Clock pulse Generator with CD4049 Circuit Diagram

If you want to generate clock with CD4049 CMOS you can do as the follow picture.The typical resister values is 100K and Capacitor is 0.01-0.1uF.The output frequency is about 1/1.1RC ___Hz. Link

Clock pulse Generator with CD4049 Circuit Diagram

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Pulse Oximeter Circuit Diagram

This circuit is a pulse oximeter, it is a medical device to indirectly measure the amount of oxygen in the blood of a person. The circuit is very simple and inexpensive to build, the sensor to be monitored only need an oscilloscope, but the case does not have an oscilloscope, here an article on how to make your pc a Oscilloscope. The operation is simple, light from an LED shines through on one side of your finger and is measured across the photo-transistor, a clothespin wood will engage the LED and the photo-transistor as a way to mount and align the sensor with finger.

The monitor circuit uses only a single IC LM324 operational amplifier. There are three basic steps, the input signal is decoupled before being pre-amplified then passes through an adjustable low-pass filter to help eliminate noise 60Hz AC and finally a further low-pass filter in parallel with amplifier.

Pulse Oximeter Circuit Diagram

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Voltage to Frequency Converter Circuits Diagram

This Simple Voltage to Frequency Converter Circuits Diagram has a 1 Hz-to-30 MHz output, 150-dB dynamic range, for a 0 to 5 V input. It maintains 0.08% linearity over its entire 71/3 decade range with a full-scale drift of about 20 ppm/°C. To get the additional bandwidth, the fast )FET buffer drives the Schottky TTL Schmitt trigger. 

Simple Voltage to Frequency Converter Circuits Diagram

The Schottky diode prevents the Schmitt trigger from ever seeing negative voltage at its input. The Schmitt`s input voltage hysteresis provides the limits which the oscillator runs between. The 30-MHz, full-scale output is much faster than the LTC1043 can accept, so the digital divider stages are used to reduce the feedback frequency signal by a factor of 20. The remaining Schmitt sections furnish complementary outputs.

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Programmable Pulse Generator Circuit Diagram

This is a simple project of Programmable Pulse Generator Circuit Diagram. Fast rise and fall times require the use of high speed switching transistors for the differential pair, Q4 and Q5 Linear ramps and sine waves may be generated by the appropriate reference input.

Programmable Pulse Generator Circuit Diagram

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Long-Interval Pulse Generator Circuit Diagram

Long-Interval Pulse Generator Circuit Diagram. A rectangular-wave pulse generator with an extremely long period can be built using only two components: a National Semiconductor LM3710 supervisor IC and a 100-nF capacitor to eliminate noise spikes. This circuit utilises the watchdog and reset timers in the LM3710. The watchdog timer is reset when an edge appears on the WDI input (pin 4). If WDI is continuously held at ground level, there are not any edges and the watchdog times out. After an interval TB, it triggers a reset pulse with a duration TA and is reloaded with its initial value. The cycle then starts all over again. As a result, pulses with a period of TA + TB are present at the RESET output (pin 10).

 Long-Interval Pulse Generator Circuit Diagram

  Long-Interval Pulse Generator Circuit Diagram

As can be seen from the table, periods ranging up to around 30 seconds can be achieved in this manner. The two intervals TA and TB are determined by internal timers in the IC, which is available in various versions with four different ranges for each timer. To obtain the desired period, you must order the appropriate version of the LM3710. The type designation is decoded in the accompanying table. 

The reset threshold voltage is irrelevant for this particular application of the LM3710. The versions shown in bold face were available at the time of printing. Current information can be found on the manufacturer’s home page (www.national.com). The numbers in brackets indicate the minimum and maximum values of intervals TA and TB for which the LM3710 is tested. The circuit operates with a supply voltage in the range of 3–5 V.

Author: Gregor Kleine Copyright: Elektor Electronics

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Project of Frequency Meter for AC line Circuit Diagram

There are specific gauges are of little use for most areas of electronics, but some are expensive and hard to find even Brazil. An example is the frequency meter AC line, it really is a measuring instrument of little or no use to most of us. We can use a frequency common adapting a cable, but for anyone working with inverters, UPS and generators, this is a primary tool.

Frequency Meter for AC line Circuit Diagram

Here a circuit meter AC line frequency super simple and easy construction that can measure the frequency of 10Hz to 100Hz at a voltage of 110 V to 240 V.
This circuit converts the sine wave output of the square wave 100k watt resistor and zener diode 1 watt 6.8V which may be a 1N3829A.



The medium is directly proportional to frequency, so it can be read in a 100mA ammeter (M1).
To calibrate the use of 60Hz known home network, set the pot VR1 to read 60mA.

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