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Welcome to the cxadc modified driver wiki!

Summary

This is the CXADC Wiki written and maintained by Harry Munday (harry@opcomedia.com), Inside this wiki and its pages, you will find general information alongside technical guidance and notations for modifying CX Cards, and obtaining effective captures of signals with them.

Concept of CXADC

Takes the cheep and common Conexant CX2388x series of video decoder/encoder chips found on PCI/PCIe TV/Capture cards and turns them into a SDR capture card via simple driver replacement.

At deafult this is 28.6msps stock with 40msps possible on almost all cards via replacing a simple timing crystal (upto 54msps possible).

Crystal Mhz = Max MSPS rate. (2x MSPS = 1Mhz of bandwith)

These CX Chips have a testing mode called RAW16 that allow continuous raw samples to be output to file this is how they are used as a SDR alongside there wide input range ment for CVBS/Broadcast signals.

Uses Of CXADC

• FM Media Capture

• SDR Radio

• Software Ossiliscope

The driving force behind the continued develpment of the CXADC driver and testing/modifying of new PCIe cards is due to the VHS-Decode, LD-Decode and HiFi-Decode project's capturing raw FM signals off analouge media for full lossless archival.

Fetures and Limitations of CXADC

This driver is currently limited to 8 CX Cards per system.

The Driver supports both 8-bit and 16-bit sampling (10-bit ADC)

Signal centering or DC offset control is supported.

Windows support, currently there is only a raw driver for Linux, but we hope to make a version for Windows in the near future.