frequency meter.

[antonis_x]

I don't know if this is the right place to write about this theme(tell if i had make mistake).

I have a problem:I have built a function generator with MAX038,it works very well,but now i want to built a frequency meter for this generator and i can't find a good schematic for low cost frequency meter...
the generator has a range of less than 1Hz to 20MHz...
actually a problem is that i can't find some stuff that(for example some microcontrollers)that is unprochurable in the local market..

i have heard for the ICM7216 a 'old' ferquency meter chip tat works very well but i cant find it nowhere...

P.S. SORRY FOR MY ENGLISH...

 

[Nordic]

How is that function handled by cheap multimeters?

 

[antonis_x]

please if you can,write more more analytical to be sure that i understand you..what you mean???


p.s sorry for my english...

 

[Nordic]

Many cheap multimeters have built in frequency meter... you could investigate how it is done, or if it is accurate enough, simply take a multimeter appart and build it into the equipment you want...

 

[antonis_x]

I think i'll do that.It's quite cheap,i am in a hurry to finish this generator and i don't have time to look for something else this time...
thanks for your interest...



P.S. sorry for my English...

 

[Stocker]

Have you tried searching for a frequency-to-voltage converter?

 

[I_Forgot]

It isn't terribly difficult to program a uC chip as a frequency counter. You input your signal to a schmitt-trigger input on a prescaler in a uC and run a timer that counts uC clock cycles. Each time the input signal changes state you save the counter value and reset the counter. Average several of the counted values and update the frequency display about 10 times per second, or maybe make the display update a function of the input signal frequency.

I_F

 

[RDL2004]

Here is a cheap frequency meter on eBay. You would probably need to devise some kind of simple pre-scaler for your project, probably with a range switch.

 

[jackinnj]

LM2907 or LM2917 -- go to www.national.com -- the chip costs about $1.00

it was really quite a feat of analog wizardry when the first F/V converters came out --

 

[antonis_x]

I don't like the idea for frequency to voltage converter because i think i'll not have the best accuracy i can have.I'll search for this in e-bay(they give 1Hz accuracy) and i found and another one from ELEKTOR magazine(1MHz frrequency meter),or i'll program a microcontroller.

thank you all for your interest...


p.s. sorry for my English...

 

[Nordic]

Hey Antonis, glad to see you have an idea now...

P.S. your english is fine.