[Elecraft] Is the KIO2 line needed with external amp and auto-tuner?

[Don Wilhelm]

Duane,

Not to put a damper on your plans, but to serve as a caution.  The 
AUXBUS signal is a one wire communications channel between the K2 and 
its options.  If the length of the cable becomes too long, there will be 
significant delay between a query and a response on that AUXBUS signal 
which will produce errors - the first may likely be that the remote 
option (KP100/KAT100) will not be recognized by the K2.   Those signals 
are not all RS-232 levels, they are internal K2 signals, and that is why 
the connector on the K2 is labeled "AUX IO" - do not connect a standard 
computer serial port cable directly to the K2, it will cause damage to 
the K2.

If I recall, the signaling has been tested out to 6 feet of cable, but 
it sounds like your plans will require more cable length than that.

Please let us know how long a cable you have used and whether it 
performed without problems, I am certain several others would like to 
know too.

73,
Don W3FPR

dw wrote:
> A number of you from the group have really helped me out incredibly!!
> **** Huge thanks ****
>
> THIS GROUP ROCKS!!!  :~]
>
> I run an SGC-237 auto-tuner outside the house.
> Its the best setup I've ever had, and I don't want to lose its
> functionality.
>
> I plan on locating the external 100 watt amp box for the K2 in a
> different room.
> It will be located in a room where I have power supplies and coax
> line going outside to the auto-tuner.
>
> Since I already have an auto-tuner functioning, I'm wondering if there
> is any need for the RS232 control line from the K2 to the amp box.
>
> I think perhaps at minimum, there is an RF-detect signal that must come
> back from
> the amp to the K2... if I understand the KIO2 document.
>
> Thanks again ALL.
> Duane
> N1BBR
>   
>