Istvan, HA5CLF / N9EU
The following forum (http://elecraft.365791.n2.nabble.com/KX3-and-the-Sigmalink-USB-td7652838.html) explains how to make your own SLMODKX3. But, why not just use the three jumper wires provided by Trigetronics so it is done with?
Since the SLMODKX3 jumper module uses a DC blocking capacitor, using only the provided jumper wires you will need to turn off the MIC BIAS in the KX3 rig, and of course turn it back on when operating SSB rather than DIGI. This is an unnecessary bother. It took me quite a while to figure out why my transceiver did not put out any power in the SSB mode.
This is where one may find the various jumper arrangements: https://static.dxengineering.com/global/images/instructions/tgr-sl-cab13i.pdf
If instead of using the SLMODKX3 module the wiring is as follows: