The Old CATV Equipment Museum
The Early Years: Before CATV

Antenna Booster Amplifiers

Tunable Settop Antenna Booster Amplifiers
Broadband Antenna Boosters

This page describes "booster amplifiers" offered by several manufacturers during the 1940s and 1950s to improve fringe-area reception of broadcast television stations received off-the-air by rooftop or tower-mounted antennas.

Fringe area television reception problems were exacerbated by the relatively poor performance of the television sets of the day:

  • Poor sensitivity (i.e., high noise figure).
  • Poor selectivity, resulting in interference from out-of-band signals, including adjacent-channel television signals.
  • Poor impedance match at the antenna terminals, often resulting in significant signal loss.

In an attempt to address these problems, several manufacturers developed booster amplifiers which could be installed between an antenna and a television set:

Boosters were designed to improve the signal-to-noise ratio (S/N) of the incoming signal in two ways:

  • By improving the noise figure at the first stage of amplification.
  • By amplifying the signals before provide outputting them to the television set.

Boosters were not "high-gain amplifiers," notwithstanding the popular notion to that effect: typical boosters provided only about 6 dB of gain.   Their ability to improve the S/N results primarily from the better (lower) noise figure at the first amplification stage of the booster.   Thus, for example, a booster with 6 dB gain and a noise figure 6 dB better than the TV set's tuner will improve the S/N at the input terminals of the TV set by about 6 dB.

Booster amplifiers were manufactured by several manufacturers, in a variety of configurations.   This section describes two configurations:

Frequency Range
RF Ports
Intended Installation
Power Switch
Special features
Tunable Settop Antenna Booster Single VHF Channel, tunable to any Channel 2-13 300-ohm screw terminals On top of ("settop") or near the TV set to facilitate manual operation by user Front panel for manual operation by user Molded plastic or painted metal housing for settop installation in a residential setting.
Broadband Antenna Boosters VHF Low Band (Channels 2-6) 300-ohm screw terminals On top of ("settop") or near the TV set (within range of the TV set's line cord) Internal relay wired to current-sensing circuitry to detect TV set operation AC power receptacle for TV set

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