# LCR Meter Basic Circuit Sample

#### Engr

Joined Mar 17, 2010
114
Hi Guys. I was looking for a circuit that can measure inductance, capacitance and resistance. A basic or simplified circuit will do. If someone has a knowledge about this circuit, I need help on this one...Thanks

Joined Jul 7, 2009
1,577
You can look up the instruction manual for the GR 1650 impedance bridge; it has schematics in it for a manual measuring system. It used variations on the Wheatstone bridge.

#### marshallf3

Joined Jul 26, 2010
2,358
$25 will get you a good LC meter from eBay, look through my previous posts. A DMM can be as cheap as$2.99 from Harbor Freight when they put them on sale and it will even give you an approximate HFE of a transistor.

#### Engr

Joined Mar 17, 2010
114
You can look up the instruction manual for the GR 1650 impedance bridge; it has schematics in it for a manual measuring system. It used variations on the Wheatstone bridge.
I was searching the internet for a copy of the manual but I only find a file containing the specs, not the manual. It would be great if you can send me a link to this manual....Thanks

Joined Jul 7, 2009
1,577

#### Engr

Joined Mar 17, 2010
114
Thanks for the link..This is very useful....

#### thatoneguy

Joined Feb 19, 2009
6,349
Capacitance and resistance are relatively simple, until you get to very large or very small values. Both are features of nearly every DMM around for low cost.

Inductors aren't as straightforward to measure, one quick trick is to use a signal generator and a meter

#### Engr

Joined Mar 17, 2010
114
Capacitance and resistance are relatively simple, until you get to very large or very small values. Both are features of nearly every DMM around for low cost.

Inductors aren't as straightforward to measure, one quick trick is to use a signal generator and a meter
The capacitance that we are measuring is around 100pF....

#### jpanhalt

Joined Jan 18, 2008
7,867

From our own (shared of course) Dick Cappels (includes code):

http://cappels.org/dproj/nlglcm/Pretty Good LC Meter Project.html
http://cappels.org/dproj/EvenBetterLCMeter/Even_Better_LC_Meter.html

Commercial/Kits
http://electronics-diy.com/lc_meter.php
http://my.integritynet.com.au/purdic/lc-meter-project.htm
http://alfaelectronics.com/shop/product_info.php/cPath/27/products_id/54
http://www.elexp.com/tst_b810.htm
http://www.peakelec.co.uk/acatalog/jz_lcr40.html

The DIY kit apparently first appeared as a 16F84 based unit. Unfortunately the links I had were all "updated" to the commercial site that now lacks the source code as best I can tell.
I think I found the code here: http://ironbark.bendigo.latrobe.edu.au/~rice/lc/index2.html

John