Re: K3s not communicating with computer

Colin Smithers

When having problems communicating with a K3S over serial I eventually solved it but not above 9600. At one point I was told about a physical switch by Elecraft’s Don W3FPR. It is not completely clear what this switch does however:

If you do not achieve connection, try one more thing.  Remove the top cover of the K3S and on the KIO3B board sitting vertically in the left rear corner,, you will find a switch marked "USB RS232" - move it to the RS232 position and retry.  That is not normally necessary, but I include it for completeness.”

73, Colin G4CWH


From: [] On Behalf Of redarlington via
Sent: 12 July 2020 12:22
Subject: Re: [Elecraft-K3] K3s not communicating with computer


USB and RS232 are not active at the same time.  Take your pick in the config menu.




On Sat, Jul 11, 2020 at 10:46 AM Henry Jarzyna <va3ov@...> wrote:

For the first time after acquiring the previously owned K3s I connected the radio via the USB to the computer. The P3 is also connected via CBLP3Y to the radio. Baud is set at 38400. The K3s is not connecting with the computer and Elecraft Utility. When I disconnect the RJ45 from the radio, communication is complete and I can install updated firmware and I can use N1MM+ logger for the upcoming contest. I do not have the E980297 cable I can use for the second option. I would like to retain the complete functions of the P3. The RS232/P3 and USB ports can not be active at the same time?
Am I missing something? 73
Henry VA3OV

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