Switching Circuits
- Page 9
-
Infrared light reflected off a finger is used to activate this switch circuit..
-
-
As the only electronics engineer in my family and circle of friends, it is sometimes not possible to evade an appeal for help. This time the request came from a friendly elderly lady in a retirement home. In her room the light switch by the door and the pull....
-
This 9-minute timer switch can be used to control the light in a toilet or bathroom. The timer is started by pushing S1 and stopped by pushing S1 again. If you forget to turn it off, the controlled light will go off after nine minutes. If you need the light....
-
Feedback in public address amplifier is something that should be avoided. The ideal solution is by adjusting the microphone and the speaker position, but it`s not always possible in many situation. Using frequency shifter to change the output frequency 10Hz....
-
Nowadays a lot of intercom units are equipped with video cameras so that you can see as well as hear who is at the door. Unfortunately, the camera lens is perfectly placed to serve as a sort of support point for people during the conversation, with the....
-
This analog switch uses the 2N4860 JFET for its 25 ohm rON and low leakage. The LM102 serves as a voltage buffer. This circuit can be adapted to a dual trace oscilloscope chopper. The DM7800 monolithic IC provides adequate switch drive controlled DTL-TTL....
-
-
Here the 220V AC lamp touch dimmer circuit. By only touching this touch dimmer you are able to increase the light intensity of incandescent lamps in three stages. The touch dimmer is designed all around 8-pin CMOS IC TT8486A/TT6061A especially produced for....
-
This is a ultrasonic motion detector (or movement detector) circuit. The circuit claimed has a high movement sensitivity. Even air moving (hot air rising, wind blowing) will trigger it when the trimpot is set near the most sensitive position. The transmitter....
-
Normally home appliances are controlled by means of switches, sensors, etc. However, physical contact with switches may be dangerous if there is any shorting. The circuit described here requires no physical contact for operating the appliance. You just need....
-
Ultrasonic Switch. C ircuit of a new type of remote control switch is described here. This circuit functions with inaudible...
-
Light Switch. This is a light switch or light activated relay circuit.The relay if LDR uncoverd and relays, if LDR VR1 covered. Adjust sensitive.LED for...
-
-
Optical toggle switch using a single Chip. Using dual flip-flop IC CD4027 employ a 555 based monostable circuit to supply input clock pulses. The circuit described here obviates this requirement. One...
-
Two line intercom plus a telephone changeover switch. The circuit presented here can be used for connecting two telephones in parallel and also as a 2-line intercom. Usually a single telephone is connected to a...
-
The brightness of the surrounding light controls the function of this circuit. The light sensor used in this circuit is a light dependent resistor(LDR). This LDR is connected to the non-inverting input of the 741 opamp IC. Once the intensity of the light....
-
Driving the artery with your high-beam headlights can absolutely access your visibility, but can he a blinding hazard for added drivers. This simple ambit can be active into your headlight about-face to accommodate automated switching amid aerial and low....
-
-
-
Based on NE555 this circuit turns on and off the IC output by a momentary switch. In other words it works as a mechanical latching relay, but the circuit backs to the start condition when you switch off the power supply. This feature is often required in....
-
This is the circuit diagram of a light activated switch based on National Semiconductors comparator IC LM 311 and a LDR. The circuit is based on a voltage comparator circuit wired around IC 1. The non inverting in put of IC1 is given with a reference voltage....
-
-
This article describes the proposed solution for a 200 W Power Supply using the FSFR2100 Fairchild Power Switch (FPS). The input voltage range is 90 265 VRMS and there are six outputs with...
-
This circuit is connected directly to a 220V home electrical installations. LOAD on the schematic diagram above, is an electronic device with 220V AC current consumption...
-
This circuit will light a lamp at a remote location when the doorbell switch is pressed. This circuit should only be used with the solenoid type doorbells, the electronic type that play tunes will not work here. It is quite easy to miss the sound of a....
-
-
This simple device allows two computers to share a single USB printer or some other USB device, such as an external flash drive, memory card reader or scanner. A rotary switch selects the PC that you wish to use with the USB device, while two LEDs indicate....
-
My vintage (62 year old) pole light has always been controlled by a timer ”a source of continual frustration due the requirement of readjustment for the ever-changing seasons. However, after knocking it over (I backed my car into it ), I decided it was time....
-
This wireless remote control switch production is relatively simple. All components parameters we are testing is complete. Reader component parameters we provide installation can be completed in the production of the first resistive and capacitive components....
-
The 1-Wire Net, or MicroLAN (by Maxim-Dallas), is a simple way to connect slow devices (such as sensors, relay drivers, switches, and so on) using simple components. These components contain the 1-Wire protocol handler, some type of interface to the external....
-
The transmitter part of the circuit is build around IC1(NE 555). The IC1 is wired as an astable multi vibrator operating at 40KHz. The output of IC1 is amplifier the complementary pair of transistors ( Q1 & Q2) and transmitted by the ultrasonic transmitter....
-
An explanation of how the thing should work. The TPS_EN line is low at first. Since it is pulled down by a 10k pull down resistor(not shown in the schematic). When the user presses S2, the mosfet Q2 turns on because ground is applied to its gate. which....
-
-
I have a copper mesh (10cm x 10cm square) in a vacuum chamber connected to a BNC connector by a 24-cm-long copper wire. The goal is to switch the mesh voltage (referenced to ground) from 8 V to ~0 V quickly. (This will switch the electric field in the....