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Dancing LEDs redcircuits - A LED sequencer, following the rhythm of music or
speech 9 Volt Battery-operated portable unit (added 9/04) |
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Dark-activated LED or Lamp Flasher - This circuit adopts the rather unusual
Bowes/White emitter coupled multivibrator circuit. The oscillation frequency is about
1Hz and is set by C1 value…..(electronic design added 6/07) |
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Descrete Multistage Light Sequencer - The drawing below illustrates a multistage
light sequencer using descrete parts and no integrated circuits. The idea is not new
and I hear a similar circuit was developed about 40 years ago using germanium
transistors. The idea is to connect the lights so that as one turns off it causes the
next to turn on, and so forth. This is accomplished with a large capacitor between
each stage that charges when a stage turns off and supplies base current to the next
transistor, thus turning it on. Any....(circuit added 05/09) |
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Dice - Press the push switch to 'throw' the dice: this makes the circuit rapidly
cycle through the dice numbers so that an effectively random dice number is displayed
by the LEDs when the push switch is released....Designed by John Hewes (circuit added
06/07/08) |
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Disco Lights - software and hardware for controlling disco lights from your PC
(added 4/02) |
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Discrete Version Of The LM3909 Oscillator IC - This page features a replacement
circuit for the LM3909 LED Flasher / Oscillator using discrete components. The circuit
is functionally the same as the integrated LM3909 but has a minor variations in values
of the components used....(electronic circuit added 7/03) |
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DMX lighting & special effects - (electronic circuit added 05/07) |
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Dual Alternating Flashing Light Circuit - (electronic circuit added 4/05) |
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Dual LED Flasher - Some useful circuits using the LM555 IC. Scroll to find
the Dual Led Flasher circuit (11/06) |
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Dual Tandem Flashing Light Circuit Powered by a 9 Volt Battery - This circuit is
powered by a 9 volt battery, suitable for warning lights on a tall structure.
(Personally, I can't recommend you buy anything but the Rollins Railroad Designs kit;
for $4.00 you can't go wrong. The 555 IC is about $1.50 by itself at Radio Shack). If
you choose to buy all the parts yourself, realize you need ONLY two LEDs, not two of
each; you should be able to mix and match colors.....(electronic circuit added 4/05) |
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Dummy Alarm - This project makes a superbright LED flash briefly once every 5
seconds to imitate the indicator light of a real alarm. The circuit is designed to use
very little current to prolong battery life so that it can be left on permanently.
This is a simple project, ideal for a beginner.....Designed by John Hewes (circuit
added 06/07/08) |
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Eight LEDs Random Flasher - This project flashes eight LEDs in an apparently
random manner. It uses a 4026 combined counter and display driver IC which is designed
for driving 7-segment LED displays. The sequence is not really random because seven of
the LEDs would normally be the display segments, the eighth LED is driven by an output
that is normally ....(circuit added 06/07/08) |
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Emergency Strobe Flasher Generates 250V - 08/05/99 EDN-Design Ideas: Figure 1
shows a complete circuit for an emergency lamp that operates from a 12V automotive
battery. The xenon flash tube requires a 250V-dc anode voltage and a 4-kV trigger
pulse. To generate the 250V dc, IC1, a switching regulator controller, and T1, a
standard Versa-PAC transformer, operate in the discontinuous-flyback.....(design idea
added 1/06) |
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Expandable 16 Stage LED Sequencer - The circuit below uses a hex Schmitt Trigger
inverter (74HC14) and two 8 bit Serial-In/Parallel-Out shift registers (74HCT164 or
74HC164) to sequence 16 LEDs. The circuit can be expanded to greater lengths by
cascading additional shift registers and connecting the 8th output (pin 13) to the
data input (pin 1) of the succeeding stage. A Schmitt trigger oscillator (74HC14 pin 1
and 2) produces the clock signal for the shift registers, the rate being approximately
1/RC. Two additional Schmitt Trigger stages are used to reset and load the registers
when power is turned on. Timing is not critical,...(circuit added 7/02) |
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Fake Car Alarm Light - Whenever the car’s ignition is turned off, this circuit
activates a flashing LED, which can be positioned to appear as an active alarm system.
(added 7/06) ….(designed by David A. Johnson) |
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Fancy LEDS - The idea of this project came from my youngest son. He was dreaming
of a small tool able to write symbols or pictures on a screen. As a graphic LCD (even
bought at Crownhill :) ) was too expensive (or too easy??), the solution adopted was
to pilot a matrix of Leds. This way, ....(project added 07/07/07) |
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Fantastic Atom Expander (Aaron Cake) - "exploding atom" effect using 98 LEDs
(electronic circuit added 04/03/02) |
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Fine Control SuperBright LED Pulser - Four timing controls, 12V supply.
Suitable for Halloween or Christmas props. (added 6/07) |
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Flash Slave Trigger (Aaron Cake) - Flash slaves are used when you need to
supplement1-flash unit with1-or several more. This slave trigger simply triggers those
other units. It does this by "seeing" the first flash (using a phototransistor) and
triggering the other flashes a few microseconds later. The sensitivity of the circuit
is adjustable to compensate for ambient light or dimmer than usual master flashes.
(added 5/02) |
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Flashing Beacon - (electronic Circuit / Schematic added 10/04) |
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Flashing Birthday Heart - This circuit was made for my wife's birthday. It is
capable of flashing five strings of LED's with different frequencies. It also has a
connector for an 8 Ohm loudspeaker and two connectors for the small PCB's that are
contained in musical greeting cards. In this way the circuit will play alternatingly
two room filling tunes at regular time intervals. After a w....(electronic design
added 6/07) |
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Flashing Flashlight (Stepan Novotill) - Pretty nice design for a cheap consumer
grade flashlight. The power switch was not exactly as shown since there was an option
to have the lamp on solid. (added 2/05) |
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Flashing Heart - This circuit was made for my wife's birthday. It is capable of
flashing five strings of LED's with different frequencies. It also has a connector for
an 8 Ohm loudspeaker and two connectors for the small PCB's that are contained in
musical greeting cards. In this way the circuit will play alternatingly two room
filling tunes at regular time intervals. After a w....(electronic design added 6/07) |
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Flashing High Intensity LED 3rd Brake Light - This circuit to make a flashing3rd
brake light assembly was designed to be easy to locate all the needed components and
reasonably in expensive to build. (added 6/06) |
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Flashing LED - This simple project makes a good low-cost first project to check
your soldering skills and learn to identify common components. The LED flashes at
about 3Hz (3 flashes per second).....Designed by John Hewes (circuit added 06/07/08) |
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Flashing LED Advertising Badge #1 - I have seen numerous flashing light badges at
trade shows and conventions. They are often handed out as gifts to promote some
business. The devices often use inefficient circuits, which cause the battery power
source to be quickly depleted. My circuit is simple but efficient enough to provide
months of continuous LED flashing. It also has a tiny push-button switch to turn on
and off the light flashing, extending battery power. ….(designed by David A. Johnson) |
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Flashing LED Advertising Badge #2 - This circuit is similar to flashing LED
advertising badge #1. . It uses a CD4013 dual D Flip/Flop IC. The
74HCT74 IC in #81 does not always work. As in #81, a single lithium battery will
provide months of continuous LED flashing. It also has a tiny push-button switch
to turn on and off the light flashing. ….(designed by David A. Johnson) |
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Flashing LED Power Indicator Draws Low Current - This circuit flashes a power
indicator LED to keep the average current low. ….(designed by David A. Johnson) |
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Flashing LED with PIC12F629 - This is the first example that you should to know
how to set output pin. In this example, GPO is set as an output. LED1 will be turn-on
when GP0 is set high and LED1 wiil be turn-off when GP0 is set low. This example use
4MHz internal clock. ….(electronic schematic added 11/08) |
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Flashing LED-based Solar Engine - Voltage-Controlled Solar Engine: This design
uses a flashing LED to determine the solar engine's voltage trip level. (added
11/05) |
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Flashing Light Circuit 1 - (electronic circuit added 4/05) |
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Flashing Light Circuit 2 - (electronic circuit added 4/05) |
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Flashing Light Circuit 3 - (electronic circuit added 4/05) |
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Flashing neon christmas lights - This flashing set of neon Christmas lights will
make an attractive decoration for any time of year. Bl is made up of ten 9-V
transistor radio batteries in series. The battery life can be measured in
months….(electronic design added 6/07) |
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Flashing Neons NE 2/NE 51 - In this circuit, one, two or three neon indicator
bulbs can be made to flash in sequence at rates determined by the R and C values. In
the single stage circuit, using one lamp, the capacitor charges through the resistor
until the ionization potential of the neon is reached (about 70 volts) and....(added
4/02) |
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Flashing Rear End Devicefor DCC Systems - (electronic circuit added 7/03) |
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Flashing Road Barricade - This design has a low duty cycle to preserve battery
life and underdrives the cold filament to extend bulb life (added 2/05) |
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Flashing/Pulsing third Brake lite for cars - (Tony van Roon's electronic circuit
added 4/05) |
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Flashing-Cum-Running Light - (electronic Circuit / Schematic added 10/04) |
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Flashlight Timer - A nice design which even turns off if the pushbutton is held
depressed or jammed a long time. Not re-triggerable while the light is still on though
(added 2/05) |
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Flashy Christmas Lights - (electronic circuit added 10/05) |
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Fleapower flasher Draws less than 50 µA - 01/23/03 EDN-Design Ideas: Some
applications require a circuit to indicate that a battery's voltage has fallen below a
certain value. However, if you don't frequently check the indicator, the low-battery
indicator itself can easily discharge the battery. The circuit in Figure 1 indicates
when the battery voltage has dropped below a preset value.....(design idea added 1/05) |
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Flicker Lamp - Having bought a cute little ‘paraffin lamp’ from a cut price shop,
I decided to make it a little more interesting. Its battery powered of course but its
continuous shine and simple on / off ‘wick control’ did not make for anything like a
close simulation of the real thing. So, I replaced the on / off control with a
variable potentiometer and I added flicker!.....(added 04/04/04) |
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Flickering Fire Effect - This simple circuit uses four low-Wattage colored bulbs
and four fluorescent lamp starters to make nice flickering flame effect. (added 4/02) |
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Flickering Fire Light - This may well be the world's only discreet logic circuit
to generate truly random output. It makes an excellent candle flicker light for your
Halloween pumpkin, and looks much more authentic than a shimmer light wherever a good
a simulated flame effect is required. I do not guarantee the accuracy or safety of any
information herein. (added 2/05) |
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Flickering Lights - Halloween flickering lights (electronic circuits added
11/06) |
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Flip Flop Circuit - In this project we examine one of the most valuable circuits
to be invented, the flip flop. Originally it was designed with VALVES, along with its
simpler version (without the two capacitors, called a bi-stable Multivibrator), it was
realised it …(circuits added 04/09) |
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Flip Flop Flashers Buzzers Etc - Several circuits here. The familiar astable
flip-flop circuit is a handy configuration for making flashers or generating
squarewaves. Here is a typical alternating LED flasher with the LEDs in the emitters
instead of collectors as is normally done. The bias resistors are directly
connected...(added 04/05/06) |
