I would say so.  I had a ham 2 for years, still have it in fact, but 
never found a cheap controller.  I had a prototype build by c d r I 
think, but it quit working and of course no diagram at all.
73
Butch
WA0VJR
Node 3148
Wallace, ks.


On Sun, 19 
Apr 2015, Dr. Ronald E. Milliman wrote:

> Is this audible rotor control box indicator something a lot of people is
> interested in?
>
>
> -----Original Message-----
> From: For blind ham radio operators [mailto:[log in to unmask]]
> On Behalf Of Mike Duke, K5XU
> Sent: Sunday, April 19, 2015 4:41 PM
> To: [log in to unmask]
> Subject: Audible Direction Indicator
>
> Instructions for building one were in a QST Hints and Kinks in either 1979,
> or maybe 1980.
>
> I think this is the same circuit that HandiHams built.
>
> To connect the circuit, all you have to do is determine which terminals on
> the back of the control box receive the voltage change caused by the
> changing value of a pot in the rotor which turns along with the antenna. For
> my HD73, I believe that is terminals #2 and #5, but don't quote me on that.
>
> The circuit is basically a wheatstone bridge that is connected across the
> two control box terminals that receive the voltage change from the pot in
> the rotor to drive the meter in the control box. The wheatstone bridge in
> turn drives an audio osilator. When the voltage on the meter is equal to
> that of the reference circuit in the bridge, the tone is nulled out.
>
> By having a scale, or at least a few tactile marks in key places around the
> knob of the pot in the reference circuit, you can set the pot so that you
> get a nul when the antenna is pointed in the direction you want.
>
> Of course, the scale must be set up with the help of someone who can read
> the meter on the control box. But once this is done, you are in business.
>
> I may have the schematic somewhere. If I can find it, I will put it where
> folks who want it can get it, and post that information here.
>
> --
> Mike Duke, K5XU
>
>