Radio Frequency
9 Volt FM Transmitter Kit by BC338

This new 9 Volt FM Transmitter Kit can transmit over 900 feet in the open depending on aerial used. The tank oscillator coil is built into the circuit board, and has been tinkered with to give the best distance and stability for it's size. The battery supply rails have been well tied together with respect to radio frequencies. The tracks are also thicker making the fm transmitter circuit a single ‘solid’ block eliminating RF currents in different parts of the circuit. This also means the battery no longer has RF on it which makes the whole unit a lot more frequency stable. Can be tuned anywhere in FM band - DIY Kit 18.

Specifications:

* L: 1-3/4" W: 7/8" H: 1/2"
* Requires 9 Volt Battery
* Transmission frequency is user selectable.
* Transmitter can be listened to on any FM radio.

Read More Source: ( Or Buy kit)
http://www.electronickits.com/kit/complete/surv/ck217.htm
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