N Cook wrote:

That is going across continents.
To transfer the pulse coding of a remote control at one site to another
learnable type remote control maybe the other side of the world.
Can anyone think of a method that uses off the shelf equipment used in a
domestic environment , ie not using oscilloscopes etc.
Somehow slowing the pulse stream down enough to capture on cam-corder/pc
etc.
Would the average r/c with say a 400 KHz ceramic resonator still function
with the 400KHz one replaced with 100KHz one say.?

--
Diverse Devices, Southampton, England
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An old PC (even a 386) running only a DOS application with all the
interrupts turned off can sample the printer port to memory at maybe 1MHz
and could probably do your task if you attach a photodiode and comparator
of some sort, with a reasonable frequency response, or cheat and open the
remote to get the logic signal out directly. Given sufficient
determination, this might also be achievable with a modern computer running
some sort of windows too, at least in theory. Since the modulation is only
about 40kHz on most remotes, you might be able to find some sound card with
Audiophool grade sample rates like 192kHz, which might also work, with a
suitable photodiode or connection to the LED. As you suggest, slowing down
the clock of the remote would make things easier, and I think it would
work. You could then use a tape recorder, sound card or whatever
non-compressed audio recording device you want. If you slow it down too
much then you might want to put some current limiting in the LED as they
run them above the continuous current rating, and at a sufficiently low
clock rate the LED may burn out.

I think it might be hard to use a VCR and photodiode to record the signal
because having sync pulses might prevent you from capturing enough
continuous signal from the remote. If you can get a VCR to record without
h-sync pulses being present then it would certainly be a very high
bandwidth recording device.

All of the above sounds like more work than putting the learning remote in a
box and posting it to the required location. Why are you interested in
this problem?

Chris