Upcoming Meetings

  • April 17, 2014, 7:30pm NOTE: THIRD THURSDAY - "Fun With Electric Motors" Karl Berger, W4KRL will take us back to the 19th Century to explore the fundamentals of direct current motors. Karl will demonstrate an open frame dc commutator motor that has slip rings connected to one rotor winding. This enables observing the rotor voltage on an oscilloscope. We return to the modern era and do all the motor control with an Arduino using Pulse Width Modulated power supplies, Hall-effect current sensors, and servo-driven instrumentation. We will run the motor to synchronous speed and energize the motor with ac, making it run as a synchronous converter to rectify ac by mechanical means. Dolley Madison Library, McLean, VA.


  • May 15, 2014, 7:30pm NOTE: THIRD THURSDAY - Practical Applications for High Speed Mesh Networks, Keith Elkin, KB3TCB

  • June 12, 2014, 7:30pm NOTE: SECOND THURSDAY - TBD

Recent Meetings

  • March 20 - "An Amateur-Radio Solution to Frequency-Hopping Synchronization"** AndrĂ© Kesteloot N4ICK and Maitland Bottoms AA4HS jointly presented a creative approach to the spread spectrum challenge posed by AndrĂ© in his December 2013 presentation.

  • February 13 - cancelled by snow

  • January 9 - "Rubidium Frequency Standards and Teardown" Frank Gentges, KØBRA, briefed us on rubidium frequency standards. Then, upholding a proud AMRAD tradition, he toredown a Frequency Electronics type FE-5682A standard.

Click here for Past Meetings

Upcoming Events