I don't have a IRF540 on hand but the circuit worked just fine using a IRF520 mosfet. IRF540 has same gate threshold as the IRF520 so should work. Which circuit did you try?
The correct version is below.

 

I don't have a IRF540 on hand but the circuit worked just fine using a IRF520 mosfet. IRF540 has same gate threshold as the IRF520 so should work. Which circuit did you try?
The correct version is below.
View attachment 228285

yes. I tried the same circuit. R1, R5 and C1 are different but that's for delay and LED. should not matter.

 

Does the monostable time out after one press of the button?

 

Does the monostable time out after one press of the button?

first press - led on (stays on for 16 seconds as set by RC circuit - R1,C1)
second press - nothing happens until the led is off.

 

OK must not be connected correctly.
If you can post a HD closeup of the breadboard I might be able to see why it's not working.

 

OK must not be connected correctly.
If you can post a HD closeup of the breadboard I might be able to see why it's not working.

sure. I will send it tomorrow morning.

 

sure. I will send it tomorrow morning. The circuit is in office

 

Nicer version using one transistor.
Works in your Simulator.

 

Nicer version using one transistor.
Works in your Simulator.

View attachment 228330

ohh nice.. thank you for the effort

 

Nicer version using one transistor.
Works in your Simulator.

View attachment 228330

Can you share your design that you used in simulation?? I made this design and it doesn't work. Nothing happens when I press the button. LED not even switching. convenient thing would be if you can 'save as' your simulation and share link.

edit : it works. I forgot to attach battery sorry. thanks again
Thanks and Regards