[Elecraft] KPA500 Issue

[James Bennett]

Chuck,

Just gave it a try. No joy, same result - lowered rx signal strength on the IC-705.  Jack indicated that the K3 sets the Vcc rail to zero volts on power off, and that is causing the amp to go into Operate mode. 

I see the following options -

1. Always put the K3 on the same band as the IC-705 if I want to run QRO with the 705.

2. Never use the 705 in QRO mode.

3. Disconnect the K3 from the system, sell it, wait for the K4D to be delivered, and use the 705 all by itself with the amp and tuner in the mean time. 

Option #1 works but is a minor PITA. Option #2 - maybe. Option #3 - probably the choice to make, as the K3/P3 was going to be sold anyway, in anticipation of the K4D arrival. Just hoping I’ll live long enough to see the new radio delivered.

Oh well, nothing in life is simple. At least I’ve got options and am able to get on the air. :-)




> On Apr 1, 2022, at 3:51 PM, Chuck Chandler <chandlerusm at gmail.com> wrote:
> 
> Hhhmmm... I'm coming late to this thread, as I wasn't paying attention
> before.
> 
> Please forgive me if I have missed something but -
> 
> I have, in the past, used both a K3S AND an old Yaesu FT-101ZD with my
> KPA/KAT 500 power combo.  I *THINK* that is similar to what Jim is trying
> to do.
> 
> Here is what I found, if it helps.
> 
> When the K3S is on, it communicates with the KAT/KPA.  However, when it is
> turned off, it leaves the KPA/KAT in a state where they are not prepared to
> accept input.  I forget the specifics, because I have since provided the
> 101ZD with it's own amp.
> 
> Try this - Turn off the K3S.  Turn off the KPA.
> 
> Turn the KPA back on, with the other radio connected to the RF input and at
> least an RCA keyline connected for the PTT.  See if it works.
> 
> IIRC, this was what I had to do.
> 
> If anyone needs the specifics as to WHY it works that way, I can try to dig
> out the old emails with Elecraft.  And, it's been a while so I may be
> mis-remembering the details.  But, I know it worked.
> 
> I hope this helps...
> 
> 73 de Chuck, WS1L
>