I probably have one for an old ACE servo. ACE provided complete
schematics/theory of operation of all their radio equipment(since many were kits)
and you could order every part/component.They used the Signetics NE544 as most
all servos of the 70's-80's did. According to  https://www.fmadirect.com/home.htm
all of todays servos use the same Mitsubishi chip but I don't know if it emulates the
old Signetics chip.
 I also have a book with circuits from 60's-70's
>
> Related to the other thread, about driving servos, does
> anyone happen to have an actual schematic for the internal
> electronics for a 3-pin, RC-model type servo?
>
> thanks,
> - dan michaels
> www.oricomtech.com

--
http://www.piclist.com hint: The list server can filter out subtopics
(like ads or off topics) for you. See http://www.piclist.com/#topics