Switched ON Bike Lamp circuit diagram:

Component part list:

This switched ON bike lamp circuit was primarily intended to permit automatic switch-on of push-bike lights when it gets dark. Naturally, it might be applied for any other purpose involving one or more lamps to be switched on and off depending of light intensity. Power could be supplied by any kind of battery suitable to be fitted in your bike and having a voltage within the 3 to 6 Volts range. The Photo resistor R1 needs to be fitted into the box containing the total circuit, but a hole should be created in a convenient side of the box to allow the light hitting the sensor. Trim R2 until the desired switching threshold is reached. The setup will require some experimenting, but it ought to not be hard.

Bike Lamp circuit notes:

• In this circuit, the maximum electric current and voltage delivered to the lamp(s) are limited primarily by R6 (that can’t be omitted if a clean and reliable switching is expected). Consequently, the Ohm’s Law should be applied to calculate the ideal voltage and current values of the bulbs.
• At 3V supply, R6 value may be lowered to 1 or 0.five Ohm and the operating voltage of the bulbs should be chosen accordingly, by applying the Ohm’s Law. Example: Supply voltage = 3V, R6 = 1R, total current drawing 600mA. Decide on 2.2V bulbs as the voltage drop caused by R6 will probably be 0.6V.
• At 3V supply, R5 value should be changed to 100R.
• As an example: at 6V supply, one or much more 6V bulbs having a total current drawing of 500mA can be applied, but for a total current drawing of 1A, 4.5V bulbs need to be chosen, as the voltage drop across R6 will become 1.5V. In this case, R6 should be a 2W type.
• Stand-by current is much less than 500uA, provided R2 value following trimming is set at about 5K or greater: for that reason, the power switch SW1 could be omitted. If R2 value is set below 5K the stand-by current will enhance substantially.

Switched ON Bike Lamp circuit source: redcircuit.com

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When the gate and the source are connected together, it acts as a current regulator.

In the circuit above, the current is constant between 6 and 8 mA at 5 to 30Vdc. If the diode is added (the 1N4148 is optional), this circuit is secured agains polarity reversal and can be connected to a AC power supply of 5 to 20 VAC.

LED Pilot Light using FET, circuit designed by Tony Van Roon

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Here the simple traffic light controller which is could be used to educate kids rudiments of traffic light guidelines. The circuit utilizes easily available electronic parts. It generally consists of rectifier diodes (1N4001), a 5V regulator 7805, two timers circuit using IC 555, two relays (5V, single-changeover), three 15W, 230V light bulbs and also several discrete parts.

Mains electrical power is stepped down by transformer X1 to provide a secondary output voltage of 9V, 300 mA – AC. Then the transformer output current is rectified by a full-wave bridge rectifier composed of diodes D1 through D4, filtered by capacitor C1 and also regulated by IC 7805 (IC1).

IC2 is wired as a multivibrator with ‘on’ and ‘off’ periods of about 30 seconds each with the part values determined. Once mains power switch is turned on, pin 3 of IC2 goes high for 30 seconds. This, in turn, energises relay RL1 via transistor T1 and the red bulb (B1) glows through its normally-open (N/O) contact. At the same time, mains power is turned off from the pole of relay RL2.

As the ‘on’ time of IC2 ends, a triggers IC3 through C5. IC3 is set up as a monostable with ‘on’ time of about 4 seconds, which indicates pin 3 of IC3 will stay high for this period of time and energise relay RL2 through driver transistor T2. The amber bulb (B2) thus lightings up for 4 seconds.

Immediately after 4-second time period of timer IC3 at pin 3 lapses, relay RL2 de-energises and also the green bulb (B3) lights up for the rest of ‘off’ period of IC2, which is about 26 seconds. The green bulb is turned on through the normally closed (N/C) contacts of relay RL2.

So when mains electrical switch is turned on, red light will light up for 30 seconds, amber for 4 seconds and green for 26 seconds.

You can easily build this circuit on a general purpose PCB and enclose in a protected box. The box needs to have sufficient area for installing transformer X1 and also two relays. It could be installed near 230V AC, 50Hz power supply or mounted on the PVC tube applied in assembly of the traffic light box.

Design of the traffic light container box is demonstrated in following image:

A stout cardboard box of 30x15x10cm3 is needed for housing the lights. To make certain durability, work with a 10x45cm2 plywood plate having 1.5 centimeters thickness and also secure onto it three light outlets and the box utilizing nuts and bolts or screws.

Make three tubes of thin aluminium sheet, which is easily offered in equipment stores. The inner diameter of aluminium tubes ought to be such that these can well match on the light outlets. Working with a sharp knife, make holes opposite the outlets carefully. Wire the outlets at the back and take the cables out through the PVC tube.

To begin with, fix three 15W light bulbs (B1 through B3) and then press on the tubes. Support the other ends of the tubes in the holes made on the front panel of cardboard box. Sandwich gelatine papers of the three colors in between two sheets of cardboard and fix over the tubes. The visibility of red, amber and also green lights enhances with their installation on the tubular shape.

Simple traffic light controller circuit diagram

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The work of this circuit is simple. The 400V capacitor, the bridge rectifier, the zener diode and the capacitor 100uF will form the power supply voltage which obtained approx. 9VDC from transformerless power supply design. The integrated 555 and its annexes components generate a train of pulses applied on the triac optocoupler MOC3021 driven intermittently causing the lamp on and off continuously. The triac may be a 2N6073A or TIC226D. By changing the 100K resistor or 1uF capacitor, then the flashing time will changed too. The rectifier bridge may be four 1N4007 diodes or 400v bridge diode with 1A current. The triac should be mounted on a heat sink to prevent over heating.

Warning!!! The entire circuit operates from 220v mains without insulation so the appropriate safety precautions should be taken to minimize the risk. Build this 220V 800W lamp flasher circuit with your own risk.

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Component Lists:

How the circuit work:
Due to the low current drawing, the circuit can be supplied from 220Vac mains without a transformer. Supply voltage is reduced to 10Vdc by means of C1 reactance, a two diode rectifier cell D1 & D2 and Zener diode D3. IC1 is a CMos 555 timer wired as a monostable, providing 15 seconds on-time set by R3 & C4. When SW1 is closed, IC1 output (pin 3) is permanently on, driving Triac D4 which in turn feeds the lamp. Opening SW1 operates the monostable and, after 15 seconds, pin 3 of IC1 goes low switching off the lamp.

Notes:

• The circuit is wired permanently to the mains supply but current drain is negligible.
• Due to transformerless design there is no heat generation.
• The delay time can be varied changing R3 and/or C4 values.
• Taking C4=10uF, R3 increases timing with approx. 100K per second ratio. I.e. R3=1M Time=10 seconds, R3=1M8 Time=18 seconds.
• Low Gate-current Triacs are recommended.
• Use a well insulated mains-type switch for SW1.

WARNING!!! This circuit using high voltage source. Please Make sure you use a safety device before trying to activate this circuit.

Source: redcircuit.com

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This is the electronic bicycle directional lights circuit that use inexpensive components and is a good substitute to many commercially available versions in the marketplace. This circuit works in an extremely different manner and is convenient to operate.

The bicycle direction indicators circuit works off a 9V PP3 (alkaline-type) battery and is basically a set of two independent free-running oscillators (astable multivibrators) built around four low-power transistors and a few passive components. Both the square-wave oscillators (one built around T1 and T2 and the other built around T3 and T4) drive four red LEDs (LED1 and LED2, and LED5 and LED6, respectively), which blink to indicate the direction of turn. Additional steady-glow LEDs (LED3 and LED4) are incorporated to indicate the working status.

How the Bicycle Directional Signal Lights Works

When switch S1 is flipped to “on” position, DC supply from the battery is extended to the oscillator circuit formed by transistors T1 and T2. Now the left-side oscillator starts oscillating and the visual indicators at the front left (FL) and rear left (RL) start blinking at a rate determined by timing capacitors C1 and C2. Resistors R2 and R3 limit the operating current of LEDs (LED1 and LED2). At the same time, the green LED (LED3) starts glowing to indicate the present direction status.

Similar action happens in the next oscillator circuit built around transistors T3 and T4 when switch S2 is flipped to “on” position. Indicators at the front right (FR) and rear right (RR) start blinking, and at the same time the green LED (LED4) glows to indicate the direction status.

Switch S3 is used for emergency indication. When it is flipped to “on” position, both the oscillators get power supply through diodes D1 and D2. As a result, LED1 through LED6 start working simultaneously. In this condition, all the LEDs blink, except LED3 and LED4, which glow steadily.

Bicycle Directional Lights Assembly

After assembling the circuit on a general purpose PCB, enclose it in a suitable cabinet as shown the following image and mount on the handle bar of the bicycle, preferably at the mechanical centre point.

Connect switch S1 at the left-hand side, S2 at the right-hand side and emergency switch S3 in the middle of the master unit. Now place this master unit at the top of the handle bar and do the essential interconnections using flexible wires. Connect the front indicators (LED1 and LED5) to the left and right side of the handle and similarly rear indicators (LED2 and LED6) can be mounted in the carrier frame of the bicycle.

For the direction indicator, you can use the direction symbol and place it at the centre of the handle, look at above image for reference.

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There are two circuit modes: dimming and flashing. The flasher mode is useful for warning other drivers of your troubles and it may be adjusted to have a very short flash duration for long-term use as when the car must be left on the shoulder over night.

Electronic Parts List:

Lantern Dimmer Circuit Notes:

• S1 switch is used to activate the ‘Flashing’ mode.
• P1 is the dimmer potentiometer, you can adjust the dimming setting from here.
• Transistor 2N4401 can be substituted with a NTE123AP, the BC547.
• Transistor TIP32 can be substituted with a NTE197. Other transistor types might be work.
• The DC power supply or battery for this lantern dimmer / flasher is 6-12V.

There is nothing particularly critical about the resistor and capacitor values and the experimenter may change them, if desired. For example, a 10K-pot may be substituted for the 5K by increasing the 3.9K resistors by 2 also (8.2K would be fine). The 100K’s in the flash circuit may be a different value if the capacitors are also scaled (inversely–if the resistors are doubled, the 0.1 and 10uF are halved).

Good luck…

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The game is simple. As stated above, it is a scoring game and the competitor who scores 100 points rapidly (in short steps) is the winner. For scoring, one has the option of pressing either switch S2 or S3. Switch S2, when pressed, makes the counter count in the forward direction, while switch S3 helps to count downwards.

Before starting a fresh game, and for that matter even a fresh move, you must press switch S1 to reset the ci cuit. Thereafter, press any of the two switches, i.e. S2 or S3.

On pressing switch S2 or S3, the counter”s BCD outputs change very rapidly and when you release the switch, the last number remains latched at the output of IC2. The latched BCD number is input to BCD to 7-segment decoder/driver IC3 which drives a common anode display DIS1. However, you can read this number only when you press switch S4.

The sequence of operations for playing the game between, say two players “X” and “Y”, is summarised below:

1. Player “X” starts by momentary pressing of reset switch S1 followed by pressing and releasing of either switch S2 or S3. Thereafter he presses switch S4 to read the display (score) and notes down this number (say X1) manually.
2. Player “Y” also starts by momentary pressing of switch S1 followed by pressing of switch S2 or S3 and then notes down his score (say Y1), after pressing switch S4, exactly in the same fashion as done by the first player.
3. Player “X” again presses switch S1 and repeats the steps shown in step 1 above and notes down his new score (say, X2). He adds up this score to his previous score. The same procedure is repeated by player “Y” in his turn.
4. The game carries on until the score attained by one of the two players totals up to or exceeds 100, to be declared as the winner.

Several players can participate in this game, with each getting a chance to score during his own turn.

Construct the circuit using a multipurpose PCB. Fix the display (LEDs and 7-segment display) on top of the cabinet along with the three switches. The supply voltage for the? circuit is 5V. You may use three batteries with series connection to operate this game scoring display circuit.

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and the result should be like this:

Replace the Resistor 10K with variable resistor 20K or replace the electrolytic capacitor 100uF with other value for change the frequency of LED’s flash.

Flip flop PCB layout:

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1. The first part consists of? IC1 (555), IC2 (74LS164), IC3 (74LS86), IC4 (74LS00) and the associated pars. These generate a randomly changing train of pulses.
2. The second part of the circuit?comprises SCR1 (C106), an electric bulb connected between anode of SCR1 and mains live wire, and gate trigger circuit components. It is basically half-wave AC power being supplied to the electric bulb.
3. The third part is the power supply adapter circuit to produce regulated 5V DC from 230V AC for random signal generator. It comprises a stepdown transformer (X1), full-wave rectifier (diodes D3 and D4), filter capacitor (C9), followed by a regulator (IC5).

The random signal generator of the circuit is built around an 8-bit serial in/parallel out shift register (IC2). Different outputs of the shift register IC pass through a set of logic gates (N1 through N5) and final output appearing at pin 6 of gate N5 is fed back to the inputs of pins 1 and 2 of IC2. The clock signal appears at pin 8 of IC2, which is clocked by an astable multivibrator configured around timer (IC1). The clock frequency can be set using preset VR1 and VR2. It can be set around 100 Hz to provide better flickering effect in the bulb.

The random signal triggers the gate of SCR1. The electric bulb gets AC power only for the period for which SCR1 is fired. SCR1 is fired only during the positive half cycles. Conduction of SCR1 depends upon the gate triggering pin 3 of IC2, which is random. Thus, we see a flickering effect in the light output.

Assemble the circuit on a generalpurpose PCB and enclose it in a suitable case. Fix bulb and neon bulb on the front side of the cabinet. Also, connect a power cable for giving AC mains supply to the circuit for operation. The circuit is ready to use.

Be careful since this circuit uses home electrical installation? 220V AC voltage.

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