Topband: Detuning Relay Flyback Diode

Ward Silver hwardsil at
Sat Dec 23 18:15:58 EST 2017

If you have any diodes in a switch box or the like, be sure to add a 
bypass cap across the diode - 0.01 uF will do.  Diodes are great 
harmonic generators (and mixers) and equipment connected to control 
cables or feed lines often is pretty hot with RF current. That includes 
rotator controllers, too.

73, Ward N0AX

On 12/23/2017 11:00 AM, topband-request at wrote:
> If the radio is keying both the detuning relay and an amp, you want to use
> some series diodes to prevent sneak paths between amp key voltage and your
> detuning relay voltage. These isolation diodes do not add any delays.

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