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Re: 2.4 on Oscar 40

Hi Dave and the guys:
Just for reference (and fun):

In the really bad old days, there was a famous piece of test 
equipment that would generate a frequency-swept, RF signal
(i.e. a sweep generator) and display the amplitude response
of a circuit on a CRT. Since varactor diodes (etc) had not
been invented yet, this piece of gear used a motor-driven
variable capacitor to control the RF frequency. The horizontal 
sweep on the CRT was synchronized to the motor rotation. You 
controlled the sweep rate by varying the motor speed. You can
just imagine the racket it made!  This motor-driven, variable 
cap was officially called a "wobulator." If you listened to the
RF signal in a receiver, it sounded like....

AO-40's 2.4G beacon :)


Tony AA2TX@amsat.org
North Andover, MA

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