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<DIV><FONT face=Arial size=2>How about the "Professional" meter that Pianotek
sells?</FONT></DIV>
<DIV><FONT face=Arial size=2>I like it because it reads quickly and reads lower
RH than the Radio Shack types.</FONT></DIV>
<DIV><FONT face=Arial size=2>I haven't compared it to a sling psychrometer. The
sling psychrometers I have found were rather expensive.</FONT></DIV>
<DIV><FONT face=Arial size=2>Ed Sutton</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<BLOCKQUOTE dir=ltr
style="PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #000000 2px solid; MARGIN-RIGHT: 0px">
<DIV style="FONT: 10pt arial">----- Original Message ----- </DIV>
<DIV
style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: black"><B>From:</B>
<A title=john@musselwhite.com href="mailto:john@musselwhite.com">John
Musselwhite</A> </DIV>
<DIV style="FONT: 10pt arial"><B>To:</B> <A title=caut@ptg.org
href="mailto:caut@ptg.org">College and University Technicians</A> </DIV>
<DIV style="FONT: 10pt arial"><B>Sent:</B> Thursday, November 15, 2007 4:41
PM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> Re: [CAUT] Hygrometers</DIV>
<DIV><BR></DIV><FONT size=3>At 12:42 PM 11/15/07, Paul wrote:<BR><BR></FONT>
<BLOCKQUOTE class=cite cite="" type="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 class=cite cite="" type="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></FONT></DIV></BLOCKQUOTE></BODY></HTML>