Can I use a present servo in old system radio
 

Dear Guru s: I have an 1977 model OS Cougar 5 ch.Radio set ,4 normal Ch.and 1 for retract 27Mhz.AM.
It has 4 line servos and was usable until last week one of the 4 servo s got weird during rest in my trainer at home.I noticed by chance.
My question is: Can I use any contemprary 3 line servos in any way to make my set still usable?If so , how?

RE: Can I use a present servo in old system radio
 

The forth wire in a four wire servo was for the center tap of the battery required in the old servos. It is not required for current servos. New servos should work if the pulse is of the right polarity. Some of the older systems pulse polarity opposite of current standard.
Make sure the +, - match, and the signal wire match on the connector and try it. Ignore the forth wire. You can't hurt it if the + and - wires are correct

RE: Can I use a present servo in old system radio
 

DirtYbird,Thank you for your kind answer.This will be great if it work.

RE: Can I use a present servo in old system radio
 

And I just could checked it and worked.Thank you again Dirtybird.My appreciation.