# Frequency multiplier

1. Feb 6, 2010

### Truthlover

Hi everyone, I just want to know if anyone here have a schematics to build a frequency multiplier. All I have see for the moment is multiplier with a factor of 2. I'm searching a factor 78 frequency multiplier. Also if it exist in a chip i would like to konw it to.

Thanks

Last edited: Feb 6, 2010
2. Feb 6, 2010

### Bob S

The first PLL / frequency multiplier chip (I think) was the NE565 chip in the early-mid 1970's. A block diagram of a NE565-based frequency multiplier is shown in
In your case, the frequency divider is by 13 by 3 and last by 2. I put the divide by 2 last so that the NE565 gets a 50% duty cycle square wave. To see inside the NE565, see
http://www.alldatasheet.com/datasheet-pdf/pdf/118262/ETC/NE565N.html

Bob S

3. Feb 6, 2010

### waht

What is the frequency you are trying to multiply?

4. Feb 6, 2010

### Truthlover

it's variable from 1Hz to 20 Hz to get at the output 78Hz to 1560 Hz

5. Feb 6, 2010

### Averagesupernova

There are several ways to do this depending on how accurate you need it to be.

6. Feb 6, 2010

### Truthlover

I don't need a high accuracy. $$\pm$$ 2 Hz at the output is good enough for me.

7. Feb 8, 2010

### Truthlover

he's there someone here

8. Feb 8, 2010

### Staff: Mentor

What about Bob's suggestions in post #2?