Repeater Office
The outdated term amplifier office (also: "main amplifier office ") stands for wired relay stations that amplify electrical communication signals. The term comes from the time when the operation of the public telephone network in particular fell under state administration.
With amplifiers (in the early days with tube amplifiers ) the levels of TF , telephone, radio and television signals are raised in order to compensate for the cable losses on long lines and to connect existing radio links .
Some amplifier offices were also able to switch individual channels or channel groups to other lines or to recombine channel groups if necessary. The use of fiber optic cables for long-distance lines means that optical amplifiers are used.
Amplifier Office Rheda-Wiedenbrück
In the amplifier office in Rheda-Wiedenbrück , which today serves a small part as a museum, tube amplifiers with battery operation have been in use since 1938 . The operating data were 220 volts anode voltage , 180 volts screen grid voltage , 12.5 volts heating voltage in recharge mode and 40 volts negative grid bias voltage in discharge mode (to avoid ripple voltage ) and charging of the second grid bias battery in readiness to switch over when the first battery approaches the discharge point. An emergency power generator was used to bridge the power failure. The operation was stopped in 1995.
Amplifier Office Frankfurt am Main
A carrier frequency and a low frequency repeater office were set up in the telecommunications office operated at a central location on the Zeil in Frankfurt am Main . The batteries required were the largest of the Deutsche Bundespost at that time . The capacity for the anode voltage was approx. 11,000 Ah , that for the negative 60 V grid bias voltage was approx. 16,000 Ah. Their total weight was about 500 tons. Over 120 tons of battery acid were needed to fill it .
Unmanned booster offices and booster bins
The compensation of the line attenuation in the case of TF long-distance cables was also taken over by unmanned intermediate repeater offices or by amplifier bins. The monitoring and simple previously defined switching processes in the unmanned repeater offices could be carried out remotely and automatically by remote control devices even from distant manned repeater offices.