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Marantz Transistor/Diode/Trimmer Sub Guide

Boogies1018 said:
I’m trying to understand the ay and ays at the end of the part number. My 140 is frustrating me and I had to take a couple of days off. 2sa794=Ksa1220ay on h711 and h712 is 2sc1567=Ksc2690ay according to Steve’s awesome list. Well I ended up with ksa1220ays and ksc2690ays. Using these it stays in power protect and the relay won’t energize. If I put the OG 2sc1567 back in h712 comes up. I can’t figure out if the s at the end is the problem. Same problem with both amps. And it is possible I’ve over thought this also :)
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These subs were found searching the threads for what had worked for other people. In some cases, I could only find one reference, and the suitability of the sub might be a bit less reliable. I don’t think the S in the suffix changes any of the specs. It might be that in your particular application, that sub isn’t ideal. If you find one that works, please let me know, and I’ll put it on the list. Good luck!

Edit: Searching on 2SC1567, I see a couple of people used KSC3503, and one used MJE15032G. But several people used the KSC2690AY.
 
That's how I originally came up with my shopping list was searching around then after the stuff was on the way found yours and used it to crosscheck. I started plugging away patted myself on the back and nothing, been troubleshooting ever since. That's where I started triple-checking part numbers and noticed the ays and ay at the end differences and thought maybe.
 
The datasheet seems to point to all versions with an A in the suffix having the same specs except for gain. The Y specifies the gain. Sometimes that last letter designates how they are packaged for shipping— bulk, ammo pack, etc., but the datasheet doesn’t say.
 
Boogies1018 said:
I’m trying to understand the ay and ays at the end of the part number. My 140 is frustrating me and I had to take a couple of days off. 2sa794=Ksa1220ay on h711 and h712 is 2sc1567=Ksc2690ay according to Steve’s awesome list. Well I ended up with ksa1220ays and ksc2690ays. Using these it stays in power protect and the relay won’t energize. If I put the OG 2sc1567 back in h712 comes up. I can’t figure out if the s at the end is the problem. Same problem with both amps. And it is possible I’ve over thought this also :)
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There is no internal difference. The Y is the gain group code. The S is an environmental compliance code (can include lead and/or mold material changes, or other process changes), and the AYSTU is TUbe packaging. The transistor die itself hasn't changed. Something doesn't want to play well with these for some reason. BUT your DC Offset (and BIAS) may be different and needs adjusted in to below the protection threshold.
 
Boogies1018 said:
That's how I originally came up with my shopping list was searching around then after the stuff was on the way found yours and used it to crosscheck. I started plugging away patted myself on the back and nothing, been troubleshooting ever since. That's where I started triple-checking part numbers and noticed the ays and ay at the end differences and thought maybe.
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Don't overlook the possibility of rogue ceramic capacitors. I was chasing my tail on a 2250B and finally found a nearly shorted (34 Ohms) 500v ceramic capacitor. Who would have thought a 500v cap would short on a 41v rail? Not me, that's for sure. :dunno:
 
I will check that out, one thing I noticed comparing notes is when I was looking for subs for H709 2sc496 I had found 2n4923G, H713 2sc1625 I had ksc2073tu and H714 2sa815 I found sub KSA940TU. On Steve's list, he has TIP29C and TIP30C for H713 and H714 and nothing for H709. I usually bookmark where I found what subs now I can't find it for H713 and 714, but now I'm second-guessing if that is where my problem is. H709 I found here :https://audiokarma.org/forums/index.php?threads/current-2sc496-replacement-for-2270.584062/
 
I have been adding Bourns trimmer sub numbers for models as I come across them. I changed the title to read Marantz Transistor/Diode/Trimmer Sub Guide. If you have favorite trimmer replacements for a particular model, please post them and I will add them to the list. Thanks!
 
Boogies1018 said:
I will check that out, one thing I noticed comparing notes is when I was looking for subs for H709 2sc496 I had found 2n4923G, H713 2sc1625 I had ksc2073tu and H714 2sa815 I found sub KSA940TU. On Steve's list, he has TIP29C and TIP30C for H713 and H714 and nothing for H709. I usually bookmark where I found what subs now I can't find it for H713 and 714, but now I'm second-guessing if that is where my problem is. H709 I found here :https://audiokarma.org/forums/index.php?threads/current-2sc496-replacement-for-2270.584062/
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So if I put ksa1220 in place of 2sa794 and ksa2690 in place of 2sc1567 on 711 & 712 of p700 amp board it stays in power protection. I put the old transistor back and it comes up. I did notice the originals hfe’s are 97 & 115. The new ones hfe 290 &206, those being so high over the original ones cause it to stay in power protection? Maybe I need to find subs with lower hfe’s closer to the original?
 
If it works with the old transistors, why change? I’m not a fan of wholesale transistor replacement. The small differences in each one can add up to something that won’t work as it should.
 
Steven Tate said:
If it works with the old transistors, why change? I’m not a fan of wholesale transistor replacement. The small differences in each one can add up to something that won’t work as it should.
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Cause I did something I never ever do and I kick myself for a week now doing it. When I finished the one side I trashed the old parts before fully testing, so now I have only one side I can test the old stuff with. I work on copiers and I never chunk anything until the customers backup and going just in case. Idk what I was thinking.
 
Boogies1018 said:
Cause I did something I never ever do and I kick myself for a week now doing it. When I finished the one side I trashed the old parts before fully testing, so now I have only one side I can test the old stuff with. I work on copiers and I never chunk anything until the customers backup and going just in case. Idk what I was thinking.
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What model are you working on?
 
Boogies1018 said:
Model 140 power amp. The p700 amp boards
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If you don't have the old ones, I would probably try some of the alternative subs that you will find with a search. Of course, the problem could actually be with some other subbed component somewhere.

BTW, the best way to get the most brains and the most experience working on this dilemma is to start a thread with a title related to the 140. More people will see it, and some may have dealt with replacing these transistors.
 
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So I've searched and found a couple of post on a p700 board on 2275's and they used
H711 for 2SA794 - sub KSA1381 instead of ksa1220ay that I have
H712 for 2SC1567 - sub KSC3503 instead of ksc2690ay that I have
I'm trying to decode the datasheets and wanted to get a 2nd opinion
 
Boogies1018 said:
So I've searched and found a couple of post on a p700 board on 2275's and they used
H711 for 2SA794 - sub KSA1381 instead of ksa1220ay that I have
H712 for 2SC1567 - sub KSC3503 instead of ksc2690ay that I have
I'm trying to decode the datasheets and wanted to get a 2nd opinion
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The lc (collector current) for the 2SA794 is .5A, but the KSA1381 is only .1A. So I wouldn't use it. The MJE243/253 complimentary pair would be fine too if you have them. But the gain (hFE) of the KSA1220AY is more to the liking depending on the gain group of the originals. If the manual wants (Q) rank, the MJE is fine. If it wants (R) rank, the 1220AY would be best. If it says (Q,R), then either one is fine for hFE.
 
Skywatcher said:
The lc (collector current) for the 2SA794 is .5A, but the KSA1381 is only .1A. So I wouldn't use it. The MJE243/253 complimentary pair would be fine too if you have them. But the gain (hFE) of the KSA1220AY is more to the liking depending on the gain group of the originals. If the manual wants (Q) rank, the MJE is fine. If it wants (R) rank, the 1220AY would be best. If it says (Q,R), then either one is fine for hFE.
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The manual shows ht10741q and ht315671q. I have the 1220ay’s in there now and it won’t energize the relay. The originals will. And if my stupidity hadn’t tossed the rt side parts I’d put them back. So now I’m trying to find replacements.
 
I see you need a replacement for a 2SD315E with TO-66 case. I believe an option is a NTE 175 with a TO-66 case. They cost about $6 from NTE. NTE has the 2n4231 as a replacement too but TO-220. I hate the change to a TO-220. I found a stash of ECG 291's and ECG 292'S that work too. I believe the ECG company changed to NTE 30 ??? years ago. Hope this works.
 
Bvers1 said:
I see you need a replacement for a 2SD315E with TO-66 case. I believe an option is a NTE 175 with a TO-66 case. They cost about $6 from NTE. NTE has the 2n4231 as a replacement too but TO-220. I hate the change to a TO-220. I found a stash of ECG 291's and ECG 292'S that work too. I believe the ECG company changed to NTE 30 ??? years ago. Hope this works.
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Thanks! I’ll get it on the list.
 
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