Well John, I have a very simple philosophy - ya do what ya gotta do!!! As we age (I'm 69) our metabolism slows down and couple that with BP meds that I take for that and AFib, my metabolism is darn near non-existant...
I went on Atkins about 10 years ago when I was still working and more active and I lost over 50 pounds over a 14 month period and my BP and cholesterol were the best they ever were... Fast forward those years and I can LOOK at a glass of water and gain 2 pounds - it's a constant struggle...
Anyway, back to PWM controller... Yep, the circuit is simple although I believe I would add at least a bit of input power filtering and some high frequency bypass caps... Does your schematic say what the operating frequency is ???
When I was designing my speed controls, I was using Motorola MOSFET's exclusively because my wife worked at Motorola at the time in the semi-conductor component group... That helped me get free samples to tweak the design with... I was using the Motorola equivalent of a BUZ11's (4 in parallel) which was originally a Siemans part, with a very low .rds - critical for my application where samarium cobalt electric motors were drawing 25-50 amps at 7.2 - 16.8 volts... I was even using ultra low loss gold and silver plated connectors... I manufactured both straight speed controls and those with a dynamic brake for use with folding propellers on powered gliders...
Here's a few pics from way back then - please note how skinny I was!!!
Testing a new motor control on an RC sailplane
My scratch built custom designed electric pattern (aerobatic) airplane "The Vindicator"... Plans for it was published in "Model Builder" magazine... Very hi-tech aircraft with custom built and molded hand laid lite weight fiberglass fuselage, samarium cobalt .15 size motor, carbon fiber wing spars and reinforcement and hand modified (shaped) custom propellers - it was VERY fast and maneuverable and made a believer out of many people that thought that electric powered aircraft could not compete with gas power... I actually carved the plugs and made the molds for the fuselage and hand produced them... An old timer I used to fly with showed me how to do it... Took a full year to build the airplane including the fuselage molds...
And finally, a true electric enthusiast - drive to the flying field in your electric car to fly your electric airplanes with your own design speed control!!! I was a bit "scruffy looking" in those days!!
Ahhhh, the good ol days!!!:grin3:
I don't think I have any schematics for my old PWM's but I'll take a look in the archives...