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The three-program receiver Riga (RTV-64) since 1964 has been produced by the Daugavpils enterprise OTs-78/3. Production at the White Swan Correctional Labor Institution, Latvia. In the networks of three-program wire broadcasting, PT Venta (RTV-61) was used. Their relatively high price (20 rubles) became an obstacle to the extensive development of three-program broadcasting. In addition, they had design and design flaws. (RTV-64) which replaced them, has a good appearance and high reliability. Circuit and design solutions have allowed to reduce its cost price to 11 rubles 90 kopecks, the retail price has also decreased to 15 rubles. The loudspeaker had a different name in various documents, such as: GTV-64 and ATV-64, which may be interpreted as Loudspeaker (D) and Subscriber (A). The receiver has a tape recorder connection for recording. The first program in multiprogramming networks is transmitted over the LF channel, and the second and third programs are transmitted via the HF channels with carrier frequencies 78 and 120 kHz, respectively. For the 2nd and 3rd programs, the PT has the following indicators. Rated output power 150 mW. Sensitivity 170 mV, with an input impedance of 800 Ohms for the working channel and 5 kΩ for the neighboring. The band of sound frequencies is 100 ... 6000 Hz with non-uniformity of 6 dB, taking into account the frequency response of the transmitters. CED - 6% at a frequency of 100 Hz and 3% at 200 ... 4000 Hz. The background level is -40 dB. The power consumed from the network 4.2 watts. The speaker is equipped with a 1GD-6 dynamic loudspeaker. Adjusting controls are placed on the front panel. Network fuses for safety are placed inside the unit. PT was upgraded several times, while the electrical circuit remained the same, and the changes concerned the design. PT released until 1970.