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Spy Circuits

Strona 13 z 46

See the layout below:

Faults with this Circuit:

1. Load resistor for microphone is > 47 k

2.10u on output of microphone is n sufficient.

3.    Current through audio State is vś resistor should be 47k

4.    Base biasing of oscillator very w

5.    Load resistor for oscillator (emitt Iow

6.    Feedback capacitor for oscillatoi

7.    No ceramic in tank Circuit. Addin it easier to adjust

the trimmer capacitor.

8.    No capacitor across the battery.

Birds-nest of above Circuit showing how tight the Circuit can be madę

There is nothing wrong with a bird's nest. It is very easy to experiment with components and wiring that can be seen and changed without having to work on a PC board. The only problem with the bird's nest above is the lack of an earth piane. When you have an earth piane, the signal can push against the large mass of an earth raił (or battery) so that it can push the signal out the antenna.

2011-12-08

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