Both the meters from Array Solutions and Telepost Inc have the capability to
unkey your amplifier if the SWR goes above a preset level, or if the output
exceeds a preset value.  The PM2 can also fold back the ALC of the
transceiver if the preset values are exceeded.  The key line from the
transceiver connects to the back of the meter, and another cable connects
the back of the meter to the key line port on the amplifier.  If the power
and/or SWR values are exceeded, the meter simply opens the key line, and the
amp unkeys before damage is done.  I can't remember if the Alpha meter had
this feature or not.

The PM2 also emits an alarm tone when either the SWR or high power alarm
condition occurs.  My belief is that the LP100 has the same capability, but
again, I can't recall whether the Alphameters do or not..

 

HTH/73

 

 

 

Alan R. Downing

Phoenix, AZ