What is the smallest voltmeter?
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From: Peter Bennett on 31 Jan 2007 21:49 On Wed, 31 Jan 2007 16:03:16 -0500, "Bruce W.1" <sorry(a)noDirectEmail.com> wrote: >David L. Jones wrote: >> >> Less than 1" wide: >> http://au.farnell.com/jsp/endecaSearch/partDetail.jsp?SKU=9932909 >> Standard 200mV FSD, just make your own input scaler. >> >> Dave :) >> > >================================================= > >Expensive little guy isn't it? Newarkinone shows the price as Can$27.52 - wonder what price units that Farnell site uses? -- Peter Bennett, VE7CEI peterbb4 (at) interchange.ubc.ca new newsgroup users info : http://vancouver-webpages.com/nnq GPS and NMEA info: http://vancouver-webpages.com/peter Vancouver Power Squadron: http://vancouver.powersquadron.ca
From: David L. Jones on 31 Jan 2007 23:53 On Feb 1, 12:49 pm, Peter Bennett <pete...(a)somewhere.invalid> wrote: > On Wed, 31 Jan 2007 16:03:16 -0500, "Bruce W.1" > > <s...(a)noDirectEmail.com> wrote: > >David L. Jones wrote: > > >> Less than 1" wide: > >>http://au.farnell.com/jsp/endecaSearch/partDetail.jsp?SKU=9932909 > >> Standard 200mV FSD, just make your own input scaler. > > >> Dave :) > > >================================================= > > >Expensive little guy isn't it? > > Newarkinone shows the price as Can$27.52 - wonder what price units > that Farnell site uses? I posted the link to the Australian Farnell site, so that price is in Aussie dollars Dave :)
From: Yukio YANO on 1 Feb 2007 00:36 Bruce W.1 wrote: > > > This will be part of a 12V bicycle light system. It will mount in a > small box, probably on the handlebars. It's measurement range should be > about 8 to 20 volts. > > > Does anyone know of a really tiny voltmeter? > > Thanks for your help. Why not re-engineer the whole system ! Replace the Headlight (bulb) with a Multi-Ultra Bright White LED Array. They don't burn out or drop filaments and require less battery power and will operate on weak batteries, thus eliminate the need to closely monitor the battery Voltage or troubleshoot a no Light Output Condition. Same story for the tail-light ! Multi Red LED Array. All for the price of any DVM. Yukio YANO
From: David L. Jones on 1 Feb 2007 02:43 On Feb 1, 8:03 am, "Bruce W.1" <s...(a)noDirectEmail.com> wrote: > David L. Jones wrote: > > > Less than 1" wide: > >http://au.farnell.com/jsp/endecaSearch/partDetail.jsp?SKU=9932909 > > Standard 200mV FSD, just make your own input scaler. > > > Dave :) > > ================================================= > > Expensive little guy isn't it? My battery pack (12 C-cells) exceeds its > [14VDC] voltage rating. > > BTW, I'm also building a Pulse Width Modulation circuit so I don't fry > my 12VDC lightbulbs. This voltmeter will monitor its input and output > voltage. I'm with the others on this, re-thinking what you actually need is probably a good idea. I can't see any benefit of having an LCD display for the pack voltage, esp at night when you'll need to backlight it, and it could be distracting. If you simply what to know when the batteries are getting low then a simple single (or multiple) "low batt" LED will do. Use a DC-DC converter to give you a constant brightness on your lamp, and maximize the use of battery capacity. Are you using primary Alkaline cells or rechargables? Dave :)
From: pLaNiX on 1 Feb 2007 05:17
On Jan 31, 8:45 pm, "Bruce W.1" <s...(a)noDirectEmail.com> wrote: > I'm looking for the very smallest -- panel mount -- LCD voltmeter. My > Google searches have been dissapointing. The smallest I could find is > about 2" wide. > > This will be part of a 12V bicycle light system. It will mount in a > small box, probably on the handlebars. It's measurement range should be > about 8 to 20 volts. > > A voltmeter is not complicated. I would think that one could easily be > made in a 1/2" square. > > Does anyone know of a really tiny voltmeter? > > Thanks for your help. You can build one using one pic ADC ch. but you must set vref- 8V and vref+ 20V or you can just divide voltage range to 0-5 V. you can read the measurement with two 7 segment. google "voltmeter with pic" tags this shoud help. |