Alejandro:

There are pH probes available for food processing. Also, since your vinegar
is liquid, a common pH probe ( relatively inexpensive) should do.

Look at www.omega.com


Fritz


----- Original Message -----
From: "Alejandro Fubini" <alex@FUBINI.FREESERVE.CO.UK>
To: <PICLIST@MITVMA.MIT.EDU>
Sent: Tuesday, February 06, 2001 7:17 PM
Subject: Re: [EE]: Liquid Acidity Sensor


> I'm trying to test the acidity level in home brewed vinegar and thought
> maybe this would be a good way to get to grips with programming PIC's. I
> guess most sensors are not made to be stuck inside food... Oh well, I'll
> have to think up of something else to build.
>
> Thank you for your replies,
> --Alex
>
> -----Original Message-----
> From: pic microcontroller discussion list
> [mailto:PICLIST@MITVMA.MIT.EDU]On Behalf Of Gennette, Bruce
> Sent: Tuesday, February 06, 2001 5:55 PM
> To: PICLIST@MITVMA.MIT.EDU
> Subject: Re: [EE]: Liquid Acidity Sensor
>
>
> pH probes are most often used for this.
> Basically they use a special type of glass that allows the ionic activity
> (charge carriers) value in a liquid solution (usually water) to pass
through
> the wall to an electrode in a standard solution. The leakage between the
> solutions inside and outside the special glass is measured and displayed
as
> an adjusted value between 10^0 and 10^14 (actually 10^0 to 10^7 each side
of
> 10^7). Warning - the probes are expensive and easily poisoned (the glass
has
> its special properties permanently changed by reaction with a strong
> chemical).
>
> If you are only interested in testing the one type of solution - eg
chlorine
> in a swimming pool then you can measure some alternative property that is
> indicitive of the pH, such as conductivity.
>
> You'll find several PIC based conductivity probe projects on the net if
you
> search.  These also suffer from probe poisoning, but the probes are cheap
> and easy to replace.
>
> Bye.
>
> > -----Original Message-----
> > From: Alejandro Fubini [SMTP:alex@FUBINI.FREESERVE.CO.UK]
> > Sent: Wednesday, 7 February 2001 7:28
> > To:   PICLIST@MITVMA.MIT.EDU
> > Subject:      [EE]: Liquid Acidity Sensor
> >
> > Hello,
> >
> > I was wondering if anyone knows of the existence of acidity sensors. I'm
> > thinking of building a tester for liquid acidity using a PIC 16F84 and
> > some
> > sort of sensor, only I've never come accross one. Any suggestions will
be
> > much appreciated.
> >
> > Thanks
> > --Alex
> >
> > --
> > http://www.piclist.com hint: PICList Posts must start with ONE topic:
> > [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads
> >
>
> --
> http://www.piclist.com hint: PICList Posts must start with ONE topic:
> [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads
>
> --
> http://www.piclist.com hint: PICList Posts must start with ONE topic:
> [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads
>
>
>

--
http://www.piclist.com hint: The list server can filter out subtopics
(like ads or off topics) for you. See http://www.piclist.com/#topics