code to control frequency

[adison]

Hallow friends
I have variable frequency and I want to put a controller that if the frequency over
150 HZ than it give on "1" logi to other electronic circuit if the frequency under 150 HZ than the controller give off "0" logi
I search codes that sample the frequency and give the orders according to the frequency
I need to supply the right voltage and to choose the right switch
I search in google and find this article
http://www.edn.com/article/CA54576.html#ref
VCO is device that give varible voltage in respect of changes in frequency

Thanks
adison

[adison]

H-E-L-P
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H-E-L-P
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