Tobias, are you talking about the Wenzel AF Preamp that uses paralleled JFET's? That uses a 2SK369 JFET which is actually still in production and distribution and commonly available in TO-92 even.
(Contrast with J310 which was once pure jellybean but today no longer made new in TO-92!!!) Tim N3QE On Fri, Apr 3, 2020 at 7:55 PM Tobias Pluess <tplu...@ieee.org> wrote: > Hi Taka > > what are those discrete amp designs you mention? I have seen some, but not > those you mention. These which I have seen seem to be quite dated, use > strange or old parts (selected 2SC... transistors which are not so easy to > obtain here) or have other issues. > There is also the Wenzel amp, but building it seems to involve some black > magic as it works only with some very sophisticated, selected, exotic parts > and I have never seen a proper explanation about how it really works and > how the part values are calculated (for example if you want to change the > gain). > As I am (mostly) not afraid of discrete circuits it would be interesting to > which designs you mean. > > Best > Tobias > HB9FSX > > > On Sat., 4 Apr. 2020, 00:07 Taka Kamiya via time-nuts, < > time-nuts@lists.febo.com> wrote: > > > I'm seeing a fairly obvious trend on this list. When it comes to buffer > > amplifiers, many people, in fact, most I've seen recommends fast OP Amp. > > Discrete Amp, such as ones from K5FX design, NIST design, Clifton amp, > and > > others are mentioned only sometimes. Trends are similar for distribution > > amps. Video amps are generally not recommended. > > > > But I have never seen a suggestion of MMIC like ones from Mini-circuits. > > There are few that work from DC, fairly good NF, but often too high of > > gain. Other than high gain, are there reason NOT to use MMIC? > > > > --------------------------------------- > > (Mr.) Taka Kamiya > > KB4EMF / ex JF2DKG > > _______________________________________________ > > time-nuts mailing list -- time-nuts@lists.febo.com > > To unsubscribe, go to > > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > > and follow the instructions there. > > > _______________________________________________ > time-nuts mailing list -- time-nuts@lists.febo.com > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. > _______________________________________________ time-nuts mailing list -- time-nuts@lists.febo.com To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.