A manometer works great but to read that high of a vacuum but you will need a mercury filled instrument...perhaps it is hard to find these days...when I worked in an instrument lab a guy blew all the mercury out of one...what a mess!....hazmat crew had to fix it. There are nice digital vacuum gauges as well as bourdon tube types such as made by Heise. Wallace and Tiernam makes some nice accurate gauges but very expensive but I have seen some in the surplus channels lately at reasonable prices...
On Jan 15, 10:22 am, jb-electronics <webmas...@jb-electronics.de> wrote: > Wow, Alek, I did not know this video, amazing! I have some friends who > speak Polish, I guess they can help me. Are there more of these videos? > > I have now found a reasonably priced vacuum sensor at mouser.com, it is > called SSCDANN015PA2A3, that means: Absolute pressure sensor, 0 to 15 > psi == 1 bar, 14 bit resolution, I2C interface. It costs about 25EUR, > that is quite affordable, I can build the rest of the electronics at > home, no problem with that. In fact, I have never used I2C before, but > that won't hold me back ;-). > > At the university I have made some tests with an ancient rotary pump and > it went down to 2mbar which is OK I guess. I will purchase one of these > cheap pumps used in refrigeration and test it with the university's > vacuum meter, and if it is fine, I will keep it, and if not, I will > return it. > > Best regards, > Jens > > Am 15.01.2012 16:05, schrieb Aleksander Zawada onet: > > > > > When I started, I used car light bulb as Pirani's gauge. I used my > > own glass oil diffusion pump (only 1-stage) and rotary pump. If you > > want, you can see here: > > >http://www.youtube.com/watch?v=TJ0Pm4swoOo > > > Unfortunatelly, only polish language. > > > W dniu 2012-01-15 00:42, David Forbes pisze: > >> On 1/14/12 6:30 AM, jb-electronics wrote: > >>> Hi, > > >>>> Vacuum gauges are made by Varian. There's a panel meter and a little > >>>> metal gizmo with an octal base like an old vacuum tube. Look on ebay. > > >>> thanks, I did. The actual gauges are quite pricy, maybe I can use a > >>> more > >>> ordinary pressure sensor and build a gauge of my own. > > >>> Thanks again, > >>> Jens > > >> An ordinary pressure sensor is useless for below 10 mbar, since the > >> resolution is poor. The fancy ones use an ionization sensor to get an > >> accurate reading at very low pressure. > > >> And I made a mistake - it's not Varian you want, but Hastings. > > >> Google for 'hastings vacuum' and you'll find lots of meters and > >> sensors. The meters are $150-250 and the sensors are $50-100. But > >> they work well. > > >> The other brand of vacuum gauge that we use is Pfeiffer/Balzers, but > >> they are really expensive. They go down to the microtorr level, though.- > >> Hide quoted text - > > - Show quoted text - -- You received this message because you are subscribed to the Google Groups "neonixie-l" group. To post to this group, send an email to neonixie-l@googlegroups.com. To unsubscribe from this group, send email to neonixie-l+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/neonixie-l?hl=en-GB.
