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Electronics => Electronics => Topic started by: Gertlex on August 08, 2007, 02:40:38 PM

Title: Using an old six wire servo?
Post by: Gertlex on August 08, 2007, 02:40:38 PM
I've got this old old servo that came with the car that I converted to bluetooth.  It's totally free of any manufacturer's name, just the blue CE sticker (electronics/electrics standards compliance or something)

Is it possible to use such a servo with a servo controller (Mini SSC II) that uses three wire servos?

Orange and black: the motor terminals
Blue soldered to the entwined terminals of the capacitors that also link the two motor terminals
Green, White, Yellow: three terminals of the potentiometer, I think.  White is the center terminal wire... three wires means its being used to monitor the voltage, I think.  Yes, I severed all six wires from the original circuit board.

Quoting a website of a guy that has refurbished a few of these NIKKO Alienators:
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The included servo was in an odd L shape and had 6 wires for what seemed to be a manual position sensor. Really low tech.

Does this pretty much mean the servo is useless until, perhaps, when i start dealing with real control boards?

I can post pictures if needed.
Title: Re: Using an old six wire servo?
Post by: Soeren on August 08, 2007, 05:10:50 PM
Hi,

Orange and black: the motor terminals
Blue soldered to the entwined terminals of the capacitors that also link the two motor terminals
Green, White, Yellow: three terminals of the potentiometer, I think.  White is the center terminal wire... three wires means its being used to monitor the voltage, I think.
What you have is just two parts of a servo, the motor and the (position) feedback potentiometer. You miss the electronics tying it together.
The blue lead should go to Protective ground/the metal frame of a vehicle.
The potentiometer will go between ground (or a low ref. voltage) and +V (or a higher ref. voltage than the other end). The wiper (the center terminal) will thus give a voltage which is proportional to servo position.

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Does this pretty much mean the servo is useless until, perhaps, when i start dealing with real control boards?
Nope, it could be used with an op-amp to give positioning based on an input voltage.

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I can post pictures if needed.
Make them of Claudia Schiffer then ;)
Title: Re: Using an old six wire servo?
Post by: Admin on August 11, 2007, 09:24:54 AM
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Does this pretty much mean the servo is useless until, perhaps, when i start dealing with real control boards?
Nope, it could be used with an op-amp to give positioning based on an input voltage.
You can also send the voltage from the pot into the ADC of your microcontroller. Then you can program your own servo into some form of feedback system.

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I can post pictures if needed.
I can pretty much picture in my head what it looks like, but Im curious to see how the pot is hooked up to the motor . . .

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Make them of Claudia Schiffer then
or Roseanne!

...

(just kidding)