Quick Reference
RG405 Coaxial Cable
50 Ohm • DC – 20 GHz
RG-405 (UT-085) is a 0.086" semi-rigid coaxial cable — smaller than RG-402 — with a solid copper outer conductor delivering superior shielding and phase stability. Commonly used in microwave integrated circuit (MMIC) assemblies, millimeter-wave test setups, and anywhere an extremely compact rigid interconnect is required up to 65 GHz.
RG405 Attenuation
Signal loss in dB per 100 ft at standard RF frequencies.
| Frequency | Loss / 100 ft | Loss / ft | 6 ft | 25 ft |
|---|---|---|---|---|
| 100 MHz | 5.5 dB | 0.055 dB | 0.33 dB | 1.38 dB |
| 450 MHz | 12 dB | 0.12 dB | 0.72 dB | 3 dB |
| 900 MHz | 17.5 dB | 0.175 dB | 1.05 dB | 4.38 dB |
| 1.8 GHz | 25.5 dB | 0.255 dB | 1.53 dB | 6.38 dB |
| 2.4 GHz | 30 dB | 0.3 dB | 1.8 dB | 7.5 dB |
| 5.8 GHz | 49 dB | 0.49 dB | 2.94 dB | 12.25 dB |
RG405 Power Handling
Approximate maximum continuous power (CW) at 25°C ambient.
| Frequency | Max Power (W) |
|---|---|
| 100 MHz | 60 W |
| 450 MHz | 26 W |
| 900 MHz | 18 W |
| 1.8 GHz | 12 W |
| 2.4 GHz | 10 W |
| 5.8 GHz | 6 W |
Construction & Materials
Center Conductor
Silver-plated copper clad steel, 0.51mm
The center conductor carries the RF signal. Material and diameter affect DC resistance, skin effect losses, and overall attenuation.
Dielectric
Solid PTFE
The dielectric insulator separates the center conductor from the shield. PTFE dielectrics offer superior temperature stability and lower loss versus polyethylene.
Shield
Solid copper outer conductor
The outer conductor provides the return path and shields the signal from external interference. More braid coverage means better EMI rejection.
Jacket
None (semi-rigid)
The outer jacket protects the cable from physical damage, UV, chemicals, and moisture. PTFE and FEP jackets handle higher temperatures than PVC.
Velocity Factor
69% (c)
How fast the signal travels relative to the speed of light in vacuum. Higher velocity factor means shorter electrical wavelength per foot — important for phased array and delay-matched applications.
Max Voltage
1000 VRMS
The maximum continuous operating voltage. Exceeding this can cause dielectric breakdown. Relevant for high-power transmitters and pulse applications.
Available RG405 Assemblies
Choose a connector combination to see pricing and order. All assemblies are hand-built and ship free within the USA.
SMA MALE to SMA MALE
From $8.99
SMA FEMALE to SMA MALE
From $8.99
RP-SMA MALE to SMA MALE
From $8.99
RP-SMA FEMALE to SMA MALE
From $8.99
N MALE to SMA MALE
From $9.49
MCX MALE to SMA MALE
From $8.99
SMA FEMALE to SMA FEMALE
From $8.99
RP-SMA MALE to SMA FEMALE
From $8.99
RP-SMA FEMALE to SMA FEMALE
From $8.99
N MALE to SMA FEMALE
From $9.49
MCX MALE to SMA FEMALE
From $8.99
RP-SMA MALE to RP-SMA MALE
From $8.99
RP-SMA FEMALE to RP-SMA MALE
From $8.99
N MALE to RP-SMA MALE
From $9.49
MCX MALE to RP-SMA MALE
From $8.99
RP-SMA FEMALE to RP-SMA FEMALE
From $8.99
N MALE to RP-SMA FEMALE
From $9.49
MCX MALE to RP-SMA FEMALE
From $8.99
3 more configurations available on the RG405 page.
Frequently Asked Questions
What is the impedance of RG405?
RG405 is a 50 Ohm coaxial cable. All standard RF systems (antennas, transceivers, test equipment) use 50-ohm impedance, so RG405 connects directly without any matching network.
What frequency range does RG405 support?
RG405 is rated DC – 20 GHz. At higher frequencies, the attenuation per foot increases, so actual usable range depends on acceptable signal loss for your application.
How much signal loss does RG405 have?
RG405 has 5.5 dB of attenuation per 100 ft at 100 MHz, rising to 49 dB per 100 ft at 5.8 GHz. Use the attenuation table above to calculate loss for any specific length and frequency.
Are CoaxRF RG405 cable assemblies made in the USA?
Yes. Every RG405 assembly is hand-terminated and continuity tested at our US facility. We build each cable to order — nothing is pre-made or drop-shipped from overseas.
Can I order a custom length of RG405?
Yes. In addition to our standard lengths (1, 6, 25, 50, 100 ft and longer), we accept custom-length orders through the Cable Builder. Custom assemblies ship within 1–2 business days.