Based on the page you have landed on, we have selected the Education website as your default.

If you would like to change your default sector, click the Change Product Range link above the Rapid logo.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we'll assume that you are happy to receive all cookies on the Rapid website. However, if you would like to, you can change your cookie settings at any time.


555 Astable projects

This project has been designed to introduce the important concept of astable timers and pulse-width modulation using the 555 timer astable circuit.

Comprehensive teacher notes are available here.

This circuit is very important as it features heavily in KS4 curriculums. It has been designed to have more than one possible outcome and therefore more than one application. It allows for good differentiation and includes a transistor drive circuit.

  • Frequency can be varied by the 2 variable resistors
  • Battery-powered
  • PCB has space for a transistor drive circuit to allow higher powered outputs to be added
  • Clear silkscreen text has been used to make construction simpler
  • Professional double-sided PCB pre-drilled with silkscreen and solder-resist
  • 3 versions available for maximum flexibility: see technical specification
  • Empty PCBs are available separately, order code 70-9036
  • Suitable for Key Stages 2, 3 & 4 (ages 11 to 16)

Project notes for this and other project kits are available for download at our Education Resources site.
Product details Hints & Tips






Manufacturer’s Part Number: KIT

555 Astable Project - Economy


In stock, despatched same day

Manufacturer’s Part Number: KIT

555 Astable Project - with Drive Circuit


In stock, despatched same day

Manufacturer’s Part Number: KIT

555 Astable Project - Deluxe


In stock, despatched same day

Manufacturer’s Part Number: 70-6017A

555 Astable Projects (70-6017/8/9) Pcb


In stock, despatched same day

Technical Specification

  Only part of this technical specification is being displayed.
Click here to expand

Parts and quantities per kit
Order codeDescriptionEconomyWith drive circuitDeluxe
08-0275100nF ceramic capacitor1
11-022010uF electrolytic capacitor111
18-0092Battery clip PP3111
21-04612–way 16A 5mm terminal block2
22-01198–pin DIL socket111
47-31421N4007 1A diode11
55-17905mm red LED111
55-17925mm green LED111
62-03140R resistor222
62-0359270R resistor222
62-03731K resistor11
67-04082K preset222
76-0302SPDT slide switch111
81-0122BFY51 NPN transistor11
82-0336NE555 timer111


Be the first to ask a question


One Star (Filled)One Star (Filled)One Star (Filled)One Star (Filled)One Star (Empty) Diagrams needed? Diagrams ARE Provided
Reviewed by: GJ
1st January 2012

For anyone reading the above review, please ignore it. There are copious teachers notes provided via PDF which can be viewed before you buy. If anything, there are too many notes/diagrams as it leaves the students nothing to do, the idea is the teacher decides what information to give out depending on what level of students are being taught.

One Star (Filled)One Star (Filled)One Star (Filled)One Star (Empty)One Star (Empty) Middle of the road kit
Reviewed by: KB | Product code: 70-6019
27th September 2011

Easy to build. One problem though, there are five resistors in this kit.. The students will drive you mad asking which resistor goes where. Although a simple kit; a diagram would be nice.

< Electronics Kits

Electronic Project Kits