Understanding and choosing GHz-range coaxial connectors and cable assemblies
One available RP-SMA jack connector is the panel mount, through-hole solder
Figure 15: Reverse polarity (RP) connectors are available in range of circuit board styles as well as cable termination configurations. (Image source: Würth Elektronik)
63012042124504 (Figure 16). This connector features a VSWR of 1.2 from DC to 12.4 GHz, and 1.4 from 12.4 to 18 GHz, while the insertion loss in those two ranges is 0.14 dB and 0.2 dB, respectively. Cables and assemblies complete the connections Connectors alone are only part of the RF signal path scenario; their plugs are usually fitted to standard coaxial cables such as RG174, RG316, and RG188, among others. Although all are 50 Ω cables for RF work (75 Ω cables and connectors are available for video systems), they differ in frequency range, attenuation, diameter, dielectric type, phase characteristics, power handling, minimum bend radius, external jacketing, and other mechanical and electrical attributes (Figure 17). Designers must also decide whether to make their own coaxial cable assemblies or buy them already fabricated—the classic “make versus buy” question. It is possible to terminate these coaxial cables with the selected connectors as needed—the “make” option—but doing so is a challenge which takes skill, practice, time, suitable crimping tools, and other tooling in many cases.
Figure 16: The 63012042124504 is a reverse polarity SMA connector designed for through-hole mounting and soldering. (Image source: Würth Elektronik)
and phase shift, to cite just a few factors. These electrical tests take time and require sophisticated measurement equipment, and the assemblies need mechanical ruggedness added via strain relief.
Further, these completed cable assemblies need more than just a simple continuity test; they also need to be checked for RF performance factors such as bandwidth and flatness, impedance discontinuities, loss,
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