On Tue, 17 Jul 2012 13:38:45 -0700, "Guv Bob"
wrote:

wrote in message ...
On Jul 16, 6:25 pm, "John F. F." wrote:
Hi all

Does anyone know howto change the code on a very old Sears garage door
opener. It is the super old style where you have to press 2 buttons on the
transmitter to open or close it. Has to be proibably 25 39 years old. The
remote only has one bar you press to activate it. Thanks. Happy summer
John

- The oldest ones I had used to use dip switches
- inside the remote and inside the receiver.

Same here. Mine's c. 1992-94 from Sears. Never had one minute of trouble with opener. Only have had to change batteries in the remote every few years.
http://imageshack.us/f/151/searst.jpg/

If it is *really old*, they didn't use codes. All the remotes were
pretty much on the same RF frequency (really realy old was 27 MHz,
just really old on 300MHz). They modulated the carrier with one of a
dozen or so audio tones to avoid interference with your neighbors.