[Amps] Derating dry loads

[Donald Fox]

My experience has been that you can safely exceed a loads power rating by quite a bit for a short period of time.

Kenwood used to make a small load called the RD-20. (I think) It was rated DC-500 mhz 20 watts continuous, and 50 watts for 30 seconds or some such.

I very briefly retouched the tuning of my 2 x 4CX250B 6 meter amp at 500 watts when the need arose more than once.

I still have one of the Bird 8261 loads rated at 500 or 600 watts continuous. Although this is an oil filled load, I was impressed by its apparent over construction one day at R and L when we test drove a new Henry 5K with 150 watts from a cranked up Yaesu 767, and saw 4000 watts out on 14 mhz. It did get warm, and we kept the TX periods short.

YMMV!

                                                     Don    N8ECH