Had a lengthy discussion with one of the reps at Labcor
http://www.labcor.com/index.asp here in Canada (Cole-Parmer in the
U.S.).

He "educated" me to understand that a low priced unit like
http://www.labcor.com/catalog/produc...&sel=356240 2
has a much wider margin for error than the +/- 0.2 published. Namely
it's true accuracy is +/- 0.5 to 0.7. Hence a reading of 3.5 could
literally range from 2.8 to 4.2. He said this is true for any
pen-style meter regardless of make.

Even a more expensive unit like this one
http://www.labcor.com/catalog/produc...&sel=356130 1
with an published accuracy of +/- 0.01 pH has a true margin of error
of +/- 0.5. Just as useless as the first one.

I was "sold" (almost) this unit
http://www.labcor.com/catalog/produc...&sel=356142 0
which apparently has a true margin of error of +/- 0.05. It's price
is $360 Can. and replacement probes are $100 Can.

Have I been "sold" (almost)?

I think I remember reading some threads in this NG where winemakers
were experiencing frustration with adjusting acidity. I.E. the taste
outcomes from acidity adjustments where worse than the original
unadjusted wine. Speculation: could this be because inexpensive (and
grossly untrustworthy) meters are misleading us?

Or ...

Am I remember wrong to begin with?

And ...

Can a fairly inexpensive meter with a "published" accuracy of +/- 0.05
for example be trusted? It never occurred to me that a listed
accuracy range may be suffering from a huge dose of optimism and
literary licence.

Now I'm really confused!

Funny taste in my mouth, in Calgary,

Jim