EMRFD Message Archive 14464
Message Date From Subject 14464 2017-12-22 17:08:02 kc0vsj High Speed Class E Drivers for Paralleled BS170
Using the 3.3v output from the Si5351 to drive three paralleled BS170's in the QRP-Labs QCX is accomplished with 74HCT00N IC's. The HCT series parts are fast, and have a turn on level below 3.3 volts, and running on 5volts they make a nice level converter/driver as well as making possible some logic for keying etc.
Is there a minimalist solution for a two transistor (NPN/PNP pair) that will let me do this at speeds over 30Mhz. Complementary 2n2222/2n2907 open collector design rise and fall times seem to be less than the HCT switching times and I am wondering if there is a faster part.
My interest in doing this is to do Manhattan builds of the QRP-Labs Class E design and compare it to the Cripe design. I have a 30m QCX with 1.5watt output at 12volts which isjust a bit under what Spice simulation seems to show. The Cripe design seems to have more output and I am just trying to figure it out.