512hz transmitter

Thread Starter

Guitar713

Joined Jul 20, 2021
2
Im making a circuit with a 555 timer to transmit 512hz through the air. Right now it only travels inches... how can I get the signal to travel a few meters?
 

Danko

Joined Nov 22, 2017
1,189
Im making a circuit with a 555 timer to transmit 512hz through the air. Right now it only travels inches... how can I get the signal to travel a few meters?
This is for a device called sonde... the sonde recieves a signal
Place wire by floor perimeter.
Connect wire to transmitter.
Play with value of R.
Your sonde should receive signal in any point of room.
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Last edited:

Deleted member 115935

Joined Dec 31, 1969
0
radio distance,
assuming you have a chosen frequency modulation

is set by

a) power into the aerial
b) gain of the transmitting aerial
c) gain of the receive aerial
d) sensitivity / gain / discrimination of the receiver

which of these can you change ?
 

DickCappels

Joined Aug 21, 2008
8,000
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Connect the output of your NE555 to the left hand side of the 100 pf capacitor to cause the 2N3904 to avalanche on the positive edge of each pulse. That will give you a dv/dt of 30 gigavolts/second. The antenna is a small untuned capacitive radiator.

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"Video Out" is a signal that will go high when the NE555 is transmitting. The signal will be very small and will need amplification and processing to be useful.

Both the transmitter and detector needs a connection to ground to work well. That can be through the ground pin in an AC outlet. What you get is ultrawideband at ULF. I am not sure where in the world this mode is authorized.
 
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