RFC-400 vs RG-58: A Major Upgrade for Your Antenna System
RFC-400 is a low-loss 0.400" coaxial cable equivalent to LMR-400, while RG-58 is the classic thin flexible cable that has been the affordable standard for decades. The performance difference between them is dramatic — RFC-400 delivers less than half the signal loss of RG-58 at VHF frequencies.
The Short Answer
RFC-400 is worth the upgrade for any permanent installation over 15 feet. The signal quality improvement is immediately measurable and the cost difference is modest compared to the value of a better antenna system.
Key Differences at a Glance
- RFC-400 at 144 MHz: 1.5 dB/100ft vs RG-58's 3.9 dB — 2.6× less loss
- RFC-400 handles 700W at 150 MHz; RG-58 is rated for only 150W
- RFC-400 has UV-resistant jacket for long-term outdoor use; RG-58 PVC degrades
- RFC-400 is significantly stiffer than RG-58 and requires a 2" bend radius
- RFC-400 delivers LMR-400-equivalent performance at a lower price point
Side-by-Side Specifications
| Specification | RFC400 | RG58 |
|---|---|---|
| Impedance | 50 Ohm | 50 Ohm |
| Frequency Range | DC – 6 GHz | DC – 1 GHz |
| Velocity Factor | 0.85 | 0.66 |
| Dielectric | Foamed PE | Solid PE |
| Shield | Aluminum foil + tinned copper braid | Tinned copper braid (95%) |
| Jacket | PE | PVC |
| Center Conductor | Bare copper clad aluminum, 2.74mm | Tinned copper, 19×0.18mm |
| Min. Bend Radius | 2.0 in (50mm) | 1.0 in (25mm) |
| Max Voltage | 600 VRMS | 1400 VRMS |
| Temperature Range | -40°C to +85°C | -40°C to +85°C |
| Weight | 5.0 lb/100ft | 2.2 lb/100ft |
Attenuation Comparison (dB per 100 ft)
| Frequency | RFC400 | RG58 | Difference |
|---|---|---|---|
| 100 MHz | 1.5 dB | 4.3 dB | +2.8 dB (RG58 worse) |
| 450 MHz | 3.3 dB | 9.8 dB | +6.5 dB (RG58 worse) |
| 900 MHz | 4.7 dB | 14.3 dB | +9.6 dB (RG58 worse) |
| 1.8 GHz | 6.8 dB | 21.5 dB | +14.7 dB (RG58 worse) |
| 2.4 GHz | 7.9 dB | 25.5 dB | +17.6 dB (RG58 worse) |
| 5.8 GHz | 13 dB | 44 dB | +31 dB (RG58 worse) |
When to Choose Each Cable
Choose RFC400 when:
- Base station feedlines over 15 ft
- VHF/UHF and cellular applications
- Any permanent outdoor installation
- Cellular booster antenna runs
Choose RG58 when:
- Short temporary jumpers
- Portable operation
- HF-only at low power
- Very tight routing where 0.400" is too large
Frequently Asked Questions
Is RFC-400 the same as LMR-400?
Electrically, yes — RFC-400 matches the LMR-400 specification for impedance, velocity factor, and attenuation. It is manufactured to the same standards at a lower cost.
What connectors fit RFC-400?
RFC-400 uses connectors designed for 0.400" cable — the same as LMR-400. N-type, PL-259/UHF, and SMA connectors in LMR-400 size all work with RFC-400.
Build Your RFC400 or RG58 Cable
Pick your connectors, choose your length — hand-assembled and shipped free in the USA.