3
OPERATING
A multichannel amplifier consists of highly isolated individual amplifiers for every incoming line. Gain and slope controls of
each amplifier are located between input and output connectors of corresponding line.
Gain regulation is performed by two step attenuators. The first rough control attenuator has 4 possitions with 4 dB steps
and the second fine control attenuator has 4 possitions with 1 dB steps. The gain of amplifier is defined by subtracting joint
attenuation of both attenuators from maximum gain.
Slope control has 4 positions. The value of each position determines the difference of gain at highest and lowest frequencies.
Amplifier SA91L provides voltages 18 V to all horizontal polarization connectors, 14 V to all vertical polarization connectors
and 12 V to Terrestrial TV input connector. The switches on the output side allows disconnect voltages of 18 V and 14 V from
output connectors. This is usefull in large networks for prevention of interference between power supply units, when several of
them are incorporated. The switch on the input side allows disconnecting of voltage 12 V from from terrestrial TV input line to
avoid short-circuiting of power supply if terrestrial amlifier with remote powering is not installed. All voltage sources have short
circuit protection with LED indicators. Green light indicates normal operation. The red light signals that short-circuit emerged in
corresponding line or power supply is overloaded (in the case of overloading 18 V red light will be intermittent). After that amplifier
SA91L must unplugged from mains and network must be repaired. Allow at least 30 sec. before connecting to the mains again.
Amplifier SA91DL is powered from central network power supply (for example SA91L) through horizontal polarization lines.
Both lines regarding DC are interconnected to minimize voltage loss in lines. It consumes up to 0.3 A from 18 V power supply.
Amplifier has connector for auxilary power supply if voltage from central power supply is not accessible. If it is plugged voltage
is distributed to horizontal polarization lines in the same way as SA91L. In every case presence of voltage in lines will be
indicated by green LEDs near the corresponding switch. Voltage 12 V in the input connector of Terrestrial path will be only if 18 V
is present in horizontal polarization lines.
Both amplifiers SA91L and SA91DL has DC through path in every Satellite TV line. It provides flexibility for installation of
power supply units inside the network.
TECHNICAL CHARACTERISTICS
Type
SA91L SA91DL
Frequency
range
SAT IF
950-2400 MHz
Terr. TV
47-790 MHz
Gain
SAT IF, adjustable
22 dB (0 ÷ -15 dB) by 1 dB step
Terr. TV, adjustable
22 dB (0 ÷ -15 dB) by 1 dB step
Slope
SAT IF, switchable
0/3/5/7 dB
Terr. TV, switchable
0/6/12/18 dB
Isolation
SAT/SAT
30 dB
SAT/Terr. TV
30 dB
Noise figure
SAT IF
≤
9 dB
Terr. TV
≤
7 dB
Output level IMD3=60 dB
Terr. TV****
109 dBµV
Output level IMD3=35 dB SAT IF****
114 dBµV
External equipment
through V lines
14 V 0.5 A max. (switchable)
-
powering
through H lines
18 V 1.8 A* max. (switchable) -
through Terr line
12 V 0.1 A max. (switchable) -
DC pass through, switchable through H lines
2 A* max.
Supply voltage limit values, power consumption
198
-
250 V~ 50/60 Hz 7 W**
DC 9-18 V 5 W***
Operating temperature range
-20
o
÷
+ 50
o
C
Dimensions/Weight (packed)
335x135x52 mm/1.18 kg
255x135x32 mm/0.9 kg
*
1 A max. through one line
** without external DC loading; with maximal external DC load - 55 W
*** in line powering of SA91DL through H lines
**** measured using 2 equal signals; output level by DIN45004B - add 3 dB to mentioned above
value