Naked Science Forum

Non Life Sciences => Technology => Topic started by: Cody on 20/01/2011 03:30:04

Title: How does the game operation work?
Post by: Cody on 20/01/2011 03:30:04
Cody asked the Naked Scientists:
   
how does the game "Operation" work?

Cody

What do you think?
Title: How does the game operation work?
Post by: Daerana on 25/01/2011 02:40:06
Basically, the game works by creating a simple circuit.  The battery, light, buzzer, metal edges on the body and metal tweezers are connected by wires yet the wires do not go in a full circle.  ie. imagine that each part is like on a chain yet it wont work unless the chain is done up and goes in a full circle.  This is called a complete circuit.  To complete the circuit the metal of the tweezers must touch the metal edge of the body.  This connection works the same as a switch would in a simple circuit such as turning on a light.  When the circuit is complete the light and buzzer turn on from the power in the battery.  However, if the circuit is not complete this can't happen.

Hope this helps.
Title: How does the game operation work?
Post by: RD on 25/01/2011 07:06:05
To complete the circuit the metal of the tweezers must touch the metal edge of the body. 
 This connection works the same as a switch would in a simple circuit such as turning on a light.

It's a long time since I played operation, but isn't there a latch circuit (http://en.wikipedia.org/wiki/Latch_%28electronics%29) involved:
 even though the metal-metal connection may only be made momentarily the buzzer and light stay on until reset.
 
I may be wrong, like I said it's been a long time.
Title: How does the game operation work?
Post by: Geezer on 25/01/2011 07:29:34
I think you are right. Here's a simpler version - 

[diagram=620_0]
Title: How does the game operation work?
Post by: RD on 25/01/2011 08:03:31
A couple of 555 timer (http://en.wikipedia.org/wiki/555_timer) circuits would do it : one to make a latch (http://www.kpsec.freeuk.com/555timer.htm#bistable) and  one to make a buzzer (http://www.kpsec.freeuk.com/555timer.htm#astable).


Title: How does the game operation work?
Post by: Geezer on 25/01/2011 18:07:22
My "drawing" is a latch
Title: How does the game operation work?
Post by: RD on 25/01/2011 23:28:45
My "drawing" is a latch

The block diagram symbol for a latch is a rectangle: here is the RS latch in the 555 timer IC (http://en.wikipedia.org/wiki/555_timer) (coloured) ...

 [ Invalid Attachment ]  (http://en.wikipedia.org/wiki/File:NE555_Bloc_Diagram.svg)


More (rectangular) latch symbols here ... http://en.wikipedia.org/wiki/Flip-flop_%28electronics%29#Implementation
Title: How does the game operation work?
Post by: Bored chemist on 26/01/2011 06:55:35
Geezer's diagram, while spectacularly unclear, is a latch.
Perhaps more importantly, I think that game might have been going longer than the 555.
If so, I wonder what the original electronics were.
Title: How does the game operation work?
Post by: RD on 26/01/2011 07:07:49
I wonder what the original electronics were.

Could be made with a pair of transistors ... http://en.wikipedia.org/wiki/File:Flipflop_by_trexer.png
Title: How does the game operation work?
Post by: Geezer on 26/01/2011 21:22:08
Pretty much anything with more than unity gain could be used. That might be a couple of transistors, a relay, or a non-inverting logic buffer.

However, I have a vague recollection that the buzzer sounded for a bit, then shut itself off. If that's true, then a latch won't quite hack it. We'll need a monostable of some sort. That could be done with some sort of resistor/capacitor network to produce a time constant, combined with a couple of transistors, a relay, or a non-inverting logic buffer.

As relays tend to be a lot more expensive than transistors, I'd think it's most likely they used a couple of cheap transistors.
Title: How does the game operation work?
Post by: Geezer on 27/01/2011 07:47:56
With lots more detail.

 [ Invalid Attachment ]