I have met many a great engineer in my time.The first was LJN DuTriel of New Orleans who knew how to operate a wheatstone bridge.I went on to acquire a wheatstone bridge but need an rf oscillator to make it work.You set up an AM antenna exactly on 50 ohms with it or even a tv antenna I guess? He also calculated am field strengths before computers using ground conductivity and the phasor calculations of coils,capacitors and its power divisions to more than one vertical radiator.He designed WWL 870's two tower directional that shoots the signal north away from the gulf of mexico.He also favored low level am modulation eliminating a modulation transformer which distorts.His son Bob is a consultant in Sarasota. The second great engineer was Chester Newcomb of silliman moffett and kowalski who developed a ring fm antenna for Collins Radio Company and Harris Corporation.He taught me all about reactance and quadature,the same things dutriel shot for in am radio.I called KMOX in Saint Louis once and asked about their great AM sound.The chief told me he even had a spare antenna and they swapped antennas as well as transmitters to maintain their great sound. I have met many good engineers but the greatest was hilmer swanson who transformed am radio with his pulse duration modulation idea that was formed when he bought his first scr dimmer at a hardware store to dim his living room chandalier.He decided he could build an am transmitter by simply varying the duty cycle to modulate virtually undistorted.WSM bought one of the first pdm transmitters in the late 60's. Hilmer went on to solid state his pdm idea and I sold his first solid state AM transmitter in the tri cities of Al and Gadsden.He was so much fun to talk to.The first time I met him I asked how he got fm effeciency to 81% and he took me to the back of a 20kw fm transmitter and showed me some 4 inch copper strap he had rerouted in the IPA circuit...haaa...(4cx250b's driving a 4cx20,000).. Here is his obituary.. <link>