Smallest wireless transmitter?

Using Arduino Project Guidance
1

I need an extremely small wireless transmitter that can connect to an arduino or something smaller. The signal only needs to travel about a meter and the size of the receiver doesnt matter. Anyone know of anything?

2

http://www.hoperf.com/rf/fsk/21.htm

3

anything smaller?

4

It might be worth considering infrared at that range, depending on the data rate you were hoping for. The transmitter can be as simple as an LED + resistor.

-br

5

should be 5mm x 5mm at most

6

peterpan:
should be 5mm x 5mm at most

What kind of and amount of data do you need to send. Infrared transmitting can be very small for the transmitter part. Think how tiny the smallest LED you ever saw was.

Lefty

7

a transistor + a couple of caps + resistor + a wire = a transmitter;

an active crystal oscillator controlled by your mcu pin + a wire = a transmitter;

a mcu pin flipping fast and furious + a wire = a transmitter;

...

8

dhenry:
a transistor + a couple of caps + resistor + a wire = a transmitter;

an active crystal oscillator controlled by your mcu pin + a wire = a transmitter;

a mcu pin flipping fast and furious + a wire = a transmitter;

...

I need a very small receiver. I can go upto about 8mm by 8mm. I only need it to toggle a small 3v motor on or off when it receives a signal. I'm not too woried about the size of the transmitter. Although the receiver will be less than 10Mtrs from the transmitter, it won't be possible to use IR as the receiver will be hidden when in use. Any suggestions?

9

These are pretty small for both Rx & Tx, built in antenna.
Not 8mm x 8mm small, but pair it up with an ATTiny perhaps to receive on/off command and control MOSFET to turn motor on/off.

http://www.mdfly.com/index.php?main_page=product_info&cPath=8_52&products_id=81

10

retrolefty:

peterpan:
should be 5mm x 5mm at most

What kind of and amount of data do you need to send. Infrared transmitting can be very small for the transmitter part. Think how tiny the smallest LED you ever saw was.

Lefty

Just need to send a button pushed signal but there cannot be any delay. Doesnt infrared have a bit of delay? At least according to my experience with TV remotes, or is that just the tuner being slow? If the is a delay it should be under 50ms in total

11

At 1 metre range you don't need a transmitter on the remote device.
Assuming you want to "see" a circuit open or closed all you need is a tuned coil to act as your "transmitter".
Your base receiver unit is actually a "grid-dip" device (now there's a term from the past`) which is tuned to the resonant frequency of the remote tuned circuit. When the tuned circuit is open there is no absorption of the base signal but when the tuned circuit is closed there is absorption.