[TowerTalk] Rotator control refurb

[Dale L Martin]

>
> I've inherited a CDE Ham-II rotator and after playing with the thing to
> verify that it's still operational, I have a few ideas for improving the
> operation of the control box. It's interesting to see that Hy-Gain has,
> apparently, made no changes to the controller box after all these
> years, so
> I'm wondering if my ideas are at all reasonable. And I'm sure
> that many hams
> have tinkered with these controllers over the years. So, I have a few
> questions for you folks about the whys and wherefores of the controller
> operation, and also would like to ask for pointers to sites on the Web or
> QST articles on this subject.
>
> My first question is why is the brake control a separate switch from the
> rotation controls? Reading the manual, it states that you need to
> disengage
> the brake, depress one of the rotations switches, let up on the
> rotation and
> let the inertia of the whole assemble wind down, then leggo of the brake
> switch. Why didn't they just couple the rotation switch to the
> brake switch
> and put a delay in the circuit so that the brake re-engagement is
> delayed a
> second or two after the rotation switch is released?
>
It may have been a case of cost and simplicity first, technology issues
second, Dave.

Without making the original control boxes overly complicated and costly, it
was easier and more expedient (marketable) to keep them as simple as
possible.  Thus, brake switch and rotation switches.

> The next question is why do they provide two switches for CW and CCW
> rotation? Not that I would ever do this, but looking at the
> schematic I see
> that if I were to depress both rotation switches at the same
> time, the motor
> would be totally stalled. Seems to me the smart thing to do would
> be to have
> a toggle switch to set the direction, then another switch to
> actually start
> the rotation.
>

You are suggesting moving from a single movement operation to a two-move
operation:
	Press the brake and appropriate direction button/lever, to
	Flip a switch to set direction, then press the brake and motor buttons.

> So you can see where this is leading. I can design my own replacement
> rotator controller box, but as I said, I'm sure many hams have
> already done
> this before, and probably thought of a lot of other ideas I
> haven't thought
> of yet. Thanks for any suggestions and/or pointers for more info on this.
>
I have built two single knob rotator controllers which connected to the
original control box designs.  One was in an mid-1980's 73 Magazine article
entitled Elegant Rotating.

The other was from an article in Feb 96 QST entitled Rotator Pal.

Elegant Rotating was an external add-on with internal connections/mods;
Rotator Pal is strictly internal to the original control box cabinet.

Both work on the single-knob philosophy: Move the knob (pot) to the
direction you want the beam to point.  The circuit releases the brake,
starts the appropriate motor, stops the motor, then, after a set couple of
seconds, sets the brake.

Very cool, indeed.

73,
dale, kg5u