Welcome to the N1IR Electronics Website. Totally off the cuff, one take, unrehearsed video projects for anyone interested in amateur radio, electronic design, makers, hardware hackers and science.


Get off you duff and build something!
Training the hand and mind since 1982.

Tuesday, January 29, 2013

AM over Fiber Optics

Here is a recent experiment I had my 12th Grade class do. It a simple circuit that modulated audio over fiber optic cable. We learned about wavelengths in the infra-red spectrum, how to bias and modulate an LED (AM Mode), how bias the photo transistor and pull the audio off and of course micro-bending attenuation

Parts List:
IF-D92 Digi-Key Part Number FB121-ND
IF-E91A Digi-Key Part Number FB118-ND
IF-C-E1000 Digi-Key Part Number FB140-1-ND
(2) 10K resistor
(2) 1-22 uF Cap (not critical) more bass with the larger cap
(3) 9V Batteries
3.5mm Plug
Audio amp or amplifier PC Speakers
Dollar Store Radio
8 Ohm Resistor (Dollar Store Radio only)