[c-nsp] DS3 Cables

[Jeff Chan]

As Jay mentions, the correct patch cable type for DS3s is 734 or 735.  The
connectors must be true 75 ohm or there will be reflections to and from the
cable (think antennas and ghosting), probably resulting in lower signal to
noise ratios, etc.  Never use 50 ohm connectors or cables for this application.

We have both built and bought cables, with excellent results.  We sourced single
and multiple circuit 734 cables from large cable vendors, and I hand-terminated
them Canare 75 ohm BNCs with Canare stripping and crimping tools.

We have also bought assembled RG6 cables (Belden type 1694 type) terminated with
Kings connectors from Markertek and they seem to work perfectly.  These are
listed as HDTV cables.  (We also bought the Canare connectors and tools from
Markertek.  Canare also makes excellent cabling, equal to or better than
Belden.)

  http://www.markertek.com/

 
http://www.markertek.com/SearchProduct.asp?item=1694%2DB%2DB%2D3&off=18&sort=prod

The key principles are that the connectors must be 75 ohm, and the larger
diameter 75 ohm cables have lower losses per unit distance.  The larger cables
are also quite stiff, so use large bend radii, etc.  The telco type 734 and 735
seem to have tougher and thicker jackets than commercial coax cables.

Jeff C.