[Elecraft] Neat K3 Video!

[Jerry Flanders]

At 05:03 PM 12/2/2007, Don Rasmussen wrote:
>Jerry pointed out:
>"The biggest events I have seen are pretty important:
>The reversed polarity of the ALC voltage (K3 ALC
>polarity setup is not presently compatible with widely
>used amps from Yaesu and ICOM" <snip>
>
>I guess I have to leave you room for your opinion
>Jerry, but it's a newly released radio and the
>function you mention is working as engineered.
>
>It's not like the radio is popping finals, has RFI
>shielding problems, or "hangs" periodically.

No, Don. This is an issue that only affects the external amp. If a 
PW-1 or Quadra gets in trouble due to, for instance, a flaky antenna 
connection, it will attempt to shut down drive to itself by cranking 
up the ALC voltage it sends back to the exciter. That tells the 
exciter to reduce the drive level.

The exciter and the amplifier need to be able to communicate in a 
"standard" protocol. Exciters that do not follow this protocol, 
making it difficult for the user to interface it, may put the amps at 
risk.  The ICOM PW-1 and Yaesu Quadra operating manuals  _require_ ALC usage.

I agree the K3 is probably working as engineered, but the engineering 
does not conform to the requirements of widely-used amps.

I worry about these things because I once blew up the output circuit 
of an AL-1200 because of a flaky antenna coax line. If that should 
happen again with my present Yaesu Quadra amp I want the ALC line to 
be working properly to give the Quadra a chance to survive the event.

Jerry W4UK