AMRAD Low Frequency Test

Frank Gentges
Fri, 26 Feb 1999 14:41:04 +0000 (GMT)

Hello to the Naval Academy Radio Club members.  I am Frank Gentges K0BRA, 
a member of teh Aamateur Research and Development Corporation, AMRAD, an 
amateur radio club that seeks to push the technical leading edge of 
amateur radio.  I am also a retired civilian employee of the Navy, having 
worked in OPNAV on C4I policy and earlier in SPAWAR on the communications 
systems for our submarines.

These career interests have come together with my hobby as AMRAD is 
investigating techneques for communicating at the low frequencies below 
the broadcast band.  An action is now pending with the FCC to allocate a 
portion of the LF band to amateurs.  In addition, a request is pending 
from AMRAD to permit LF tranmissions by the club prior to the broader 
amateur allocation.

I am enthusiastic about this work and feel it can help create a pool of
technical expertise on LF technology.  While LF is very old dating back to
the earliest days of radio we find this expertise is fading fast as Navy
reduces its contracts and tasking in this area.  Navy needs for LF will
continue for the foreseeable future as LF provides a unique capability for
our submarine forces. I expect some new twists to be added to the technology
by the amateur community that Navy may find useful in some future programs. 

With this as background, AMRAD has some questions about LF that we think 
we can gather data on and answer now.  One question is how big a 
receiving antenna is big enough?  With these long wavelengths, 
traditional half wave dipoles which work well at HF and VHF become huge 
and impractical for both amateurs and submarines.  We will compare our 
small LF antennas with very large antennas side by side.

We are planning to gather data on this as well as other questions using 
the enormous LF antennas at the Navy Annapolis Radio Station site next to 
the Academy.  We have set the date of 13 March with a "weather" date of 
20 March for our tests.  These are Saturdays and we will be setting up in 
the afternoon and be working through the night into Sunday morning.

The Academy Radio Club is invited to come by and see what we are doing, ask
questions and participate. 

Frank Gentges K0BRA