[Coco] A little off topic

[Melanie and John Mark Mobley]

Regarding a miniature RF transmitter...

The auto-transformer or coil is made from magnet wire. 

When working with magnet wire it is important to realize that the wire is
coated with something like shellac, varnish, or enamel.  This insulates the
wire and allows you to wrap the wire in many turns next to each other on top
of each other without creating a short.  When it is time to make a
connection you must remove some of the insulation.  You can use sandpaper or
a hot soldering iron with rosin core solder.

The following is guess work only...
These are some ideas to decrease the power of the transmitter...
Because you are trying to make a short range transmitter you can try:
1) A short antenna
2) A leaky coax for an antenna
3) A loop antenna
4) A lower power supply voltage
5) A series resistor on the antenna
6) A load resistor/terminating resistor on the antenna
7) A resistor on the emitter of the transistor (like 1-ohm).

John Mark Mobley