Controlling PCM servo with switch
#1
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Controlling PCM servo with switch
Electronics question, regarding rc-servos:
I am aware of how PCM coding works, but if I have an application where I only need the two extreme positions of the servo. Can I just send 0V for one position and 12V for one position? Some manufacturers say no, that I need a frequency too, but I remember having tried this in practise, and found it to work.
If not, can anyone please show me of how to make a simple resistor-capacitor circuit to create the frequency needed to make the rc-servo work?
I also want to know if I can connect two 6V servos in line with eachother, to a 12V power source. The servos are going to be operated simultaneously.
I would also appreciate recommendations of servo manufacturers. I need a servo which is weather resistant but otherwise reasonably priced. It's for a commercial invention that I'm trying to develop.
If it matters, I'm located in Sweden.
Best regards,
Erik
I am aware of how PCM coding works, but if I have an application where I only need the two extreme positions of the servo. Can I just send 0V for one position and 12V for one position? Some manufacturers say no, that I need a frequency too, but I remember having tried this in practise, and found it to work.
If not, can anyone please show me of how to make a simple resistor-capacitor circuit to create the frequency needed to make the rc-servo work?
I also want to know if I can connect two 6V servos in line with eachother, to a 12V power source. The servos are going to be operated simultaneously.
I would also appreciate recommendations of servo manufacturers. I need a servo which is weather resistant but otherwise reasonably priced. It's for a commercial invention that I'm trying to develop.
If it matters, I'm located in Sweden.
Best regards,
Erik
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RE: Controlling PCM servo with switch
Erik,
If you haven't already been there, you may want to try to post your questions on www.rc-unionen.dk I can think of a few people on that site who I think can give you your answers, and it's local to you as well.
DKjens
If you haven't already been there, you may want to try to post your questions on www.rc-unionen.dk I can think of a few people on that site who I think can give you your answers, and it's local to you as well.
DKjens
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RE: Controlling PCM servo with switch
The servo requires a pulse width of ~1, 1.5, 2ms to function. one end, center, other end.
you can not just apply a voltage to the input.
you can not just apply a voltage to the input.
#4
RE: Controlling PCM servo with switch
What you are looking for is a POD pulse omission detector servo --
Futaba had one a few years ago - very good 180 degree. I think number was " 136 retract servo"
but not 12v - and required the std Futaba rf rate.
when tx was OFF-- the servo saw no pulse -went to one direction - Then when you turned TX ON ,-- if--it saw a short pulse. it held that position - then selecting other switch position -LONG PULSE-- it rotated to other extreme end (180 throw). Ithink the servo pot had two tracks -- find one and see if it helps you.
Futaba had one a few years ago - very good 180 degree. I think number was " 136 retract servo"
but not 12v - and required the std Futaba rf rate.
when tx was OFF-- the servo saw no pulse -went to one direction - Then when you turned TX ON ,-- if--it saw a short pulse. it held that position - then selecting other switch position -LONG PULSE-- it rotated to other extreme end (180 throw). Ithink the servo pot had two tracks -- find one and see if it helps you.
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RE: Controlling PCM servo with switch
here you can find some info about a Servo tester, that can generate the correct signal:
http://www.uoguelph.ca/~antoon/index.htm
http://www.uoguelph.ca/~antoon/index.htm