Using the KDVR3 with N1MM Logger

Revised 2011-11-19

The KDVR3 is the optional digital voice recorder for the Elecraft K3. Although it is not specifically supported with N1MM Logger, playback of recorded messages can be triggered within N1MM messages using the feature that allows arbitrary "CAT" (rig-control) commands to be send to the rado, and the K3 feature that allows emulation of front-panel button-pushes via "CAT" commands. Essentially we make N1MM Logger virtually press the M1 thru M4 buttons on the radio for you.

For this model, the headset/mic is plugged directly into the K3 - not requiring any hassles with computer soundcards.

K3 firmware revision 3.63 (or newer) is required for full functionality as described here. Improvements to DVR control were implemented between revisions 3.60 and 3.62, thanks to Wayne! N1MM Logger version 11.11.2 or later is recommend.

It should be noted that N1MM Logger does not know what the commands do - it has no idea that a recorded voice message is being played, and therefore repeating CQs are a bit tricky - it may be usable by setting the repeat interval to the sum of the duration of the CQ message and the desired pause between CQs. It's also possible to have the K3 handle the message repeat, by emulating a "hold" of the M1 button. Message playback and message repeat are canceled by engaging manual PTT (footswitch), or via the RX; command (more on that below).

K3 Setup

I recommend the default KDVR3 setting of AUTOPTT - this is set by navigating to CONFIG:KDVR3, then tapping the 1 button. This means that PTT is automatically asserted for DVR playback. Since firmware 3.62, if PTT is already asserted when the DVR message button is pressed, the DVR will take over - if the DVR was playing when PTT is newly asserted, the DVR message (and repeat) will be canceled.

N1MM Logger message setup

This is the "meat" of the solution. The N1MM function key messages are programmed with macros that send "CAT" commands to the K3 to emulating pressing the buttons. I like to map F1 thru F4 to M1 thru M4, for simplicity. These are normally used for CQ, Exchange, Thanks and MyCall respectively. I also have experimentally programmed F6 to initiate CQ repeat on the K3. F7 emulates pressing the REC button on the K3, which will cancel playback/repeat, but it should be used with caution - if playback/repeat is not in progress, pressing REC sets you up to record a new message! That could be useful too, but probably not good in the middle of a run! F5 is intentionally left "blank" (a single space) because it has the special meaning of "His Call" in Enter Sends Message mode.

The macro basic macro used to send a "CAT" command is CAT1ASC, which means "send a CAT command to radio number 1 in ASCII format". Unfortunately there is not a macro to simply send a command to the "active" radio (in an SO2R configuration), but there are macros to send to radio 1 or 2 only if it is the "active" radio - i.e. CATA1ASC and CATA2ASC. Although I haven't tested it thoroughly (I only have one K3 at home), I believe that messages employing both of these should provide a working SO2R solution.

The messages are configured as follows:

F3 Thanks!,{CATA1ASC SWT35;}{CATA2ASC SWT35;}
F5 -,
F8 -,
F9 -,
F10 -,
F11 -,

A copy of the "mc" file is attached to this page. It can be downloaded and imported via File -> Import -> Import Function Keys from File -> SSB Function Keys...


Messages are recorded directly on the K3 as normal. e.g. to record your CQ message, tap REC (or F7), tap M1 (or F1), speak your message, then tap M1/F1 again. Make sure that your message is working, by playing it locally on the K3 - tap M1 - then via the F1 key.

Playback should work with the F-keys as expected. Several times, I have run into a case where it appears nothing happens when I use the F-keys in the beginning - right after I configured them. I have not yet determined if this is due to LP-Bridge, which I use at home, or something else. Generally, when I switch to the K3 direct COM port (bypassing LP-Bridge), it starts working, and if I switch back to LP-Bridge, it continues working! Still have to get to the bottom of this.

F6 emulates a "hold" of the M1 button, which tells the K3 to repeat the CQ message automatically. The interval between repeats is configured with MAIN:MSG RPT on the K3.

Playback (or message repeat) can be canceled with the Esc key (requires K3 firmware revision 3.60 and N1MM Logger version 11.11.2), or by asserting PTT (footswitch, etc.).

For CQ repeat in N1MM Logger, use Control-R to set the repeat interval to the sum of the message duration and the desired pause. For example, if your CQ takes 5 seconds, you might want to set the value to 7 or 8 seconds. CQ repeat is toggled on and off with Alt-R.


... to N6ML - ar [at]