Tom wrote. Another scheme I've heard of is to have a smallish calibrated cup that holds maybe the equivalent of half an inch of rain. When this fills its weight causes it to spill out into a bucket, and this tilt/spill clicks some kind of counter.
That's called a tipping bucket rain gauge. They are common in home weather stations such as the one I have. Their advantage is that they don't have to be emptied. Their disadvantage is that the become inaccurate at high rainfall rates. The capacity of one bucket is 1/100 inch of rain. The rain is collected by a large funnel making the amount of water collected for 1/100 inch fairly large. Their are two buckets on the pivoting platform. When the high one gets full the whole thing overbalances and flips advancing a counter. The full bucket empties and the other one begins to fill repeating the process. The inaccuracy comes in because when the bucket assembly flips a little bit of rain is lost. At very high rates this can be significant. I know all of this because I once built a Heathkit rain gauge. I gave it to a friend when I got this new weather station. Regards. Max. K 4 O D S. Email: [EMAIL PROTECTED] Transistor site http://www.funwithtransistors.net Vacuum tube site: http://www.funwithtubes.net Music site: http://www.maxsmusicplace.com To subscribe to the fun with tubes group send an email to, [EMAIL PROTECTED] ----- Original Message ----- From: "Tom Fowle" <[EMAIL PROTECTED]> To: <[email protected]> Sent: Tuesday, March 25, 2008 1:14 PM Subject: Re: [BlindHandyMan] give em an inch and > I've seen circuits to use capacitance, but you still need > salt water since it must be conductive to form > one plate of the capacitor. You arrange a metal cover > or top over the water that forms the other plate of the capacitor and > drive it with some relatively high frequency alternating supply > and measure the current flow with an A.C.microampmeter > and calculate the reactance that changes with the height > of the water and the closing of the air space. > > Oops, you just covered over the bucket!!! > > That has been done for things like sumps and boat bilges > but not for rain gauges. > > Another scheme I've heard of is to have a smallish calibrated cup that > holds maybe the equivelent of half an inch of rain. When this fills its > weight > causes it to spill out into a bucket, and this tilt/spill clicks > some kind of counter. > > Tom > > > ------------------------------------ > > To listen to the show archives go to link > http://www.acbradio.org/pweb/index.php?module=pagemaster&PAGE_user_op=view_page&PAGE_id=33&MMN_position=47:29 > Or > ftp://ftp.acbradio.org/acbradio-archives/handyman/ > > The Pod Cast address for the Blind Handy Man Show is. > http://www.acbradio.org/news/xml/podcast.php?pgm=saturday > > Visit The Blind Handy Man Files Page To Review Contributions From Various > List Members At The Following address: > http://www.jaws-users.com/JAWS/handyman/ > > Visit the archives page at the following address > http://www.mail-archive.com/[email protected]/ > > If you would like to join the JAWS Users List, then visit the following > address for more information: > http://www.jaws-users.com/ > For a complete list of email commands pertaining to the Blind Handy Man > list just send a blank message to: > [EMAIL PROTECTED] Groups Links > > > > > > > -- > No virus found in this incoming message. > Checked by AVG Free Edition. > Version: 7.5.516 / Virus Database: 269.22.0/1342 - Release Date: 3/25/2008 > 10:26 AM > >
