SX-1280: burnt spot on power supply board?
- Thread starter mc_sx880
- Start date
I have spent considerable time reading through all the links you all provided. It's a lot to go through and every bit is appreciated. I can go further with that, but at this time I am approaching the limit of my ability to understand a few things
mattsd, and Larry,
Thank you both for the lists. I want to help update them, as well as order the parts I need. But I am lost as to how to research the caps that are not available at Mouser, to determine suitable replacements.
The link posted directly to the Mouser website in the form of a shopping cart, is fantastic.
Hope I am not asking too much, because it is very generous of you to give me this much.
I appreciate it.
mattsd, and Larry,
Thank you both for the lists. I want to help update them, as well as order the parts I need. But I am lost as to how to research the caps that are not available at Mouser, to determine suitable replacements.
The link posted directly to the Mouser website in the form of a shopping cart, is fantastic.
Hope I am not asking too much, because it is very generous of you to give me this much.
I appreciate it.
I think I figured out what to do.
I copied/pasted each of the numbers in the mattsd list, since it seems to be most recent, into the mouser site.
The only part out of stock is; 512-KSA1220AYS
That has a 34 week wait.
Total price, including the out of stock item, shipped USPS Priority mail is $194.79.
Thanks for hanging in there with me.
I copied/pasted each of the numbers in the mattsd list, since it seems to be most recent, into the mouser site.
The only part out of stock is; 512-KSA1220AYS
That has a 34 week wait.
Total price, including the out of stock item, shipped USPS Priority mail is $194.79.
Thanks for hanging in there with me.
Last edited:
Watthour
Electron Rancher - JS3600
Given the circuit application, I might suggest that a KSA992F could be used in the EQ amplifier stage along with its complimentary part, the KSC1845F in the Q9/10 and Q7/8 positions. They are slightly lower power, but I suspect that 50mA should be plenty for the EQ amp. They are used successfully in the SX-1250 EQ amp outputs all the time.
Thanks a lot for the information. I apologize for being a little slow to pick up on this, and not clear on what you mean. Should I substitute two of the KSA992F for the two KSA1220AYS that are not available, and also get 2 of the KSC1845F... instead of...what? Or in addition to...?
Is the KSA992F different than the KSA992FBU, and the KSC1845F different than the KSC1845FTA?
I know you guys say, there's no such thing as a dumb question, but for some reason my question seems dumb, even to me.
Is the KSA992F different than the KSA992FBU, and the KSC1845F different than the KSC1845FTA?
I know you guys say, there's no such thing as a dumb question, but for some reason my question seems dumb, even to me.
The KSA992 is the part # F is the gain #. BU, TA, etc is the shipping type. Bulk, Tape loaded for machine installation.
KSA992FBU replaces 512-KSA1220AYS (Q9,Q10)
KSC1845FTA replaces 512-KSC2690AYS or KSC2690AYSTU (Q7,Q8)
KSA992FBU replaces 512-KSA1220AYS (Q9,Q10)
KSC1845FTA replaces 512-KSC2690AYS or KSC2690AYSTU (Q7,Q8)
So YOU were the reason for our "extended" tour.Small world, eh?
I believe the Ranger was supposed to replace the Connie, or the Kittyhawk? Can't remember, when we were headed to Australia in 1979 and center-punched a Liberian oil tanker... That was something.
http://uss-rangerguy.com/collision.htm
Subic bay, Grande Island. "Memories are made of this"
We never played "bumper boats", but did have a saboteur on board. Tried to drain the lubricating oil for the screw shafts.
Fortunately, someone caught it in time. Don't know if they ever found out who did it though.Well, not me personally...but they canned the Captain, XO and Navigator for that little momentary lapse in their aircraft carrier driving skills. 
As it turned out, most if not all people consider it rude to smash an oil tanker with an aircraft carrier, even if it isn't nuclear powered.
As it turned out, most if not all people consider it rude to smash an oil tanker with an aircraft carrier, even if it isn't nuclear powered.
mattsd
Super Member
Those transistors were picked for their power dissipation, Q7-10 make up the SEPP output stage and dissipate a decent amount of power. The KSC1845 and KSA992 do not have the power dissipation needed for those positions. Use 757-TTC004BQ for the 2SC1885 and 757-TTA004BQ for the 2SA912.
Man...
I probably don't understand this, but what I think you said is, that in my BOM I need to:
-remove 2 of 3 : #512-KSC2690AYS
(because though BOM requires 3, only 2 are used for Q7 & Q8)
-remove 2 of 2 : #512-KSA1220AYS
(because it is not available)
-add 2 : #757-TTC004BQ
(to replace 2SC1885 (or 512-KSC2690AYS))
-add 2: #757-TTA004BQ
(to replace 2SA912 (or 512-KSA1220AYS))
Am I even in the same ballpark???
I won't order anything till I clearly understand.
I probably don't understand this, but what I think you said is, that in my BOM I need to:
-remove 2 of 3 : #512-KSC2690AYS
(because though BOM requires 3, only 2 are used for Q7 & Q8)
-remove 2 of 2 : #512-KSA1220AYS
(because it is not available)
-add 2 : #757-TTC004BQ
(to replace 2SC1885 (or 512-KSC2690AYS))
-add 2: #757-TTA004BQ
(to replace 2SA912 (or 512-KSA1220AYS))
Am I even in the same ballpark???
I won't order anything till I clearly understand.
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Here is what I have so far, below is mattsd's BOM, with the addition of
(2) 757-TTC004BQ
(2) 757-TTA004BQ
and the removal of
(2) 512-KSC2690AYS
(2) 512-KSA1220AYS
BOM List
647-UKL1H2R2KDDANA | 14
647-UKL1H3R3MDDANA | 2
647-UKL1H4R7KDDANA | 8
647-UKL1E100KDDANA | 4
505-MKS2B041001C00KS | 4
647-UPW2A101MHD | 4
667-EEU-FM1V221 | 3
647-TVX2A471MCD | 2
647-UPW2A221MHD | 2
647-UPW1C220MDD | 2
647-UPW1H101MPD | 4
647-UPW1E470MDD | 1
647-UPW1E101MED | 2
667-EEA-FC1E100 | 1
667-EEU-FM1E101 | 12
667-EEU-FM1V330 | 2
667-EEU-FM1C471 | 2
647-UES1V4R7MDM | 2
505-MKS20.22/63/5 | 4
80-F612JF224J063A | 2
647-UPW1H220MDD | 2
647-UPW1H100MDD | 2
647-UPW1H331MPD | 2
647-UPW1E102MHD | 2
647-UPW1V102MHD | 1
647-UPW1V330MDD | 2
647-UPW1V100MDD | 3
647-UPW1V221MPD | 1
512-KSA992FBU | 10
512-KSC1845FTA | 12
512-KSC2383YTA | 3
512-KSA1013YBU | 2
863-MJE15032G | 1
863-MJE15033G | 2
512-KSC2690AYS | 3
512-KSA1220AYS | 2
652-3386H-1-101LF | 2
652-3296P-1-204LF | 2
653-MY2-02-DC48 | 1
653-LY2-0-DC48 | 1
661-E36D101N223TDB7M | 4
(2) 757-TTC004BQ
(2) 757-TTA004BQ
and the removal of
(2) 512-KSC2690AYS
(2) 512-KSA1220AYS
BOM List
647-UKL1H2R2KDDANA | 14
647-UKL1H3R3MDDANA | 2
647-UKL1H4R7KDDANA | 8
647-UKL1E100KDDANA | 4
505-MKS2B041001C00KS | 4
647-UPW2A101MHD | 4
667-EEU-FM1V221 | 3
647-TVX2A471MCD | 2
647-UPW2A221MHD | 2
647-UPW1C220MDD | 2
647-UPW1H101MPD | 4
647-UPW1E470MDD | 1
647-UPW1E101MED | 2
667-EEA-FC1E100 | 1
667-EEU-FM1E101 | 12
667-EEU-FM1V330 | 2
667-EEU-FM1C471 | 2
647-UES1V4R7MDM | 2
505-MKS20.22/63/5 | 4
80-F612JF224J063A | 2
647-UPW1H220MDD | 2
647-UPW1H100MDD | 2
647-UPW1H331MPD | 2
647-UPW1E102MHD | 2
647-UPW1V102MHD | 1
647-UPW1V330MDD | 2
647-UPW1V100MDD | 3
647-UPW1V221MPD | 1
512-KSA992FBU | 10
512-KSC1845FTA | 12
512-KSC2383YTA | 3
512-KSA1013YBU | 2
863-MJE15032G | 1
863-MJE15033G | 2
512-KSC2690AYS | 3
512-KSA1220AYS | 2
652-3386H-1-101LF | 2
652-3296P-1-204LF | 2
653-MY2-02-DC48 | 1
653-LY2-0-DC48 | 1
661-E36D101N223TDB7M | 4
Thanks, mattsd!
Your help is greatly appreciated... no need to be sorry. Most of this is a challenge for me but I eventually got to the answer. Just needed confirmation.
After 30+ years working a job where I didn't have to think hard about what I was doing, this will help get my mind back in shape...but right now my little brain muscles, all 3 of them...are just a little sore from trying to absorb and interpret so much information here.
If I could ask another question... I searched this site for quite a while and couldn't locate it, but is there is a BOM for a PL-71, even if for only the motor caps? I will start a new thread if that's the way, but I figured if I could throw those parts in with this SX-1280 order I could save a few bucks on shipping.
Thanks again.
Mike
Your help is greatly appreciated... no need to be sorry. Most of this is a challenge for me but I eventually got to the answer. Just needed confirmation.
After 30+ years working a job where I didn't have to think hard about what I was doing, this will help get my mind back in shape...but right now my little brain muscles, all 3 of them...are just a little sore from trying to absorb and interpret so much information here.
If I could ask another question... I searched this site for quite a while and couldn't locate it, but is there is a BOM for a PL-71, even if for only the motor caps? I will start a new thread if that's the way, but I figured if I could throw those parts in with this SX-1280 order I could save a few bucks on shipping.
Thanks again.
Mike
Service manual here. Suggest bookmark the link. Scroll down to the PL71 for the manual. 1transistor, 3 caps, 4 Diodes and a Zener. http://www.kallhovde.com/pioneer/Pioneer/Main scan page.html
2sd234 = 512-KSC2073TU
SIB01-01 = 512-1n4004 x4
330uf/35v = 647-UPW1H331MPD (*)
33uf/35v = 647-UPW1H330MED (*)
100uf/25V = 647-UPW1V101MPD(*)
WZ-192 = 19V 0.5W = 512-1N5249BTR
(*) NOTE: Voltages on caps raised 1 level above original. 35V caps are now 50V and 25V cap is now 35V. This is to compensate for higher wall voltages of today vs. back when this unit was built.
BOM for Mouser
512-KSC2073TU
512-1n4004
512-1n4004
512-1n4004
512-1n4004
647-UPW1H331MPD
647-UPW1H330MED
647-UPW1V101MPD
512-1N5249BTR
I was at the Dispensary @ T.I. from 1974-76. I was a little crazier than the avg sailor and went Sub's in 76. Ended up in Charleston, S.C. on a Boomer. Charleston back then was the "Mary Jane Rotten Crotch" of the East Coast. Worse than Norfolk.
2sd234 = 512-KSC2073TU
SIB01-01 = 512-1n4004 x4
330uf/35v = 647-UPW1H331MPD (*)
33uf/35v = 647-UPW1H330MED (*)
100uf/25V = 647-UPW1V101MPD(*)
WZ-192 = 19V 0.5W = 512-1N5249BTR
(*) NOTE: Voltages on caps raised 1 level above original. 35V caps are now 50V and 25V cap is now 35V. This is to compensate for higher wall voltages of today vs. back when this unit was built.
BOM for Mouser
512-KSC2073TU
512-1n4004
512-1n4004
512-1n4004
512-1n4004
647-UPW1H331MPD
647-UPW1H330MED
647-UPW1V101MPD
512-1N5249BTR
I was at the Dispensary @ T.I. from 1974-76. I was a little crazier than the avg sailor and went Sub's in 76. Ended up in Charleston, S.C. on a Boomer. Charleston back then was the "Mary Jane Rotten Crotch" of the East Coast. Worse than Norfolk.
Watthour
Electron Rancher - JS3600
That's informative. I'm actually a little surprised that the phono amp output would exceed 50mA and ½W, but I've never measured. The originals were rated at 100mA / 34W, so it would make sense, and explain the original substitution selection as the 1220 and 2690. The 1250 must be just different enough to get away with the 50mA devices. I'm back to the diagrams to learn more.
It is output stage bias current that determines the idling power dissipation, the difference between using a 2sc1775 and a 2sc1885.
on the 1280, 1V/110 ohm = 9.1mA * Vce(30V)=0.27W
1250 hard to figure since we can not determine the o/p stage idle current from the information
on the 1280, 1V/110 ohm = 9.1mA * Vce(30V)=0.27W
1250 hard to figure since we can not determine the o/p stage idle current from the information
Simulation Results
For the SX-1280 AWF-031 Eq Amp assembly:
Q7,8 (KSC1845) / Q9,10 (KSA992) Pd=291mW
Q7,8 (KSC2383) / Q9,10 (KSA1013) Pd=262mW
Q7,8 (KSC3503) / Q9,10 (KSA1381) Pd=254mW
Q7,8 (KSC2690) / Q9,10 (KSA1220) Pd=200mW
For the SX-1250 AWF-021 Eq Amp assembly:
Q7,8 (KSC1845) / Q9,10 (KSA992) Pd=121mW
This confirms that the C1845/A992 is much better suited for use in the SX-1250 Eq Amp (Q7-Q10) than in the SX-1280.
For the SX-1280 AWF-031 Eq Amp assembly:
Q7,8 (KSC1845) / Q9,10 (KSA992) Pd=291mW
Q7,8 (KSC2383) / Q9,10 (KSA1013) Pd=262mW
Q7,8 (KSC3503) / Q9,10 (KSA1381) Pd=254mW
Q7,8 (KSC2690) / Q9,10 (KSA1220) Pd=200mW
For the SX-1250 AWF-021 Eq Amp assembly:
Q7,8 (KSC1845) / Q9,10 (KSA992) Pd=121mW
This confirms that the C1845/A992 is much better suited for use in the SX-1250 Eq Amp (Q7-Q10) than in the SX-1280.
