1055497-1 Datasheet, PDF (279/320 Pages) Tyco Electronics – RF Coax Products

RF Coax Connectors
Appendix B - White Bronze (Continued)
Low Intermodulation
Products
Dissimilar metals, finishes
and discontinuities within a
coaxial line structure give
rise to Intermodulation
Products (IMP). This is of
particular concern in appli-
cations requiring low levels
of intermodulation, such as
cellular base stations and
antennas. White Bronze
plated connectors offer bet-
ter IMP performance and
lifetime characteristics than
nickel. Due to the similarity
of electrolytic potentials and
the non magnetic proper-
ties of the finish, levels of
intermodulation are com-
mensurate with silver and
far in excess of stainless
steel/nickel connectors. At
the same time the excellent
wear characteristics and
durability of the finish
ensure that the intermodula-
tion life of the connector is
greater than silver. The life
is also improved as a direct
result of the excellent corro-
sion resistance properties
of White Bronze; thereby
minimizing metal/metal
oxide junctions.
Highly Corrosion Resistant
Even under continuous
exposure to harsh environ-
ments White Bronze retains
its aesthetic appearance.
Unlike silver it does not
discolor when exposed to
sulphur, potassium sul-
phides etc., neither is there
any build up in oxide layers
as is the case with nickel.
Furthermore, White Bronze
parts have successfully
passed all international salt
spray tests (MIL, BS,
CECC, IEC).
In conditions of continu-
ously high temperatures
(>100°C) and/or excessive
humidity (>100%) there is
no build up of foreign layers
which may affect contact
resistance.
Low Porosity and No
Reaction with Contact
Surfaces
Less than 2µm of White
Bronze is needed to create
a completely nonporous,
corrosion resistant surface.
Tyco Electronics applies
White Bronze to a thickness
of between 2µm and 3µm.
This compares favorably
with the typical plating
thickness of nickel (>10µm)
and consequently, varia-
tions in plating depth are
significantly less.
White Bronze does not alloy
with brass and since its
coefficient of expansion is
virtually identical to that of
brass, rapid temperature
shocks (-50°C/200°C) do
not cause blistering or
cracking of the plating.
The electrolytic potential of
White Bronze is approxi-
mately that of brass.
Consequently, any White
Bronze plated connectors
in contact with stainless
steel, silver, nickel or nickel
containing finishes carry no
risk of corrosion as a result
of any chemical potential
difference.
Low RF Losses
The relative permeability
(µr) of the Tyco Electronics
White Bronze is 1 giving
rise to low RF losses even
at high frequencies. As a
direct result of the good
conductivity of the finish,
skin depth is minimized fur-
ther reducing insertion loss
and ensuring a better
impedance match across
the frequency range of the
connectors.
Non Magnetic Finish
The Tyco Electronics White
Bronze contains no ferrous
materials and so has no
magnetic properties. This is
particularly desirable in
many RF applications.
Wear and Scratch Resistant
The hardness of the
Tyco Electronics White
Bronze at 300-380HV is
more than double that of sil-
ver and marginally harder
than platings containing
nickel. This gives a scratch
resistance which is rarely
surpassed and makes it
ideal for high mating
applications.
Catalog 1307191
Revised 3-07
www.tycoelectronics.com
Dimensions are in millimeters
and inches unless otherwise
specified. Values in brackets
are standard equivalents.
Dimensions are shown for
reference purposes only.
Specifications subject
to change.
USA: 1-800-522-6752
Canada: 1-905-470-4425
Mexico: 01-800-733-8926
C. America: 52-55-1106-0803
279
South America: 55-11-2103-6000
Hong Kong: 852-2735-1628
Japan: 81-44-844-8013
UK: 44-8706-080-208