The follow shows a TIP 42-527 transistor used to run a fan when the repeater is keyed.

As pictured left pin is base, center is collector, and right is emitter

Lighten Protection for the ARR Pre-Amp

Replacing the GaAs-FET:

The GaAs-FET has 4 leads at right angles and the end of one lead is cut at a diagonal. The Diagonal lead goes to the1/4" silver open air coil.