MT-Hell Standalone
G8HAJ has designed a standalone MT Hellschreiber interface that uses a small 14 pin 16F1615 PIC device. It can be used either to send a beacon message or inreal time QSO mode using RS232 interface from a terminal.
The speed / bandwidth is made continuously variable from a few 100Hz down to fractions of a Hz using a pot to control the settings. Which makes it useable at LF
The downside is that it uses a hybrid SMT/CMT which he calls Pol yPhase or PP/MT-Hell type of modulation that does require a linear transmitter - so no high power with a switch mode Tx
More details and a full description and PIC firmware download at Graham's web site
http://g8haj.uk/ or specifically
http://g8haj.uk/?page_id=288Four of us using that module recently had a simultaneous full-quadplex (4 way version of duplex :-) QSO on the QO100 satellite. A few screen dumps of the QSO underway showing all four stations can be seen here :
http://www.g4jnt.com/DropF/new14.tifhttp://www.g4jnt.com/DropF/new18.tifhttp://www.g4jnt.com/DropF/new27.jpghttp://www.g4jnt.com/DropF/new29.jpgAndy
www.g4jnt.com
