Video enhancement for Acorn Archimedes

The Acorn Archimedes, well-known L’ for its speed and good graphics facilities, has a video interface that allows programmers to design a variety of screen modes with the aid of a programmable controller. As so often, this versatility has a drawback: since the controller uses a fixed clock at 24 MHz, the frame frequency decreases[…]

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Angled bus extension for PCs

Angled bus extension for PCs: This 8-bit bus extension card for IBM PCs and compatibles allows you to connect and test insertion cards without having to open the computer. The printed-circuit board shown here is angled and has a 62-way slot connector to accept external boards. The pins of the bus connector are soldered straight[…]

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RC- 5 infra-red receiver for 80C32 computer

‘RC-5’ is the Philips/Sony standard the received bits are shifted into a 16-hit reg-(JUL” for infra-red (IR) remote control of consistent formed by R4 (low) and R5 (hi0). The audio /video equipment (Ref. 1). The second start bit becomes the MSB. When the circuit and the listing were given enable the 80C32 received word is[…]

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4th order single chip filter

High-order filters are normally designed by using two or more 2nd-order sections in series. That means that a 4th-order filter needs at least two opamps. The present filter, however, uses only one opamp, which results in smaller distortion, intermodulation, and so on. Also, there is no internal resonance rise, which typifies combinations of 2nd-order sections.[…]

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