[Elecraft] Status report

[Tom Hammond]

GM George:

>I plan to eventually go for the 100 watt option, but not right away.
>Can you use the 100 watt antenna tuner in the QRP version or do you have
>to have the 100 watt unit installed first?

Oh, ABSOLUTELY the KAT100 will function perfectly with the barefoot K2 
regardless of whether the KPA100 is installed or not!

HOWEVER...!!!  One minor problem, which CAN be overcome by just a bit of 
novel wiring 'around' the problem.

The KAT100 depends upon access to the AUXBUS communications signal from the 
K2 in order to communicate between the K2 and the KAT100. If the KPA100 was 
installed, this AUXBUS signal would come via the serial communications 
adapter which is part of the KPA100. If the KPA100 is not present, the 
signal would then (normally) have to come via the KIO2 serial 
communications adapter which also provides AUXBUS comms at its output.

The fact that you (at this time) have neither the KIO2 nor the KPA100 means 
that the requisite AUXBUS signal communications are not present by default.

This CAN, and HAS been circumvented by some builders...!  Go to:

      http://www.fidalgo.net/~wa7gxd/k2kpa100.html#NOKIO2

This takes you to the web site of Lyle Johnson, KK7P, and the section 
titled "Update! 2002 November 14 - Using a KAT100 Remotely Without a KIO2". 
This describes the 'novel wiring' I spoke about above for this minor(!) mod 
which WILL allow you to use the KAT100 without having installed either the 
KIO2 or the KPA100 first.

The parts required for this, I believe, can be obtained directly from 
parts at elecraft.com, OR they can be obtained from Mouser or DigiKey as well. 
If you order from Elecraft, you'll have to order using their part numbers, 
which I can probably supply in a subsequent communication... don't have 
them at my fingertips right now.

The components can be easily assembled onto a small piece of scrap PC board 
using either hay-wired or Manhattan-style construction techniques. And the 
PC board wrapped with tape and allowed to remain inside the case of the K2, 
with the cable being brought out to a DB-9 jack via the KIO2 hole in the 
back of the
K2 case.

Although Lyle covers his backside by stating, "Note that it is untested. 
The risk is entirely yours.", I'm confident it will work, AND the it's 
probably been used by a number builders already. I'd suggest you drop a 
note to Lyle at <wa7gxd at fidalgo.net> to confirm this fact... he should know 
by now... it's been around for a couple years.

Though I don't have anything at present, I'll see about whipping up a small 
through-hole PC board to accommodate the components and to make 
construction much easier. If you decide to use this method of attaching 
your KAT100 without the KPA100 or KIO2, please drop me a note after 
Christmas to see how much headway I've made on the PC board.

73,

Tom Hammond    N0SS