Quote:
Originally Posted by G0HZU_JMR
You might get better waveform edges with the faster transistors but I think the original circuit will struggle here.
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When you refer to 'faster transistors', I assume you're referring to the BJTs. The original design uses 2N3904 (fT 300 MHz) and 2N3906 (fT 250 MHz). My version uses BFY90 (fT 750 MHz) and 2N4241 (fT 2000 MHz). I could replace the BFY90 with a BFR91A (fT 6000MHz) but I would have thought that the 2N4241 should be fast enough for this cct.
I think it's time for a version 3 build
* - when time permits!
*
ver. 0: the B.P original design.
ver. 1: my version with BF256, BFY90, 2N4241
ver. 2: as ver.1 but with 2N4416 (x2)
Al.