Switched ON Bike Lamp

Do you have a bicycle..? why don’t try to build this circuit..?. Powered using battery 3-6V. This circuit will help the bicycle driver in the night and help other people to know your presence.

Switched ON Bike Lamp circuit diagram:

Component part list:

R1 = Photo resistor (any type)
R2 = 22K 1/2W Trimmer Cermet or Carbon type
R3 = 1K
R4 = 2K7
R5 = 330R *
R6 = 1R5 *
D1 = 1N4148Q1 = BC547
Q2 = BD438
LP1 = Filament Lamp(s) *
SW1 = SPST Toggle or Slider Switch
B1 = 6V or 3V Battery *

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

circuit diagram

Share
Published by
circuit diagram

Recent Posts

Guitar Synthesizer Schematic Diagram Collection

Guitar Synthesizer Schematic Diagram In this post, we provide a collection of schematic diagrams of…

54 years ago

Handy Talky HT DIY Schematic Diagram

Handy Talky Schematic Diagram This is an old electronic scheme of the Handy Talky (HT)…

54 years ago

Doorbell Ringer Birdie Tone

This is an old or "very old" schematic diagram of birdie tone or sound generator.…

54 years ago

200W MOSFET Amplifier based IRFP250N

Here is the 200W MOSFET amplifier powered based on four piece of IRFP250N, they are…

54 years ago

300W RMS Stereo Power Amplifier based IC TDA7294

This is the 300W RMS stereo power amplifier circuit project. This amplifier is based four…

54 years ago

Stereo Tone Control with Line In + Microphone Mixer

This is an active stereo tone control circuit using very well known op-amp IC of…

54 years ago