MICRO SPY FM: schema and electronic realization
SCHEMA MICRO SPY FM:
The present system allows for an FM transmitter, amplified microphone capsule understood, of small dimensions (23 x 41 mm), which operated in a frequency range between 70 and 1 10 MHz. II can be captured by a single remote FM receiver a few tens of meters.
At the end of improving the scope, it is advisable to apply at A piece of wire 75 cm long that has
an antenna role. A single 9V battery is sufficient to power the system.Consumption is only 5 mA. For mounting of components just carefully follow the instructions in the layout diagram.
LIST OF ELECTRONIC COMPONENTS All resistors are of 1/4 watt unless statedotherwise. R = 10 ohm R2 = 10 ohms R3 = 68 ohms R4 = 120 Ohms CI "100 nF ceramic. C2 = 47 nF ceramic. C3 = 470 pF ceramic . C4 = 3.3 pF ceramic. CV1 = 4- 20 pF variable. LI = 0.6 uH coil. Tl = 2N2222 M = micro Capsule. 1 clip for 9 volt battery.
Technical features:
POWER:. 9VoItsc.c
C0NS0MMATI0N: 5mA
FREQUENCY: 70-110 MHz