You can use literally any RF or microwave transistors. KT 368 (from the HF series) or KT 325, KT 399 (from the Microwave series) are perfectly suited. When using microwave transistors, the range increases to 50 meters. The circuit contains 5 - 6 turns of wire with a diameter of 0.5 - 0.7 mm, wound on a frame with a diameter of 4 mm. The circuit itself is quite simple and was taken from a radio bug scheme. The transmitting circuit has been replaced, the circuit has been changed so that it generates interference on the amp - band, because it is on these bands that many television and radio channels work. A piece of copper wire with a length of 20 - 15 cm serves as the antenna, the latter can be excluded, but then the distance decreases. By rotating the variable capacitor, the device can be configured to directionally suppress channels that are in close ranges. The power of the device is enough for the targeted suppression of 2 - 3 television or radio channels.
The jammer can be powered from 4 to 12 volts. For this purpose, the crown or corundum or any constant voltage sources for which the specified output rating is perfect. A precise device can also be implemented using microwave field effect transistors. The values of the used radio components can be rejected in one direction or another, we are talking about resistors, because the capacitors in the circuit are critical and even with a deviation of 1 picofarad, the circuit may not work at all or work with "ailments" - short range, high current consumption, unstable work, etc.
The current consumption of the jammer should be somewhere around 5 - 7 mA from the crown. In order to reduce power, you can increase the emitter resistor value of 100 ohms. Thanks to this, you can achieve power in a couple of watts. Using powerful field effect transistors, you can suppress (jam) the GPS range, and therefore mobile communications, we will talk about a similar design next time.
