HI V., More careful reading of your last post.
I got my venerable Spectronics 20, a college quant. analysis course grade and good general purpose unit used for 415.91 whatever-they-are from Coast Scientific. I have about another 700 in glassware and other science-like doodads. The Hach reagents cost about 0.55 per test. Once you get it down, it is just Joy of Cooking. God Bless Irma R. I can do a test in about 20 minutes, and it takes the spec about 15 to warm up. It has hit a Hach ACS grade solution of AgNO3 diluted to 4 PPM right on the button every time I check it. I mean 4.0. I don't know what is happening a couple of digits over, but who cares... They turn up on the web from time to time. There are really precise and exotic used ones available if you have about three times the bux, as the big guys want the hottest/latest, and dump perfectly good instruments for cheap. I have a bunch of used lab equipment links. You are hooked. Santa Fe has great weather and sky. Bummer, though, if Los Alamos blows, we are right downwind. And there is lots of black ops in the hills..."transdimensional hyper-intelligent soulless lizzard overlords hiss and slither at the edge of your cactus-fractured mind- shadow...." Man! it is late. James Osbourne Holmes [email protected] -----Original Message----- From: Victoria Welch [SMTP:[email protected]] Sent: Friday, September 17, 1999 12:24 AM To: [email protected] Subject: CS measurements ?! James and Ian, > [ ... ] > I have become accustomed to using PPM because that is what most everyone on > the list uses. I don't have a direct formula to convert mS to PPM, but I > will get one. My meter displays either. If you have a formula to convert PPM to mS, I would appreciate it if you could pass it along. I now have the Hanna TDS and would like to make it as useful (or potentially so) as possible. > Microsiemens are a measure of conductance; it is the Ohm---unit of > resistance, upside down; the reciprocal or 1/Ohms. [ ... ] Hummm, it might be iteresting to see if my computed resistance will match the TDS value when computed that way. Just a quick computation from some of my data came out to a finished mS of 0.00011626 (1/8601), maybe it doesn't work that way...?!? > Send the water and some of your silver; I will do a PPM test on both the > water and the sol. For a limited control, you could also have Bob Berger > test it. I am, first off, courious as to what you use to get the actual PPM reading. Device, manufacturer, cost, supply costs? thoughts and comments? If you don't mind me asking. This not knowing is driving me to drink (fortunately it is CS I am drinking :). In the process, if you do testing, what are your rates? > Santa Fe > New Mexico Loved the area - hated the economy. The Pojaque(sp?) were a real thrill as well :-/. Got to visit the old governers place down on the square and in general explore the area and thoroughly enjoyed it. What an archeological paradise :)! After a few days there I could breath again :-). Thanks and take care, Vikki. -- Victoria Welch, WV9K, DoD#-13, Net/Sys/WebAdmin SeaStar.org, vikki.oz.net #include <coffee.h> "Walking on water and developing software to specification are easy as long as both are frozen" - Edward V. Berard. Do not unto others, that which you would not have others do unto you. -- The silver-list is a moderated forum for discussion of colloidal silver. To join or quit silver-list or silver-digest send an e-mail message to: [email protected] -or- [email protected] with the word subscribe or unsubscribe in the SUBJECT line. To post, address your message to: [email protected] List maintainer: Mike Devour <[email protected]>
