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can anyone provide me with some schematics for a function generator with only a 147.7 square wave AC signal? Answered

can anyone provide me with some schematics for a function generator with only a 147.7 square wave AC signal? and im trying to make a it as small as possible

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steveastroukBest Answer (author)2014-01-14

If this is for "wireless power", just use a 555 timer.

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tykora (author)steveastrouk2014-01-18

so if you could get me a schematic of how I could use it

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steveastrouk (author)tykora2014-01-18

Take a look here:

http://freespace.virgin.net/matt.waite/resource/ha...

If R1=4.7K and R2=2.7K and the cap is 1nF you should be near enough. You can use trimmers for R1 and get the frequency bang-on

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tykora (author)steveastrouk2014-02-09

an actual circuit schematic would be more helpful

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steveastrouk (author)tykora2014-02-10

That WAS an "actual circuit". Plug in the values I worked out, and possibly put a transistor there to drive your coil.

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tykora (author)steveastrouk2014-02-11

oh :P (this is why I ask for help)

thx I couldn't recognize it

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tykora (author)steveastrouk2014-01-16

everyone keeps telling me that but I haven't learned enough yet to but a schematic together yet

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Josehf Murchison (author)2014-01-14

See helps to be concise.

Try this built right the circuit is about the size of a match box.

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tykora (author)Josehf Murchison2014-01-18

there are no 147.7kHz crystals or 0.1477MHz

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Josehf Murchison (author)tykora2014-01-18

If you cant find a 147.7 try these.

I know you can find 147.5 on the net add a .2 and mix giving you a 147.7

Go higher and PMW down.

Go higher and counter down.

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tykora (author)Josehf Murchison2014-02-09

ive been all over the web still cant find any that add up to the frequency im looking for

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Josehf Murchison (author)tykora2014-02-09

Try these people

http://www.iqdfrequencyproducts.com/

I got this datasheet on this crystal from them.

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tykora (author)Josehf Murchison2014-02-09

yah.. cant find them on there either

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Josehf Murchison (author)tykora2014-02-09

The crystal in the datasheet goes from 30 to 180 kHz

Just order one in 147.7 kHz

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tykora (author)Josehf Murchison2014-02-09

it wont let me create an account to order one

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tykora (author)tykora2014-02-09

and there all out of stock

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Josehf Murchison (author)tykora2014-02-10

Well if you can’t get a crystal get a SN74LS629 voltage controlled oscillator and adjust it to 1477000 Hz then run the 1477000 Hz through a decade counter like a 4017 to give you a 147700 Hz frequency.

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Josehf Murchison (author)2014-01-14

Now here is a silly question 147.7 what?

Hz, kHz or MHz.

The thought just struck me be concise or you may not get the answer you want.

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steveastrouk (author)2014-01-14

How accurate does the output have to be ? Can you make that frequency from dividing a standard crystal frequency by an integer ?

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Steve 147.7 what?

He didn't say.

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It struck me that is a standard crystal.

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Josehf Murchison (author)2014-01-13

That is a very tight frequency.

You can make it with a 555 timer.

But no matter what way you make it you will need a oscilloscope for fine tuning.

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...unless its crystal locked.

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