use the LM567 as a PLL to demodulate FM???

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Electricman2K5

New Member

• Feb 21, 2005

• #1

Does anyone know how to use the LM567 as a PLL to receive and demodulate an FM signal of say 40khz?

I have the LM565 but it requires -ve voltage so its inconvenient.

Thannks for any help

 

DJ_ReL@X!

New Member

• Feb 23, 2005

• #2

I wanted that too, but it is impossible. It only compares frequencies. I had to use LM565.

If you don't want to use two power supplies add an offset (half your power supply) to the input signal.

 

F

FRIED

New Member

• Feb 23, 2005

• #3

**broken link removed**
The majority of the circuit examples here show how to bias the input for single supply.

 

Sebi

Active Member

• Feb 27, 2005

• #4

LM567 commonly used as modulator-demodulator in powerline intercoms.
Work fine.

 

DJ_ReL@X!

New Member

• Feb 28, 2005

• #5

Of course it can be used as a demodulator, but only for digital signals. Electricman is talking about FM, not FSK. Am I right?

 

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Electricman2K5

New Member

• Feb 28, 2005

• #6

Lm567 as demodulator

Ive attactched my schematic Im not sure if it can be used or not i couldnt get the LM565 to work for some reason so Im trying the 567 . C\an I use the 567 instead of the 565 here ?????

 

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audioguru

Well-Known Member

Most Helpful Member

• Feb 28, 2005

• #7

Its 1uF caps are way too high in value and will make it lock only to a 40Hz carrier.