Test & Measuring Equipment

39 TEST & MEASURING EQUIPMENT Part 1: dual-trace oscilloscopes (E) The final article in Julian Nolan"s review of dual trace oscilloscopes deals with the Hung Chang OS-635. The Korean company of Hung Chang is, perhaps, better known for its range of DMMs, frequency sources, and counters, some of which are sold under a variety of retail trade names. The Hung Chang OS-635 is a 35 MHz delayed sweep oscilloscope with a 6 kV CRT retailing at £399 (excl. VAT), which is only about £80 more than one would expect to pay for a "basic" 20 MHz model. The delayed sweep is of the "coarse" var- iety; the instrument is also fitted with trigger hold-off and single sweep modes. The OS-635 is fitted with a standard IEC mains socket. The line voltage is exter- nally adjustable to 100, 120, 220, or 240 VAC. The instrument is not fitted with a swivel stand, but the single position stand pro- vided instead allows easy stacking of the unit. The OS-635 is of average depth and width: 352 mm and 294 mm resp...