When specifying a 50Ω RF feeder, the first fork in the road is corrugated rigid (copper- or aluminium-tube) vs braided flexible. Both are 50Ω, both can be low-loss — but they win in different situations. This guide helps you pick by frequency, span and how the cable gets installed.
| Factor | Corrugated Cu/Al tube | Braided (PTL/LMR-style) |
|---|---|---|
| Attenuation (same size) | Lower (solid outer conductor) | Slightly higher |
| Shielding effectiveness | Very high (≈90+ dB) | Good (60–85 dB, foil+braid) |
| Flexibility / bend radius | Low; needs careful routing | High; tight bends OK |
| Power handling | Higher (better heat dissipation) | Lower |
| Installation speed | Slower, clamps needed | Faster, pull through trays |
| PIM performance | Excellent (no woven joints) | Good with quality construction |
| Cost (per meter) | Higher material cost | Lower, easier logistics |
Go corrugated. A 1/2″–1-5/8″ corrugated copper or aluminium-tube feeder minimizes loss on long high-power runs and resists weather and interference. For permanent, low-maintenance installs this is the default.
Go braided flexible. In distributed antenna systems and tight equipment rooms, PTL240–PTL600 braided coaxial (LMR-equivalent) bends around structures and pulls through trays without special clamps.
Go braided super-flexible. Where the cable is moved during commissioning or events, flexibility avoids fatigue failures.
Use a leaky-feeder (radiating) coaxial — a specialized corrugated design that leaks signal controllably along its length.
If the run is long, fixed, and high-power → corrugated tube.
If the run is short-to-medium, routed in tight spaces, or moved often → braided flexible.
Many sites use both: corrugated trunk from tower base to roof, braided jumpers into the radio — combine for best loss and installability.
Corrugated cables terminate in 7/16 DIN or 4.3-10; braided in N or SMA. Mismatched or poorly torqued connectors will erase the cable's low-VSWR advantage (see our VSWR guide).