Slowing down Responder rotators

LineSpotter

Member
Nov 6, 2013
195
AmericanSouthwest
I managed to dig up a new Responder DX this week
Still in the box with red lense and a spare blue one :cool:
The only down side is it has the fast rotators.....(barf)

Does anyone know if the high speed was obtained with gearing or motor speed?
Does anyone know how to reduce the speed to 'normal'?

I have an old standard speed DX that doesn't not have these resistors, but it also has different motors and gears, so I'm not sure what's up exactly.

218468

218469
 
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cmb56

Member
May 22, 2010
746
Norrköping, Sweden
You will probably have better answers from others that have more knowledge of electronics than I, like @MtnMan .

I think the ”resistors” are capacitors for noice suppression.

Depending of the rotators rpm you probably need to reduce the motors rpm to half its rpm.
That means you need a resistor that take down the Voltage from 12V to 6V.

Michael
 

Sparky_911

Supporting Donor
May 15, 2013
2,648
Central Illinois
Count the teeth on the drive gear of the new one and the old one. Then see if the worm gears are the same diameter. If old v new are the same size/tooth count/diameter etc., then the motor is the reason. Could be that motors were swapped out on one of the bars?
 

MtnMan

Member
Dec 20, 2012
1,533
Eastern PA
@cmb56 is correct. Those are capacitors for electrical noise suppression.

Mechanical speed reduction, i.e. a gear swap, would be the elegant solution. You could experiment with adding resistors in series with the motor. That will reduce the speed, but also the torque, so the motor might be more sluggish.
 

LineSpotter

Member
Nov 6, 2013
195
AmericanSouthwest
Found a solution in case anyone else is interested....

I spoke to the avionics guy who built my new panel, and he suggested a 'Pulse Wave Modulator' or PWM. They are widely available and can be had for like 5 bucks, just snip the motor leads and wire into the PWM. Then set whatever speed you want with no load issues or heat.

Once I get around to ordering and wire one up I'll update with results.




218556
 
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Skulldigger

Member
Aug 23, 2015
1,739
Georgia / USA
Interesting. It does not drop voltage it shuts the power on and off multiple times a minutes to decrease speed. Very effective for motors as the inertia maintains consistency and is not jerky. Seems ideal. Very cool discovery.
 

Skulldigger

Member
Aug 23, 2015
1,739
Georgia / USA
Was thinking, some lights are wired inline. My have to split the bulb from the motor wiring or the bulb will flash.
 
May 21, 2010
1,258
Minnesota
A PWM works great to control the rotators, was just going to recommend it. I used one in an MX7000 and made a pair of rotators dual speed.

When playing around with mine (looks like the one you pictured) I noticed it controls via the ground. I had to isolate the motor from common ground. I did not need to cut or change the positive wiring. It looks like this should not be an issue with your setup. Just don't run the lightbulb through the PWM too as that one is only rated at 2 amps.

 
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