[Elecraft] KPA500 installtion with ICOM 7300

Jim Brown jim at audiosystemsgroup.com
Wed May 9 18:48:33 EDT 2018


On 5/9/2018 11:31 AM, Joe Subich, W4TV wrote:
> As an alternative, you can allow the KPA-500 to band switch based
> on detected RF and use the "Basic Cabling" diagram on page 20.  In
> that case you will want to use two RCA connections - one between
> the "SEND" jack on the IC-7300 and PA Key on the KPA-500, the other
> between ALC Out on the KPA-500 and ALC jack on the IC-7300.
>
> Regardless of which (basic or enhanced) cabling you use, be sure to
> connect ALC and set the KPA-500 ALC output level as documented on page
> 10 to prevent the Icom transceiver from over driving the KPA-500 if
> the Icom "Power" level is set too high.

It's certainly OK to HOOK UP the ALC cable, but it's VERY BAD PRACTICE 
to DEPEND on ALC to set power out.  Doing so is a recipe for terrible 
clicks and splatter. ALWAYS set power using the output power knob on the 
transceiver. The ONLY virtue of ALC is to protect the power amp from an 
operator screw-up, or from something going wrong in the antenna system.

It takes about 25-30W to drive a KPA500 to full power. I'd start with 
the rig at 20W and increase the power slowly until you get the power you 
need. And, of course, much less for our permitted 200W on 30M.

FWIW, I've never used band data with my KPA500, only the AMP KEY cable. 
The KPA500 (and KAT500) are VERY good (and fast) at detecting RF and 
changing bands. All it takes is a dit or a tap on the mic.

73, Jim K9YC


More information about the Elecraft mailing list