On 30.7.2012 17:52, Dwayne Reid wrote:
> Good day to all.
>
> Many years ago, I built some announcer control boxes intended for use
> with Broadcasters.  These are fairly simple: mic preamp, two separate
> listen inputs (each with its own level control) and intercom talkback
> / IFB (separate talk button and listen level control.  They've been
> working well for more than 20 years now.
>
> However, they suffer from my poor choice of switches.  There are two
> push-button switches (Honeywell / Micro "AML" line) for cough and
> talk-back and a toggle switch for turning the mic on or off.  All of
> these are acoustically noisy.
>
> I can live with the noise of the push-button switches but the noise
> from the toggle switch is annoying to the audio guys who mix the show
> audio.  They've asked me to do something about it.

How about a hall effect button/switch?

Something like this:
http://www.ottoexcellence.com/shop-by-department/controls/hall-effect/

Djula


>
> The toggle switch is a standard mini-toggle switch that mounts in a
> 1/4" diameter hole.  There is a fair amount of space around that
> switch but the depth is limited.  Otherwise, I'd just install an
> old-time telephone lever switch and call it done.
>
> Can anyone suggest a mini-toggle or similar switch that is not noisy
> when you slam its lever from one end-stop to the other?
>
> One option I have been considering is to replace the toggle switch
> with a keyboard switch module.  These are highly reliable pushbutton
> switches that were designed for use in computer keyboards before the
> current keyboard designs came along.  I would then just add an
> electronic alternate-action circuit with indicator LED to show that
> the mic was live.
>
> I've used these keyboard switches as pushbuttons for similar purposes
> in years gone by but I simply don't have enough of them around and
> I'm pretty sure that they have been obsolete for a couple of decades.
>
> Any suggestions gratefully accepted.
>
> Many thanks!
>
> dwayne
>
--=20
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