On 08/04/2014 09:52, Gareth Magennis wrote:
"N_Cook" wrote in message
...
If something quacks like a duck ...
Alpha M footswitches, have a definite click action by finger feel and by
sound, but only a momentary action. Is there a flavour of momentary switch
that has a click effect for psychological feed back to the operator? SPDT,
2 have 2J4 and one 2J3 white stencilled on the switch body.
3 such in a piece of kit only 3 to 6 months old, but now only momentary.
I'll break into one to check, but anyone come across momentary switches
with click action?


Marshall use them in some footswitch units. It is a soft click, unlike the
latching ones, but a definite click.

There are no manufacturers marks on these switches so I have no idea who
makes them.



Gareth.



I'll look out for those, noticeably different feel to finger actuation
compared to definite mechanical toggle switch action?

Getting inside the problem one, it has all the innards of a conventional
rocker switch put a pin plunger in the stem of the switch instead. No
across-the-stem pin that is part of the mechanism and often bends as the
failure mode on a lot of those latching ones.

Looks like a design flaw and so generic fault with ALPHA M footswitches
of 2012/2013 vintage. Assuming they are supposed to be latching and
don't use all the rocking action as a psychological click generator. The
contact holding rocker pivots over to make the opposite contact but then
swings back. The stem of the sw bottoms out too early, because perhaps,
the pin that is axial to the sprung actuator stem and engages in the
rocker , and bends a bit to follow the 2 rocker positions, is too sharp
and must dig into the PPE plastic of the rocker assembly over a few
hundred actuations. I suspect they've done away with a tiny metal cup
seated in the rocker recess, to receive this pin.