Modifications
This is a cross-wiki mantained doc.
CX Cards are very cheep and flexible ADC chips as they can be modifyed for more sampling abbility, signal filtering and connectors can be replaced and so on not only do they use standard parts but stanard footprints for connectors and are also low cost enough to the point of not a high loss if mods fail badly.
BNC Mod / Crystal Mod / C31 Mod
This is primiary a soft mod as your just connecting an external amplifyer, however you can adjust the physical board compoents for better handling this is a tinker and see thing.
This is the act of replacing the stock crystal with a faster rate crystal, note this crystal needs to be a fundamental type 3rd overtone will sometimes work but at lower rates.
At stock the CX Cards use a 28.63636 Mhz Crystal, this can be replaced with 40 Mhz fairly easily.
The max the CX chips support is 48Mhz to 54Mhz (acording to the datasheet and testing) though this is rare to work outside the CX23881 version of the chip.
40Mhz Crystal: ABRACON ABLS2-40.000MHZ-D4YF-T Digikey / Farnell (can be sorced from most vendors)
With higher sample rates or just long duration capture more cooling to keep the CX chip at a stable temrpature is required in some cases but best practice in all cases for heat genarating silicon hardware.
Installation: Clean top of CX Chip with 99.9% IPA, then apply thermal pad or thermal paste, ensure the heatsync does not contact with any electronic componets its best to capton tape the heatsync and or surrounding componetents.
Requirements: 40mm heat sync & fan / Thermal Pad / Thermal Paste / Silicone Glue / Kapton Tape
Blue cards come with BNCs but are not the most optimal cards, white cards come with RCA (both have S-Video or Y/C as well) as there is drop-in replacements avalible.
This requires de-soldering wicking & flush cutters,
The stock metal bracket will also need expanding by 1-2mm.
A Dremal with an small sanding bit or and a cutting wheel, or fine metal file is required for this.
Conformal coating is a layer of insulation this can provide light signal proofing and water/corrision and debris protection.
By adjusting low pass filtering you can, get a softer or sharper look to images, this mainly applys to LD or LaserDiscs for capture however so tape users can mostly ignore this segment.