The author decided to assemble a device for suppressing television and radio channels, and the device should be convenient and not noticeable as far as possible, that is, be portable and fit in your pocket.
Materials:
- frequency setting capacitor
- the emitter resistor, which is needed for limiting the current of the transistor
- a circuit and antennas that are designed to modulate interference. (use of stranded wire as antennas)
- transistor KT-325
Description of the manufacture of the device.
The manufactured device has a fairly simple scheme, which is given below.
As can be seen from the diagram, the device - generator, the interference supplier was assembled in fact on one transistor, and therefore does not require heavy costs for parts.
To create a device, you can use any transistors with a high frequency of the boundary of which starts from 300 MHz.
It was in this device, assembled by the author, that the KT-325 transistor was used, the operating frequency of which is 900 MHz, although the Kt-368, C9014, C9018 transistors can be used in the same way ... in general, any high-frequency transistors of low power.
The assembly of the product took place exactly according to the scheme, and if you want to repeat it, then using the above scheme, you should not have any difficulties.
Such a device is capable of suppressing a signal in the range of 60-200 MHz, since it can be tuned to a certain range.
setting the frequency range to suppress a certain signal is done by a tuning capacitor, which is desirable and even needs to be selected with a maximum, fully open capacity of 40 peaks.
Coil winding takes place on a frame with a diameter of 6 mm. The coil contains only 6-7 turns of wire with a diameter of 0.8 mm.
As an antenna, the author used a piece of stranded wire with a length of about 30-40 cm. To more conveniently adjust the range of the device, you can either remove the tuning capacitor from the body of the product, or simply make a hole in it that allows direct adjustment.
The adjustment occurs both due to the capacitor, and due to the coil. To do this, you need to compress or stretch the turns, or shove a ferrite rod or an iron nail to change the inductance.
According to the author, thanks to such a device, you will have the opportunity to deliberately suppress broadcast channels, except satellite, which have a higher frequency than the operating mode of the device. It is also possible to suppress FM-AM radio stations at a distance of up to 30 meters.
Below are photos with a demonstration of the device using the example of a TV.
