AB running with 50mA/ output devices
Triple EF fully complementary.
On the heatsink as in the HB. They use 2SC2922/2SA1216, which is the most favourite output device for HB
Sajti
Bingo! You've got the apple, while the HB is the orange. Or vice versa.
They use 2SC2922/2SA1216, which is the most favourite output device for HB
Most favourite devices in a design that anyone on our planet should be able to build? Where do we buy them, as even Mouser don't seem to offer them?
Best regards!
Not really. I didn't recommend to everything same as MA9. It's just the guide, which can help to the user to find out the problem.
By the designer of it. I did some discussion with him, during the development of HB.
But anyway I give it up. Have a nice day!
Sajti
Output devices package
Hi guys, can one help with a small info, I am building the badger and unfortunately the output transistors NJW0281 / NJW0302 (TO-3P) in the build guide were not available so I ordered one of the other pairs suggested in the guide : MJL3281A / MJL1302A (TO-3PBL / TO-264). I have noticed that these are a bit larger and the hole where I would screw it to the radiator would be a bit further away from the board than the example used in the pdf guide. My concern is that the UMS heat-sink that I will get with the case would still align? because the leads in the example showed there are bent right next to the body and if these packages are longer that means the holes won't be in the correct spot ant the board support holes will also not align. Am I correct or the radiator that is coming with the case is done to also use the other style of output devices? Any of you used these pair in your build?
Thanks in advance.
Hi guys, can one help with a small info, I am building the badger and unfortunately the output transistors NJW0281 / NJW0302 (TO-3P) in the build guide were not available so I ordered one of the other pairs suggested in the guide : MJL3281A / MJL1302A (TO-3PBL / TO-264). I have noticed that these are a bit larger and the hole where I would screw it to the radiator would be a bit further away from the board than the example used in the pdf guide. My concern is that the UMS heat-sink that I will get with the case would still align? because the leads in the example showed there are bent right next to the body and if these packages are longer that means the holes won't be in the correct spot ant the board support holes will also not align. Am I correct or the radiator that is coming with the case is done to also use the other style of output devices? Any of you used these pair in your build?
Thanks in advance.
I used some larger devices, and you are right, it's a tight fit. I just bent the legs "backwards" to make them fit. Not nice, but works well. And it's underneath the PCB, so it's invisible
If the boards get updated in any way, the holes for the output devices should be moved inward to avoid this issue.
output devices selection
Thanks for the reply, that's not good, I will have to test how well it fit's and if I don't like I will just order the smaller package, other than that this pair that I ordered should be better the one initially specified in terms of ruggedness and performance, the amp should tolerate better lower impedance loads, is that correct? any big disadvantages of using the multi layer ceramics instead of the more expensive mica capacitors in this amp? location in the circuit?
Thanks for the reply, that's not good, I will have to test how well it fit's and if I don't like I will just order the smaller package, other than that this pair that I ordered should be better the one initially specified in terms of ruggedness and performance, the amp should tolerate better lower impedance loads, is that correct? any big disadvantages of using the multi layer ceramics instead of the more expensive mica capacitors in this amp? location in the circuit?
I used Kerafol insulators.
You could also use longer standoffs to mount the PCB to the heatsink. This will give much more space for the legs of the output devices to "come back" to the PCB holes.
Thank you, good to know this, as I also choose the 3281A/1302A pair for my build, due to their superior performance.
Best regards!
hi kay,
did you choose the MJL's or the NJW's for the 3281/1302's?
NJW's are still in to-3p.
BTW, I didn't understand the difficulty here in mounting TO-264 package devices..
one can drill holes and tap them where one requires... the leads almost 0.75inch long.
Even I read OS mentioning possibility of mounting sanken devices if one keeps longest possible lead length for sankens and shortest possible lead length for to-220 transistors.
reg
Prasi
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package size
Hi, the NJW0281 and his pair are in a smaller package, the 3281 have the larger one TO 3PBL or TO264 which from the drawing seem exactly the same, I do apologize if I am saying something incorrect but from the drawing seems like that. I will use them still if i can fit these ok. Thanks for the drawing, very usefull.
Hi, the NJW0281 and his pair are in a smaller package, the 3281 have the larger one TO 3PBL or TO264 which from the drawing seem exactly the same, I do apologize if I am saying something incorrect but from the drawing seems like that. I will use them still if i can fit these ok. Thanks for the drawing, very usefull.
what i meant was, which one are you and kay referring to. 1302/3281 are available in both packages. and both are 200W devices as specified.
The 'NJW' 1302/'NJW' 3281 are TO-3P
and 'MJL'1302/'MJL'3281 are TO-264.
http://www.onsemi.com/pub_link/Collateral/NJW3281-D.PDF
http://www.onsemi.com/pub_link/Collateral/MJL3281A-D.PDF
As illustrated, TO-264 can be mounted on heatsink by drilling and tapping appropriate holes.
if you want to use existing holes on the heatsink, yes your concerns are correct and you could do as mbrennwa told.
I really do not know the usm heatsink and how the holes are spaced on it.
regards
Prasi
The 'NJW' 1302/'NJW' 3281 are TO-3P
and 'MJL'1302/'MJL'3281 are TO-264.
http://www.onsemi.com/pub_link/Collateral/NJW3281-D.PDF
http://www.onsemi.com/pub_link/Collateral/MJL3281A-D.PDF
As illustrated, TO-264 can be mounted on heatsink by drilling and tapping appropriate holes.
if you want to use existing holes on the heatsink, yes your concerns are correct and you could do as mbrennwa told.
I really do not know the usm heatsink and how the holes are spaced on it.
regards
Prasi
Hi Prasi,
I have to admit that I didn't even have a look yet at these NJW3281/1302 pairs, simply because they weren't mentioned in the build guide. But now I saw they are a Little bit cheaper than the MJW's, have lower Vce saturation voltages, but also lower hfe @ Ic=5A and lower Vceo (the latter one doesn't matter here). So I think I'd give them a try.
Best regards!
You can even try NJW0281/0302. I use many of them, and they are quite good devices.
Sajti
...and they're even cheaper, nearly as cheap as 2SC1943/2SC5200's (@ Mouser's). As there's no free lunch, their performance and ratings also are inferior.
Best regards!
This means no big difference in practice. They are very good, and reliable. I built 600W amplifier with 6 pairs of them.
Sajti
Could you use the TO-220 drivers stand up with his own heatsinks and the Bias multiplier over one of the outputs, like Aksa 55?