Module Head Stations
Head Stations (HS) are intended for amplification, level equalisation, filtering and summing signals received by on-air antennas of television programs in the meter and decimeter wave range, for further transmission to abonents of community TV reception systems or to individual apartments, cottages, etc.
A Head Station comprises a set of passband low-noise channel amplifiers, converters, terminal power amplifier, summation unit for input integration of all channel amplifiers, and power units.
A specific feature of the Head Station is application of television channel SAW filters with low loss in the passband («low-loss» class). Due to application of SAW filters, a high selectivity of channel amplifiers is provided, together with a considerable reduction of their overall dimensions, and thus, of the entire HS dimensions. The high stability of SAW filters’ parameters and absence of tuned elements improve the manufacturability and reduce costs.
HS has a module structure. Each functional unit is implemented as an independent module, all mounted on a common frame. The frame allows mounting up to seven modules. If a greater number of modules is required, frames can be integrated.
This design allows a fast HS reconfiguration according to the on-air situation on the signal reception spot. Channel amplifiers within HS are implemented in two versions: with independent high-frequency inputs (LСА-1хх) and with inputs coupling the television signal to other channel amplifiers (LСА-2хх).
If required, HS is supplemented with a wide-band low-noise amplifier (LРА-510) that compensates the loss occurred from distribution of the television signal between channel amplifiers.
Terminal power amplifier (LРА-521) is intended for amplifying TV signals after their correction in channel amplifiers.
HS power supply unit is manufactured in two versions: pulsed (GR8-12-1) and linear (LPS-12-Т).
HS composition and configuration is specified by the customer.
Parameter Input low-noise amplifier
LPA-510 Terminal amplifier
Amplified frequency band, MHz 48...862 48...862
Amplification factor, at least, dB 15 30
Noise factor, below, dB 3 7
Maximum output level, dB 112 117
(IM3=60 dB, DIN 45004B)
Input/output resistance, Ohm 75 75
Power voltage, V 12 12
Usage current, below, mA 100 450
Overall dimensions (LxHxW), mm 173х77х35 173х77х35
Parameter Channel amplifier
LCA - xxx
Amplified frequency band within one frequency channel, MHz 10
Outband signal suppression, at least, dB 40
Amplification factor, at least, dB 30
Amplification control range, dB 30
Maximum output level, at least, dBmcV 100
Input/output resistance, Ohm 75
Power voltage, V 12
Usage current, below, mA 100
Overall dimensions (LxHxW), mm 173x77x35