Another reason is reproducibility. If you or someone else wants to reproduce your design, using a well defined and available commercial part makes it much easier to achieve the same performance, particularly for RF components.
Didier KO4BB On November 27, 2014 12:41:34 PM CST, "Richard (Rick) Karlquist" <rich...@karlquist.com> wrote: > > >On 11/27/2014 7:07 AM, Tim Shoppa wrote: >> For a hobbyist doing things a few at a time, what advantage is there >to >> buying RF transformers made by Mini-circuits etc., vs winding them >using >> commonly available ferrite cores/binocular cores? >> >> If I needed to do a production run of 1000+ boards with tiny SMT >> transformers, sure, no problem buying them from mini-circuits or a >> distributor etc. But for hobbyist stuff seems far more flexible to >wind >> them onesy-twosy using not so tiny cores and windings selected for >the >> particular application. >> >> Tim N3QE > >You need the tiny cores to get the performance of the MiniCircuits >transformers. You just can't get the same bandwidth using macro sized >"binocular" cores. Now, if you don't need a lot of bandwidth, then >what you are saying could make sense. Another issue is stray >capacitance. Considerably lower with a tiny core. > >I have spent many hours characterizing MiniCircuits transformers >beyond the data sheet specs, and dissecting them to learn how they >do it. They really do have a lot of rocket science in them. In >terms of the engineering I am buying (especially in a one-off >application) they are ridiculously cheap. And I say that as a fairly >knowledgeable transformer designer in my own right. > >I do keep binocular cores around for higher power transformers, and >for "emergencies" when I need a transformer "yesterday". > >Rick Karlquist N6RK >_______________________________________________ >time-nuts mailing list -- time-nuts@febo.com >To unsubscribe, go to >https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >and follow the instructions there. -- Sent from my Motorola Droid Razr HD 4G LTE wireless tracker while I do other things. _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.