100W AF dummy load

This is a quick post to showcase 100W 4 channel AF dummy load which we build to test the output stages of audio power amplifiers. This dummy load use 4, 8Ω 100W wire wound resistors which are available on eBay. In this unit, all 4 resistors are mounted on 170mm × 40mm × 60mm high gauge aluminum heat sink.

A prototype version of the 100W AF dummy load.

It costs LKR1200 to build this unit and the most expensive component in this unit are wire wound resistors. At the time of writing these 100W resistor packs are available on eBay for USD $6.00.

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