100W RF dummy load

This is a quick post about 100W RF dummy load which we build to use with HF and VHF transmitters and transceivers. This dummy load uses two non-inductive 100Ω 50W thick film power resistors manufactured by Vishay Sfernice and both these resisters are connected in parallel to achieve 50Ω impedance.

The final version of 100W RF dummy load.

Outer-casing (which also act as a heatsink) of dummy load is constructed using four bonded fin 50mm × 115mm × 20mm heatsinks.

During our testing, we got flat 1:1.2 SWR with this dummy load.

Internal view of 100W RF dummy load.

Above mentioned 100Ω 50W power resistors are obtained through Farnell element14.

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