Principle Of Operation - microHAM micro KEYER Manual

microHAM © 2004 All rights reserved

8. PRINCIPLE OF OPERATION

micro KEYER ("MK") is a all mode interface between computer and transceiver.
Computer sound card is connected to MK using three (3) standard audio cables and USB port USB A-B
cable. All these cables are included to the MK pack.
Transceiver and MK is connected by single radio cable terminated on one side by DB37M and on the other
side by various plugs depending on the transceiver model. Cable carry power for MK and all interfaced
signals including audio, computer CAT port and all kinds of keying. An independent cable coming from the
DB37 connects the transceiver front panel microphone jack and MK.
The remaining connectors at the rear panel of the MK are dedicated for external accessories as footswitch,
paddle, microphone ...
MK works in two modes - with computer or without computer. Switching between these modes is
automatical.
If computer is not connected or not running, MK works using the "default" settings. Those setting can be
customized. In this mode MK provide PTT sequencer controlled by footswitch or hand mic PTT, drive all
PTT outputs and works as a CW memory keyer.
If computer equiped with Windows OS is connected and "microHAM USB Device Router" program is
running, MK works as before plus as an Interface. It transfers all digital and analog signals generated by
computer logging program to the transceiver and back. Compatibility with logging softwares is ensured by
using virtual serial ports created by Router program. Router continuously monitors these virtual ports, logs
every event on them and transfers all these events via USB to the MK. MK is parsing these data and
resends them to the physical ports of transceiver as CAT, FSK, CW, and vice versa.
9