RG178 cable

Cable

RG178

RP-SMA MALE

End A

RP-SMA MALE

$1.00

SMA FEMALE

End B

SMA FEMALE

$1.00

50 Ohm DC – 3 GHz

RG178 — RP-SMA MALE to SMA FEMALE

Custom RG178 cable assembly with RP-SMA MALE and SMA FEMALE connectors. Every cable is hand-assembled, tested, and ships free.

Length Price
1 ft $5.99
6 ft $8.49
25 ft $17.99
Need a different length? Use the Cable Builder

Specs Summary

CableRG178
Diameter1.75MM
Impedance50 Ohm
FrequencyDC – 3 GHz
Velocity Factor69%
RP-SMA MALE InterfaceReverse polarity SMA threaded
SMA FEMALE InterfaceSMA threaded (MIL-STD-348)

About This Assembly

RG178 Cable

RG-178 is an extremely thin 50-ohm coaxial cable measuring just 1.75mm in diameter, designed for space-constrained RF assemblies. Its PTFE dielectric and silver-plated conductors deliver reliable performance from DC up to several GHz. Commonly used for internal wiring in test equipment, medical devices, and cellular module pigtails.

RP-SMA Connector

RP-SMA (Reverse Polarity SMA) uses the SMA threaded coupling mechanism but with the male/female pin convention reversed — the jack has a pin and the plug has a socket. Originally standardized to prevent connection of uncertified antennas to consumer WiFi equipment, RP-SMA is now the dominant connector on commercial WiFi routers, access points, and 2.4/5 GHz antennas.

SMA Connector

SMA (SubMiniature version A) is the most widely used RF connector in the industry, offering a threaded interface that provides a secure, low-reflection connection from DC to 18 GHz. Its compact size, 50-ohm impedance, and broad frequency range make it the default choice for WiFi equipment, software-defined radios, cellular antennas, GPS receivers, and RF test instruments.

Common Applications

This RP-SMA and SMA cable assembly is well suited for ultra-compact internal wiring in test equipment and small wireless modules. The combination of reliable RP-SMA and SMA connectors and custom-cut cable length makes it a practical choice for both field installations and bench setups. Every assembly is hand-terminated, continuity tested, and ships free within the USA.

Other RG178 Configurations

RP-SMA MALE to SMA FEMALE on Other Cables