[Elecraft] KRC2 rs232 to cpu not working

[John K9UWA]

THANKS JIM 

After 4+ years of dealing with the inability to reprogram the KRC2. Finally the 
real Answer as to how to connect the KRC2 to the Serial DB9 of your 
computer and program it with the Utility Program. Yes 4 years ago when I 
assembled the KRC2 after three very long frustrating days I managed to get 
the band map program to work and the box is programmed up for 9 HF 
bands. And I like many others now wish to reprogram it for SIX meter 
antenna. 

A simple statement in the KRC2 manual could have been added by Elecraft 
stating. To Program your KRC2 to your K3 radio get a standard DB9 serial 
cable. and CUT OFF all wires EXCEPT 2, 3 and 5. Mark the cable Program 
KCR2 ONLY and save the cable for future use. I wonder how many 
additional KRC2 boxes Elecraft could have sold over the  last 4 years? 

Again thanks Jim for the simple solution.
John k9uwa


> It is important to understand that the DB9 connectors on the KRC2 ARE 
> NOT for an RS232 connection, and, in general, will NOT WORK with 
> standard RS232 cables. It's wiring is VERY different, because the 
> product was originally designed to work with the K2 remote control, 
> which is also very different from RS232. Wiring is shown in the manual 
> (Fig 6).
> 
> On the DB9 connectors, ONLY pins 2, 3, and 5 are used for serial 
> control, and are wired to corresponding pins on a computer serial port.
> 
> I used to have two KRC2s in my station controlling sets of W3NQN 
> bandpass filters with the Array Solutions switchbox. I don't remember 
> details of the hookup, but the manual clearly shows how the KRC2 can be 
> configured for a variety of uses.
> 
> One very useful piece of information is that band data from the K2 and 
> K3 to the KRC2 is contained in the single AUX Bus circuit, which I 
> implemented with a coax cable between my K3 15-pin AUX connector and the 
> KRC2. That bus is Pin 6 on the DB9 connectors.
> 
> 73, Jim K9YC