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[OT] analog footswitch cable's maximum length?

March 27, 2007 | 6:48 am

Hello,

Could anyone tell me what is the maximum reliable length for a basic
footswitch cable?

Roald Baudoux


March 27, 2007 | 6:46 pm

Quote: Roald Baudoux wrote on Mon, 26 March 2007 23:48
—————————————————-
> Hello,
>
> Could anyone tell me what is the maximum reliable length for a basic
> footswitch cable?
>
> Roald Baudoux
>
—————————————————-

Longer than you need. (Depending on the gauge of the wire you use, and the amps output by the thing you’re plugging into.)

More technically, you could look at a "Voltage Drop Calculator"** to see how much resistance the wire in your circuit has. Remember that the signal goes out and comes back. The effect is fairly small, a kilometer of 16 gauge wire has a resistance of about 13.4 ohms. If you have super-long cable, you could send a higher voltage/amperage signal through it. Since most of these controllers are looking for 5v (some 3.3v), you could certainly get a long run using a 9v battery. I would check to voltage with a multimeter before I plugged into an expensive device, though.

See:
** http://www.stealth316.com/2-wire-resistance.htm

Sorry for the too much information.

mz


March 28, 2007 | 9:39 am

Roald Baudoux schrieb:
> Could anyone tell me what is the maximum reliable length for a basic
> footswitch cable?

It should be fine to send it around the world… ;-)

But you might ask because of problems you encountered?
I once made a cable for a footswitch to plug into a controller input. My
theory was it would only output 127 or 0 as value. But inbetween the two
positions, there was a problem. Kind of undefined state, where it
dependes a lot how the input circuit is designed. But this is (almost)
independent of the length of the cable…

My solution was, beside a split object, to prevent double triggers
within Max…

Stefan


Stefan Tiedje————x——-
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March 28, 2007 | 12:48 pm

On 28 mars 07, at 11:39, Stefan Tiedje wrote:

> Roald Baudoux schrieb:
>> Could anyone tell me what is the maximum reliable length for a basic
>> footswitch cable?
>
> It should be fine to send it around the world… ;-)

< ...>

> My solution was, beside a split object, to prevent double triggers
> within Max…

With switches, preventing double triggger is something that should
always be done.

The length of the cable of a footswitch shouldn’t be a problem if the
switch is plugged into a sustain input.

But if you plug it on a CV input (thru some basic wiring), then the
length may be a problem: with 25m, the MIDI controller value I had was
125 rather than 127. In that case, instead of checking [sel 127], you
should rather use something like [> 120] (depending on the polarity of
the pedal).

_____________________________
Patrick Delges

Centre de Recherches et de Formation Musicales de Wallonie asbl

http://users.skynet.be/crfmw/max


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