hi everyone
I want to build Apex amplifier (HV23)(that I founded in page below (thread 44) :
http://www.diyaudio.com/forums/solid-state/162043-mosfet-amplifier-irfp240-irfp9240-5.html
I found all the parts in this schematic except Q9 (2sc4793) and Q10 (2SA1837)
but the salesman suggested me to use 2SC2073 and 2SA940 instead
and I'm so confused😕 that are they right for replacement??????
If anyone could help me I'll be grateful
I want to build Apex amplifier (HV23)(that I founded in page below (thread 44) :
http://www.diyaudio.com/forums/solid-state/162043-mosfet-amplifier-irfp240-irfp9240-5.html
I found all the parts in this schematic except Q9 (2sc4793) and Q10 (2SA1837)
but the salesman suggested me to use 2SC2073 and 2SA940 instead
and I'm so confused😕 that are they right for replacement??????
If anyone could help me I'll be grateful
Pretty much any power transistor should work there, say MJL3281 and MJL1302 should work.
However dont put my word on it, but rather ask Apex himself first.
However dont put my word on it, but rather ask Apex himself first.
Yes! JayCee is a reputable forum member, and the datasheet tells those transistors will do the job just fine.
Mouser has this transistors, they cost about 0.5Euro/pcs. The MJE150xx should be good replacement, only the higher internal capacitances can be problem.
Sajti
Sajti
2sa1837/c4793 are nice driver transistors.
They have reasonable parameters but far from the best available.
I would not settle for lesser performance when substituting, when there are many that can at least equal 1837 performance and quite a few that can better them.
Try APEX again and be patient.
They have reasonable parameters but far from the best available.
I would not settle for lesser performance when substituting, when there are many that can at least equal 1837 performance and quite a few that can better them.
Try APEX again and be patient.
The 2SC4793 datasheet gives an fT of 70MHz. The one for the MJE15034/MJE15035 quotes an fT of 'only' 30MHz. That might or might not be significant. I don't think so myself.
There is a source that lists both of them available for $1.29 each.
Electronix Online - Computer and Electronic Parts and Supplies
I have bought other items from them that were as promised.
I have no experience with the parts you request.
Electronix Online - Computer and Electronic Parts and Supplies
I have bought other items from them that were as promised.
I have no experience with the parts you request.
Nice table, but not quite useful, unfortunately.
If You check it, You can imagine, that the 2SC5171/2SA1930 are stronger, than the 2SC4793/2SA1837 pair. But this is absolutely not true, because the 100msec SOA for the 5171/1930 is 35mA at 100V, but 120mA for the 4793/1837.
Sajti
If You check it, You can imagine, that the 2SC5171/2SA1930 are stronger, than the 2SC4793/2SA1837 pair. But this is absolutely not true, because the 100msec SOA for the 5171/1930 is 35mA at 100V, but 120mA for the 4793/1837.
Sajti
Hi, sorry for bringing old thread up, but I have a 400W power amp with burned output stage. I found all parts but can not find driver transistors (2sSC4793/2SA1837).
output stage is 2SC5200/2SA1943, power supply is +-80V.
could you suggest me good replacement, is it ok to use MJE15034 suggested on page 1 ?
thanks
output stage is 2SC5200/2SA1943, power supply is +-80V.
could you suggest me good replacement, is it ok to use MJE15034 suggested on page 1 ?
thanks
+-80Vdc for 1943/5200 is very stressful for those outputs.
I'd suggest you investigate the required SOAR and see whether the 1943/5200 are up to what you need.
I'd suggest you investigate the required SOAR and see whether the 1943/5200 are up to what you need.
it is factory made power amp, burned because of my mistake, so it should be fine. I just don't know what drivers to use
I'm never hear about Unisonic manufacturer, they're really good?!
2SC4793 is really good driver transistor. 80mA@100V@DC SOA. I'm using 2SC4793 to drive 6 pairs Sanken 2SC3519A/2SA1386A @ 50mA Iq @ 70V rail.
Hard to find a transistor like them.
Of course, 2SC5171 better, but the SOA is problem.
2SC4793 is really good driver transistor. 80mA@100V@DC SOA. I'm using 2SC4793 to drive 6 pairs Sanken 2SC3519A/2SA1386A @ 50mA Iq @ 70V rail.
Hard to find a transistor like them.
Of course, 2SC5171 better, but the SOA is problem.
Like all reputable manufactrers, Unisonic (Taiwan) publish their own datasheets. Download, compare and decide for yourself. If you want that specification for replacements or new products then buy them, as it will be the best option, AFAIK. Profusion sells to the pro. sound industry for music and sound reinforcement applications to manufacturers and repairers. Don't just take my word for it, they wouldn't maintain such a narrow product range without good reason. I suggest it has to so with the quality and compatibility of the parts with the OEM ones.
It's the same with Renesas 2SD669/B649 drivers. Unisonic also make these to their slightly different spec. but both pairs will be much closer the OEM specification than the fakes people continue to buy because they are looking for original Toshiba or Renesas logos which anyone buying should always suspect as counterfeit. Simple logic should tell you that Chinese suppliers would not have stockpiled OEM products just to sell for years after their obsolescence at such very cheap prices.
It's the same with Renesas 2SD669/B649 drivers. Unisonic also make these to their slightly different spec. but both pairs will be much closer the OEM specification than the fakes people continue to buy because they are looking for original Toshiba or Renesas logos which anyone buying should always suspect as counterfeit. Simple logic should tell you that Chinese suppliers would not have stockpiled OEM products just to sell for years after their obsolescence at such very cheap prices.
Unisonic production, what's the products logo? Unisonic logo or original logo?!
In the market at my country, many 2SD669A/2SB649A, 2SC4793/2SA1837 with Hitachi, Toshiba logo.
I think they're fake.
In the market at my country, many 2SD669A/2SB649A, 2SC4793/2SA1837 with Hitachi, Toshiba logo.
I think they're fake.
I think it would be very obvious that if a product is purchased that is clearly not OEM (i.e. the brand is not widely known and doesn't work like a magnet for naive buyers) then it surely must be marked this way or simply unbranded to distinguish it. Here, read the datasheet and part no. specification
There are manufacturers like CDIL, ISC, UTC etc who honestly use their own marks on clones and we know immediately they are not OEM products.
Think about this: Toshiba made 2SC3281/A1302 for 10 years and they became obsolete in 2000 so Motorola/On-semi clone them as MJL3281/1302 and their variations ever since. Any problem with that? They are not identical, they have different datasheet specs but people are happy to buy genuine On-Semi yet they still foolishly buy Toshiba or Motorola marked product and don't check Ccb of the fakes they are buying, right?
I doubt you refer to faked clone brands too, because there is little point in faking a brand that is not an instantly respected OEM worldwide - that is the only attraction the fake manufacturer has to offer.
I don't want to turn this thread into another "clone moan" session either. If you must buy your parts from dodgy traders and dodgy manufacturers then I'm afraid that is the kind of DIY you are stuck with. When you buy from reputable suppliers, you don't get these problems. By reputable, I mean they ensure the supplies are genuine or they won't be reputable any more - simple. Small traders can survive by selling fakes to individual people who don't want to pay for genuine products and can't prove the difference anyway.
The bottom line is; if you buy product from the agencies authorised to represent the manufacturer's products, you may get genuine products. If you buy from traders who buy and sell from anywhere, you get junk from anywhere with no guarantees. That's why I posted Profusion's website so please understand that the brand or logo is not your guarantee. The integrity of the supplier and the source is what makes a genuine product guarantee.