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Servo Stop and Reverse

bigkim100

Apr 17, 2013
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There are many different circuit diagrams to run a servo in forward and reverse on the internet.
Most deal with using a 555 to generate pulses.
I would like to add a way to stop and reverse the servo at a user-defined speed (via Potentiometer), at the end of its path at both ends of the servo run.
I do not have current voltage requirements, other than the voltage used to run the 555, but the Hobby servos I wish to use, usually run the happiest at 6 to 9vdc.
I have included a diagram for the circuit that runs the servo, often called a "servo exerciser" by RC Hobbyists.
Thank you for any help, in advance
Kim
 

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Bluejets

Oct 5, 2014
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Servos will not withstand anything above 6v normally.
There are some that do but most will not.
There is an ebay servo tester that runs servos either manually via a pot or automatically through their range back and forth for a couple of dollars.
 

bigkim100

Apr 17, 2013
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Servos will not withstand anything above 6v normally.
There are some that do but most will not.
There is an ebay servo tester that runs servos either manually via a pot or automatically through their range back and forth for a couple of dollars.
Their problem is with those is that I wish to enclose these into something, and when those units that you mentioned power up, they power up in a mode different than the mode then the one that I want them to be in.
 

Harald Kapp

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Nov 17, 2011
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Does it have to be a servo? Have a look at this post. Using a DC motor an a dpdt switch is all you may need. Speed can be adjusted by setting the supply voltage to the motor or using gears.
 

Harald Kapp

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thats EXACTLY what I need
Often the problem is not the problem that is being described, it is the way the question/description is put. Describe what you want to achieve to get help finding a good solution. Had you asked about a way to have movement go back and forth instead of asking how to control a servo, the answers, I'm sure, would have looked differently from the start.

Don't ask how to do this using this or that.
But rest assured, you're not alone here. I experience this daily - here and at my workplace.
 

John Canon

Jun 1, 2022
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Does it have to be a servo? Have a look at this post. Using a DC motor an a dpdt switch is all you may need. Speed can be adjusted by setting the supply voltage to the motor or using gears.
Good old analog! We went to the moon on analog, and the humans did the digital "turn it on.....now" "roger"
 

bigkim100

Apr 17, 2013
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Good old analog! We went to the moon on analog, and the humans did the digital "turn it on.....now" "roger"
I must save bravo in your answer, as I am getting tired of having EVERY project steered to a microcontroller
 

Bluejets

Oct 5, 2014
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what a waste of time and money, servo exercisers are available for a buck or two

Well, it was you who poo pooed the same suggestion first up in #3 so don't shoot the messenger.

In fact if you bothered to look you'd see the suggested replacement fitted your "mode first turned on" requirement.

I'd say best you make up your mind about what you really want.
 

bigkim100

Apr 17, 2013
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Well, it was you who poo pooed the same suggestion first up in #3 so don't shoot the messenger.

In fact if you bothered to look you'd see the suggested replacement fitted your "mode first turned on" requirement.

I'd say best you make up your mind about what you really want.

Man, someone woke up on the wrong side of the bed.
like most projects on here, as people start to respond with different ways to do things, the specific requirements are massaged, and changed. What seemed to be the only way in my head, a servo, with controller, slowly became a slow geared motor, with limit switches at the end of travel to stop and reverse the motor. I still maintain that dedication of an entire microcontroller board to build something that I can order from EBay or Ali Express for 99 cents is wasteful of both time, energy, and product, but as per usual, this was expressed only as my personal opinion.
As you have expressed your feelings toward my statement so eloquently, and forcefully, I shall return that favour by stating to you... loosen up, and cool down.
 
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