TX Digicast VLP-DR1 User manual

User Manual
Very Low Power
DAB/DMB Repeater
VLP-DR1
IMPORTANT!
Do not misconstrue any Information as our recommendation to use any product,
process, or equipment in conflict with any regulatory authority or patent. NO
REPRESENTATIONS OR WARRANTIES, EITHER EXPRESS OR IMPLIED, OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE OR OF ANY OTHER
NATURE ARE MADE WITH RESPECT TO ANY PRODUCT.
Ensure compliance with all applicable safety requirements when installing or using
this equipment, and operate in accordance with local laws governing the use of radio
transmission equipment.

Page 2
Index
Safety Warnings 3
Introduction 4
Features 4
Installation Instructions 5
Operation 8
Troubleshooting 9
Specifications 11

Page 3
1. Safety Warnings
IMPORTANT!
To reduce the risk of electrical shock, do not remove the cover, or any screws. NO user
serviceable parts inside; refer servicing to qualified personnel.
To reduce the risk of fire or electrical shock, do not expose this appliance to rain or moisture.
To reduce the risk of fire, always replace fuses with the same type and rating.
These instructions should be read in full before the Very Low Power DAB/DMB Repeater is
operated. The safety and operating instructions should be retained for future reference. All
warnings on the products, and in the operating instructions, should be adhered to. All
operation and user instructions should be followed. The equipment should not be used near
water.
It should be situated so that its location or position does not interfere with its proper
ventilation. And placed on, or fixed to, a flat surface away from heat sources.
The Very Low Power DAB/DMB Repeater should be connected to a power supply only of the
type described in the operating instructions or as marked on the unit. Precautions should be
taken so that the grounding or polarisation means of any appliance is not defeated. Power
supply cords should be routed so that they are not likely to be walked on or pinched by items
placed upon or against them, paying particular attention to cords and plugs and the point
where they exit from the Very Low Power DAB/DMB Repeater. The unit should be cleaned
only as recommended by the manufacturer. The power cord of the Very Low Power
DAB/DMB Repeater should be unplugged from the outlet when left unused for a long period
of time. Care should be taken so that objects do not fall and liquids are not spilled into the
enclosure through openings.
The Very Low Power DAB/DMB Repeater should be serviced by qualified service personnel
when: - The power supply cord or the plug has been damaged; or - Objects have fallen, or
liquid has been spilled into it; or - The product has been exposed to rain; or - The Very Low
Power DAB/DMB Repeater does not appear to operate normally or exhibits a marked
change in performance; or has been dropped, or damaged.
The user should not attempt to servicing beyond that which is described in the Operating
Instructions. All other servicing should be referred to qualified service personnel. There are
no user serviceable parts inside any part of the Very Low Power DAB/DMB Repeater.
Opening the product could interfere with the correct functioning of the electronic parts. Such
damage is not covered by any warranty.

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2. Introduction
As the consumer demand for DAB and DMB digital radio sets accelerates, there is a need
for effective demonstration of these radios in typical retail environments, especially in regard
to advanced features such as data services, EPG, advanced PAD features and so on. Often,
sales floors are less than ideal for these demonstrations due to the nature of the building
construction and their location.
An inexpensive repeater system has been designed to allow a very low power DAB signal to
be relayed to the immediate area of the retail store that wishes to demonstrate the features
of portable DAB and DMB.
The power level used is approximately one thousand times lower than a typical cellular
phone.
Average system installation should take a similar time to a typical satellite dish installation
and requires a similar level of competence.
3. Features
 Automatic gain stabilisation
 Bandpass filters prevent re-transmission of unwanted input signals
 Highly linear variable gain amplifier (30-50dB typical)
 BNC Output connector
 Supplied with AC Adaptor for indoor use
 Integral Helical Coil ("Rubber Duck") type transmitting antenna or external antenna
options
 Easy to install

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4. Installation Instructions
For installation, you will additionally require the following:
 Directional DAB receiving antenna (eg. 4-element Yagi type)
 Antenna mounting hardware
 CT100 (or better performance) coaxial cable
 Installation tools, as required
IMPORTANT:
 The Very Low Power DAB/DMB Repeater is designed to receive a DAB broadcast
signal, amplify it, and re-radiate it within a building. It is therefore essential that the
re-radiated (boosted) signal does not reach the external DAB Receiving Antenna,
otherwise feedback will occur and the repeater will not function correctly.
 Similarly, the coaxial cable run from the external DAB Receiving Antenna could pick
up the boosted signal, causing feedback.

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CT100 cable is highly recommended. It is vitally important that the cable used is very well
screened. CT100 cable is specified as it has a near 100% screen and is low loss (9dB/100m
@ 200MHz). Contract grade “Low loss TV Coax” without a foil screen must NOT be used.
The supplied ‘F’-Type screw on connector is suitable for CT100. Other types can be supplied
upon request. If you use other types of cable or connectors, please ensure they have a good
shielding characteristic.
Ensure that the input coaxial cable is not routed in close proximity to Very Low Power
DAB/DMB Repeater Antenna. Keep it as far away as possible.
If using the external Magnetic Mount Antenna option, ensure that input coaxial cable does
not cross over the output cable. Under no circumstance should they be tied together using
cable ties, or similar.
Where an existing distribution system provides a DAB signal from an external antenna, this
can often be used, otherwise a dedicated directional 4-Element DAB Receive Yagi antenna
(for example Antiference Model DAB2304, or similar) is recommended for reception.
The receiving antenna should be installed with the following points complied with:
 The external DAB Receive Antenna should be pointed at the most appropriate
transmitter site designed to serve the local area.
 The external DAB Receive Antenna should be mounted vertically with cable entering
from below
 The rear reflector element of the DAB Receive Antenna must be orientated towards
the shop floor area where the Very Low Power DAB/DMB Repeater is located.
 The external DAB Receive Antenna should be roof or wall mounted and as far as
possible from the area in which the Very Low Power DAB/DMB Repeater radiates.
 Try to use no more than 50m of CT100 (or better type) cable if possible.
WARNING!
IT IS ABSOLUTELY CRITICAL THAT THESE INSTRUCTIONS ARE FULLY COMPLIED
WITH, OR ELSE THE VERY LOW POWER DAB/DMB REPEATER WILL RECEIVE ITS
OWN OUTPUT (FEEDBACK) AND BECOME UNSTABLE. IT WILL AUTOMATICALLY
REDUCE ITS OUTPUT IN AN ATTEMPT TO CORRECT THE FEEDBACK OSCILLATION
AND TO PREVENT POSSIBLE INTERFERENCE RISK, BUT IT WILL NOT FUNCTION
PROPERLY UNTIL THE FEEDBACK PATH IS CORRECTED.

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The Very Low Power DAB/DMB Repeater’s output antenna is a simple Helical Coil (“Rubber
Duck”) type that facilitates wall mounting, ideally above the retail receiver demonstration
area. It has a reduced range compared to the external Magnetic Mount (whip) Antenna
option.
The latter ¼ wave whip is preferred when ceiling mounting is required, or when maximum
range must be achieved. It can, for example, be mounted vertically (even upside down, if
convenient) from a suitable steel beam, using the integral magnetic base. This permits
attachment to metal ceiling trunk/conduit or areas of steel cladding. Alternatively it can be
placed on a shelf or ceiling tile. If a magnetic surface cannot be found and there is any
danger of the antenna falling please ensure it is also secured using cable ties or other
additional method for safety.
Also ensure that there is a clear area around the whip so that the signal can clearly radiate
without excessive signal reflection.

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5. Operation
Check that the Very Low Power DAB/DMB Repeater is installed according to the site
requirements and the instructions given herein. Ensure that the external DAB Receiving
Antenna is connected to the ‘RF INPUT’ socket – and the Helical or ‘Whip’ is also connected
to the ‘ANTENNA’ socket.
Connect the mains AC Adaptor power source to the ‘DC INPUT’ socket.
The Very Low Power DAB/DMB Repeater is now operational.
‘STATUS’ LED Indication
Green RF Input signal strength is acceptable and output is
functioning as intended
Orange RF Input signal strength is too low
Red
RF Input signal strength is too high – or feedback is
present. Do not allow the unit to continue operating
under this condition.
The output of the Very Low Power DAB/DMB Repeater is normally supplied preset at the
factory for the number of multiplexes in use. So, for example, if it is required to repeat 4
multiplexes then it will be preset for 4mW output.

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6. Troubleshooting
The Very Low Power DAB/DMB Repeater features highly reliable technology and is unlikely
to fail in normal use.
The system reliability is critically related to the quality of the installation and, in particular, the
separation of the outdoor receiving antenna and the indoor transmitting antenna.
Fault Suggested solution
STATUS LED is not illuminated and
no output
Connect the supplied AC Adaptor.
Check the mains power supply to the AC Adaptor.
Only use the recommended power source, to avoid
damage not covered by warranty.
STATUS LED is red RF Input signal strength is too high. Try fitting a
coaxial attenuator to the RF input.
Feedback is present. Increase the isolation
between the signal area re-radiated (boosted) by
the Very Low Power DAB/DMB Repeater and the
DAB Receive Antenna. See instructions.
STATUS LED is orange RF Input signal strength is too low. Re-orientate the
DAB Receive Antenna to improve reception, or use
an antenna with a stronger gain specification.
As a last resort, an external aerial amplifier may be
added, but is not recommended (as this can
significantly increase the likelihood of feedback).

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6. Certificate of Compliance

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4. Specifications
Power 12V DC 300mA
RF Input Connector BNC socket (‘F’-type adaptor supplied)
RF Input Level -50 to -30dBm per MUX
Compliance ETSI 302 077
Bandwidth 8 to 60 MHz (Customer specified)
Output RF (BNC) 10mW Total maximum
Gain Over 50dB
Frequency Range 174 to 240 MHz (Other ranges upon request)
Accessories In-line attenuator, BNC adaptor, ‘F’-type connector
Specifications subject to change without notice.
TX Digicast
Unit 19
Richmond Crescent
Mossley
Lancashire
OL5 9LQ
Telephone [phone]
[e-mail]