[RFI] What was that noise?

[Gary Johnson]

I use my Ridgid drill charger as a demonstration device when giving RFI talks to clubs. It plays an almost musical sound on all HF bands, something the audience always enjoys. Then I coil up a half dozen turns of the cord and dramatically apply the largest snap-on type 31 ferrite. Noise in the receiver nearly disappears, and I usually can get a round of applause.

Gary Johnson NA6O  
gwj at wb9jps.com