Dummy Load for Class E TX Project

[Tom WA3KLR]

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:

[W1IA]

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

[WA1GFZ]

KOOL!