SMB (SubMiniature version B) connectors are coaxial RF connectors developed in the 1960s. This version is smaller than SMA connectors.
They feature a snap-on coupling and are available either in 50 Ω or 75 Ω impedances. They offer excellent electrical performance from DC to 4 GHz.
| Requirement | MIL-C-39012 Paragraph | Specification |
| ELECTRICAL DATA | ||
| Impedance | 50Ω | |
| Frequency range | DC to 4GHz | |
| Contact current | DC 1.5A max. | |
| Voltage rating | 250V rms | |
| Contact resistance | 3-16 | Center contacts : 3.0 mΩ |
| Outer contacts : 0.5mΩ | ||
| Insulation resistance | 3-11 | 1000MΩmin. |
| Insertion loss | 3-27 | 0.6dB max. |
| V.S.W.R | 3-14 | Straight 1.3+0.04f(GHz) |
| Right angle 1.4+0.06f(GHz) | ||
| RF leakage | 3-26 | -55dBm min.between 2~3GHz |
| MECHANICAL DATA | ||
| Engagement force | max. 63N | |
| Mating torque | Not applicable | |
| Life | 3-15 | 500 matings. |
| Contact captivation | 3-14 | max. 15N |
| ENVIRONMENTAL DATA | ||
| Temperature range | : -65℃~+125℃ | |
| Corrosion resistance | 3-13 | MIL-STD-202, Method 101,Condition B. |
| Moisture resistance | 3-21 | MIL-STD-202, Method 106. |
| Thermal shock | 3-20 | MIL-STD-202, Method 107,Condition B. |
| Vibration | 3-18 | MIL-STD-202. Method 204,Condition D. |
| MATERIALS | ||
| Bodies and Male contacts | Brass | |
| Female contacts | Beryllium copper | |
| Insulators | PTFE Teflon | |
| PLATINGS | ||
| Bodies | Gold plated | |
| Center contacts | Gold plated | |