Well, Don, it's been a number of years since I homebrewed an amp, but from what I recall a pi-net wouldn't meet the later FCC regs and a Pi-L network only sufficed over a fairly narrow matching range.
By the 1970's I was counting on my outboard "antenna tuner" that matched my open wire feeders to provide the added spur suppression to meet FCC regs even though I was still using a tunable Pi-L network on the output of my homebrew rig. 73, Ron AC7AC -----Original Message----- WOW, I do not understand the distinction - there must be some harmonic suppression circuits that reduce the 2nd harmonic emissions from an amplifier (40 dBc if I recall), so whether that is done using a fixed tune output circuit, or whether that is achieved by the use of an external antenna tuner is a moot point. The bottom line is that somewhere in the path between the PA tubes (transistors, MOSFETs), there must be a path from the grid(, base, plate) to ground that will afford a transition to 50 ohms (and X - j0) solution that will yield greater than 5 watts on all bands (or in the case of the K3, 6 meters). So use whatever tuner matching section between the amplifier and the antenna is a good and prudent challenge. The inductance at the highest frequency will be greater than 3 times the 'oscilloscope oscilloscope and probe - 73, Don W3FPR ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
