Game Buzzer Circuit

Thread Starter

QuangVuong

Joined Apr 2, 2011
12
Hi
I'm kinda new to making circuits. I have a monostable 555 timer circuit which I need to integrate with another one. So if S1(PTM) is pressed thelight will stay on for about 5 seconds and the other switch cannot be used when the other switch is on. Vice versa.

So I have drawn up a circuit in Yenka, and everything works. Except the light stays on forever. I tried increasing the resistance and lowering the capacitance but the light will not turn off after a few seconds. Would anyone have an idea? To turn the light off after a few seconds. If anyone wants to have a look at the circuit, I'll upload it.

Its the bottom circuit.
 

Attachments

Last edited:

Wendy

Joined Mar 24, 2008
23,421
Schematic please. Schematics tell much more than words.

Have you thought of using the output of each 555 to feed the reset line of the others?
 

KMoffett

Joined Dec 19, 2007
2,918
Never seen YENKA. Please post your image in a .png, .jpg, .gif, .pdf, or .doc file format so we can see it.

Ken
 
Last edited:

Wendy

Joined Mar 24, 2008
23,421
I was about to make the same comment. I haven't even heard of it, which is unusual. The best graphic format is .png, or .gif .
 

Thread Starter

QuangVuong

Joined Apr 2, 2011
12
Yenka is a program which helps us draw up circuit diagrams and test them. It's a free program.

Anyway, I'll take a screenshot and upload it here.
 

Thread Starter

QuangVuong

Joined Apr 2, 2011
12
Which inverter should I be using? 324op amp or 741 op amp?

I need to use the basic monostable design to make a buzzer system, where a light turns on when one of the PTM switches are pressed. The light will turn off shortly. Anyone can press their switch, but only one light can stay on at a time. There will only be two switches.

Im also thinking of using a thyristor, but then I need to find a way to connect the monostable circuit to a thyristor and then have two connected together. I can do it with a LED, but am having trouble with connecting the monostable circuit to the thyristor. Does anyone have an idea?

Or how to just make a circuit which works like game shows on TV, but it has to use a monostable design?
 
Last edited:

Wendy

Joined Mar 24, 2008
23,421
How about a CMOS (digital logic) inverter? You can also use 2 resistors and a transistor to make a single inverter (any general purpose NPN and two 10KΩ resistors).

You didn't name inverters, you named op amps.

Classic CMOS Hex inverters (6 in a package) would include a 4049, 4069, 40098, 40106. TTL is limited in voltage but examples would be the 7404, 7414.

A good chip reference (there are many) is Sams Electronics Circuits (no relation to Sams).

http://users.otenet.gr/~athsam/database.htm

With any chip, be it digital or analog, ground the inputs to unused gates or op amps.
 

Thread Starter

QuangVuong

Joined Apr 2, 2011
12
Yeah, I used a different method. I used 2 relays to spilt the circuits. When current passes through one, the relay will cut off the other one. Thanks for all your help
 
Top