The SMB "SubMiniature B" connector series was designed as a smaller snap-on coupling replacement for the SMA connector. Gender designation can be confusing, with the smaller 'jack' body containing the male pin and as such the smaller connector is male, and larger connector having the female receptacle. Built in accordance with MIL-C-39012, IEC 60169-10, and CECC 22130, SMB connectors can be mated with all connectors that meet these specification mating diameters regardless of manufacturer.

The SMB connector is not as robust as the SMA connector, and although they perform acceptably well under low-moderate levels of vibration, they are not suitable for harsh environmental conditions where the levels of vibration rise.

Alias
SubMiniature B
Impedance
50 Ω
Max. Operating Frequency
4.0 GHz
Mechanism
History

SMB can trace its origins back to the 1960s. In 1968, it was incorporated into MIL-C-39012 where it received its current designation of SMB.

Applications

SMB connectors are common due to their low cost, and can be found in a range of CPE devices such as cellular modems, SCADA radios, SDR, WiFi routers, and a range of other commercial wireless equipment. SMB connectors are also commonly used in older military hardware. Despite being a reasonably popular connector, the series offers no distinct advantage and is generally considered defunct.

Variations

Connector designs with differing coupling mechanisms (e.g., screw on and push-on) have their own unique series (such as SMC and SMP). A 75 Ω connector variation is available.

Male Dimensions
SMB Male Plug CAD drawing
Legend Min Max
A
2.0800
B
3.6600
3.7100
C
0.4800
0.5300
D
0.1800
E
1.3200
F
2.9700
G
0.1800
H
0.0000
I
1.6500
K
3.3300
3.5800
Female Dimensions
SMB Female socket CAD drawing
Legend Min Max
A
2.0600
B
0.1800
C
1.6300
D
0.1800
0.9400
E
3.5800
F
3.5800