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| 333 sales | 5 out of 5 stars 26 reviews

Choccy Block / Terminal Strip Alternate Flashing Light Flip-Flop Kit of Electronic Parts 5060971140025



In stock

Local taxes included (where applicable), plus postage

  • Handmade
  • Dispatches from a small business in

    United Kingdom

  • Materials: Electronic Parts, Transistor, LED, Resistor, Capacitor

This is a kit of electronic parts for a transistor light flashing circuit which alternately flashes two sets of LEDs or lamps. It is built entirely without soldering using a 12-way 3A terminal strip. This is somewhat better than the simpler versions available elsewhere, in that it has two additional output driver transistors. This allows you to flash more than two little LEDs, or use proper lamps.

All the build information is provided online so that easy updates can be added. The build information is full and detailed, and there's a full electronic explanation provided with oscilloscope screen-shots. Three different resistor values are provided for different flashing rates. If you're looking for a school science project which you can knock-up in a hurry, then look no further.

The fully detailed instructions are available here:


This is the Bill Of Materials:

Flashing Light Flip-Flop 1 Bill Of Materials

Electronic Parts Included in the Kit

Qty Refs Type Value

2 R1,R2 Resistor 4.7K 0.5W
2 R3,R4 Resistor 68K 0.5W, alt values 47K and 100K
2 R5,R6 Resistor 470R 0.5W
2 C1,C2 Capacitor 10uF NP
2 Q1,Q2 Transistor BC549C
2 Q3,Q4 Transistor BD140-16


1 12-way 3A Terminal Strip
1 4 X AA Battery Holder
2 2 X M.E.S. lampholder
2 2 X 6V 0.1A lamps
1 D1 red wired LED with resistor
1 D2 green wired LED with resistor
0.5 100mm black single core wire
1 100mm red single core wire
4 100mm orange single core wire

In addition you will need four AA batteries, a small screwdriver, some wire cutters, small pliers, and some means of stripping the insulation from the wire in addition to the above.

EAN 5060971140025


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29 Jun.-01 Jul.

25 Jun.

After you place your order, UsefulComponents will take 1 business day to prepare it for dispatch.

27 Jun.

UsefulComponents puts your order in the post.

29 Jun.-01 Jul.

Estimated to arrive at your doorstep 29 Jun.-01 Jul.!

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Etsy offsets carbon emissions from delivery and packaging on this purchase.
Etsy offsets carbon emissions from delivery and packaging on this purchase.

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Dispatches from United Kingdom

Henry Walmsley

Henry Walmsley

Owner of UsefulComponents

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VAT ID GB318381695

26 shop reviews

5 out of 5 stars
5 out of 5 stars

quality very good, back in time. I was 12 years old now I am 82 , wonderful that it is still for sale. toppie toppie growth se

matt 03 Jan, 2022

5 out of 5 stars

wonderful Etsy Seller, provided excellent after sales support. The kit itself was beautifully packaged and we were excited to put together. thank you.

Daniel 26 Feb, 2022

5 out of 5 stars

Great activity with the child, perfect service and delivery

ThistleBeth 10 Feb, 2022

2 out of 5 stars

one item missing no assembly instructions

tony williams 15 Jun, 2022

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