Frequency Divider | Electronic Project Circuits

Posts Tagged ‘frequency divider’

300 MHz Prescaler by MCT10280

A preamp that drives the CMOS counter input and a divide by 10 prescaler to extend the range of A Little More Serious Frequency Meter. The MCT10280 prescaler can be set to divide by 80, 40, 20, or 10, as a function of which pins are tied to the power supply. I set this one to divide by 10 since it is adequate for my needs, and the mental calculation of multiplying the meter reading by 10 is not taxing. One problem with the MCT10280 is that if it doesn’t have an adequate input, the output is very noisy, which shows up as counts in the couple MHz range on the frequency meter. This noise shows up if the signal amplitude the signal frequency is too low. For this reason, I only intend to use the prescaler with inputs between 10 MHz and 300 MHz.

Source:http://cappels.org/dproj/preamprescaler/preampresc.html

Related Links Circuit
Frequency Divider circuit
RF Modulator circuit

Be the first to comment - What do you think? Posted by admin - December 29, 2007 at 1:21 am

Categories: RF-Radio Frequency Tags: frequency divider, radio-frequency, rf modulator

Variable period Oscillator (CD4017)

The following CD4017 circuits have not been tested and is presented here as a possibility only. If you experiment with this circuit please send me any problems found so that the circuit can be updated.

The following circuits are designed to change the duration of each positive output pulse from the astable timer. The circuits use a CD4017 Decade Counter / Decoder to provide nine or ten steps in the cycle.

The first circuit operates with a repeating ten step cycle. Each output pulse is longer than the previous until a count of ten is reached at which time the cycle will repeat.

The second circuit has a nine step cycle that stops at the end of the cycle. The cycle is restarted or reset when the RESET input is briefly made high.

The CD4017 can be configured to give count lengths between 1 and 10. Refer to the timing diagram in the CD4017 data sheet for a better understanding of the circuit’s operation.

Source:http://home.cogeco.ca/~rpaisley4/LM555.html#21

Be the first to comment - What do you think? Posted by admin - November 1, 2007 at 3:28 pm

Categories: Oscillator generator Tags: digital circuit, digital counter, frequency divider, IC 4017

Frequency Doubler with 4011

This frequency doubler uses one CMOS quad, two input NAND gate package type 4011. The frequency doubler proper consists of an inverter IC1B, two differentiating networks R1/C1, R2/C2 and NAND gate IC1A, IC1C and IC1D function as input and output buffers. In Fig.2 exist the pulses in different points of circuit.

Source:http://users.otenet.gr/~athsam/frequency_doubler_with_4011.htm
Thank you.