Sport E 31-731

The Sport E 31-731 was the first portable television set of Romanian design, fully transistorised, put into production by Electronica in 1973 [1]. It had 30 transistors and 30 diodes (the annex gives 31 transistors) on a single 16 × 33 cm printed-circuit board, a 31 cm picture tube and a wooden cabinet, a transistorised channel selector with continuous tuning and a four-key mechanical programmer, and could run from the 220 V mains or a 12 V battery; the text gives 45 VA from the mains and 22 W from the battery [1]. It protected itself against reversed polarity of the external supply and short circuits of the stabiliser [1]. The project was led by Mihai Dumitrescu [1].

From 1975 the Sport family was also made for international standards, which helped exports to Morocco, Greece, Senegal, Lebanon and Jordan; Sport sets with VHF and UHF tuners for the American RTMA standard were exported successfully to the USA [1]. It was followed by the integrated-circuit portables Sport 261 and Sport 251 (1979) [1]. The export version was the Sport CCIR [1].

In the source table, video sensitivity is given for 6 V rms on the picture-tube cathode, the signal-to-noise ratio on the sound path, and the selectivity values are, in order, the rejection of the own sound carrier and of signals below and above the picture carrier (and, where given, of the IF and the image frequency); the audio response is at −3 dB [1].