StellarTech wrote:
"Hamad bin Turki al Salami" wrote in message
. ..
I have a bunch of aging instruments I need to tune up. One common
problem with these things is the buttons become flaky over time.
(I'm not sure what the name for this kind of button is, but what
I'm talking about is a "stateless" push button, which functions
like a computer keyboard key. It is typically used to increment
a number or move a cursor or something. You push it and it moves
the cursor one space. You push it again to get another space.
Often, if you hold it down, a repeat kicks in after a delay of
a half second or so.)

Over time, the contacts inside the button become dirty or oxidized
or whatever and the button becomes flaky. You have to push hard
to get a response, or you get multiple responses from one push,
etc.

If I can get the button open, I can usually improve it by cleaning
it with alcohol, but sometimes even that doesn't completely fix
the problem.

Does anyone here have tips for this kind of thing?

I'd especially like to know if there are tricks for fixing these
without opening the buttons up. There are a lot of different
kinds of buttons and some are hard to open and some take me
a while to figure out how to open.

I assume you are referring to pcb-mounted momentary contact switches. The
best remedy I have found is WD-40. Use the nozzle tube and apply a small
amount right to the small gap where the actuator protrudes from the housing.
Then rapidly & repeatedly push the actuator about 20-30 times. You may have
to apply the '40 more than once. And of course, clean the PCB afterwards. I
assume it's the foaming action of the WD-40 that allows it to get to the
contacts in the switch. At any rate, it usually does the trick.



Dont do this! Without wishing to start yet another WD40 war, the
damaging effects of WD40 on electronics are well documented. The
manufacturers of WD40 themselves do not advise applying their product to
electronic components.

There are plenty of products designed for the purpose of switch cleaning.

Ron(UK)