> From:    Doug Simmons <[log in to unmask]>
>
> Since this is an older machine I'm sure that it doesn't have a USB bus, the
> only other alternative (I know of) for a keyboard.  I have had problems
> with some motherboards where the keyboard connector has parted from the
> motherboard. It sticks out from the MB and with the tugging and pulls, it
> is very vulnerable for this type damage. A solder job _may_ be able to fix
> the keyboard connector back to the motherboard and fix the problem. I have
> had mixed success in doing these repairs.

> Doug

Also, look for a "pico" fuse - looks like a 1/4 W resistor without the color
bands.  Usually you can see a rating such as "2 A" printed on it.  Use a
low-voltage ohmmeter or "beeper" to check continuity.  Something like a
loose screw in the keyboard, or even fumbling the keyboard connection
with the power on, could blow the fuse.

Another, hard-to-spot failure is an open solder joint, caused by metal
fatigue leading to a microscopic crack around the leg of the connector.  In
this case, you will have continuity from the keyboard to the end of the
leg - but not to the surrounding trace.  Often, just touching the
connector, or the end of the leg affected will make an intermittent contact.

If you are not confident that you can do solder repairs on the motherboard
without causing further damage, get someone you do trust to do it.  On the
other hand, if the board is old, and you don't care if it ever works again,
you could practice your soldering technique, and regard it as a "learning
experience".


> At 4/10/00 09:02 AM +1200, Nicki Gemmell wrote:
>
> >Hi
> >I have got a Digital Venturis 575 which reports a Keyboard failure at boot
> >up....

Boyd Ramsay

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