Coax Quick Reference Data (Amateur Radio Use)​

A graph comparing: RG-58, RG-8X, RG-213, LMR-240, LMR-400 Frequency range covers HF → VHF → UHF.

General Characteristics

Cable TypeImpedance (Ω)Typical ODVelocity FactorCapacitance (pF/ft)Typical Use
RG-17450Very thin0.6630.8Short jumpers, portable
RG-5850Small0.6628.8HF/VHF short runs
RG-8X50Medium0.6630.8HF/VHF base/mobile
RG-21350Large0.6630.8HF base stations
RG-675Medium0.6620.3RX-only, SDR, TV
LMR-24050Medium0.8424.2HF/VHF/UHF
LMR-40050Large0.8523.9VHF/UHF/SHF
LMR-60050Very large0.8723.4Long VHF/UHF runs

Attenuation Comparison (dB / 100 ft)

Cable14 MHz (20 m)50 MHz (6 m)144 MHz (2 m)432 MHz (70 cm)
RG-1743.16.110.218.1
RG-581.73.35.610.0
RG-8X1.32.74.58.2
RG-2130.71.42.44.5
RG-6 (75 Ω)1.01.93.36.0
LMR-2400.91.83.05.3
LMR-4000.50.91.52.7
LMR-6000.30.61.01.7

Maximum Power Rating (Watts, approx.)

CableHF (3–30 MHz)VHF (144 MHz)UHF (432 MHz)
RG-174~300 W~80 W~50 W
RG-58~800 W~240 W~130 W
RG-8X~500 W~150 W~80 W
RG-213~2800 W~840 W~450 W
RG-6~850 W~250 W~140 W
LMR-240~2100 W~660 W~380 W
LMR-400~4800 W~1480 W~830 W
LMR-600~8000 W~2420 W~1350 W

Practical Selection Guide (Quick)

ApplicationRecommended Cable
Portable HFRG-58, RG-8X, LMR-240
Base HFRG-213, LMR-400
VHF/UHF shortRG-213, LMR-240
VHF/UHF longLMR-400 / 600
RX-only / SDRRG-6
JumpersRG-316 / RG-174

Connector Loss

ConnectorVHF (144 MHz)UHF (432 MHz)Notes
PL-259 / SO-239~0.1 dB~0.2–0.3 dBNon-constant impedance, loss rises fast above 300 MHz
N-Type~0.05 dB~0.05–0.1 dBConstant impedance, preferred for VHF/UHF

Note: At UHF, two PL-259 connectors can equal or exceed 10–15 m of RG-213 loss. This is why N-type is strongly recommended for emergency, repeater, and EME work.

Please Note: The values provided above are for reference purposes only. Actual values may vary depending on the manufacturer, product specifications, and other quality factors.