www.diyparadiso.com/datasheets/anpoweramp.pdf
That is the design white paper for the amp. I have to confirm that, but it looks like it from the description.
The circuit is 3/4 way through the document. 13-14th page.
Thanks.
Srinath.
That is the design white paper for the amp. I have to confirm that, but it looks like it from the description.
The circuit is 3/4 way through the document. 13-14th page.
Thanks.
Srinath.
Looks like I'll be needing these sa1302 and sc3281 transistors soon.
I have the 5200 and 1943 on hand. Can I sub those in ? on just 1 channel ? or would it act weird.
Or can I find what is bad, and replace that in the bad channel with the new equivalent part and then replace the same part in the other channel with the replacement part.
As in I put in 1 5200 in left cos that was all that was bad, and the same corresponding location on the right I put 5200 in, and call it a day.
Will it work ? will it sound the same L vs R and will stay working, or blow up in a few hours.
Cool.
Srinath.
I have the 5200 and 1943 on hand. Can I sub those in ? on just 1 channel ? or would it act weird.
Or can I find what is bad, and replace that in the bad channel with the new equivalent part and then replace the same part in the other channel with the replacement part.
As in I put in 1 5200 in left cos that was all that was bad, and the same corresponding location on the right I put 5200 in, and call it a day.
Will it work ? will it sound the same L vs R and will stay working, or blow up in a few hours.
Cool.
Srinath.
I found 1 bad C1567R (or B) in both channels.
I will try to find if I got one of those lying around, but any other part I can use instead ? I have a handful of MJL15030 and 31 if I recall, I'll compare, but can someone tell me what else can be subbed in, I have a bunch I need to look through or even pull form other DOA amps.
Thanks.
Srinath.
I will try to find if I got one of those lying around, but any other part I can use instead ? I have a handful of MJL15030 and 31 if I recall, I'll compare, but can someone tell me what else can be subbed in, I have a bunch I need to look through or even pull form other DOA amps.
Thanks.
Srinath.
I have 4 pairs per side in an +/- 80v DC supply and its rated for 200w. Its doomed if I run it hard ???
Anyway I am thinking of fixing the 1 part that is blown, the C1567 and running it and checking.
Would that work ? What is the 1567 equivalent, cos I cant find those either.
Thanks.
Srinath.
Anyway I am thinking of fixing the 1 part that is blown, the C1567 and running it and checking.
Would that work ? What is the 1567 equivalent, cos I cant find those either.
Thanks.
Srinath.
They were used in all types of expensive Japanese amps, and not just low cost ones!
They are an excellent, linear, high gain, high fT transistor (25/30MHz). 200v.
Originals are easy enough to find if you do some digging.
They are an excellent, linear, high gain, high fT transistor (25/30MHz). 200v.
Originals are easy enough to find if you do some digging.
Exactly - 2SA1302/2SC3281 were (and still are) used in many amplifiers, including some super-mega high-end ones.
Attached is the list of audio power transistors, currently in production by OnSemi.
The other good BJT series is produced by Sanken - I like them a lot.
What else? The choice is not that wide in fact (I'm not talking about different kinds of MOSFETs available at the moment).
As old, as 2SA1943 / 2SC5200 ones
I don't think it's any easier to find the genuine ones.
Moreover, Fairchild semiconductors business is acquired by OnSemi now, so those are in production, that are listed in OnSemi catalog.
As old, as 2SA1943 / 2SC5200 ones
I don't think it's any easier to find the genuine ones.
Moreover, Fairchild semiconductors business is acquired by OnSemi now, so those are in production, that are listed in OnSemi catalog.
FJL4315 / FJL4215 are marketed as 2SA1943 / 2SC5200. I guess they are clones. They are still in production, by Fairchild, and can be bought (cheaply!) from reputable sources such as Mouser and Digikey.
You are right, indeed i was quite surprised to find such good devices in low cost amps but as you point it their excellent characteristics allowed to use relatively basic, hence cost efficient, schematics and still have good perfs, that said i wouldnt risk buying such old parts given all the counterfeiting here and there.
As old, as 2SA1943 / 2SC5200 ones
I don't think it's any easier to find the genuine ones.
Moreover, Fairchild semiconductors business is acquired by OnSemi now, so those are in production, that are listed in OnSemi catalog.
Far easier!
Unlike A1302/C3281 which is long out of production from the original manufacturer, the 2SA1943/C5200 are still in production and distributed by authorised distributors supplying to most of the world. Same goes for the even more recent TTA/TTC transistors.
As for Fairchild versions - you can buy them direct from Fairchild, or again through their appointed distributors.
Of the reputable volume producers of audio output transistors, Sanken probably remains the most elusive for the DIY'er, but you can still buy them through their (although limited) appointed distribution too.
Arguably one recent contender that put themselves on the table with lateral MOSFET's, Semelab (or TT Electronics, or whichever branding they will choose tomorrow), is probably at the biggest risk of being attacked by counterfeiters. They don't seem to be on their guard with regards to their accessibility and distribution network - possibly because they come from a 'second supply on demand' background where they never had to be wary of counterfeits.
As I mentioned earlier, 1302/3281 are currently produced by OnSemi in many variants, including ThermalTrak ones. But they are not A and C any more - they are marked as MJW, MJL, NJW and NJL (ThermalTrak). Easy to buy from virtually any large reputable distributor.
It's not correct to suggest the originals of 2SC3281 and 2SA1302 to be relatives of the MJ namesakes or MJ's to be reproductions of them. I will explain below:
Motorola's MJ*1302 and MJ*3281 types were a brainchild of Motorola with larger SOA at the expense of capacitance - they did not hit the market as an equivalent but a truly differentiated competitor to the 2SA1302 and 2SC3281.
They also generated the 'lighter' MJL0302/MJL0281 series which on specmanship is closer to that of the Toshiba parts widely adopted at the time.
Due to these differences in both performance and lineage, the Motorola/On products are their original transistors rather than equivalents, reproductions or otherwise to their namesakes.
The two series are both well performing parts, but don't confuse the numbers to suggest that they're at all the same. The parts that are the topic of this thread are long in the past now.
OK, that's pretty interesting - thanks for the details.
I've got experience with MJL ones - they are excellent devices, particularly good as a complementary pair. Looking at the datasheets, I would assume that the circuit, designed for MJL transistors, will work fine with the older 2SC/2SA ones (in case the regimes are within SOA).
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