V
H
F

U
H
F

L

<--S-->

<-------C------->

2GHz to 4GHz

4GHz   to 9GHz

9 GHz  to 12GHz

12GHz to  18GHz

18GHz to 26GHz

This was the first matched RF connector. It was done during WWII for high frequency applications. The N connector is characterized by a 5/8-24 mating thread and an air dielectric interface . It is best suited for use with cables having a jacket diameter from .250 to .450 inches. Connectors have been made for smaller as well as larger cables. The N series has good RF performance parameters. The air dielectric limits its voltage handling capacities. The N series is the most popular of the medium size connectors. The N connectors are covered by Mil-C--39012 slash sheets 1 through 5, and 129 through 132.

C SERIES

This is similar in size to type N connectors, however, they are bayonet locking. The C series uses a teflon dielectric for its interface. The dielectric overlap enables better voltage handling capabilities. The bayonet coupling does not perform well electrically during vibration. C connectors are covered by Mil-C-39012 slash sheets 6 through 15.

HN SERIES

These are slightly larger than type N connectors, but use basically the same cables. They have a 3/4-20 mating thread and have a teflon interface. They are designed to have increased voltage capabilities without realizing the loss of its RF parameters. The Navy is using HN's in their submarine sonobuoy program. HN connectors are covered by Mil-C-3643.

SC SERIES

This often is referred to as the Screwed C. It was developed to overcome the shortcoming of the C and HN connectors. Its has a 11/16-24 mating thread. The SC is popular in Military aircraft and areas which have high vibration. The SC connectors are not more widely used because of their price. They are covered by Mil-C-39012 slash sheets 35 through 43.

BNC SERIES

This is the most popular RF connector. It features a bayonet coupling. It is recommended for use with cables ranging from .150 to .250 inches. Since it is such a popular connector, it has been made for a much wider range of cables. They are very widely used in the instrumentation field. They are limited in frequency because of their bayonet coupling. The BNC connector can be used where quick connect/disconnect is desired yet positive locking is needed. BNC connectors are covered by Mil-C-39012 slash sheets 16 through 24.

These are high voltage versions of the BNC. The SHV was designed to replace the MHV. It was felt the MHV was an unsafe connector since the ground connection was broken before power connection. The SHV was developed by NBS for high energy physics applications. Both series were recently incorporated into Mil-C-39012, however, the MHV series was immediately inactivated and replaced by the SHV. MHV connectors were covered by Mil-C-39012 slash sheets 100 through 104. SHV connectors are covered by Mil-C-39012 slash sheets 105 through 111. Both MHV and SHV were not designed with the intentions of meeting RF performance parameters.

TNC SERIES

This is a threaded version of the BNC. It has a 7/16-28 mating thread. The TNC's have high frequency capabilities because of their more stable mating. They are popular where the larger SC and N connectors are too big but a threaded coupling is needed. TNC are covered by Mil-C-39012 slash sheets 26 through 34, and 112 through 116.

SMA SERIES

This high performance subminiature connector. They are characterized by a 1/4-36 mating thread and a butt outer contact. They usually have passivated or gold-plated stainless steel bodies. They were designed originally for use with .141 semi-rigid cable. When used with this cable, the optimum performance can be obtained. It is not always desirable to use semi-rigid cable since it is awkward to work with, but when the more popular flexible cables are used, it is not recommended to use the SMA connector above 12.4 GHz because the cables are not rated that high. The drawback with the SMA series is the butt outer contact, if the connector is not properly mated, the RF parameters will be degraded. The SMA is commonly used with cables ranging from .085 to .220 dia. The SMA is a very widely used connector in high performance military systems and state-of-the-art test equipment, as well as where miniaturization is desired. The SMA connector for flexible cables and receptacles are covered by Mil-C-39012 slash sheets 55 through 63; connectors for semi-rigid are covered by slash sheets 79 through 83, and slash 92 through 94.

This is another subminiature threaded connector. It is characterized by a #10-32 mating thread and brass, gold-plated body. It does not have the performance capabilities of the SMA. It is used where miniaturization is needed but high performance is not. It issued with cables ranging from .045 to .140 dia. SMC connectors are covered by Mil-C-39012 slash sheets 73 through 78

SMB SERIES

This is a snap-on version of the SMC. It is more limited in performance due to its coupling means. It is used where room for threading and unthreading is unavailable. SMB's are covered by Mil-C-39012 slash sheets 67 through 72 and 95 through 96.

75 Ohm SMB/SMC - Both the SMB and SMC have 75 ohm versions available. They are very popular in the Telecommunications industry where it is designed to keep attenuation to a minimum. These interfaces are not coordinated through a military or industry standard. The larger corporations such as Rockwell/Collins have their own interface requirements which guarantees interchangeability. These 75 ohm versions are slightly larger than their 50 ohm counterparts.

PMA SERIES

This is a proprietary series developed by Automatic Connector. Its performance is comparable to the SMA. The PMA has a wiping outer contact and is designed for use with cables from .110 to .220 dia. It features a float mounting achieved through a coil spring.

PMMA SERIES

This is another proprietary series developed at Automatic Connector. It is a miniaturized version of the PMA, with improved electrical performance through 18 GHz. It is designed for use with cables ranging from .085 to .140 dia.

BSM and TSM SERIES

These are low performance subminiature connectors. They are very popular in land mobile radios. The Automatic BSM connectors are interchangeable with the Amphenol MB series and Kings KM series. These are commonly used with cables ranging from .110 to .250 dia.

ADM SERIES

This is a family of coaxial contacts which can be used in D-subminiature type blocks. These are interchangeable with Cannon, Cinch and Palco contacts.