After ATT, the signal passes through the relay contacts two-circuit bandpass filters (BPF) and enters the main Board of the transceiver. Further, the signal through the relay contacts comes to the BPF Board, where an attenuator (ATT) is installed at the input. In receive mode the signal from connector "antenna" is supplied to low pass filters (LPF) that performs the function of the RF filter and providing the coordination of the input of the receiver with the antenna. The bandwidth is determined by the applied quartz filter.īlock diagram of the transceiver (look photo on top). The sensitivity of the receiving path at a signal/noise ratio of 10 dB, not worse than 0.5 mV. Then, with slight modifications have been produced transceiver “DRUZHBA” in Kharkiv. HF transceiver "Desna" was produced in Bryansk from 1996 to August 1998 from November 1999. Type of work - phone (SSB) and Telegraph (CW). But gradually the basic model (ROSA transceiver) was brought to the finished design of the transceiver designed for Amateur radio communications in the short-wave range of 1.8.29 MHz. Initially, the transceiver "Desna" was conceived as a simple design for SSB operation, as the main type of radiation and for repetition by novice radio Amateurs at the station of Young Technology (in the form of a radio constructor). The apparatus may be a base when creating a VHF transceivers. By its parameters, the transceiver " Desna "is not inferior to such well - known to all radio transceivers. Many decisions of course can be subjected to criticism – the creative process is endless, but this design has a complete version of the transceiver, and to engage in alterations and improvements – it is a personal matter of every radio Amateur. The main requirements when choosing units and blocks for the transceiver are repeatability, simplicity while maintaining the maximum achievable characteristics, the use of available today element bases. This design has not any unique solutions, rather it is a constructor of most popular well-known tranceivers. A minimum of scarce items that can be found on almost any radio market, provides an opportunity to repeat the design by many novice radio Amateurs. The lower the baseline noise level, the better the sensitivity.Long-term, for several years, the operation of the transceiver "Desna" showed its high parameters, reliability and, most importantly, ease of installation. It is usually expressed in a signal to noise ratio. The weaker the signal that a receiver can reproduce the better the receivers sensitivity rating. Four main receiver characteristics are? 1) sensitivityĤ) noise Describe Sensitivity? The ability to reproduce a useable output from very weak signals. 3 main requirements of an Efficient receiver are? 1) The receiver must be able to select the wanted signal from all the other signals available at its input, WHILST REJECTING ALL OTHERS.Ģ) The receiver must be able to extract the intelligence contained in the modulated signal.ģ) The receiver must be able to produce an output of sufficient power to operate the output transducer, or other terminal device along with the ability to convert electrical signals to sound waves that the ear can interpret, such as speech or music.
TERMS IN THIS SET (36) What is the purpose of a receiver? A receiver converts electromagnetic energy into usable energy and outputs a reproduction of the original signal.
0 kommentar(er)
