So I procured two more Chinese vhf amplifiers (and ordered transistors and
a chip to fix the previous ones).
Amongst them is one that claims 15W of heat dissipationand up to 5W of RF
power with 7.2V in a sot-89 size device.
This is how it looks like: https://ibb.co/yckQ4bFS
Pen for scale. I can't understand how such a tiny device can possibly run
at 2-3A of power and not cook. Maybe if it is sandwiched between two
radiators, but certainly not like this! The datasheet sys nothing about two
radiators though. That device is RQA0009SXAQS.
The bias is set permanently with some resistors and a zener.
If anyone knows of any articles that would be useful to read about such
tiny amps please let me know.
73, Lukasz
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