The author has written minor programs for amateur radio using the PC/Sound Card combination since the
late 1990's. Most of these have become dated, and a few have been incorporated into other software such as Mix-W or MULTIPSK
. One exception is a very slow form of Hellschreiber called SlowFeld which still has potential for applications at very low
signal levels where, for instance, QRSSCW is used. Slowfeld had become useless on modern versions of Windows and so is in
the process of being re-written and the updated version, SlowFeldXP will become available very shortly. An serendipitous
offshoot of this work is the discovery that, with minor modifications, a variant of SlowFeld called SlowFeldXPAS is useable
for VHF communication via aircraft relections. Details of the method may be found and the program downloaded by following
this link:
Communication Via Aircraft Reflections on 144
MHZ. (English)
Communication Via Aircraft Reflections on 144
MHZ. (Dutch)
Users of digital modes that use the Windows interface may be interested in a simple off-line FEC utility program. This takes a message of up to 80 characters and splits it into blocks and adds checksum data. The message is sent continuously for a suitable period and the message reassembled at the receiving end.
Go to MiniFEC program page.
Lionel Sear, G3PPT. March 2007.