Full Duplex Data transfer

[emrahdemirtekin]

I want to(or have to) design a simple circuit which enables two person to communicate within 10 meters. There must be only two wires between A and B terminals.We are just allowed to use simple electronic components(diodes,leds,transistors,resistance,battery and capacitors).Speed of data transfer is so important (speed means higher grades)

I designed a circuit (shown below) which depends on voltage change.By changing voltage i can change the number of flashing lamps.But i don't think that circuit is so suitable for my project because at max. voltage power across lamp 2 is about 18 watt which is 12 times greater than 1.5 Watt.Therfore lamp 2 is likely to fail.
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I want to get your valuable ideas.
Thanks for your consideration.

emrahdemirtekin@hotmail.com

 

[Papabravo]

Two straight keys with a current loop and morse code should do the job. Your scheme is needlessly complex and offers no discernable advantages. BTW the best telegraphers can do 40 to 60 words per minute.

 

[emrahdemirtekin]

But

a circuit with only two switches and two lampes doesn't offer a two way communication system.When A tries to send a signal ,the switch at B must be closed and vice versa.System must be ready for two way data transfer everytime.

 

[Pommie]

Use AC and put diodes across each switch and lamp so that one circuit works clockwise and the other anticlockwise.

Mike.
Edit, like this,

 

[emrahdemirtekin]

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This circuit can be used in only one direction at a time so it is not useful for me.
When both operators at the A and B terminals close switches neither of the LED s would turn on.
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That circuit is actually what i need but it uses 3 transmission lines between two terminals.Is there anyway to implement this system by 2 lines instead of 3 lines
by using mentioned simple electronic components?

 

[Pommie]

I added a circuit

 

[emrahdemirtekin]

I added a circuit

Unfortunately we are just allowed to use batteries hence i can't use AC power supply.


PROJECT CONSTRAINTS:

1.two wire between two terminals.
2.Allowed electronic components:transistors,diodes,capacitors,resistors,switches,LEDs or lamps
3.Batteries are the only power supplies.

Minumum electric power equals maximum grade.
Maximum data transfer rate equals maximum grade.
Anyway i am not a grade hunter.
I appreciate your help.

 

[Pommie]

Unfortunately we are just allowed to use batteries hence i can't use AC power supply.


PROJECT CONSTRAINTS:

1.two wire between two terminals.
2.Allowed electronic components:transistors,diodes,capacitors,resistors,switches
3.Batteries are the only power supplies.

Minumum electric power equals maximum grade.
Maximum data transfer rate equals maximum grade.
Anyway i am not a grade hunter.
I appreciate your help.

Use a bistable to generate the AC.

**broken link removed**

You would get a rough AC voltage between the 2 collectors.

Mike

 

[penoy_balut]

in your 4th post just reverse the polarity of the battery on second side, reverse the Led on first side, install the switches on battery positive side and add current limiting resistor on battery negative side because they are now in series connection.

 

[Hero999]

Use a bistable to generate the AC.

**broken link removed**

You would get a rough AC voltage between the 2 collectors.

That's an astable, and yes it will work but you need to add a push-pull emmitter follower stage with a DC blocking capacitor as a buffer to drive a significant load because it can't source much current.