I'm so stupid... Was: Head Cleaners

From: Tony Duell <ard_at_p850ug1.demon.co.uk>
Date: Tue Jul 6 15:21:46 2004

> My RadioShack multimeter (computerized mongothingy with RS-232 &
> everything) decided it didn't want to measure voltage anymore. It did
> everything else fine[1] so I decided I was gonna have a hand at tearing the
> thing apart to see what the heck is going on. (It's probably one of three
> things I own that I've not yet taken apart yet.) So I took it *all* the way

Odd... I dismantled my Fluke 85 before I bought it (I got it second-hand,
with some display segments dim, and I wanted to check if the problem was
just bad contacts at the zebra-strip. It was ;-))

And I pulled the case on my Logicdart the day I got it (anyone else think
the PCB in this instrument should be called a 'dartboard'???)

>
> So, then I think: Waitaminit, dumbass! That outlet that the wallwart is
> plugged into is a bit flakey, maybe there's no voltage to measure! So I

A friend of mine bought a Fluke because the swtich on his old cheapo-meter
had gone flakey. It told him that a socket outlet he was working on was
dead when in fact it was still live (UK mains, 240V). After picking
himself up from the other side of the room, he bought a Fluke...

> grab a standard alkaline cell, and yea, I get 1.5 volts. So I test a *known
> working* 12v wallwart - still nothing. Odd... then I say to myself...
>
> Self: When's the last time you changed the battery in this darned thing???
>
> I replaced the 9v battery, and everything worked fine![2]
>
> Did I feel stupid? Yea... but I got over it quickly, as I was happy it was
> working again -- and now I know what the innards of the thing look like, in
> case the next time the problems not so simple...
>
> Laterz,
> Roger "Merch" Merchberger
>
> [1] including measuring resistance, which is usually the first thing to go
> on a low battery condition...
>
> [2] And Tony says you can never fix anything right by just partswapping... ;^>

Batteries may well be an exception to that, but actually, I always test
them _on load_ when I have problemes. And before you ask 'how do you
check the battery that powers the votlmeter', I have to admit to owning
many, many, voltmeters...

-tony
Received on Tue Jul 06 2004 - 15:21:46 BST