Description.
The circuit shown here is of a simple 0 to 9 display that can be
employed in a lot of applications. The circuit is based on asynchronous
decade counter 7490(IC2), a 7 segment display (D1), and a seven segment
decoder/driver IC 7446 (IC1).
The seven segment display consists of 7 LE
Featured Post Today
Description. The circuit shown here is of a simple 0 to 9 display that can be employed in a lot of applications. The circuit is based on asynchron...
Read more »
Latest Post
Multitasking Pins Circuit
Circuit Diagram
Description
It’s entirely logical that low-cost miniature microcontrollers have
fewer ‘legs’ than their bigger brothers and sisters – some-times too
few. The author has given some consideration to how to economise on
pins, making them do the work of several. It occurred that
Brightness Controller Circuit For Small Lamps and Leds
Description
This device was designed on request; to control the light intensity
of four filament lamps (i.e. a ring illuminator) powered by two AA or
AAA batteries, for close-up pictures with a digital camera. Obviously it
can be used in other ways, at anyone's will.IC1 generates a
On-off Infrared Remote Control Circuit
Description
Most homes today have at least a few infrared remote controls,
whether they be for the television, the video recorder, the stereo, etc.
Despite that fact, who among us has not cursed the light that remained
lit after we just sat down in a comfortable chair to watch a good fil
Monostable Flip Flop Circuit
Description
The monostable flip flop, sometimes called a 'one shot' is used to
produce a single pulse each time it is triggered. It can be used to
debounce a mechanical switch so that only one rising and one falling
edge occurs for each switch closure, or to produce a delay for timing
a
Hearing Aid Circuit
Description
Commercially available hearing aids are quite costly. Here is an
inexpensive hearing aid circuit that uses just four transistors and a
few passive components.
Circuit Diagram
Parts:
R1 = 2.2K
R2 = 680K
R3 = 3.3k
R4 = 220K
R5 = 1.5K
R6 = 220R
R7 = 100K
R
Fog Lamp Switch Circuit
Description
In most countries it is now mandatory or at least recommended to have a
rear fog light on a trailer with the additional requirement that, when
the trailer is coupled to the car, the rear fog light of the towing car
has to be off. The circuit shown here is eminently suitable f
Car-Bulb Flasher Circuit
Description
This astonishingly simple circuit allows one or two powerful 12V 21W car
bulbs to be driven in flashing mode by means of a power MosFet. Devices
of this kind are particularly suited for road, traffic and yard alerts
and in all cases where mains supply are not available but a
Ignition Coil Buzz Box Circuit
Description
Here's a circuit to create a buzzcoil using a standard automotive
ignition coil. A 556 dual timer is used to establish the frequency and
duty cycle of the coil current. One of the timers is used as an
oscillator to generate the 200 Hz rectangular waveform needed to control
t
Line Powered White LEDs
Description
The LED circuit below is an example of using 25 white LEDs in series
connected to the 120VAC line. It can be modified for more or less LEDs
by adjusting the resistor value. The exact resistance will depend on the
particular LEDs used. But working out the resistor value is a b
