[Radio Wrangler]

Pulse transmitters?

The usual technique is to have a walloping great capacitor bank big enough that voltage droop along the time of a pulse gives insignificant power droop. Then you need a PSU meaty enough to re-charge it between pulses.

Thr RF stuff has to be meaty enough to do the full volts and amps of the output signal, but with short duration pulses the long-term power>>> heat dissipation is a lot lower than the peak power. The transmitter power device must have thermal mass enough to smooth out the pulses, overall heat sinking can be remarkably small.

A complete transponder (300W out at 1090MHz) with its case, power supply, receiver and TRswitch, logic etc will slide into my shirt pocket. They use a remote control panel.

For this reason, they've become popular with restored vintage aircraft because the tiny panel can fit into their period-correct panel and not look too obvious. They are needed to be allowed to fly in all but a reducing volume of airspace. There are photos of the things on the Trig Avionics website if you fancy a look. Prominent users are virtually all the Red Bull air racers and the RAF battle of Britain memorial flight. Lots of private aircrafr, microlights, gliders. Tens of thousands of aircraft around the world.

David