SHOWALL FUN PRANKS HIGH VOLTAGE LAZARUS-64 PHOTOGRAPHY SPY GADGETS VIDEO GAME
Figure 28 - The completed stick and run Spy Transmitter
Figure 28 - The completed stick and run Spy Transmitter

After sticking the circuit board to the battery casing, I had to retune the unit again to place it back on a nice high dead band on the FM radio. Higher frequencies are better because there is less crackle on the receiver, allowing for a cleaner reception. The position of the tiny antenna was also important, as any changes would throw off the transmit frequency. You may actually find better performance using a shorter and more rigid antenna that is not easily bent around.



Figure 29 - Bugging my own stock room to protect it from pirates
Figure 29 - Bugging my own stock room to protect it from pirates

The simple transmitter worked fairly well considering how few components it has, and from a fresh 9 volt battery has been running for many hours. In fact, I have not run down a battery yet in all of my tests, including the time I forgot to unplug the battery. The transmitter uses such a small amount of current that even a 3 volt coin cell will run it for many hours, which is what prompted me to make the second size reduced version.

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