Cable
RG178
End A
RP-SMA MALE
$1.00
End B
RP-TNC MALE
$1.00
RG178 — RP-SMA MALE to RP-TNC MALE
Custom RG178 cable assembly with RP-SMA MALE and RP-TNC MALE connectors. Every cable is hand-assembled, tested, and ships free.
| Length | Price | |
|---|---|---|
| 1 ft | $11.98 | |
| 6 ft | $14.48 | |
| 25 ft | $23.98 |
Specs Summary
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.
RG178 Signal Loss
Approximate attenuation at common RF frequencies.
| Frequency | Loss / 100 ft | Loss / ft |
|---|---|---|
| 100 MHz | 7.5 dB | 0.075 dB |
| 450 MHz | 16.5 dB | 0.165 dB |
| 900 MHz | 24 dB | 0.24 dB |
| 1.8 GHz | 35 dB | 0.35 dB |
| 2.4 GHz | 42 dB | 0.42 dB |
| 5.8 GHz | 70 dB | 0.7 dB |
Frequently Asked Questions
What is RG178 coaxial cable used for?
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.
What is the signal loss of RG178?
At 1800 MHz, RG178 has approximately 35 dB of loss per 100 ft (0.35 dB/ft).
What frequency range does this assembly support?
This assembly is rated DC – 3 GHz, limited by the lowest-rated component across the cable and connectors.
What is a 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.
