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Thread ID: 105114 2009-11-19 19:42:00 Electronics help prefect (6291) PC World Chat
Post ID Timestamp Content User
831650 2009-11-19 19:42:00 My son has a school science project and wants a micro ammeter the plans he has from internet say its available at the radio shack.
DSE dont seem to have one from their website product listing.
My multimeter only does milliamps he needs microamps for current produced from human body.
Does anyone know where in Auckland they can be bought
Thanks for any help.
prefect (6291)
831651 2009-11-19 19:58:00 Try Jaycar ? bonzo29 (2348)
831652 2009-11-19 20:35:00 DSE should be trusted only for toasters.
However, a cheap low range voltmeter is a passable micro-ammeter. It will have a lot more resistance than required, and calibration will be lacking, but if an indication is all that is required from a high impedance source such as the human body it will happily indicate quite small currents and indicate relative magnitude. Ohms law is your friend here.

If he wishes to satisfy some curiosity as well as get the measure of these fleeting currents, try converting the cheapo meter to a mirror type; a small piece of aluminium foil attached in place of the pointer and deflecting a focussed light beam onto a distant scale.
R2x1 (4628)
831653 2009-11-19 20:39:00 What range Rx? prefect (6291)
831654 2009-11-19 20:56:00 Try Jaycar ?
Thanks just rung them have one in Glenfield and only $11.00 thanks
bonzo and rx.
prefect (6291)
831655 2009-11-19 21:25:00 Jaycar Cat. QP-5012; 0-50 uA
or Cat. QP-5020; 0-20V, 20Kohm
R2x1 (4628)
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