Full analysis of the difference between 1/2 and 7/8 feeders

As a commonly used cable in the communication industry, the differences between 1/2 feeder and 7/8 feeder are mainly reflected in three aspects:

1、Core performance comparison

The 1/2 feeder (outer diameter 1.27cm) has a thin and soft body but significant line loss, making it suitable for short distance indoor wiring, especially for connecting equipment in computer rooms that require flexible wiring.

The 7/8 feeder line (outer diameter 2.22cm) is thick and hard with low line loss, designed specifically for long-distance transmission from base station antennas to feeder holes, with a bending radius of≥21cm.

2、Typical application scenarios

-1/2 feeder: Short distance scenarios such as main equipment and 7/8 feeder transfer sections, machine room jumpers, etc. are strictly prohibited for long-distance transmission.

-7/8 feeder: For outdoor scenarios such as tower base stations, installation requires metal clamps for fixation and windproof horizontal bars for reinforcement. The pipe mouth is protected with flame-retardant PVC sleeves, and the joints must be treated with three layers of waterproofing.

3、Key points of installation specifications

Bending restriction:

1/2 feeder≥12cm, 7/8 feeder≥21cm

Fixed standards:

1/2 Indoor horizontal fixed spacing 1-1.5m, vertical 0.5-1m

7/8 Outdoor bracket fixation should avoid high temperature and strong magnetic areas

Joint process:

1/2 feeder requires waterproof glue to tightly wrap, and screws should be tightened diagonally in three times to 3.5N.m

The gap between 7/8 feeders should be≤1mm, with a standing wave ratio of<1.1. Three layers of waterproofing are required: heat shrink tubing, waterproof adhesive, and self-adhesive rubber tape

4、Performance testing indicators

Standing wave ratio: 2.4GHz≤1.2, 3.5GHz≤1.15, fluctuation<0.05

Loss deviation: hundred meter error≤0.3dB, measured value deviation<5%

Environmental testing: The 7/8 feeder must pass a 48 hour test at 55℃high temperature and high humidity, withstand a level 12 typhoon, and have a fixed displacement of less than 1cm

Selection Guide:

Due to limited budget/short distance wiring, choose 1/2 feeder line

Choose 7/8 feeders for outdoor long-distance/high stability requirements

Focus on inspecting the joint process and waterproof treatment to avoid signal failures.