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Dave Platt Dave Platt is offline
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Default OT--Actual elecytronics repair question

In article ,
Gareth Magennis wrote:

Yaesu VX-5R tri-band hand held. Momentary contact power on/off button.

I've owned this radio for 9 or 10 years. Recently I have to push several
times on this rubber on/off button to get the radio to come on. But it
always takes just one touch to turn it off. And the radio works fine
otherwise including all the other buttons. Just have to play around
pressing the button maybe three/four/five times. Sometimes it powers on
when pressed once! But always shuts off with just one easy push.
This indicates to me that it's not a problem with button contact but
rather a microprocessor problem.


Could be a microprocessor controlled delay programme whereby you have to
hold the on button on for longer to turn it on, than the off button to turn
it off. Perhaps because it is more important to screen out accidental ons
than accidental offs.

And/Or, If the button is dirty, and thus resets its state randomly/rapidly
during a single press, perhaps this results in favour of the Off debounce
and/or delay routines rather than the "On" routines.


Quite reasonable suggestions.

The usual "field engineering" fix would be to simply replace the
elastomeric key membrane (Yaesu used to make this available as a
standard service item for the VX-5; dunno if it's still available) or
use the CAIG contact-repair kit to re-goop the back of the POWER
button and see if increasing its conductivity fixes the problem.

--
Dave Platt AE6EO
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