Wonder what you think of the TNC, seem to be used a lot in the labs, together
with BNC and N.
BNC, TNC and N connectors are identical on the inside. That is, the
center "hot lead" pin and the outer shield fingers are the same
dimensions. You can plug a N male connector into a BNC female connector
and make a proper connection, though there is nothing to hold it in
place. The only difference between the three types is the outer "hold it
together" mechanisms, and in the case of N that also serves as a weather
seal. Beware however that there are 50 ohm and 75 versions of all of
them, and they should not be connected to one another. Damage to the
center conductor female part will result. There may be other impedance
versions too. The non 50 ohm versions are much more common in BNC and
TNC than they are in N.
Also there is MHV which looks very much like a BNC, yet has the
dielectric extending out further in front on the male connector. Don't
try to plug a MHV male into a BNC female. You will not get the bayonet
turned and latched. MHV is typically used for low current, high voltage
supply to photomultiplier tubes and vacuum gauges.
I like to use N connectors for cables with transmit power on them and
BNC for receive only connections. This results in quality constant
impedance connections for both, and an easy way to avoid getting them
mixed up.
DE N6KB
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