Home

The Collection

Welcome to the CATV Equipment collection

With the market identified the Cable TV industry began to design amplifiers to meet the need to amplify more signals and go longer distances.

With newly designed filters to decrease the received audio level they found that adjacent channel interference could be eliminated and 13 channel broadband amplifiers were possible. The amplifiers went from 6 (low band) channels to 12 channels and included the FM radio bands.

Along with the Audio filters there was the need to combine the high and low bands for use in the next generation amplifiers. The industry then created antenna mixing networks and high band + low band combining networks (diplex filters).

With long coaxial cable lengths being used the problem of fluctuating signal amplitude levels due to environmental changes (temperature and humidity). These changes would cause the system to go snowy when the temperature rose and to go into cross modulation when the temperature went down. There became a need for an automatic control to stabilize the signal. These circuits were called either AOC (automatic overload control), ALC (automatic level control) or AGC (automatic gain control).

Here are examples of the amplifiers from that era with the 6 channel early models to the later 12 channel versions. Some have level control and some don’t.

The first Cable TV applications were broadband closed circuit RF based networks used to carry channels within the low band spectrum ( TV VHF channels. 2 through 6).

The 2 main reasons this was identified as a commercial need was to eliminate antennas for each receiver and to bring TV service to non reception areas. These customer applications included TV sales showrooms and multiple dwelling units (apartment buildings, Hospitals, hotels and communities).

What was needed was a point (antenna) to multipoint (Customer TV sets) cable system and amplifiers capable of maintaining signal strength.

Here are some examples of those first amplification devices (300 ohm single channel boosters) and some broadband amplification devices (300 ohm broadband boosters) and the first 72 and 75 ohm coaxial cable amplification devices (broadband 72 or 75 ohm amplifiers) capable of converting a single input to a multiple output (from left to right).