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Once more Sansui transistor substitutions

Perhaps a BC550C would be a suitable alternative, you just have to be creative with the lead orientation, the small signal gain is typically 600 (range from 450 to 900).
 
unfortunately, there is the YMMV thing. I did buy 100 each KSA992/KSC1845. Now KSC1845 was around 300 and the KSA992 400. I decided to order again later (and hopefully from another batch) and then they were around 400 so I was happy.

The BC550/560 I bought 100 each also, were definately below 600 all of them.

Guess it is a matter of being lucky.
 
My KSC1845s measured about 400, but the interesting thing is so far every one has been identical. Nothing like the old days where device hfe would vary 3:1 and sometimes more. My go-to for a high gain very low noise device has been the 2N5088, but the 1845 is actually quieter than my old-production ones. 1845 also has a flat curve family, that is, the hfe doesn't vary with C-E voltage. The 871 has a rising family. IOW, the highest hfe is at the upper voltages. I've never considered that a desirable thing, but can't give a good reason why.
 
At risk of sounding like a broken record (I've said this in several threads now), before agonizing about subs having the same gain, check the circuit and see if it matters, as gain is often 'clamped' by the circuit design (not unlike how the very large open gain of an opamp is limited by the choice of nearby resistors) to limit gain for reasons of achieving desired levels suitable for subsequent stages and limiting distortion. The sub only needs to be sufficiently high in gain compared to the circuit designed gain. If the circuit gain is e,g, ~30, whether you use a transistor with 200 or 600 gain is often irrelevant. (but in this example I wouldn't use something with hFE of say 0-100). Inside of signal path and outside of MC phono amps, a stage gain of e.g. 600, is unlikely. Think about your ~2V coming into your amp... that gets beefed up to just a few tens of volts over many stages.

This scenario is not always the case (especially outside of signal path) where other types of circuits are involved, and often changing gain is a problem.
 
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I wouldn't get overly concerned about hfe, but, and I need to confirm this on the bench, I suspect as hfe gets too low, THD in simple 1-2 device stages, rises. Japanese transistors tended to have much higher hfe than common 2N numbers, and the designers relied on it. Thus, when I pick a sub, I try to curve trace as many original parts as possible, and find something as similar as possible.
 
ToniCH said:
Please note, the list on post #1 is obsolete and here is the corrected list per posts on this thread. This is less elegant solution (to post the whole list again vs. correcting the original) but only kind of correction I can make currently. Again, this is not absolutely correct list, I have only gathered what people have used or recommended previously in dozens of old threads into one list. So, double check the data before ordering and installing parts.

If you spot errors please point them out and I'll make the correction if I can (I guess I have couple of hours to correct this list before I lose editing rights?)..


Original ---- Substitution(s)

2SA561 --- KSA733C (C-suffix= collector center)
2SA562 --- BC327
2SA606/2SC959 --- NTE129MCP (Complementary pair product #)
2SA640 --- KSA992 or the beefier ZTX795A
2SA697 --- ZTX795A
2SA706 --- KSA1381ESTU, BD136
2SA726 --- KSA992FTA/-FBU, BC560
2SA733 --- KSA733C (C= collector center)
2SA745 --- MJ15004G, upgrade: MJ21193
2SA747 --- MJ21193G (for example AU-9900/11000 output)
2SA750 --- KSA992FBU
2SA818 --- KSA1381 (pin order!), KSA1142, (2SA0914?)
2SA839 --- MJE15033 (PNP). (or MJE15035)
2SA847 --- KSA992
2SA850 --- KSA1013, KSA992
2SA896 --- KSA1381ESTU (pin order!)
2SA899 --- KSA1142, KSA1220AYS, KSA1381
2SA908 --- MJ21193G, MJ21195G (for example AU-20K output)
2SA914 --- KSA1142, KSA1381
2SA917 --- 2N5400 (pin order!)
2SA939 --- KSA1381, KSA1220AY
2SA958 --- Sansui-parts says 2SA839 can be replaced with 2SA958 - what about other way around?
2SA968 --- MJE15033
2SA981 --- MJ21194G
2SA1105 --- 2SA1695
2SA1106 --- 2SA1695 (avail. fr. Digikey), NJW1302G


2SB327 --- KSA1220A
2SB507 --- MJE15033G
2SB507(E,F) --- KSA1010Y
2SB526 --- MJE15033
2SB527 --- MJE15033, KSA1220
2SB528 --- 2SA1837 (TO220, fully insulated case)
2SB528(E) E=150~300 PNP --- KSA1220A(Y)S Y=160~320 PNP TO-126
2SB536 --- KSA1304Y, MJE15033G
2SB537 --- MJE15031G
2SB545(A) --- MJ21193G
2SB560 PNP --- KSA916 PNP KSA916(Y)TA Y=120~240 TO-92L


2SC458 --- 2SC2240, 2SC1345
2SC735 --- BC337
2SC871 --- 2SC2240, KSC1845, or even BC549C or BC550C (pin out differences!)
2SC875 --- ZTX694B
2SC945 --- KSC945C (C= collector center)
2SC983 --- KSC1845
2SC1116 --- MJ21194G (for example AU-9900/11000 output)
2SC1124 --- MJE15032G but that might be overkill and you could consider KSC2073
2SC1211 --- KSC2383
2SC1313 --- KSC1815
2SC1364 --- KSC945C (best if used on protection board), KSC2690 (for more demanding use)
2SC1400 --- KSC1845
2SC1402 --- MJ21194
2SC1403A --- MJ15003G, upgrade MJ21194
2SC1585 --- MJ21194G, MJ21196G (for example AU-20K output)
2SC1628 --- KSC3503 (pin order!), (2SC1953?)
2SC1669 --- MJE15032
2SC1708 --- KSC1845
2SC711 --- KSC945C(G)TA G=200~400 TO-92
2SC1735 --- KSC2383, KSC1845
2SC1811 --- KSC3503ESTU
2SC1904 --- KSC3503, KSC2690AY
2SC1951 --- ZTX694B
2SC1953 --- KSC2682, KSC3503
2SC959/2SA606 --- NTE129MCP (Complementary pair product #)
2SC1983 --- TIP112F or KSD1273Q
2SC2071 --- KSC3503, KSC2690AY
2SC2238 --- MJE15032
2SC2261 --- MJ21193G
2SC2580 --- 2SC4468
2SC2581 --- 2SC4468 (avail. fr. Digikey), NJW3281G


2SD188(A) --- MJ21194G
2SD247 --- MJ15003G
2SD313(E,F) --- KSC2334Y
2SD356 --- MJE15032
2SD357 --- KSC2690A, KSC2073
2SD358(E) E=150~300 NPN --- KSC2690A(Y)S Y=160~320 NPN TO-126
2SD381 --- KSC3296Y, MJE15032
2SD382 --- MJE15030G, MJE15032
2SD438 NPN --- KSC2316 NPN KSC2316(Y)TA Y=120~240 TO-92L

------------------------
Here is some diode and zener subs I've seen mentioned while collecting transistors:


Diodes/rectifiers:

10D1 --- 1N5392, 1N5393, EGP20B
10D2 --- 1N5392, 1N5393, EGP20D, EGP30D
30D2 --- 1N5402G, EGP50D
1S1588 --- 1S2473, 1N4148
1S2473 ---- 1N4148, 1N4149
VD1212 --- 2pcs of 1N4148 connected in series
1S1850 --- MUR1620CTG (TO220) - or use 1N5393G (200V 1.5A) or 2A03 (200V/2A) to make your own Common Cathode -diode pack
1S1850R --- MUR1620CTRG (TO220) - or use 1N5393G (200V 1.5A) or 2A03 (200V/2A) to make your own Common Anode -diode pack


Zeners

EQB01-22 --- BZV85-C22 or 1N4748A
RD-13A --- TZX13A-TR
RD-15E --- ??? Maybe 1N5245BTR, comments?

RD-22E --- ??? Maybe 1N5251BTR, Comments?
Click to expand...



The only thing I see right off is the replacements for the 2SD-381 and the 2SD-382. This list shows that one of the replacements for the 2SD-381 is the MJE-15032 and one of the replacements for the 2SD-382 is also the MJE-15032. Is it possible to use the MJE-15032 for both the 2SD-381 and the 2SD-382?
 
You always need to consider transistor reference designator codes when you are researching "suitable subs". I haven't yet found anything definitive about KSA and KSC codes. Fairchild? Kennedy Space Center?

There is a good write-up on transistor designations here: https://www.elexp.com/Images/Reading_Transistor_Markings.pdf , but nothing about KSA or KSC.

The three standards listed are JEDEC (Joint Electron Device Engineering Council), JIS (Japanese Industrial Standards), and Pro-Electron (European).

Numbers in the JEDEC are assigned sequentially by dates, thus a higher number indicates a more recent design (or re-design!).

The JIS codes are the ones we see most often, and start with a "1" for diodes or a "2" for transistors. The next 2 letters are:

SA: PNP HF transistor
SB: PNP AF transistor . . .(Audio Frequency)
SC: NPN HF transistor
SD: NPN AF transistor . . .(Audio Frequency)
SE: Diodes SF: Thyristors
SG: Gunn devices
SH: UJT
SJ: P-channel FET
SK: N-channel FET
SM: Triac
SQ: LED
SR: Rectifier
SS: Signal diodes
ST: Avalanche diodes
SV: Varicaps
SZ: Zener diodes

The code for transistors always begins with "2S", and is sometimes omitted. So if you see a "C733" and cannot find any other info, try looking for a "2SC733".

Some manufacturers use their own codes like Motorola's MJE15032 (power transistor, plastic case) or Texas Instrument's TIP112 (power transistor, plastic case).

Maybe this will help someone - - -
 
Hyperion said:
Yes, the 2SD381 and 2SD382 are both NPN, (both can be substituted with the MJE15032, NPN), and these are complementary to the 2SB536 and 2SB537 (PNP) respectively.
Click to expand...
Thanks a lot for clearing this up for me. I have accumulated a lot of the original transistors for the BA-3000 over the years as I have had 2 of them for over 20 years now. Unfortunately I am now starting to run low or completely out of some of the parts due to repairing friends or friends of friends amps. I really need this list now. Thanks a lot for all your work in making this list. It has made a lot of peoples lives a lot easier.
 
I must ask if the OP is actually updating the frontpage list. This is a golden post.
EDIT: Already read about editting the old posts issue, too bad.
 
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Can the original post be edited by the mods? There is an error with 2sa981 -> MJ21194G and 2sc2261 -> MJ21193G.

These should be reversed, correct subs are -

2sa981 -> MJ21193G and
2sc2261 -> MJ21194G

Really had me going for a loop today :/
 
Thanks for the list Toni,
I just want to keep it going, I added some SanKen transistors and a couple of zeners.
I hope you don't mind an updated list, I tried to copy all corrected information from other posts.
I didn't verify any of the corrections, except for what I added so if anyone see's any corrections, mistakes or more updates please let me know and I will edit them in.

2SA561 --- KSA733C (C-suffix= collector center)
2SA562 --- BC327
2SA606/2SC959 --- NTE129MCP (Complementary pair product #)
2SA640 ---KSA992 or ZTX795A
2SA697 ---ZTX795A
2SA706 --- KSA1381ESTU, BD136
2SA726 --- KSA992FTA/-FBU, BC560
2SA733 --- KSA733C (C= collector center)
2SA745 --- MJ15004G, upgrade: MJ21193
2SA747 --- MJ21193G (for example AU-9900/11000 output)
2SA750 --- KSA992FBU
2SA818 --- KSA1381 (pin order!), KSA1142, (2SA0914?)
2SA839 --- MJE15035, 2SC1669
2SA847 --- KSA992
2SA850 --- KSA1013, KSA992
2SA896 --- KSA1381ESTU (pin order!)
2SA899 --- KSA1142, KSA1220AYS, KSA1381
2SA906 ---KSA992
2SA908 --- MJ21193G, MJ21195G (for example AU-20K output)
2SA914 --- KSA1142, KSA1381
2SA917 --- KSC916(Y)TA
2SA939 --- KSA1381, KSA1220AY
2SA958 --- 2SA839?
2SA968 --- MJE15033
2SA981 --- MJ21193G
2SA992 ---KSA992
2SA1105 --- 2SA1695
2SA1106 --- 2SA1695 (avail. fr. Digikey), NJW1302G
2SA1170 ---2SA1493or94 SanKen Case MT200 Late G-7700 output

2SB327 --- KSA1220A
2SB507 --- MJE15033G
2SB507(E,F) --- KSA1010Y
2SB526 --- MJE15033
2SB527 --- MJE15033, KSA1220
2SB528 --- 2SA1837 (TO220, fully insulated case)
2SB528(E) ---KSA1220A Case TO-26
2SB536 --- KSA1304Y, MJE15033G
2SB537 --- MJE15031G
2SB545(A) --- MJ21193G
2SB560 --- KSA916, KSA916(Y)TA Case TO92L

2SC281 --- KSC1815
2SC458 --- 2SC2240, 2SC1345
2SC711 ---KSC945C(G)TA Case TO-92
2SC735 --- BC337
2SC839 ---MJE15033or 35
2SC871 --- 2SC2240, KSC1845, or even BC549C or BC550C (pin out differences!)
2SC875 ---ZTX694B
2SC945 --- KSC945C (C= collector center)
2SC983 --- KSC1845
2SC1116 --- MJ21194G (for example AU-9900/11000 output)
2SC1124 ---MJE15032G or stronger KSC2073
2SC1211 ---KSC2383
2SC1313 --- KSC1815
2SC1364 --- KSC945C (best if used on protection board), KSC2690 (for more demanding use)
2SC1400 --- KSC1845
2SC1402 --- MJ21194
2SC1403A --- MJ15003G, upgrade MJ21194
2SC1585 --- MJ21194G, MJ21196G (for example AU-20K output)
2SC1628 --- KSC3503 (pin order!), (2SC1953?)
2SC1669 --- MJE15032
2SC1708 --- KSC1845
2SC711 --- KSC945C(G) TO-92
2SC1735 --- KSC2383, KSC1845
2SC1775 ---KSC1845FTA
2SC1811 --- KSC3503ESTU
2SC1845 ---KSC1845
2SC1904 --- KSC3503, KSC2690AY
2SC1951 --- ZTX694B
2SC1953 --- KSC2682, KSC3503
2SC959/2SA606 --- NTE129MCP (Complementary pair product #)
2SC1983 --- TIP112F or KSD1273Q
2SC2071 --- KSC3503, KSC2690AY
2SC2238 --- MJE15032
2SC2261 -> MJ21194G
2SC2580 --- 2SC4468
2SC2581 --- 2SC4468 (avail. fr. Digikey), NJW3281G
2SC2774 --- 2SC3857or58 SanKen Case MT-200 Late G-7700 output

2SD188(A) --- MJ21194G
2SD247 --- MJ15003G
2SD313(E,F) --- KSC2334Y
2SD356 --- MJE15032
2SD357 --- KSC2690A, KSC2073

2SD358(E) KSC2690A Case TO126
2SD381 --- KSC3296Y, MJE15032
2SD382 --- MJE15030G, MJE15032

2SD438 ---KSC2316, KSC2316(y)TA Case TO-126


------------------------

Here is some diode and zener subs I've seen mentioned while collecting transistors:

Diodes/rectifiers:
10D1 --- 1N5392, 1N5393, EGP20B
10D2 --- 1N5392, 1N5393, EGP20D
30D2 --- 1N5402G, EGP50D
1S1588 --- 1S2473, 1N4148
1S2473 ---- 1N4148, 1N4149
VD1212 --- 2pcs of 1N4148 connected in series
1S1850 --- MUR1620CTG (TO220) - or use 1N5393G (200V 1.5A) or 2A03 (200V/2A) to make your own Common Cathode -diode pack
1S1850R --- MUR1620CTRG (TO220) - or use 1N5393G (200V 1.5A) or 2A03 (200V/2A) to make your own Common Anode -diode pack

Zeners
EQB01-22 --- BZV85-C22 or 1N4748A
RD-13A --- TZX13A-TR
RD-15E --- ??? Maybe 1N5245BTR, comments?
RD-22E --- ??? Maybe 1N5251BTR, Comments?

RD-33F ---BZX85B33-TR
RD-18F ---1N4746A, 133
 
Adding my .02 ---
2SA798's, the 5 pin inline dual pnp transistors (b-c-e-c-b) often used in flat amp input stages of Sansui AU series gear are both becoming hard to locate and old enough now to become noisy, usually evidenced by occasional static bursts that come and go at random.
I have had good results using paired KSA992's face to face so the emitter pins line up with a touch of thermal compound and heat-shrink to hold them together. For extra piece of mind don't forget to gain match the 992's although the last batch I ordered were within 5hfe of each other across 20 pieces.
-Lee
 
Dcook154, no problem.

And anybody else: please do add and make corrections, its a community effort to update the list. Every now and then do republish the entire list with new corrections. And everybody remember - the last list on the thread is the newest with the up to date corrections, so only use that one! The list on the original post is obsolete so there is no point for mods to make single corrections there, they will not be updated to the last current list and will be lost.

I have no Sansui to fix now and probably will not have in near future so I won't be active updating the list.
 
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