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From: kenny@m.cs.uiuc.edu
Newsgroups: sci.electronics
Subject: Re: Freq. and Cap. meter questions
Message-ID: <21000092@m.cs.uiuc.edu>
Date: 30 Aug 90 17:50:00 GMT
References: <33045@unix.cis.pitt.edu>
Lines: 15
Nf-ID: #R:unix.cis.pitt.edu:33045:m.cs.uiuc.edu:21000092:000:555
Nf-From: m.cs.uiuc.edu!kenny    Aug 30 12:50:00 1990


>	Is there a chip or hybrid that will convert frequency
>	(hopefully linear) to volts (or ohms)?

Drive a 555 timer wired as a monostable.  Each positive-going
transition of the signal gets a HIGH output for a specific amount of
time.  Integrate the result, and you've got a frequency meter.

For a capacitance meter, put the capacitor under test into the
control circuit of a 555 astable.  The output frequency is in inverse
proportion to capacitance, and you can take it from there.

Kevin, KE9TV
kenny@cs.uiuc.edu
but moving to ke9tv@nrtc.northrop.com