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Build a V8 Doorbell - Is the sound of a V8 engine music to your ears? This project will give you a deep-throated V8 rumble when your front doorbell is pressed___ SiliconChip Circuit Project: Doorbell Warning Switch - 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 doorbell if you are watching TV , this __
Crank Doorbell - Here is an interesting hobby circuit of a “crank” door bell! The circuit is built around a timer 555 and a musical piezo-buzzer. The circuit works off 9 volt battery supply. One 9volt PP3/6F22 compact battery is enough for powering the whole gadget. Timer IC (NE555) is wired in monostable mode to produce a time out __ Designed by T.K. Hareendran
Ding-Dong Bell - This simple and cost-effective door bell circuit is based on IC 8021-2 from Formox Semiconductors (Website address: fortech@mantramail. com). It is an 8-pin DIP IC whose only four pins, as shown...___ Electronics Projects for You
Door Knob Alarm - Many companies offer simple alarm devices for personal use in bedrooms or hotel rooms. A metal chain attached to a box holding the electronics is placed around the inside doorknob of a wood door. Anyone grabbing the knob from the outside is detected. . . Circuit by David Johnson P.E.-May, 2000
Door knock Alarm with timer - This low-cost circuit uses the piezoelectric element of a piezobuzzer as the input sensor. The piezoelectric element plate is fixed at the centre of the door wing by using a cello tape. Apply a small quantity of adhesive at the edges between the plate and the door. Extend wires about 1-1.5 metres from the piezoelectric to the circuit. __
Door Knock Beeper - In some apartment buildings and homes, not equipped with a door bell, it may be hard to hear someone knocking on the front door. The circuit below provides a means to activate a loud beeping sound inside, whenever someone knocks on the door. . . Circuit by Dave Johnson P.E.-June, 2009
Doorbell for the Deaf - This circuit provides a delayed visual indication when a door bell switch is pressed. In addition, a DPDT switch can be moved from within the house which will light a lamp in the door bell switch. The lamp can illuminate the words "Please Wait" for anyone with walking difficulties __ Designed by Andy Collison
Doorbell heard in Basement - If you can't hear your doorbell when you are in your basement try this circuit. This circuit takes advantage of the 24vac power source located near the furnace. Using a simple current transformer technique, the circuit sounds a beeper whenever the . . . Hobby Circuit designed by Dave Johnson P.E.-June, 2000
Doorbell Memory - f you’re expecting an important visitor but you just have to step out for a moment, an electronic doorbell memory can come in handy so you can see whether someone rang while you were out. Of course, you can’t tell whether it was the visitor you were expecting who dropped by then, but a call to the mobile phone of the person concerned can quickly answer that question. A doorbell memory can also save you the trouble of going to the front door (if you live upstairs) when you think you heard the bell but aren’t sure. And if you can’t buy one, then of course you can build one yourself! Read on to find out how___ Learning Electronics
Doorbell Warning Switch - 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 doorbell if you are watching TV , this __
Doorbell with Counter - This circuit uses a synthesized sound chip from Holtek, the HT-2811. This reproduces the sound of a "ding-dong" chiming doorbell. Additionally, the circuit includes a CMOS
4026 counter display driver IC to count your visitors __ Designed by Andy Collison
Doorbell with Security Feature - This doorbell system works such that when someone presses your calling bell switch during the night, not only the bell rings but the bulb connected to it also glows. In order...___ Electronics Projects for You
Doorbell-Controlled Porchlight - This add-on circuit automatically turns on your porchlight when your doorbell rings, so you can see the person ringing the doorbell at the doorstep. This also helps to guard against burglars,...___ Electronics Projects for You
Doorbell-Controlled Security Switch - One way to check whether anybody is at home is to ring the doorbell. Burglars too use this very technique. The circuit described here comes handy in such a situation. It...___ Electronics Projects for You
Doorbell-Cum-Visitor Indicator - This doorbell circuit can also give identification of the visitor to your home in your absence. When you’re home, you can use it simply as a normal doorbell. The circuit (see Fig....___ Electronics Projects for You
Door-Knock or Vibration Alarm - This is a simple circuit that activates an alarm when there is a knock on the door or there are any vibrations due to movement of heavy goods or furniture. The circuit uses readily available components.___ Electronics Projects for You
Doorphone Intercom - A simple 2 way Intercom based on the LM386386 using 8 ohm speakers __ Designed by Andy Collinson and Laurier Gendron
Electronic Canary Doorbell - This circuit is a modified "Hartley Oscillator" with a couple extra parts. T1, the LT700 (Tony van Roon's or equivalent, is a small center tapped (Tony van Roon's ct) audio transformer with an impedance of 1000 ohms at 1000 hertz. The secondary of this transformer has an impedance of 8 ohms. Usually noted as 1K:8 ct. I tried a couple other models like the red and green types (Tony van Roon's taken out of a $5 made-in-china am pocket radio) and they both work good. You may have to adjust the caps to get the sound __ Designed by Tony van Roon VA3AVR
Electronic Doorbell - This is an old project that we still use today. The chip has 12 different melodies. It is set so that each time the doorbell switch is pressed, a different tune plays. It’s quite loud. I’m not including the schematic
drawing because I don’t have one. I don’t remember how I designed these circuit boards and did not include the drawing. Perhaps I simply used the drawing that came with the chip. It was purchased from Radio Shack. This is 9-2013. The circuit was built in 1995. __ Designed by Lennie Zink
Electronic Doorbell Light - This 6V battery operated doorbell light circuit can be connected in parallel with any existing AC230V doorbell. When anyone push the doorbell switch, the bell sounds as usual and ac mains supply available across the doorbell is routed to the input of this circuit through an opto-coupler(IC1). Conduction of IC1 triggers a __ Designed by T.K. Hareendran |
