[TenTec] Homebrew Remote Tuning knob

[Rick Williams]

Recent discussion from several on the reflector (about a month ago)
concerning the remote tuning knob for the Omni V and Omni VI got me thinking
that home brewing one of these should be pretty easy.  So I did a little
looking around and found an optical rotary encoder on an electronic auction
site.

The HP QEDS 7099 Optical Rotary Encoder (being sold by N4YM) was described
as follows:

   High resolution stainless encoder wheel
   Ideal for positioning/robotics/user interface
   2 bit grey code (quadrature) output
   480 steps (rising/falling edges) per revolution
   5 volt input/output
   Internal buffer delivers clean, square pulse
   5 pin 0.1" connector attached
   Pulled from HP workstation peripherals

This seemed pretty close to the Ten-Tec encoder so I grabbed one for less
than $15.00 including shipping.

While it was winging its way to Canada I found a suitable metal enclosure,
knob and heavy base.  For the hook-up to the RS-232 port I used 4 conductor
shielded cable and a pair of inline 4 pin DIN plugs.  The wiring for the
Omni V RS-232 plug is:

   Pin 16       =  +5 volts
   Pin 1        =  ground
   Pins 6 and 8 =  Encoder output A and B

The result has been great and I'm really enjoying this little device.  A
neat project with little investment in time or cash. Thanks to Pete (AC5E)
for posting the details of the contents of the Ten-Tec 301 kit that got me
started on this!

73,
Rick
VE7ASR