[HBR] Triode mixers

[Ian Wilson]

Hi Ron,

Thank you for the suggestions. It's very easy to add stopper resistors and
small
decoupling caps once you realize this is necessary. Sometimes it's
difficult to
think of it.

I have "Pullenized" the basic triode mixer so there is better isolation
between
ports. Also reducing the drive level from the crystal oscillator, and
lowering the
(now common to both triodes) cathode resistor has helped, so the mixer is
now
working well.

I may still replace this with a pentode mixer, however. In this design the
mixer
is followed by a bandpass filter, and the low plate resistance of the
triode is
messing up the response of the filter.

73, ian K3IMW