On Mon, 10 Jul 2006 06:22:10 -0400, "Bill"
wrote:

A couple of months ago I posted about a problem getting my Overhead Door
remote to stay adjusted. It is a single button 360mhz version.
The problem centered around the tuning slug being loose and suggestions here
included adding a piece of rubber band and also threaded wax.
Now the remote works if I adjust the slug each time while holding down the
button. Funny part is it doesn't hold the new adjustment.
Every time I use it I must "re-tune" it and not always in the same
direction. It varies in CW and CCW and degrees of turn.

Now I notice on the pc board an adjustment button marked "Learn". This makes
me think a programming method might apply to keep the tuned slug to one
frequency. What do you think?
Bill

The "Learn" function has nothing to do with the tuning. It refers to
the digital rolling code that is used to keep the receiver and the
transmitter in sync. These rolling codes are used instead of a fixed
code so that an attacker cannot simply record the signal off the air
from your transmitter and then replay it later to make your door open.
The code needs to change every time. The Learn function just tells
the receiver to listen to the next thing it hears off the air and
accept it as the correct rolling code, and then continue in the
sequence of codes from there on.


-Robert Scott
Ypsilanti, Michigan

A couple of months ago I posted about a problem getting my Overhead Door
remote to stay adjusted. It is a single button 360mhz version.
The problem centered around the tuning slug being loose and suggestions here
included adding a piece of rubber band and also threaded wax.
Now the remote works if I adjust the slug each time while holding down the
button. Funny part is it doesn't hold the new adjustment.
Every time I use it I must "re-tune" it and not always in the same
direction. It varies in CW and CCW and degrees of turn.

Now I notice on the pc board an adjustment button marked "Learn". This makes
me think a programming method might apply to keep the tuned slug to one
frequency. What do you think?
Bill

--
Bill W.
http://Wielert.net

"Tony Hwang" wrote in message
news:m6tsg.148520$Mn5.61197@pd7tw3no...
Bill wrote:
A couple of months ago I posted about a problem getting my Overhead Door
remote to stay adjusted. It is a single button 360mhz version.
The problem centered around the tuning slug being loose and suggestions
here included adding a piece of rubber band and also threaded wax.
Now the remote works if I adjust the slug each time while holding down
the button. Funny part is it doesn't hold the new adjustment.
Every time I use it I must "re-tune" it and not always in the same
direction. It varies in CW and CCW and degrees of turn.

Now I notice on the pc board an adjustment button marked "Learn". This
makes me think a programming method might apply to keep the tuned slug to
one frequency. What do you think?
Bill

Hi,
That probably means the frequency is drifting.
Some component is going bad. Know something about PLL?
Good oscillator circuits are incorporated with PLL. Has fresh battery in
the remote to begin with?

Yes a fresh battery is imporant. Also without test equipment and alignment
info it would be impossible to tell whether the transmitter or receiver has
a fault.