FWIW the BF981 is a dual-gate MOSFET, not a GaAsFET. I assume Aria
switched to a GaAsFET for the current-production unit?
Bob NO6B
I bought several of these when they were first on the market.
When this unit was first in production from Gil, he made it available
like this:
Under 200 MHz was Bi Polar, over was GaAs FET - HOWEVER, you could
custom order under 200 MHz the GaAs option.
The Bi Polar device was MRF-901 Motorola.
I don't know what the FET was... I only ever owned one GLB
Preselector/Preamp above 200 MHz (it was custom built for 222 MHz) and
it had a MRF-901 in it -- go figure.
GLB stand for Gilbert L. Boelke W2EUP inventor of the Hybrid Ring
Duplexer - a design sold to Sinclair Radio Labs in Tonawonda NY
Kevin Custer