Military VHF radio device RUP-12 transceiver

RUP-12 was produced in the company "Rudi Čajavec" Banja Luka in 1966, and replaced the previous low-power tactical VHF radio stations BC-1000, RUP-1, RUP-2 and others made in electron tube technology. In the formation of the JNA units, the RUP12 became the basic radio device of the commander of the infantry company, and it was also used for VHF radio communications in higher commands, where it was mounted in various radio-telephone, radio-teleprinter and other systems.

It worked in the frequency range from 30MHz to 69.95MHz, with frequency modulation on 800 working channels. The frequency was controlled by a frequency synthesizer with direct synthesis, and was adjusted with three switches in steps of 50KHz. The output power of the transmitter was from 0.9 to 1.8W. It was powered by a DC voltage of 12V. At the beginning, the power supply was provided by a 12V/6Ah lead battery or a BAJ-13.5 (13.5V) dry battery. Later, the power was supplied from a 7Ah NiCd battery manufactured by "Krusik" Valjevo, or from an external DC source of 12V or 24V via a PT-6 converter. The device consumed 85mA on reception, and about 750mA on transmission. The weight of the portable set with the battery is 12 kg.

The range of the RUP-12 depended on the antenna used and the place of installation. In the plain, with a long rod antenna, it was 8 to 12 km. By connecting two devices with a suitable adapter (cable for retransmission) and placing them in a high place, a signal retransmission station (repeater) could be formed and thereby increase the range between end devices. It was performed automatically or manually depending on the signal strength of the end participants because it was activated by the signal from the noise suppressor.

The RUP-12 was made entirely in transistor technology, and they were mostly domestically produced. The sensitivity of the receiver was 1.2 µV. The bandwidth in the intermediate frequency amplifier was limited by a 10.7MHz crystal filter manufactured at the "Mihailo Pupin" Institute, and a good selectivity of +/-15kHz was obtained from the medium carrier frequency for an attenuation of 5dB. The deviation of the operating frequency of the transmitter from the nominal one was less than +/-2kHz.

. Origin: Yugoslavia