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Mode 1 powering options
Power for operation in Mode 1 can be supplied by either of the following options:
na PROception proPSU112X 12 V power unit connected anywhere in any of the
output lines Fig 1(a);
na local AC/DC mains power adaptor such as the PROception proPSA123 connected
to the DC power port Fig 1(b) The adaptor need not be regulated and needs
to have a standard 2 1 mm DC connector with the correct polarity (centre pin
+ve) If a 3rd party adaptor is to be used its output should conform to the
requirements given in the technical data section (page 8)
Note: this amplifier is not suitable for powering from the aerial sockets of DVB-T (DTT
or Freeview) receivers The voltage and current available from such receivers (usually
5V at 30mA) are insufficient
Mode 1 preamplifier option (preamplifier power)
Line-power for a masthead or similar preamplifier is available at the UHF input in
Mode1 The amplifier provides approximately 5V with a current rating of 30mA
max , suitable for powering a PROception proMHD11L or proMHD11M preamplifier
If using other amplifiers take care to ensure that the current rating is not exceeded
Use a preamplifier only when the UHF input signals would otherwise be too low in
level i e where the signal levels from the aerial are low, or where there is an
unusually long cable run between the aerial and the proAMP310X amplifier Always
use the minimum amount of preamplifier gain necessary to obtain satisfactory signal
levels at the amplifier input
Preamplifier power is normally present at the UHF input, but will shut down if the
aerial presents a short-circuit at the input Note that this shut-down is not self-resetting
If preamplifier power is wanted, but has been shut-down by a temporary short circuit,
it must be reset manually by removing power to the amplifier for a few seconds
If necessary, preamplifier power can be permanently disabled by means of an internal
jumper (see Advanced configuration features on page 7)
Mode 1 additional UHF sources
Any additional UHF signal sources such as CCTV camera channels should be combined
with the aerial signal feed ahead of the proAMP310X This is best done using
equipment providing a buffered loop-through arrangement (e g the PROception
proMOD1Mk2 video and audio modulator) or by the use of suitable combining
filters The practice of using wideband combiners is discouraged since it can degrade
signal-to-noise ratios and can cause locally generated signals to be radiated from
the aerial, possibly causing interference to other viewers
Note: where auxiliary equipment connected to the UHF input might be affected or
damaged by the 5V preamplifier power, the latter should be disabled using the
jumper facility mentioned in the previous section
Mode 2 eye count
When using the remote powering option with the proPSU112X the total number of
infrared eyes on the system may need to be restricted The proPSU112X is rated to
supply a maximum of 200mA, and approximately 120mA is drawn by the amplifier
itself Thus the total eye load is limited to 80mA This means that a maximum of
eight industry-standard eyes (each consuming about 10mA) may be connected to
the amplifier outputs This restriction is removed if the PROception proSAT1EYEMk2
eye is used, since this consumes less than 5mA
Up to 10 eyes may be connected without restriction when using the proPSA123 AC/ DC
mains power adaptor
plitting outputs
As with any multi-way amplifier the output signals can be split as illustrated in
Fig 1(b) to provide additional outlet points The PROception proSPL204 splitter is
suitable for this in Mode 1 and introduces approximately 4dB insertion loss
Splitting outputs in Mode 2 is not recommended, since it is not possible to provide
individually protected eye power to the split outputs
ignal levels
This amplifier has relatively low forward gain figures and assumes that adequate
input signal levels will be available from properly installed aerials The amplifier
gains are sufficient to compensate for additional distribution cable losses in a typical
domestic-scale system whilst avoiding the intermodulation and other overload
problems which result from the use of excessive gain
Recommended minimum and maximum signal levels for each of the frequency bands
are given in the Technical data section on page 8 Particular attention should be paid
to the input VHF radio signal levels In city areas very strong signals are often received
and it may be necessary to use attenuators on one or both of the VHF inputs to avoid
overloading the amplifier
Outlet plates
The use of outlet plates is recommended to provide a professional standard of finish
to the distribution system PROception screened outlet plates are recommended for
use with this amplifier The diplexed TV and radio plate (proOUT12C) allows both TV
and radio equipment to be connected simultaneously to an outlet point Single outlets
(proOUT11C) may also be used and will allow either TV or radio equipment to be
used The system diagrams in Figs 1&2 show both types of plate in use
In Mode 2 a proOUT11C plate may also be used to provide the UHF return input
connection from the Sky receiver, as illustrated in the diagrams in Fig 2
Installation location and fixing
Choose a location for the amplifier which is dry and not subject to prolonged ambient
temperature conditions of less than -10 °C of more than + 40 °C Fix the unit to a
sound vertical surface such as a wall or equipment mounting board Ventilation gaps
of at least 50 mm should be left around the front and all sides of the unit More
clearance will be required around sides where cables are connected
Do not install the amplifier or its associated power unit where they may
become smothered with curtains or other soft furnishing fabrics. When
installing the amplifier and power unit in a roof space ensure that they will
not come into contact with thermal insulation material.
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