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For school I have to build a astable circuit that stays on for 5 seconds and then turns off for 1 second. However my circuit isn't working I am do not know why here is my circuit on a bread board. The led stays on but never turns off.

The schematic can be found here for the output I added 1000ohms resitor. R1=680kohms and R2=145kohms

Bread board circuit

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    \$\begingroup\$ What is the chip? Where is the schematic? Without this information we cannot help you. \$\endgroup\$
    – Willy Wonka
    Commented Mar 12, 2019 at 14:51
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    \$\begingroup\$ You need to add a schematic, otherwise we are unable to say anything useful. \$\endgroup\$
    – Colin
    Commented Mar 12, 2019 at 14:51
  • \$\begingroup\$ I have added the schematic sorry for the mistake. \$\endgroup\$
    – J.C
    Commented Mar 12, 2019 at 14:56
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    \$\begingroup\$ Your capacitor looks way too small to give you a period in seconds. What size is it? \$\endgroup\$
    – HandyHowie
    Commented Mar 12, 2019 at 15:01
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    \$\begingroup\$ Using the calculator on the page you provided, you get a frequency of 148Hz with a 10nF capacitor. Try something like a 10uF or 100uF to see what happens. \$\endgroup\$
    – HandyHowie
    Commented Mar 12, 2019 at 15:04

1 Answer 1

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You have pin 2 connected to ground and pin 1 floating. Move the black ground jumper from pin 2 to pin 1. Because of this error, the 555 might have been damaged. You should replace it after you correct the circuit.

The capacitor at pin 6 is 10 nF. Increase this to 10 uF.

Recalculate R1.

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