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Products => Test Equipment => Topic started by: dave_j_fan on March 15, 2015, 03:31:50 pm

Title: 4$ LC meter -with 555 may be
Post by: dave_j_fan on March 15, 2015, 03:31:50 pm
i Have recently tested this L -meter

http://apexys-toan.blogspot.in/2011/02/ne555-based-inductivty-meter.html (http://apexys-toan.blogspot.in/2011/02/ne555-based-inductivty-meter.html)
It works very nicely in uH range ::) ::)
with some  tweak did 10mH range too

I suppose with constant L we can use this a cap meter
I like as it is vv simple , all ppl have a n xtra 555 and sm spare NPNS
There is an issue , if no coil is there it over shoots ....may damage analogue meter :'( :'(


i came up with a preventer ckt  as in the attachment ..please share your views
Title: Re: 4$ LC meter -with 555 may be
Post by: Napalm2002 on March 15, 2015, 03:53:38 pm
Cool I like building stuff
Title: Re: 4$ LC meter -with 555 may be
Post by: dave_j_fan on March 15, 2015, 05:58:10 pm
the preventer is not able to fully zero the meter .. will try volt divider to do that   :-//