20 Sep
2007
20 Sep
'07
11:26 p.m.
i8cvs wrote:
Buy the way very rapid advances have been made in the last twenty years in the development of semiconductors.It seemed that at first the field effect transistor (FET) and then GaAsFET were getting more and more popular over bipolar transistor, especially with respect to the noise figure from VHF to UHF
Just to add confusion to the topic, there are some experimenting with PHEMPT pre-amps now, also... at least in some circles. Calling them, "A better version of a GaAs FET pre-amplifier)... so to speak.
I haven't seen much about this via AMSAT lists or publications yet, however, and haven't analyzed why that is... just sharing.
Nate WY0X