Tektronix TEK VX4820 Digital Test Module VXI 1.3 HW REV. 671-2435-01Tektronix TEK VX4820 Digital Test Module VXI 1. 3 HW Rev. 671243501 A VXIbus digital I O module for generating and capturing logic signals on automated test systems. The VX4820 offers 32 TTL CMOS channels with programmable drive levels and realtime pattern sequencing. Key Specifications Standard: VXIbus VXI1. 3, Csize module Channels: 32 bidirectional digital I O Logic Levels: TTL CMOS selectable Throughput: Up to 100 MHz toggle rate Memory: 64 kword