QMA Connectors

The QMA connector is a quick disconnect version of the SMA connector and shares the same internal construction, which allows the connector to have excellent performance up to 18 GHz. Because of the innovative coupling mechanism, a 360-degree butt joint is maintained resulting in low RF leakage. Since the RF line is identical to the SMA series, the QMA connectors also offer the same high power handling capability. This gives the series significant advantages over other quick disconnect connectors.

Mechanically, the QMA series offers a more convenient installation than SMA connectors. Because the interface mates with a snap-on instead of a threaded coupling, there is a significant time advantage. Typically, these connectors can be installed into a system 10 times faster than an SMA connector. Another benefit of eliminating the threaded coupling is the denser packaging. The pitch between connector can be reduced because there is no requirement for wrench clearance. Connectors can be rotated 360 degrees after they are mated which greatly improves the flexibility of installations.

Features and Benefits
  • Snap-on interface for quick and easy installation
  • High power handling capability
  • Rotatable 360° after connection for flexibility with installation
  • Antennas
  • Base Stations
  • GPS

QMA Connectors Specifications


Impedance 50 Ohm
Frequency Range DC - 18 GHz
Voltage Rating 335 Volts RMS Continuous
Dielectric Withstanding Voltage 1000 VRMS Max
VSWR  (Return Loss)  
     DC - 3 GHz 1.052 (-32 dB) Max
     3 - 6 GHz 1.12 (-32 dB) Max
Insulation Resistance  5000 MΩ Min
Center Contact Resistance 2.5 mΩ Max
Outer Contact Resistance 3.0 mΩ Max
RF Leakage -120 dB Max (DC - 3 GHz)
Insertion Loss .06 √(f(GHz)) dB Max
Power Handling 75 W @ 10 GHz @ 25ºC


Temperature Range −40°C to +85°C
Thermal Shock IEC 60169-1 16.4 (-40⁰C to +85⁰C)
Corrosion IEC 60169-1 16.7 (48 Hrs)
Vibration IEC 68-2-64 Random
Moisture Resistance IEC 60169-1 16.3 (96 hrs) Steady State


Mating Cycles 100 Min
Coupling Mechanism Push-Pull
Interface Specification Quick Lock Formula - QMA
Engagement Force 25 N Typ
Disengagement Force 20 N Typ
Note: These characteristics are typical and may not apply to all connectors.
Connector configurations may affect performance.

Interface Dimensions