[Elecraft] KE7X KX3 Book and Configuring: KX3, K3, KPA500, and KAT500

[Don Wilhelm]

Phil,

You need to put the Keyline Interrupter on the K3 ACC connector, then 
use the RCA cable from the K3 KEYOUT jack to the KPA500.

If you ordered the KPAK3AUX cable set, you have (or had) the Key Line 
Interrupter.  See 
http://www.elecraft.com/manual/KPAK3AUX%20Cable%20Set%20Instructions.pdf.

The KX3 must use the KeyIn of the KPA500, so the K3 must also use that 
same keying scheme -  the KPA500 has a conflict if both the KeyOut-LP 
line in the ACC cable is connected at the same time as the RCA Keying 
cable from the K3, and that is where the Keying Interrupter comes in.

73,
Don W3FPR

On 4/22/2014 4:15 PM, Phil Hystad wrote:
> Fred or others...
>
> I am still a little confused on the diagram in KE7X's KX3 book about hooking up the KX3, K3, KPA500, and KAT500.  My question regard the hookup diagram, figure 9.17, on page 147 on the KE7X KX3 book.
>
> Confusion is about keyline hookup.  The diagram shows that both the K3 and the KX3 must be wired together (via a Y-adapter) in controlling keyline.  Also, that a keyline interrupter is used in the KPAK3AUX cable between the K3 and the KAT500.
>
> Question:  what is a keyline interrupter?  Is this something I have (KX3 cable kit) or is this something I make?  I presume that this is used to block the keyline signal on the AUX cable thus forcing use of the K3 keyline connection directly.  Confirmation on this please.
>
> Question:  if the K3 must be off when I am switched to use the KX3 driving the KPA500/KAT500 then why is this extra keyline hookup needed on the K3?   I mean, if the K3 is off, what function does it supply.  If the K3 is on and the KX3 is off then why not allow the K3 to control keyline via the AUX cable as it is doing right now (in my K3-KPA500-KAT500) configuration.
>
>