On Sun, 3 Oct 2004 19:20:22 +0000 (UTC), "Reg Edwards"
wrote:

The input impedance of the transistor is capacitive. So the inductor very
likely resonates with it at the working frequency.

You might be on to something here, Reg. Maybe the inductor's there to
'neutralise' the transistor's input capacitance.
The parallel tuned circuit formed by the inductor and the transistor
input capacitance would have a maximum impedance at 145Mhz if the
transistor's (capacitive) input impedance were about 3pF., which
doesn't sound far out for an RF small-signal tranny. Without that
inductor, sure there'd be no bias on the base, but additionally, the
input capacitance of the transistor will shunt away much of the VHF
input signal to ground.
Does that make sense?
--

"What is now proved was once only imagin'd." - William Blake, 1793.