# How to increase frequency from 50hz to 1Khz or more?

Discussion in 'Homework Help' started by Nelson2001, Apr 8, 2013.

1. ### Nelson2001 Thread Starter Member

Nov 10, 2011
27
0
I want to make RLC resonant circuit, but aI need increase the frequency to make the inductive reactance bigger!, and the q=XL/R, must be 10 0 100 times greater, to see the voltage in L or C and R. its only for learning.
I want to bearboard a RLC, but the problem is that I have 12 volts, 50HZ frequency. So the Inductance should be a bigger one.
The problem : I dont have a frequency generator, AND the inductor from the electronics shop is 1mh maximun. So the reactive inductance is XL= 2*pi*50*.001=0,314159... OHMS.
A friend told me build a circuit with a LM741 operational to increase the frequency but i dont know what to read or bibliography to look.
THANKS AGAIN

2. ### t06afre AAC Fanatic!

May 11, 2009
5,939
1,222
Ouch no please do NOT use a 741 type opamp. Use a opamp by all means. But not a relic from 1969. Take a look at this ebook. It has a good section on oscillators www.ti.com/lit/an/slod006b/slod006b.pdf

3. ### takao21203 Distinguished Member

Apr 28, 2012
3,578
463
I saw not as of today a circuit for a 12v 50 HZ bearboard.

It is in truth very hard and not be practice at all to make a RLC with smaller than lets say 3 KHZ.

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4. ### takao21203 Distinguished Member

Apr 28, 2012
3,578
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1 mH has a self resonance of 500 KHz.

The largest coils which are usually sold nowadays are 22mH or 47mH max.

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5. ### takao21203 Distinguished Member

Apr 28, 2012
3,578
463
KIA358? I have 20 here, brand new ICs. Same as LM358 I think. They work fine for some purposes.

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