16 June 2016

Multi Multimeters

The other day I got myself into a pickle.
A project needed a solid multimeter
that could measure ohms/resistance,
and I realized mine were all glitchy.
So now you're gonna hear all about them...
Yes a fun yawner!
My go to tester for the past 8 years is this
beater Blue-Point MT145.
It's never worked perfectly,
sometimes doesn't even want to turn on.
The culprit is obvious,
severely corroded battery contacts.
That blue stuff grows overnight,
every time I gotta twist the batteries or scrape it.
The big problem is it's basically a voltmeter,
doesn't read resistance for chit.
Sometimes it'll work,
sometimes there's this ear piercing beep.
It just sucks.
I'm not a Snap-On guy anyway,
and I like the analog needle swing.
My previous machine was this old tank.
A Knight Auto Analyzer,
nice and heavy so it doesn't slide around.
I loved it for shop use,
other than the knob being broken.
That little thing sucks to twist,
and I never turned it off.
Doh...
This thing uses 4 D batteries.
Who uses D batteries any more?
Have you priced good D batteries lately?
They lasted for years, 
maybe a decade.
Even at $1.50/yr it's not a bad deal,
but I'll wait for a cheap swap meet deal...
The problem is this only reads high ohms,
so it's limited for basic use,
although there are many engine features.
This hefty unit was a garage sale score,
a 1980's boxed Simpson 260 series 7.
The 260 model has been made since the 1930's!
Many believe it's the best US analog meter made.
The inventor built the compass for Lindbergh's Spirit of St. Louis!
I've had this for a couple years now,
and admit to never using it.
One reason is it's in such good condition,
I'd probably drop it.
That was just an excuse,
the real reason is these friggin batteries.
A big D and an old school 9-volt,
yeah the one you used to lick as a kid.
Dang these are expensive now!
Mainly because they come in 2-packs.
I bit the bullet and this works so smooth.
eBay helped with the broken leather case.
I'll need to zip tie it or something,
but that's the armor it deserves.
This story has evolved over many years,
nothing was a surprise,
there was a new object to hunt for.
Sure there are dozens of new cheesy $20 units
but where's the fun in that.
Before buying those batteries,
I found this $7 TMK TW-20S,
that looked like an old solid meter.
Nope.
TMK makes a version similar to the 260,
but there's no info on this TW model.
Time to crack it open.
This seemed to have heavy duty guts.
Aha!
What's this burn mark...
A 10k ohm resistor?
This is the project that inspired this installment.
WTF is going on here at the dinner table!?
See how multimeters are helping other multimeters?
The $2 resistor was swapped and it works like a charm.
But wait there's more!
While the resistor was being shipped from China,
I found this Radio Shack unit.
I'd asked earlier and he wanted $4,
then price checked eBay.
A Micronta 22-202u goes for $20-30!
Someone had spilled coffee on it 
before I returned.
$1.87 was the change I had in my pocket.
Score!
I made some red:black leads and it worked great!
Fits into the toolbox no problem.
Now there are enough multimeters for the house,
shop, a mobile one, and a loaner!
Holey Chit...
TP

2 comments:

  1. Travis! Good to see you're still at it!Hope all is well.
    --Hans with the fity.

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    Replies
    1. Hey Hans!!
      He you are doing well too!
      Are you still doing the euro-Texas thing?
      TP

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