Joe, the real problem is not the pressure sensor itself ( maybe there is a
little problem here too ) but the way in which the sensors ( temperature
and pressure ) is modifying the microwave distribution field in small
spaces ( max 10ml of sample ). You realise what's happend if a small 2mm
diameter pipe ( pressure sensor connection ) and another 1mm tick wire (
temperature sensor ) are both imersed in the cell. The microwave
distribution will be "upside-down" like the normal computed conditions.
The whole microwave field will be concentrated on these "parasites"
instead of the sample. We know that, because we had developed an imersion
microwave termographic transducer ( it get a bronz medal at the
international patents competition at Geneva, last year...)
which show us exactly what's happened inside the cell.
I have used your piston ideea Joe, but ih hasn't enough resolution at
small pressure ( near 1 atm )

regards, Vasile


On Thu, 6 Jun 2002, Scott Stephens wrote:

> From: Jinx <joecolquitt@CLEAR.NET.NZ>
> Subject: Re: [EE]: Challenge: measuring temperature and pressure inveryharsh
> environement
>
>
> >> > > but the pressure ?
> >
> >What do space probes use ? You don't get much tougher
> >than Venus. I know the tx didn't last long, but perhaps the
> >sensors help out for a while
>
>
> Diamond windows IIRC. Only lasted an hour in the high-pressure sulfuric
> acid.
>
> Scott
>
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