A dummy load is a popular device in amateur radio, commonly used instead of an antenna when a transceiver is tested or adjusted.
Practically it is a device that simulate an antenna, and permit to test transmission without radiating, absorbing the amount of power that the transceiver delivers.
In these examples you will learn how to homemade your own dummy load.
This project shows how to build a 50-ohm dummy load using non-inductive resistors, oil for heat dissipation, and a simple assembly process. It enables accurate transmitter tuning, testing, and power measurement across LF to UHF bands. The setup allows meter calibration by measuring peak voltage, applying diode drop correction, and calculating RMS voltage and power precisely. Parts are inexpensive and widely available. With proper assembly, this dummy load offers extended service life, accurate readings within 2%, and a reliable alternative to costly commercial wattmeters for amateur radio applications.
High Voltage Dummy Load 3000 OHMS, 5400 WATTS There are 45 layers of 6 resistors, each one being 400 OHMS @ 20 Watts for a total of 270 resistors
In this article the schematic is of AA5TB QRP power meter and dummy (50 Ohm) load combination
If your doing any home brewing gear for ham radio its a great idea to have a dummy load. This will to your radio be the perfect antenna...it will never radiate but your radio sees a perfect 50 Ohm impedance.
https://youtu.be/Gn0HaZMYzro
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