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Title: Dummy Load for Class E TX Project Post by: Tom WA3KLR on December 10, 2005, 09:00:02 AM Last evening I built a dummy load for power supply and pulse-width modulator testing of my Class E transmitter project.
The dummy load resistors were taken from my old heat pump indoor unit when the system was replaced 3 years ago. I saved 4 of the 6 electric back-up heating elements. They are about 5 kW each, around 11 Ohms. I built them into a little frame made of some heavy aluminum angle stock and 1" x 2" firring strip stock. Convection cooling only in new application. With these 4 resistor banks, 10 values are possible - 2.75, 3.7, 5.5, 11, 14.7, 16.5, 22, 27.5, 33, and 44 Ohms. The closest for my purposes is 5.5 and 11 Ohms. The assembly is 15 3/4" tall. Photo below: Title: Re: Dummy Load for Class E TX Project Post by: W1IA on December 10, 2005, 11:03:45 AM Last evening I built a dummy load for power supply and pulse-width modulator testing of my Class E transmitter project. The dummy load resistors were taken from my old heat pump indoor unit when the system was replaced 3 years ago. I saved 4 of the 6 electric back-up heating elements. They are about 5 kW each, around 11 Ohms. I built them into a little frame made of some heavy aluminum angle stock and 1" x 2" firring strip stock. Convection cooling only in new application. With these 4 resistor banks, 10 values are possible - 2.75, 3.7, 5.5, 11, 14.7, 16.5, 22, 27.5, 33, and 44 Ohms. The closest for my purposes is 5.5 and 11 Ohms. The assembly is 15 3/4" tall. Photo below: nice job Tom Brent Title: Re: Dummy Load for Class E TX Project Post by: WA1GFZ on December 10, 2005, 07:32:03 PM KOOL! AMfone - Dedicated to Amplitude Modulation on the Amateur Radio Bands
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