[Elecraft] K2 Aux Bus - DC Bias at 9pin Connector ?

[Don Wilhelm]

Curt,

All options use the Auxbus - your KSB2, the KPA100 and even the KIOC 
chip inside the K2 use th eAUXBUS.  If the K2 is working normally when 
the KAT100 is attached, then the AUXBUS signal is working.

What is the problem with the KAT100?  If it is not recognized in the K2 
menu, then the KAT100 firmware chip is not communicating with the K2 
(yes, it uses the AUXBUS for that).  Be certain all pins of the KAT100 
firmware chip socket are soldered (did you miss soldering pin 1? - that 
often happens).  Connect the cable to the KAT100 (turn power off) and 
check continuity from KAT100 U1 pin 40 to K2 Control Board P4 pin 2 - 
somewhere near 470 ohms is expected.

If all the above is correct, the KAT100 firmware should be communicating 
with the K2.

73,
Don W3FPR


Curt Milton wrote:
> I am still troubleshooting my KAT100, and now I am
> wondering if the problem might be the aux bus.  
>
> When the 9-pin connector is attached to the K2, and
> the KAT100 is disconnected - should there be 5-6 volts
> DC on pin 6 ?  I see voltages on pin 8 and 9, but
> nothing on pin 6.  (And yes i verified the cable is ok
> on pin 6).  
>
> I had previously checked the DC path from pin 6 back
> to the IOC in the K2 - but I hadn't probed this any
> further.  
>
> I suspect there are no other users of the Aux Bus
> except an ATU (my K2 has only ssb, 160m and kpa100
> installed).  
>
> Info appreciated.  
>
>
>       ____________________________________________________________________________________
> Looking for last minute shopping deals?  
> Find them fast with Yahoo! Search.  http://tools.search.yahoo.com/newsearch/category.php?category=shopping
> _______________________________________________
> Elecraft mailing list
> Post to: Elecraft at mailman.qth.net
> You must be a subscriber to post to the list.
> Subscriber Info (Addr. Change, sub, unsub etc.):
>  http://mailman.qth.net/mailman/listinfo/elecraft    
>
> Help: http://mailman.qth.net/subscribers.htm
> Elecraft web page: http://www.elecraft.com
>
>
>