Astro-Med EVP1 Overview Astro-Med, Inc. EVP1 Performance Characteristics: Form Factor: Module (proprietary interface/bus) Number of Channels: 16 ch Input Coupling: AC,DC Astro-Med, Inc. EVP1 Measurements/Features: Install up to 2 modules: 32 ch TTL, Switch closure, Event log Input Range TTL or 75 VDC 38 k 1/2 input impedance 10 microseconds min pulse widt Standard recording Tick recording Block/Line recording Block/Off recording