Pre-amplifier vs Distribution Amplifier

Table of Contents

Introduction

When setting up a TV antenna system, understanding the difference between a distribution amplifier and a pre-amplifier is important as each serves a distinct purpose based on setup and requirements.

Here’s an overview of their differences.

Pre-Amplifier

A pre-amplifier, often called a preamp, is used to boost the signal strength right at the antenna before any signal loss occurs due to long cable runs or splitters.

Channel Master CM-7777HD Amplify Adjustable Gain TV Antenna Preamplifier with LTE Filter | Indoor/Outdoor

Here are some key aspects of preamplifiers:

  • Location: It is installed close to the antenna, often directly on the antenna mast.
  • Function: The primary function is to amplify the signal received by the antenna to a level that can compensate for loss in the cable and any other passive components like splitters down the line.
  • Benefits: By boosting the signal at the source, a preamplifier can significantly improve the reception of distant or weak signals before they degrade through the transmission process.

Key specifications

  • Preamps typically have low noise figure – ideally less than 1 dB, although most commercial offerings are less than 2 dB. The NF of the Winegaard shown below is 1 dB typical.

Winegard LNA-200 Boost XT HDTV Preamplifier, TV Antenna Amplifier Signal Booster, HD Digital VHF UHF Amplifier,Black

  • Preamps have one RF output.
  • The Gain is at least 10 dB

Distribution Amplifier

A distribution amplifier, on the other hand, is used further down the signal path and is primarily designed to compensate for signal loss when distributing the signal to multiple TVs or throughout a large building.

Channel Master TV Antenna Distribution Amplifier, TV Antenna Signal Booster with 4 Outputs for Connecting Antenna TV to Multiple Televisions (CM-3424),Black

Key aspects include:

  • Location: It is typically installed where the coaxial cable splits to go to multiple televisions or outlets.
  • Function: The main function is to amplify the signal after it has been split to maintain adequate signal strength to each output, ensuring that all connected TVs receive a strong enough signal.
  • Benefits: Especially useful in setups where one antenna feeds multiple televisions or when the signal has to travel over long distances after splitting.

Key Differences

  • Purpose: Preamplifiers boost weak signals at the source to overcome losses in long cable runs, while distribution amplifiers boost the signal strength after it has been divided, to ensure all splits have adequate signal levels.

Channel Master TV Antenna Distribution Amplifier, TV Antenna Signal Booster with 4 Outputs for Connecting Antenna TV to Multiple Televisions (CM-3424),Black

  • Installation Point: Preamplifiers are placed close to the antenna, minimizing initial signal loss. Distribution amplifiers are installed where the signal is distributed to multiple outputs.
  • Use Case: Preamplifiers are ideal for situations where the antenna signal is weak or the antenna is far from the TV. Distribution amplifiers are ideal for setups that involve multiple TVs or long cable runs post-split.

Key specifications

  • Distribution amps typically have lower gain per channel. The table below shows the gain for each port in channel master products
PortsMax Gain
130 dB
47.5 dB
84.5 dB
  • The noise figure is not a critical specification

Summary

Choosing between these two types of amplifiers depends on the specific issues you’re facing with your antenna setup—whether it’s weak signals at the source or signal degradation due to distribution needs.

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Channel Master CM-7779HD PreAmp 1 TV Antenna Amplifier with 5G LTE Filter, Adjustable Gain Preamplifier - Professional-Grade Signal Booster