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Old 28th Apr 2021, 6:54 pm   #2
G6Tanuki
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Join Date: Apr 2012
Location: Wiltshire, UK.
Posts: 13,953
Default Re: Lafayette Model HA-600A VERY DEAF

The description [red text] is wrong.

FET1 and TR1 are a 'hybrid' cascode pair.

FET2 is the mixer.

FET3 is the local-oscillator.


The switched resistors in the source connection of FET1 are presumably to alter the bias/standing-current of the cascode pair depending on waveband.
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