<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:st1="urn:schemas-microsoft-com:office:smarttags" xmlns="http://www.w3.org/TR/REC-html40"> <head> <META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=us-ascii"> <meta name=Generator content="Microsoft Word 11 (filtered medium)"> <o:SmartTagType namespaceuri="urn:schemas-microsoft-com:office:smarttags" name="country-region"/> <o:SmartTagType namespaceuri="urn:schemas-microsoft-com:office:smarttags" name="State"/> <o:SmartTagType namespaceuri="urn:schemas-microsoft-com:office:smarttags" name="City"/> <o:SmartTagType namespaceuri="urn:schemas-microsoft-com:office:smarttags" name="place"/>  <style>  </style>  </head> <body bgcolor=white lang=EN-US link=blue vlink=blue> <div class=Section1> Hi Ed, Paul, et al,<o:p></o:p> I recently bought one of the “Professional” hygrometers from Pianotek because I had heard the same comments from several other people.  Well, for the past two months I’ve been using it side by side along with a Dampp-chaser hygrometer a/o ones that my clients happen to be using.  I’d like to say that the small difference in RH that it reads hardly amounts to anything.  AND……it takes quite a while (like five minutes) to settle down and give an accurate reading from what it registered in my case, in my car, traveling from the last appointment.  <o:p></o:p> <o:p> </o:p> At first I would smugly take a reading off of it immediately and was surprised at what a different result it gave from what was in the piano.  I congratulated myself on upgrading my tool and being a true “professional.  However, one time I just let it sit there while I was tuning and noticed how much it changed until it ended up with almost the same as the one in the piano.  I observe this every day now.  And I’m asking myself why I spent all of that extra money.  One client proudly showed me his thermo-hygrometer (with memory) that he bought at Walmart for $6.  It read the same as my fancy-schmancy “professional” one.  <o:p></o:p> <o:p> </o:p> Comments?  ;>)<o:p></o:p> jeannie<o:p></o:p> <o:p> </o:p> <div> <div class=MsoNormal align=center style='text-align:center'> <hr size=2 width="100%" align=center tabindex=-1> </div> From: caut-bounces@ptg.org [mailto:caut-bounces@ptg.org] On Behalf Of Ed Sutton Sent: Thursday, November 15, 2007 3:05 PM To: College and University Technicians Subject: Re: [CAUT] Hygrometers<o:p></o:p> </div> <o:p> </o:p> <div> How about the "Professional" meter that Pianotek sells?<o:p></o:p> </div> <div> I like it because it reads quickly and reads lower RH than the Radio Shack types.<o:p></o:p> </div> <div> I haven't compared it to a sling psychrometer. The sling psychrometers I have found were rather expensive.<o:p></o:p> </div> <div> Ed Sutton<o:p></o:p> </div> <div>  <o:p></o:p> </div> <blockquote style='border:none;border-left:solid black 1.5pt;padding:0in 0in 0in 4.0pt; margin-left:3.75pt;margin-top:5.0pt;margin-right:0in;margin-bottom:5.0pt'> <div> ----- Original Message ----- <o:p></o:p> </div> <div style='font-color:black'> From: <a href="mailto:john@musselwhite.com" title="john@musselwhite.com">John Musselwhite</a> <o:p></o:p> </div> <div> To: <a href="mailto:caut@ptg.org" title="caut@ptg.org">College and University Technicians</a> <o:p></o:p> </div> <div> Sent: Thursday, November 15, 2007 4:41 PM<o:p></o:p> </div> <div> Subject: Re: [CAUT] Hygrometers<o:p></o:p> </div> <div> <o:p> </o:p> </div> At 12:42 PM 11/15/07, Paul wrote: <o:p></o:p> Hi List, I have a couple of those cheap  max-min thermo-hygro readers from Pianotek.  I'm not sure if they're very accurate.  <o:p></o:p> They're more accurate than the Radio Shack ones, but I don't think by much. <o:p></o:p> 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? <o:p></o:p> 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. 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. <X-TAB>        </X-TAB><X-TAB>         </X-TAB>John <o:p></o:p> <X-SIGSEP> </X-SIGSEP>------------------------------- John Musselwhite, RPT  -  Registered Piano Technician Musselwhite Piano Services - <st1:place w:st="on"><st1:City w:st="on">Calgary</st1:City>, <st1:State w:st="on">Alberta</st1:State> <st1:country-region w:st="on">Canada</st1:country-region></st1:place> Office/cel (403) 246-7717 Fax (403) 255-5268 Outside of <st1:City w:st="on"><st1:place w:st="on">Calgary</st1:place></st1:City> call Toll Free:  1-866-95-PIANO (1-866-957-4266) "Three Generations of Experience"<o:p></o:p> </blockquote> </div> </body> </html>