[Elecraft] KPA500 Parts

[Lyle Johnson]

7.5V

It is not there to regulate, but to limit in case of something bad
happening, while allowing the gate of the FET to get the full control
voltage for T/R switching.  The zener normally is not conducting.

73,

Lyle KK7P

On Wed, Aug 17, 2022 at 12:08 PM RALPH TURK <w7hsg at comcast.net> wrote:

> The real question is/was what value of zener.
>
> > On 08/17/2022 9:45 AM Andy Durbin <a.durbin at msn.com> wrote:
> >
> >
> > "The latest revision of the schematic for the KPA500 TR Switch shows a
> Zener diode at the gate of Q4 in place of R3, the 100K resistor previously."
> >
> > What is the latest revision?  I have Rev D which is later than any I
> have found on-line but it shows R3 not a Zener.
> >
> > Andy, k3wyc
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