Hello,
        Check out the RCA corp. in USA, for their old (1980s) CD-ROM
drives. These drives are based not on laser's but on change in capacitance
directly below the electrode, they are easily sensitive to capacitance's
of the order of fF. However RCA phased them out after the advent of
semiconductor lasers, but they still produce (were till 2years ago)
components of these drives, for customer support. You could get in touch
with them their address of personnels and catalogues are available at

HTTP://www.rca.com/

Good Luck
Amit Shiwalkar




On Tue, 23 Mar 1999, K.V.Madanagopal wrote:

> Hi!
> Are there commerical suppliers of capacitance sense ckts (transresistance
> amps) which can sense 10's of fF's (or tenths or nA's)
>
> Thanks
> Madan
>
>
>

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Amit Shiwalkar                         Dept. Of Bio-Medical Engineering.
3,Vasant,                              IIT Bombay.
Carter Road,                           Powai, Bombay-400076
Khar,
Bombay(Mumbai)-400052
INDIA.


                     Email: amits@cc.iitb.ernet.in

" Reality Is a Figment of IMAGINATION "
                                ----------- Amit Shiwalkar

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