2 Digit Digital Object Counter module and Infrared Transmitter


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48 In Stock

Regular price US$17.95
Delivery to USA, Canada, Australia, UK, Germany and Europe: 7-15 days
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This product is shipped from Sydney, Australia. Worldwide shipping available- we ship to USA, Canada, New Zealand, UK, EU, and Non-EU countries.

The new counter PCB will be in RED or WHITE Color.

This is one of the best sellers of BuildCircuit. We have sold more than 5000 copies in 45 countries. It is an excellent kit for beginners. Highly Recommended for beginners!

Description: A digital object counter can be used for counting objects. It can be used for fun at home for counting objects or people entering inside a room. Since it's a DIY kit, it can obviously be used for learning basic electronics.

This DIY digital object counter works with TSOP4838 infrared receiver and there are two seven segment displays displaying numbers from 0 to 99. An IR transmitter is oriented towards the TSOP4838 infrared receiver of the counter module and objects are moved between the two modules. Each time an object passes between the two modules, the seven-segment displays show increment in numbers.

Comes as a pack of parts kit and is easily assembled if you can follow the silkscreen indicators(labels) and have beginning experience with a soldering iron. You will need to read the resistor bands or use a multimeter to determine the resistor sizes.

Both the kits operate with 9V batteries.


The distance between the transmitter and receiver modules can be around 1 meter.

The counter module can be reset to 0 at any time and restart the counting.

The counter module can be operated with any kind of remote control. Therefore, it can also be used as a remote tester. For each press on the remote control, there is an increment in number.  

Kit package contains components for counter and IR transmitter modules:

A. Components for the counter module (altogether 26 components)

  • 1 x TO-92 5V Voltage Regulator(78L05)
  • 2 x CD4026 Decade counter
  • 2 x 16-pin IC socket.
  • 2 x common cathode seven segment display-(Can be in red, yellow and blue colors)
  • 1 x TSOP4838 Infrared sensor
  • 1 x 100uF Capacitor- (Voltage rating can be between 16V to 50V- causes no problem in operation)
  • 2 x 0.1uF 50V ceramic Capacitor
  • 2 x 3mm LED- (can be any color)
  • 1 x BC547
  • 1 x BC557
  • 1 x SPDT Slide Switch
  • 1 x Tactile reset switch
  • 1 x Screw terminal- (can be in blue/green colors)
  • 4 x 1K Ohm Resistor 1/4W
  • 1 x 330R Resistor 1/4W
  • 1 x 10K Ohm Resistor 1/4W
  • 1 x Bare PCB with Silkscreen Indicators- now in RED Color (udpated: 4.4.2016)
  • 1 x 9V battery connector

We may send 4 color or 5 color code resistors.

B. Components for IR transmitter module (altogether 12 components)

  • 1 x NE555 timer chip
  • 1 x 8-pin IC socket.
  • 1 x Infrared LED
  • 1 x 0.1uF 50Vceramic Capacitor - code 104
  • 1 x 0.001uF 50V ceramic Capacitor - code 102
  • 1 x SPDT Slide Switch
  • 1 x Screw terminal
  • 1 x 330R Resistor 1/4W
  • 1 x 10K Ohm Resistor 1/4W
  • 1 x 18K Ohm Resistor 1/4W 
  • 1 x Bare PCB with Silkscreen Indicators
  • 1 x 9V battery connector

We may send 4 color or 5 color code resistors.


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