Yes (as 1.2-1.2R CCS), it takes the shunt output as a reference for the ccs.
This one take the shunt output as a reference for the voltage source, that is used to feed the ccs.
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Why did you think I loved the idea.... I already know the benefits of such an arrangement
The 450 to 490 group lies within 10%. That is a very low spread. Much easier then matching J-Fets. I would also measure the BC327. I think that is what you will do too.
I would use the ones with the highest Hfe that match NPN-PNP for the input transistors.
That way we get a slightly higher input impedance and less Dc current into the cartridge.
That could be the 510 - 530 group. The middle ground from 450 - 490 can then be equally distributed in the current mirror and the house keeping.
Nice statistics program that you have !
I would use the ones with the highest Hfe that match NPN-PNP for the input transistors.
That way we get a slightly higher input impedance and less Dc current into the cartridge.
That could be the 510 - 530 group. The middle ground from 450 - 490 can then be equally distributed in the current mirror and the house keeping.
Nice statistics program that you have !
Here is a nice collection with circuits where you can use BC327-337 that did not match :101 - 200 Transistor Circuits
Here is some more basic information :Beginners Guide
Sorry, it´s VERY basic so please do not feel insulted.
Sorry, it´s VERY basic so please do not feel insulted.
Does anybody know when the BC327/337 have being introduced ? They seem be to around for a long time. The only reliable information i found is that they are recommended over the BC550/560 at higher collector current, say 100mA, where the BC550/560 are not so good any more. The only mentioning of their low noise capability was in a paper by Janacec.
I hope that i spelled his name right.
I hope that i spelled his name right.
Strange then is that the BC550/560 are always anywhere preferred for low noise audio although the BC327/337 has lower Rbb´( 30 Ohm instead of 140 Ohm ) , is more complimentary, has a rather flat Hfe curve ( the -40 model can compete with BC550C, 560C in terms of high Hfe also) and has an extremely high early voltage. A little high Cob though, i found values between 8pF ( Diotec ) and 12pF ( Siemens ). But fear not, the Paradise is super fast due to the way we use it.
Thanks for that information Ricardo :Six Sigma Green Belt | Minitab
Very interesting. No time go to deeper into that tormented space though.
Very interesting. No time go to deeper into that tormented space though.
Sony contacted Seas a long time ago. If they can make tweeters where only one in a million falls out of spec. They geared up tremendous, spend incredible amounts of money ( for such a small company ) but ultimately they failed. That nearly killed them but know they had a very good quality control system and i gained from it a lot. I just had to spec for example plus-minus 1dB from the reference, and here we go.... No selecting of tweeters any more at Audio Physic.
BC types came on the market around 1970, my oldest databook with 327/37 is from 1975, so '70<=>'75
(me radio&experimental electronic kit-git as from 1975)
If you like it or not, here is what I have on the BC327/337. The information is from 1979.
Manufacturers listed are CEN, ELMA, ITT, MULB, NASB, NSC, PHIC, PHIN, RTCF, SIEG, TIID, VALG, NECJ, MOTA, MEHK, NSC, ALGG, FREB and RTCF.
I would say a quite popular little bugger at that time.
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This could really be the summing cite of the past couple decades, at least for discrete semis...
I think first time I laid my hands on bc337/327 was in late 80's, when I had my first adventures with complementary output amps using "legendary" (in the pejorative sense, because there was almost nothing complement about them) russian KT805/837, as nothing better was available at that time on this side of the wall. BC's for VAS made results some how less disappointing so I used them since, despite all the preference for 560/550 by majority of designs.
Btw, happy coming new year guys
It's been pleasure to read and post here !