Broadband Random Noise Generator

Broadband Random Noise Generator Circuit

This circuit is normally necessary in testing any sort of electronic methods for example filter, audio, or RF communication. The circuit introduced right here generates an RMS amplitude regulated noise source with selectable bandwidth. This circuit is work depending on op amp. This will be the figure with the circuit. Look at the schematic of Broadband Random Noise Generator Circuit above.

With 1 KHz to 5 MHz ten years ranges selectable bandwidth and 300mV RMS output, this noise generator is suitable for wide range of software. Noise is created by D1 that is AC coupled to A2, an amplifier with broadband acquire one hundred. The output of A2 is fed to a effortless selectable low-pass filter. The filter’s output is applied to LT1228 operational trans-conductance amplifier A3. A3’s output feeds current feedback amplifier LT1228 A4. A4’s output, which can be also the circuit’s output, is sampled by the A5-based gain manage configuration. This closes a gain manage loop to A3. A3’s ISET current controls gain, permitting overall output degree manage.

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Two Speed Contactor DC Motor Controller Circuit

The simplest of all motor controllers (besides a straight on/off switch) is the contactor controller. I designed this contactor controller for use in my electric scooter project. It is based around three 12V relays, two 12V batteries, two switches and of course a motor. Having no silicon to “fry”, it is quite reliable and robust. A contactor controller works by rearranging the two (or more) supply batteries between series and parallel. This gives the motor a slow speed (batteries in parallel, current adds) and a fast speed (batteries in series, voltage adds). This assures that both batteries are discharged equally. When the circuit is “at rest”, the batteries are connected in parallel, which allows easy recharging.

Notes

1. S1 closes K3 and thus causes M1 to operate. S2 activates K1 and K2, reconfiguring the batteries for series operation and thus causes M1 to operate at “fast” speed.

2. B1 and B2 should be chosen based on the current requirements of M1. Often, sealed lead-acid type batteries are available at local suppliers for surprisingly low prices. These batteries are ideal for things such as scooters, go-karts, etc.

3. The relays are standard automotive type relays, available cheaply from any auto parts store.

4. Your motor will depend on your requirements. 12V motors will normally run fine at 24V, and vice versa.

5. You will notice that in series mode, all three relays only pull power from B2. This is because the relays have 12V coils, and it is impossible to switch the batteries from series to parallel and keep power to the coils at the same time. This does, however, mean that B2 is discharged slighty before B1. This should normally not be an issue unless the batteries are being drained completely “dead”. Draining a battery dead is not good for it in any situation, and should be avoided. If you wish, you can use a small 12V battery to run the relays separately.

6. You can add two more speeds to this controller using the schematic below. It connects at points A and B shown above on the controller schematic.

Parts

Part	Total Qty.	Description	Substitutions
K1, K2, K3	3	12V 30A SPDT Relay (See Notes)
S1, S2	2	SPST Switch or Button
B1, B2	2	12V Battery (See Notes)
M1	1	12V or 24V Motor (See Notes)
MISC	1	Case, Wire, etc.

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Counter Wall 7 Segment Circuit Diagram

This simple counter can be used to count pulses, as the basis for a customer counter (like you see at the doors of some stores), or for anything else that may be counted. The circuit accepts any TTL compatible logic signal, and can be expanded easily (see Notes).

Notes
1. All pulses to be counted are to be TTL compatible. They should not exeed 5V and not fall below ground.

2. You can add more digits by building a second (or third, or fourth, etc…) circuit and connecting the pin 11-6 junction of the 74LS90 and 74LS47 to pin 14 of the 74LS90 in the other circuit. You can keep expanding this way to as many digits as you want.

Part	Total Qty.	Description	Substitutions
R1-R7	7	470 Ohm 1/4 Watt Resistor
U1	1	74LS90 TTL BCD Counter IC	7490,74HC90
U2	1	74LS47 TTL Seven Segment Display Driver IC	7447,74HC47
DISP1	1	Common Anode 7 Segment LED Display
MISC	1	Board, Sockets For ICs, Wire

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Stepper Motor Pulse Generator with 555

The 555 Stepper Motor Pulse Generator kit will support you together with the pulse needed to drive your favorite DC Servo Motor application. This kit uses the well-known 555 timer IC for creating the Stepping Pulse.
Quick Overview
# Input : 5 to 12 VDC @ 25 mA
# TTL/CMOS interfaceable
# Jumper selectable two speed operation
# Onboard preset to vary the frequency
# Power-On LED indicator
# Terminal pins for easy interfacing of the kit
# Four mounting holes of 3.2 mm each
# PCB dimensions 39 mm x 37 mm

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Lightning Detector Circuit

This Do-it-yourself lightning detector circuit can be a especially sensitive static electricity detector which can supply an early warning of approaching storms from inter-cloud discharge properly prior to an earth-to-sky return strike takes location. An aerial (antenna) formed of the brief duration of wire detects storms inside a two mile radius. The circuit emits an audible warning tone from a piezo buzzer, or flashes an LED for each discharge detected, providing you advance warning of impendig storms so that precautions may be observed.

The primary characteristic inside the lighting detector is the circuit’s ability to be set near to self-oscillation, with its leisure optimised via the bias resistor values demonstrated within the circuit diagram. The oscillator is dc coupled and feedback is routed through the collector of TR1 towards the base of TR2, whilst the overall loop acquire is set using the multiturn(12, eighteen or 22) preset VR1.

Lightning detector circuit establishing

To create the lightning sensor, change preset VR1 for oscillation by monitoring test point TP1, which must be at roughly 7volts peak-to-peak. Test level TP2 should be at +6V dc. Now readjust VR1 back again a bit to quit oscillation; use a screwdriver to touch the aerial-side of C1 a variety of occasions; the alarm ought to sound for one or two seconds then stop. If it continues, create a extremely tiny adjustment back again and recheck. The other technique is to electrostatically cost a plastic ruler after which draw your finger shut to discharge, about two meter away through the aerial.

Driven from a nine volts battery the lightning detector circuit consumes about 600 uA in standby. Powered continously it could supply a fantastic yr of uninterrupted monitoring. When sounding the alarm, the current will rise to 4mA based on the low current sounder WD1. A minimal three volts system is required for a great output level and it is going to create a “pinging” alarm to warn in real time of any electrostatic pulse activity.

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CD4001 Simple Alarm Circuit For Motorcycle

Simple Alarm for motorcycle with a CD4001

This is a simple alarm circuit for a check with a 4001. You can use it to protect our home, motorcycle, car or any other application that comes to mind. In this circuit you will make a computer simulation with Livewire and then design the printed circuit Kicad.

OPERATION
SW1 is a normally closed switch when pressed triggers the flip-flop formed by the two NOR gates of the CD4001 and remains in that state for a time determined by the time constant of R5-C2. This time is the one who keeps the relay RL1 and operated by its two contacts that we investors will control two loads, for example a siren and a light or any other that we connect to P3 and P4.
After that time elapsed, the relay disconnects the circuit will soon be the alarm to be triggered again.

We can replace the switch Sw1 a PIR motion sensor, an infrared barrier, a smoke detector, gas detector, a magnetic sensor, a panic button or other device to act as a switch closed and opened fire at the alarm.

PRINTED CIRCUIT DESIGN

For the circuit we can only practical substitute for a preset R5 (RV1) so you can easily adjust the monitor while the charges.

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Phase Delay Network for 3D Audio Enhancement

3D enhancement is needed to create a fully 3-dimensional sound for most stereo multimedia products. Usually, simple phase-delay circuits is used to produce a widening effect on the perceived sound field. However, there is transaural acoustic crosstalk effect. The following figure shows transaural acoustic crosstalk effect and schematic diagram of simple phase-delay circuits :

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