[Milsurplus] question - on BNC RF connectors

[Jim Haynes]

On Sat, 31 Aug 2013, Mike Feher wrote:

> However, from what I recall, BNCs are interchangeable as the only 
> difference between the two is the dielectric loading within the 
> connector.

Don't think so.  I had a bad experience one time.  We had installed
a computer lab using ThinNet, which was an Ethernet technology that
used RG-58/U coax cable, BNC connectors, and coax tees on the
transceivers when then plugged into 9-pin D style connectors on the
back of the computers.  This came shortly after the original Ethernet
which used 1/2" coax cable and either "vampire taps" drilled into the
side of the cable, or N connectors on the transceivers.

As soon as the lab came into use students were complaining that they
were getting disconnected from the file server machines and losing
their work.  After a lot of head scratching we discovered that we
had bought 75-ohm BNC coax tees, and they made intermittent contact
with the 50-ohm BNC connectors on the cables and transceivers.