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    Extension foot switch mono or stereo

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    NZ_Nick

    Posts : 16
    Join date : 2015-10-15

    Extension foot switch mono or stereo

    Post by NZ_Nick on Wed Feb 24, 2016 2:10 pm

    Hi guys
    I want to put together a couple of single switches to plug into the controller functions of the FSM Mkiii-e.g. to control boost and FX on/off.
    Do these need to be mono or stereo connections?

    Thanks in advance.
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    bordonbert

    Posts : 767
    Join date : 2015-01-28
    Age : 97
    Location : Southern England

    Re: Extension foot switch mono or stereo

    Post by bordonbert on Sat Mar 05, 2016 10:31 am

    Sorry Nick.  Somehow I missed this post completely and can't figure out why.  I know it's a while since you posted it but here is the info as I see it.  Sorry if you are very technical and I seem to talk down to you, that's only for the benefit of others who may not be experienced at all.

    It isn't absolutely necessary electrically to have a screened cable like a guitar lead for these switches but it is what normally gets used with jack plugs.  The switch can be either wired mono or stereo but it will need to be set up correctly, (which is very simple):


    1.  If you are making your own with a mono plug it's a doddle.  Use single core cable, (one core + screen braid), and wire to the diagram and description below.

    2.  If you are making up your own and choose to use a stereo plug there are again two approaches:

      1.   You could use a single core screened cable.  Connect the core to the tip and the screen to the sleeve, then add a tiny link between the sleeve and ring inside the plug.  That link makes the stereo plug simulate a mono one.  So we have:  core -> tip, screen -> sleeve + ring.

      2.  You could use a dual core screened cable.  That usually has two separate red and white wires inside a braid screen though other colours do turn up.  You connect the red to the tip of the plug, the white to the ring and the braid to the screen.  Inside your switch for the FSM432 just make sure to then connect the braid and white together to do the same job as the link in the last case.  So that come down to:  red -> tip, white -> ring, screen -> sleeve, connect white and screen inside switch.



    Now wiring the switch.  The manual clearly shows this as a mono plug from the switch and you just wire the switch across the tip and sleeve.  That takes care of everything.  Our stereo jack plug is fine as long as the ring and sleeve are connected together as described in the cases above.  If you want to add a LED to show the operation state then just put it between the tip and sleeve in series with the switch with it's anode towards the tip and cathode towards the sleeve.  If you're not technical the anode is the +ve which has the longer lead and the cathode is the -ve with the shorter lead and sometimes a flat spot on the rim of the lens.  It isn't necessary to have the LED for the switch to work, you can just leave it out without any problems, but it's a nice touch.

    Here is H&Ks schematic for it from the manual.

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    So in a simpler way:  jack tip -> solder to LED long leg (anode), LED short leg (cathode) -> solder to switch centre, switch edge -> solder to jack sleeve (+ jack ring if stereo plug is used).

    Hope it helps even at this late date. Let us know if it isn't clear.

      Current date/time is Tue Sep 26, 2017 1:15 pm