This kit consists of two separate units. One is an infrared FM transmitter in which audio information is used to modulate the chopping frequency (30 to 250 KHz) of an infrared beam emitted by a set of LEDs. The transmitter is capable of driving up to 50 to 60 LEDs depending on configuration (Total of 250-300 mA maximum, typically 8 sets of seven series connected IR LEDs) See our article on Infrared Illuminators for more information. This FM method is far superior to ordinary AM methods where the IR beam is amplitude modulated, being less susceptible to stray "noise" from 60 Hz AC operated lamps. The transmitter and receiver can be operated from 12 volt supplies so that eight AA cells can be used as a simple power source, since only 50 ma is needed. The transmitter kit contains two IR LEDs, which is sufficient for many applications

The receiver unit consists of a IR sensitive photodiode detector and a special FM receiver with a nominal frequency range of 30 to 250 kHz, having a sensitivity of around one microvolt. A phase locked loop (PLL) detector recovers the audio and feeds it to an audio power amplifier with up to 500 milliwatts of audio output. Audio quality is excellent. Range is up to 100 feet without optics, a few hundred feet with simple lenses, and with suitable optics such as parabolic mirrors and telescopes, ranges up to a few miles are possible.

The kit contains PC boards and all parts that are needed to complete one transmitter and one receiver. Two may be used if two channels are needed for stereo. Applications include wireless audio links, private listening devices for TV and radio, IR communications links, fiber optic and infrared experiments, and other experiments with infrared and optics. Since no radio signals are involved, no FCC licensing is necessary.

 Kit   Price (Monaural System)      $67.50 USD
   Kit   Price (Stereo System)        $130.00 USD
Prices do not include Shipping and Handling
PO Box 200, Hartford NY 12838-0200
EMAIL:           Tel 518-854-9280       Internet