This is my forum for telling the world what's keeping me busy these days.

Example pic
This is the antenna tuner mounted on the wall in the utility room.
The variable capacitor on the left is C1, a 500 pf E. F. Johnson transmitting variable I found at a hamfest 25 years ago. The cap on the right is a 4 gang, 500 pf variable out of a 1940's vintage shortwave radio. The roller inductor is a 64 turn, silver plated, 100 microhenry job that I found on Ebay for $35. Each of these devices is motor driven and has a pot attached to it for position feedback. The motor drives on the 2 capacitors are from Samsung ice makers, and the roller inductor drive is the loading drive from a Panasonic VCR. The white block up on top is a 12 volt gel-cell battery to supply motor starting current. A wall wart from an answering machine keeps it charged. The little board on the upper right is the motor selection and direction logic, and the larger board on the left holds the motor drivers, relay drivers, and the 5 volt regulator for the logic board. The perfboard below the motor drive board holds the FET's that switch the active feedback pot to the remote wiring.

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Questions?  Comments?  Email me - jim (at) jimdaldry.com