitor kits" out there for this - too many hassles about differences...

Click to expand...

You are THE MAN ! Thanks so much so far Mark. I am really looking forward to this project and with your continued help, I and everybody else undertaking the SA-7100 will be able to appreciate the finished product with pride !:thmbsp: