RG178 cable

Cable

RG178

RP-SMA FEMALE

End A

RP-SMA FEMALE

$1.00

RP-TNC MALE

End B

RP-TNC MALE

$1.00

50 Ohm DC – 3 GHz

RG178 — RP-SMA FEMALE to RP-TNC MALE

Custom RG178 cable assembly with RP-SMA FEMALE and RP-TNC MALE 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 FEMALE InterfaceReverse polarity SMA threaded
RP-TNC MALE InterfaceReverse polarity TNC threaded

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.

RP-TNC Connector

RP-TNC (Reverse Polarity TNC) uses the TNC threaded shell with reversed pin conventions, similar to RP-SMA. It is used on some commercial WiFi access points and outdoor CPE antennas, particularly in older Cisco and Linksys equipment, and offers better vibration resistance than RP-SMA in demanding outdoor environments.

Common Applications

This RP-SMA and RP-TNC cable assembly is well suited for ultra-compact internal wiring in test equipment and small wireless modules. The combination of reliable RP-SMA and RP-TNC 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 FEMALE to RP-TNC MALE on Other Cables