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<font size=3>At 12:42 PM 11/15/07, Paul wrote:<br><br>
</font><blockquote type=cite class=cite cite=""><font size=2>Hi
List,</font><font size=3> <br><br>
</font><font size=2>I have a couple of those cheap max-min
thermo-hygro readers from Pianotek. I'm not sure if they're very
accurate. </font></blockquote><br>
They're more accurate than the Radio Shack ones, but I don't think by
much.<br><br>
<blockquote type=cite class=cite cite=""><font size=2>If you all
remember, last fall/winter I sent in some photos of one of our recital
rooms that Richard West took before I got here with the fog and water
dripping all over everything. It hasn't been that bad since I've
been here, but the last couple of times I've gone in there this past
week, it feels really muggy, but the hygrometer only registers 40-45%
(which would be ideal). Any suggestions on who makes a real
accurate reader?</font><font size=3> </font></blockquote><br>
We have the opposite problem here where Rh can be down into the single
digits in mid-winter. None of the "standard" humidity gauges go
down that far. I use a Cooper Digital Psychrometer much like the one down
the page at
<a href="http://www.techinstrument.com/acatalog/Hygrometers__RH___humidity_.html" eudora="autourl">
http://www.techinstrument.com/acatalog/Hygrometers__RH___humidity_.html</a>
(SAMJR995). It's a digital version of a "sling
psychrometer", the wet/dry bulb unit we use to make truly accurate
RH readings. While it's supposedly accurate +-5% it still reads down to
zero Rh which in worst case might actually be 5%. I've read as low as 3%
in mid-winter here in some churches. In those pianos with DC's installed,
sticking it under the rim for a minute and pressing the "hold"
button shows it's in the 40-43% range at the soundboard even with
extremely low humidities outside the instrument.<br><br>
I also have a USB recording hygrometer that will track the RH and temp
over a long period of time. It's at
<a href="http://www.measurementcomputing.com/cbicatalog/USB-502.asp?dept_id=414&pf_id=1759" eudora="autourl">
http://www.measurementcomputing.com/cbicatalog/USB-502.asp?dept_id=414&pf_id=1759</a>
. It reads very much like the "standard" units and differs
from the Psychrometer's readings. I trust the Cooper more for truly
accurate readings.<br><br>
<x-tab> </x-tab><x-tab>
</x-tab>John<br><br>
<x-sigsep><p></x-sigsep>
<div align="center"><font size=3>-------------------------------<br>
John Musselwhite, RPT - Registered Piano Technician<br>
Musselwhite Piano Services - Calgary, Alberta Canada<br>
Office/cel (403) 246-7717 Fax (403) 255-5268<br>
Outside of Calgary call Toll Free: 1-866-95-PIANO
(1-866-957-4266)<br>
"Three Generations of Experience"<br>
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