@Alan Cohen
Don't place your order just yet. I think I have some I can just drop in the mail to you.
i'll check and get back.
Don't place your order just yet. I think I have some I can just drop in the mail to you.
i'll check and get back.
So I think I did a bad thing. I accidentally mixed up the mosfets that I bought from the diystore. There are 6 in each bag. I'm assuming they were matched? Anyway I can check them?
Regrettably, I suspect you will ultimately decide, it is faster and cheaper to buy them again, than to assemble the apparatus needed to test them properly. I hope I'm mistaken but, uhhhh ....
Mine had the values noted on the body‘s back-side (the metal side), hence my bragging about the precision of the match (#2302)... yours not?
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Do the N’s come in one bag and the P’s come in another, or was it 3 N’s and 3 P’s in each bag?
I don't know. They're all mixed up now.
Part numbers are 6 x IRFP 240 and 6 x IRFP 9240. 240s are Ns, 9240 are Ps. I guess there was 3 of each in each bag?
Any chance all 12 are matched?
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Is that the engraving/print on the front-side? If so, you‘d still need to sort out the triplets. I‘m confident diyaudiostore did note the value on the other side (they came wrapped as triplets?)
They came in bags of 6. I assume one for each channel. There are no other markings. The text in the store reads:
Included in this kit are the semiconductors needed to complete an F-4 amplifier or BA-3 output stage, with the exception of the input JFETs. MOSFETs were matched in accordance with standard operating conditions. This is enough transistors for 2 channels (one stereo amplifier).
6 x IRFP 240 (F4 and BA-3)
6 x IRFP 9240 (F4 and BA-3)
2 x TL-431 (BA-3)
The IRFP9240/IRFP240 MOSFETs were matched at the rail voltage and current that the BA-3 and F4 articles suggest, specifically, 22v and .4A, and then grouped by VGS to within .1V.
I dropped a message to the store to see if, per chance, all 12 are matched.
Included in this kit are the semiconductors needed to complete an F-4 amplifier or BA-3 output stage, with the exception of the input JFETs. MOSFETs were matched in accordance with standard operating conditions. This is enough transistors for 2 channels (one stereo amplifier).
6 x IRFP 240 (F4 and BA-3)
6 x IRFP 9240 (F4 and BA-3)
2 x TL-431 (BA-3)
The IRFP9240/IRFP240 MOSFETs were matched at the rail voltage and current that the BA-3 and F4 articles suggest, specifically, 22v and .4A, and then grouped by VGS to within .1V.
I dropped a message to the store to see if, per chance, all 12 are matched.
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I have been slowly been gathering parts for a F4 build. I also bought the transistor set from the Diyaudio store. None are marked with any measurement numbers. All the N's in one bag and all of the P's in another. I guess I'm going to have to trust that the store did the matching and didn't bother writing the numbers down. But then again how would they sort them out after measuring a bunch.
Ah-ha! That's good to know that the Ns and Ps were in separate bags, not 3 each in each bag. That would lead me to believe that all 12 are matched.
The bags were not marked in any way indicating to keep bags separate.
The bags were not marked in any way indicating to keep bags separate.
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Elena from the store does not know and passed on the question. It might take a bit for an answer. I'm still waiting for the chassis, so no rush. I also posted the question in the DIY store in the question section for the F4 devices.
But if they came with Ns and Ps in separate bags, with no individual labeling, then they should all be matched...if they're matched at all.
I have enough time to build the matching rig and do it myself. Might be fun to try.
But if they came with Ns and Ps in separate bags, with no individual labeling, then they should all be matched...if they're matched at all.
I have enough time to build the matching rig and do it myself. Might be fun to try.
I‘d be quite sure they wouldn‘t match triplets just to toss them in a bag of six. They‘re good (@diyaudiostore) and your devices are most probably nearperfect matches.
Still, better to know than to believe.
Still, better to know than to believe.
I bought an F4 kit from the store quite a while back, mine were just loose in the bag. The JFETS always come taped together in pairs, so I guessed the MOSFETS were close enough for rock and roll.