LMR-400 vs LMR-600: Do You Need the Bigger Cable?
LMR-400 and LMR-600 are both Times Microwave flagship low-loss cables. LMR-400 at 0.405" is the most widely used feedline in the industry — a balance of performance, weight, and cost. LMR-600 at 0.590" steps up to lower loss at the cost of significant added weight, cost, and reduced flexibility. Most installations do not need LMR-600.
The Short Answer
LMR-400 is the right choice for the vast majority of installations up to 150 feet. Only consider LMR-600 for tower runs over 150 feet, broadcast infrastructure, repeater sites, or commercial base stations where every 0.1 dB matters.
Key Differences at a Glance
- LMR-600 at 900 MHz: 1.6 dB/100ft vs LMR-400's 2.7 dB — meaningful on long runs
- LMR-600 weighs ~10 lbs/100ft vs LMR-400's ~6 lbs/100ft
- LMR-600 minimum bend radius is 4.0" vs LMR-400's 2.0"
- LMR-600 costs roughly 2.5× more per foot than LMR-400
- Both are UV-resistant and rated for direct burial outdoor use
Side-by-Side Specifications
| Specification | LMR400 Times | LMR600 Times |
|---|---|---|
| Impedance | 50 Ohm | 50 Ohm |
| Frequency Range | DC – 6 GHz | DC – 6 GHz |
| Velocity Factor | 0.85 | 0.86 |
| Dielectric | Foamed PE | Foamed PE |
| Shield | Aluminum foil + tinned copper braid | Aluminum foil + tinned copper braid |
| Jacket | PE | PE |
| Center Conductor | Bare copper clad aluminum, 2.74mm | Bare copper clad aluminum, 4.13mm |
| Min. Bend Radius | 2.0 in (50mm) | 3.0 in (76mm) |
| Max Voltage | 600 VRMS | 2500 VRMS |
| Temperature Range | -40°C to +85°C | -40°C to +85°C |
| Weight | 5.0 lb/100ft | 10.0 lb/100ft |
Attenuation Comparison (dB per 100 ft)
| Frequency | LMR400 Times | LMR600 Times | Difference |
|---|---|---|---|
| 100 MHz | 1.5 dB | 1 dB | -0.5 dB (LMR600 Times worse) |
| 450 MHz | 3.3 dB | 2.1 dB | -1.2 dB (LMR600 Times worse) |
| 900 MHz | 4.7 dB | 3 dB | -1.7 dB (LMR600 Times worse) |
| 1.8 GHz | 6.8 dB | 4.4 dB | -2.4 dB (LMR600 Times worse) |
| 2.4 GHz | 7.9 dB | 5.1 dB | -2.8 dB (LMR600 Times worse) |
| 5.8 GHz | 13 dB | 8.4 dB | -4.6 dB (LMR600 Times worse) |
When to Choose Each Cable
Choose LMR400 Times when:
- Tower runs over 150 ft
- Repeater sites and base stations
- Broadcast transmitter feedlines
- Commercial cellular infrastructure
Choose LMR600 Times when:
- Residential antenna runs
- Cellular booster installations
- Ham radio base stations under 150 ft
- Any installation where weight and flexibility matter
Frequently Asked Questions
Is LMR-600 worth the extra cost?
Only for runs over 100-150 feet where the reduced loss meaningfully impacts system performance. For a 75-foot residential antenna run, LMR-400 loses about 2 dB at 900 MHz — acceptable for most applications. LMR-600 reduces this to 1.2 dB, a modest improvement that rarely justifies the cost difference.
Can I mix LMR-400 and LMR-600 in the same installation?
Yes — you can use LMR-600 for the long outdoor tower run and transition to LMR-400 at a bulkhead connector where routing into a building requires more flexibility. Both cables use the same N-type connectors at that scale.
Build Your LMR400 Times or LMR600 Times Cable
Pick your connectors, choose your length — hand-assembled and shipped free in the USA.