555 trip alarm

ElectricSpidey

Joined Dec 2, 2017
3,335
You didn't say anything about a delay exit timer. :mad:

One more timer with the trigger hooked to a NO push button and an NPN transistor on the output with the collector hooked to the net marked "RESET".

I already asked the question about what "pulse" meant early in this thread and didn't get an answer. (well, an obscure one)

If you need an on/off/on/off output, then the suggestion I made early in the thread will do it.

2 556s give you a delayed entry and exit and a "pulsed" output. 3 monostable and one astable. but another inversion is needed.
 
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Thread Starter

liteace

Joined Mar 7, 2012
242
You didn't say anything about a delay exit timer. :mad:

One more timer with the trigger hooked to a NO push button and an NPN transistor on the output with the collector hooked to the net marked "RESET".

I already asked the question about what "pulse" meant early in this thread and didn't get an answer.
Sorry Ive got a million things in my head + Im old so most of them get forgotten,

I just assumed as it was delay entry it'd be delay exit but life's not that simple.

yes need pulsed out relay control and entry+ exit delay as my plan is to put the arm / disarm no where near the door so if someone does walk in with me they cant see the combination (if combination keypad used) or location of key switch
 

sghioto

Joined Dec 31, 2017
8,634
Here's my version using four NE555s.
The unit is armed and disarmed by the Sw2.
When first armed IC1 starts a 10 second delay inhibiting IC2 which is a 40 second timer allowing time to exit.
After the 10 second delay has expired and the trip switch Sw1 is closed it starts the 40 second timer.
IC4 is the pulser circuit for the relay but it is deactivated by R7.
When the 40 second timer starts it also starts IC3 which is another 10 second timer providing an entry delay.
After the entry delay has expired the relay will start pulsing for the remaining 30 seconds of the 40 second timer.
1719968265837.png
 
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Thread Starter

liteace

Joined Mar 7, 2012
242
After the entry delay has expired the relay will start pulsing for the remaining 30 seconds of the 40 second timer.
After the 30 seconds has elapsed it'll reset itself ready for the next trigger?
can this be run from 12v instead of 5v? if not no probs as I can add a regulator
Is there anyway of adding trigger delay buzzer, something thats sounding before main alarm fires up

Thanks
 

sghioto

Joined Dec 31, 2017
8,634
After the 30 seconds has elapsed it'll reset itself ready for the next trigger?
can this be run from 12v instead of 5v? if not no probs as I can add a regulator
Is there anyway of adding trigger delay buzzer, something thats sounding before main alarm fires up
Thanks
It will reset but will not trigger again unless the door has been closed
12 volts is fine.
Buzzer can be added, I forgot about that feature will add in soon.
 

sghioto

Joined Dec 31, 2017
8,634
Yes please could you add that
How much current does the horn, siren and strobe require?
Asking to determine what type of relay would be adequate.
Technically a relay could be connected directly to pin3 of IC3 to drive the siren and strobe.
 
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Thread Starter

liteace

Joined Mar 7, 2012
242
When first armed IC1 starts a 10 second delay inhibiting IC2 which is a 40 second timer allowing time to exit.
After the 10 second delay has expired and the trip switch Sw1 is closed it starts the 40 second timer.
IC4 is the pulser circuit for the relay but it is deactivated by R7.
When the 40 second timer starts it also starts IC3 which is another 10 second timer providing an entry delay.
After the entry delay has expired the relay will start pulsing for the remaining 30 seconds of the 40 second timer.
Sorry for all the questions and being dumb, Im not getting:

"After the 10 second delay has expired and the trip switch Sw1 is closed it starts the 40 second timer"

Is this entry or exit?
 

Thread Starter

liteace

Joined Mar 7, 2012
242
Ive ordered a 110x93mm strip board, will this all fit on and is there any programs I can use that will help me with component layout on a strip boad, would like to build a PCB like back in the old days but dont have the hardware

Thanks
 

sghioto

Joined Dec 31, 2017
8,634
Ive ordered a 110x93mm strip board, will this all fit on and is there any programs I can use that will help me with component layout on a strip boad, would like to build a PCB like back in the old days but dont have the hardware
Thanks
That board should be large enough. There are programs out there and YouTube tutorials. Search "stripboard layout software". Never used any so can't recommend anything.
 
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