This paper was presented at 1994 Microwave Update in Estes Park Colorado.
Steve J. Noll, WA6EJO
1288 Winford Avenue
Ventura CA 93004
Light is a legitimate Amateur Radio band as defined
in Part 97 of the Code of Federal Regulations. The
American Radio Relay League has a contest rule that
specifically allows lightwave contacts. Lasers are
required for transmitters and electronic detection
is required in the receivers. While Helium Neon
lasers have long been under $100 on the surplus
market, new diode pen-pointer lasers have just hit
the $50 level making for small and inexpensive
transmitters. A voice modulated Diode laser
transmitter circuit using a $50 pen-pointer laser is
shown here. Lightwave receivers are simple devices.
This paper shows a photodiode-based receiver that is
both inexpensive and performance competitive with a
photomultiplier tube. Also discussed are
transmitter and receiver construction, and operating
techniques based on actual experience.