Senin, 12 Januari 2026

Wireless FM The Tapper Part 2

 We're developing the previously posted Wireless FM transmitter, hoping to make it even more "powerful," as it's nicknamed, "the sophisticated wiretapping device." Therefore, we've added a mic amplifier and another RF amplifier for power output to the existing basic circuit. This will increase the sensitivity of the mic as the wiretapping device and extend its range. And of course, this Wireless II version is an improvement over the previous version, intended to be even more sophisticated. Is that true? Let's prove its awesomeness...

After it was assembled, and...it was truly powerful. The mic sensitivity was much greater, as was the transmission range. At the time, I used a piece of cable no longer than a meter long. Anyone want to try assembling it again? Please do...


Wireless FM Layout. 3 Volt power source from 2 batteries.


The microphone sensitivity can be adjusted as needed by adjusting the VR trimpot on the 10kHz. If using it as a microphone, keep the setting low to ensure good sound. If using it for wiretapping, adjust it to your liking. The result is that even the smallest sounds—crickets, the ticking of a clock, or the faint call to prayer—can be heard clearly on an FM radio monitor. Wow!


Additional Post

Okay, bro... I've included the circuit diagram. Have fun creating...

During a test drive, this wireless receiver could clearly pick up signals from a distance of 20m without an antenna. The range is even better when connected to an antenna with a 50-100cm or longer cable.


Fulfilling Requests

Representing several requests via mobile phone, some requested a simple layout, without the stripe. He...he...he said, "Here I show you one without the stripe and in black for easy tracing. Let's all keep working hard for our nation to progress.

 
Great


 Great

Wireless FM Mic the sophisticated eavesdropper

 


I started my first project, the Wireless FM Mic, a sophisticated wiretapping device. This work was 17 years ago, when I was still a student, in 1994.
I obtained the circuit from MOP magazine at the time. I tried to assemble it several times, but it didn't work until the fourth time.
It was fun to eavesdrop on neighbors' conversations by inserting it into a crack in the wall of the neighbor's house to be tapped, then listening to it through an FM radio receiver in my own home.
This Wireless FM could also be used for communication, and eventually, the whole village could chat over the radio within a 500m radius.
With the microphone's extraordinary sensitivity, it was rightly called the Wireless FM Mic, the Advanced Wiretapping Device, as the title of the MOP magazine article suggests. The circuit is simple, consisting of just two transistors. The first transistor, a 2SC289, acts as an oscillator and also acts as a microphone amplifier.
The second transistor, a 2SC1675, acts as an oscillator amplifier or buffer. This wireless system only requires a 1.5-3 volt battery supply.
The complete circuit diagram is shown in the image below.
                                               Wireless FM Mic Circuit Schematic


Component List :
R1 = 1k
R2 = 47k
R3 = 150
R4 = 33k
R5 = 180
C1 = 222
C2 = 1uF
C3 = 102
C4 = 10p
C5 = 10p
C6 = 222
C7 = 103
Q1 = 2SC829
Q2 = 2SC1675
MC = Mic Kondensor
Koker 5mm
5mm Coil L1 Primary 6 turns Secondary 2 turns Here's the layout: