H A N D B O O K
DT81
Arcam DT81 digital radio tuner
Using this handbook
This handbook has been designed to give you all the
information you need to install, connect, set up and use
the Arcam DT81 tuner. The CR-389 remote control handset
supplied with this equipment is also described.
Contents
Safety guidelines
2
2
2
Safety instructions
Safety compliance
Safety
Using this handbook
Safety
3
3
3
Safety guidelines are set out on the inside front cover of this
handbook.
Information on radio transmissions
Many of these items are common sense precautions, but for
your own safety, and to ensure that you do not damage the unit,
we strongly recommend that you read them.
Installation
4
4
4
4
5
5
Positioning the unit
Setting up the aerial
Connecting to other equipment
Additional rear panel functions
Connecting to a power supply
Radio interference
The DT81 digital radio tuner is an audio device containing
microprocessors and other digital electronics. It has
been designed to very high standards of electromagnetic
compatibility.
Using your tuner
6
6
6
6
6
6
7
7
7
7
7
Front panel controls
Searching for services
Programming a preset
Selecting a preset
Changing the display mode
A note on programme types
A note on secondary services
Dynamic label
If the equipment causes interference to radio/television
reception, which can be determined by switching the equipment
off and on, the following measures should be taken:
I Reorient the receiving antenna or route the antenna cable
of the receiver as far as possible from this appliance and
its cabling.
I Relocate the receiver with respect to this appliance.
I Connect the receiver and this appliance to different mains
outlets.
Signal quality meter
Engineering mode
Using the remote control
CR-389 remote control
8
8
If the problem persists contact your Arcam dealer or Arcam
Customer Support on +44 (0)1223 203203.
Troubleshooting
Technical specifications
Guarantee
9
10
11
11
EU countries
This product has been designed to comply with directive
89/336/EEC.
On line registration
Information on radio transmissions
For United Kingdom users the BBC publishes a booklet entitled
"Radio Transmitting Stations" which contains details of all BBC
transmitters in the UK together with other useful hints and tips.
This booklet can be obtained on request by sending a large
stamped addressed envelope to:
BBC Engineering Information Dept.
BBC Radio
201 Wood Lane
London W12 7TS
Telephone: 08700 100123
Internet:
(for general DAB information)
The Radio Authority publishes a booklet which contains details
of all independent radio stations. This booklet can be obtained
on request by sending a large stamped addressed envelope to:
Radio Authority
Holbrook House
14 Great Queen Street
Holborn
London WC2B 5DG
Telephone: 020 7430 2724
Fax:
020 7405 7062
Email:
Internet:
DT81
3
Installation
REMOTE
FM TUNER
INPUT
CONTROL
AUDIO OUTPUTS
230 V
DATA SERVICE
DIGITAL OUT
AERIAL
INPUT
IN
L
L
RDI
OUT
OUT
R
R
COAX
OPTICAL
POWER INLET
1
2
1
2 3 4
5
6
7
8
DT81 rear panel
1 Voltage indicator
2 Socket for IEC power inlet line
3 Remote control, in and out mini-jacks
4 FM tuner input
5 Audio output phono sockets, two pairs
6 Data Service on/off switch and RDI output
7 Digital audio output, coaxial and TOSLINK
8 Aerial input, BNC locking coaxial
Aerial input socket
Positioning the unit
The coaxial cable from the aerial should be fitted with a 50Ω
BNC plug. Connect this to the aerial socket on the back of this
tuner, turning to lock in place.
Always place the tuner on a level, firm surface.
Setting up the aerial
Your new Arcam tuner is capable of superb reception but only if
it is receiving a good quality transmission signal.
Connecting to other equipment
Interconnect cables
We recommend that a roof mounted aerial is used where
possible, to ensure the best performance. Use a Band III (multi-
element Yagi) array if you are a long way from a transmitter, or
use an omnidirectional or folded dipole aerial if you are close to
more than one transmitter. In the U.K. this should be mounted
with all elements vertical as the transmissions are vertically
polarised. Be sure to use a good quality coaxial cable such as
URM43, CT-100 or similar. For Band III use you can use either
50Ω or 75Ω cable provided it is good quality. Always use 50Ω
cable for L-band use.
Interconnecting cables are not supplied with this tuner. We
recommend high quality cables as inferior quality cables will
degrade the sound quality of your system. Please contact your
Arcam dealer for details of suitable cables.
Digital outputs
Optical and co-axial digital audio outputs are provided. These
can be connected to an external DAC (Digital to Analogue
Converter) in order to enhance the audio potential of this tuner.
They can also be used to connect this tuner to a digital
recording device (such as a CD-R or Minidisc recorder) for
direct recording.
If the signal is strong the supplied indoor aerial may be
sufficient. It should be hung on a wall with both wires fully
stretched out vertically. However there will be many areas
where one DAB ensemble (i.e. a group of stations transmitted
together) is strong and others are weak. An external aerial is
desirable in these cases in order to receive a higher number
of services. If the DAB services in your area are transmitted
on L-band (1.5GHz) then consult your dealer with regard to the
best aerial to use.
NOTE: The digital output data includes Serial Copy
Management System (SCMS) codes. This allows you to make
one generation of digital recording but further digital copies
will be prevented.
AM/FM tuner audio input
The audio output from a conventional tuner can be connected
here to save an input on the amplifier. When this tuner is
switched off or is set to bypass mode, this input is routed
straight to the audio output of this tuner.
NOTE: The supplied indoor aerial is suitable only for Band
III, not L-band. An aerial is not supplied in US or Canada.
There is a small aerial made by Bosch which is suitable for
L-Band and Band III and has been used with good results. The
Bosch part number is: F01DE00144
Remote control in/out
If you are using this tuner with an amplifier that also features a
remote bus (such as the Arcam Diva A85 or FMJ A22) you can
connect the REMOTE OUT of the amplifier to the REMOTE IN of
the tuner using a 3.5mm jack lead.
Robert Bosch Multimedia-System GmbH & Co. KG
Dept. MU/VMK
Postfach 77 77 77
D-31132 Hildesheim
This allows the tuner to be positioned out of sight while still
offering remote control as commands are passed through the
amplifier. It can also be used to route control signals for multi-
room use.
Telephone: +49 5121 49 4525
Fax:
+49 5121 49 2150
Email:
DT81
4
Additional rear panel functions
Data Service switch: DAB makes provision for providing
dedicated text and other data services in the multiplex
datastream.This switch can be set to the ‘in’ position (using the
end of a ballpoint pen) to prevent data services from appearing
among the available services on the tuner’s display.
RDI out: The Radio Data Interface (RDI) is an optical data
output that may allow future expansion to use certain data
services via an outboard device such as a personal computer.
The Data Service switch must be set to the ‘out’ position to
access the data streams from these services.
Connecting to a power supply
Wrong plug?
Check that the plug supplied with the unit fits your supply and
that your mains supply voltage agrees with the voltage setting
(115V or 230V) indicated on the rear panel of the unit 1.
If your mains supply voltage or mains plug is different,
consult your Arcam dealer or Arcam Customer Support on
+44 (0)1223 203203.
Mains lead
The appliance is normally supplied with a moulded mains plug
already fitted to the lead. If for any reason the plug needs to
be removed, it must be disposed of immediately and securely,
as it is a potential shock hazard when inserted into the mains
socket. Should you require a new mains lead, contact your
Arcam dealer.
Plugging in
Push the plug (IEC line socket) of the power cable supplied with
the unit into the POWER INLET socket 2 in the back of the unit.
Make sure it is pushed in firmly.
Put the plug on the other end of the cable into your power
supply socket and switch the socket on.
DT81
5
Using your tuner
DT81 DIGITAL RADIO TUNER
MENU
1-9
2-10
6-14
3-11
7-15
4-12
8-16
SELECT
5-13
SEARCH
STORE
STORE
DISPLAY
MODE
TUNER
POWER
1–8
9–16
BYPASS
Front panel controls
Programming a preset
First select the service you wish to assign to a preset. Now
press STORE 1–8 or STORE 9–16 and then briefly press the
appropriate preset button to store the service.
Power
Switches the unit on and off. When off the status LED shows
red. When the tuner is switched on the status LED shows
green.
It is not possible to assign secondary services to presets, only
primary ones, since secondary services are often broadcast on
a temporary basis and they may change from day to day.
Searching for services
When using the tuner for the first time we recommend that
you perform a search to find all available services in your
area. Once you have done this, you may wish to repeat a
search periodically to discover if any new ensembles (groups
of services) have gone on air. If you move to another area you
should also perform a new search.
Selecting a preset
To select presets 1 to 8, press and release the corresponding
button. To select presets 9 to 16, press and hold the
corresponding button for two seconds.
Changing the display mode
Selecting a search region
The bottom line of the display can be set to one of four modes:
Programme type (a brief label), Dynamic label (scrolling text),
Data rate (shows service data rate and stereo/mono mode)
and Signal quality meter (a bar graph). See page 7 for further
information.
Access the ‘Search Region’ menu by pressing the MENU button
three times. Use the rotary controller to select the world
region that best describes your location; the options are UK,
Canada or Rest of World. When the desired region is displayed,
press SELECT. The tuner takes a few seconds to reconfigure
its internal software before automatically switching out of the
Search Region menu. You should now perform a search for
available services.
Press DISPLAY MODE to cycle through the modes.
Compression mode
Press the MENU button once to access the compression menu.
From this, dynamic range compression (DRC) can be applied to
the audio signal within the tuner, provided the broadcaster has
made it available for that service. The amount of compression
is adjustable between ‘off’ and ‘5’ (the maximum amount).
To perform a search
Press SEARCH on the front panel, then SELECT when
prompted. A bar graph will show the progress of the search.
This can take up to three minutes depending on the search
region you have selected. The search can be cancelled at any
time by pressing any front panel button or rotating the rotary
controller.
To set the compression level, turn the rotary controller until the
required compression level is displayed and press SELECT. The
tuner leaves the compression menu and displays the service
name. ‘C1’ to ‘C5’ is shown in the top right corner of the
display, according to the compression level selected.
If no service is found after the search then either your aerial
is insufficient for your location or, you may be outside of the
covered area for DAB services. If this is the case contact either
your Arcam dealer or Arcam customer services.
To exit this menu without making any changes, press the MENU
button until the tuner reverts to displaying the service name.
Note that the selected level of compression is applied to all
services where compression data is made available by the
broadcaster. It is not possible to store different compression
levels for different stations.
Selecting a service
Turn the rotary controller to scroll through the available
services and choose the one you wish to listen to.
What happens next depends on the setting of the Selection
mode (see page 7). If set to ‘Auto’, the displayed service
is selected after 2.5 seconds; if set to ‘Manual’, the display
returns to the current service after five seconds unless SELECT
is pressed.
Service sort menu
Services can be sorted by name or by programme type. To
change between ‘sort by name’ and ‘sort by programme type’,
press the MENU button twice to access the Service Sort menu
and turn the rotary controller. Press SELECT to confirm the
setting: the tuner reverts to displaying the service name.
If >> is shown in the top right corner of the display when
a service is selected, a secondary service is also available.
Moving the rotary controller clockwise one more click will
display this secondary service: press SELECT to listen to it.
To exit this menu without making any changes, press the MENU
button until the tuner displays the service name.
DT81
6
Selection mode
Signal quality meter
Press the MENU button four times to access the Selection
Mode menu. This can be used to change the way services are
selected when scrolling with the rotary controller or when using
the < and > buttons on the remote control.
The signal quality meter is a simple bargraph which gives a
quick visual guide to reception quality. Technically, it is an
inverse measure of the Viterbi error rate, with zero errors at
full scale (all segments are lit) and 300 errors/second (with
all segments off). When reception is marginal, the number of
segments displayed becomes a very sensitive function of the
received signal strength and can be used to optimize the aerial
position.
To change between ‘AUTO’ and ‘MANUAL’, turn the rotary
controller and press SELECT to confirm the setting: the tuner
reverts to displaying the service name.
With the selection mode set to manual, the displayed service
name is selected by pressing the SELECT button on the tuner
or the BAND button on the remote control. When the selection
mode is set to auto, the displayed service is automatically
selected after 2.5 seconds.
Engineering mode
The DT81 digital radio tuner has two modes – in addition
to User Mode (in which the unit powers up) it also offers
an Engineering Mode that allows you to view technical
information about the currently selected service.
TUNER BYPASS switch
The front panel Tuner Bypass switch is used to switch between
this tuner’s AUDIO OUTPUT and the audio output of an FM tuner
attached to the FM TUNER INPUT sockets. The digital output
continues to output the audio signal from the currently selected
digital service on the DT81.
To access Engineering Mode, press SELECT and preset 8
simultaneously. ‘ENGINEERING MODE’ is briefly displayed. From
Engineering Mode you can return to User Mode by pressing
SELECT and preset 8 simultaneously again.
Once in Engineering Mode, each of the eight preset buttons
shows different technical information:
A note on Programme types
The Programme Type (PT) label is the short description
Preset 1: Ensemble frequency. This is the carrier frequency
of the currently selected ensemble.
displayed below the service name.
Preset 2: Service data rate. This is the data rate of the
current service in kilobits per second: the higher the number,
the better the sound quality.
Two different PT labels are transmitted: Static PT and
Dynamic PT. The static PT is the service ‘genre’ and does
not change. Radio 4’s static PT for example is ‘Current affairs’.
The dynamic PT reflects the current programme’s content (for
example, for Radio 4 typical dynamic PTs include ‘Drama’,
‘News’, etc.).
Preset 3: Service start and end CU numbers. The start
and end CU (Capacity Unit) numbers indicate the service’s
position within the ensemble.
When a service is selected, the dynamic PT is displayed; at
other times the static PT is shown. This means that Radio 4
will say ‘Current affairs’ while scrolling through services, then
may change to ‘Drama’ when that service is selected. The tuner
works this way because it cannot update dynamic PTs for a
multiplex to which it is not currently tuned.
Preset 4: Viterbi error/CRC failure count. The Viterbi rate
indicates the amount of error correction that is going on. Audio
decoding normally works transparently with Viterbi rates up
to about 200; above this, audible degradation of the signal
may be noticeable. The CRC (Cyclic Redundancy Check) failure
count indicates the amount of uncorrected errors. Any figure
above zero may mean audio disruption.
Note also that, for secondary services, the tuner displays the
parent’s static PT, since a dynamic PT would not be relevant.
Preset 5: Signal strength (AGC). A measure of raw RF
strength at the receiver front end.
A note on Secondary services
Preset 6: Transmitter ID information. This shows the IDs
(identities) of all the transmitters detected for the current
ensemble. DAB radio uses multiple transmitters for the same
signal and can add together for better results. If you turn the
rotor you can see how many transmitters are being picked up
and their respective field strengths on a scale of 1 to 7.
Primary services can have one or more secondary services
attached to them. These tend to be temporary; sporting
events like football matches for example may be broadcast
as secondary services. Services that have secondary services
attached to them are indicated by a >> symbol. Turning the
rotary selector clockwise will then reveal these services. The
secondary services themselves are indicated by a << symbol.
Preset 7: Audio mode. This shows that the selected
programme is being transmitted in Stereo, Joint Stereo or
Mono mode. (Joint stereo is an MPEG audio mode where the
data for one channel is sent along with data representing the
difference between the two channels. It allows a lower data rate
to be used, but is not as good quality as true stereo.)
You need to select a main service in order to see if there
are secondary services attached. The BBC is currently not
distinguishing between primary and secondary services, to
work with tuners that do not support secondary services. The
effect of this is to make those services appear twice in the list,
once as primary and once as secondary.
Preset 8: Transmission mode. This indicates which of four
possible methods of encoding/decoding transmissions is used
in the current service. This information may be useful to
engineers in diagnosing certain unusual problems.
Note that only primary services can be attached to a preset.
Dynamic label
This is a 128 character block of scrolling text used by most
broadcasters to display programme information (such as song
titles, useful phone numbers and website addresses).
DT81
7
Using the remote control
CR-389 Remote Control
FM/DAB
Ensure that DAB mode is selected using the
FM/DAB toggle button. The DAB LED above the
FM/DAB button is lit briefly when DAB is selected.
MENU
This button has the same function as the
MENU button on the front panel of the tuner.
DISP
TUNER
This button toggles the tuner’s display between bright,
FM DAB
dim and off.
Preset memory buttons
These buttons allow access to individual preset
stations. To select a preset press the corresponding
button. For presets 9 to 16, press and hold the
corresponding preset button for two seconds.
FM
MENU
2-10
DISP
3-11
7-15
DAB
TUNE buttons
These buttons enable you to scroll through the
available services. Depending on how the tuner is set
up the service is either selected automatically after
2.5 seconds or when you press the BAND button.
1-9
5-13
4-12
8-16
6-14
MODE
This button has the same function as
DISPLAY MODE on the front panel.
MODE
BAND
For more information on this feature see ‘Selection
mode’ on page 7.
SP1
SP2
BAND
ENTER
DISP
This button has the same function as SELECT on the
front panel.
SEL
Amplifier controls
These buttons offer basic control over Arcam
amplifiers, such as the A65, A75 or A85.
PHONO
AUX
DVD
CD
TUNER
TAPE
AV
VCR
AMPLIFIER
RPT
CD player controls
These buttons offer basic control over Arcam CD
players, such as the CD72 or CD92.
PROG
DISP
CD
CR-389
NOTE: Remember to install the two AAA batteries supplied
before trying to use your remote control.
Do not place anything in front of the tuner (where the IR
receiver is located), or the remote control may not work.
DT81
8
Troubleshooting
1. Display shows ‘Service not found’ when attempting to
Notes on data rate and sound quality
The tuner supports MPEG audio data rates up to 256 kb/s
which is the maximum rate as defined by the ETSI specification
for DAB radio.
select a service
This can happen when the tuner has an ensemble stored that is
no longer available. For example when the tuner is first shipped
it has the BBC ensemble stored, and if it is used in another
country then that ensemble will not be available. In this situation
one should perform a search.
Data rates transmitted are generally lower than this because
broadcasters prefer to include a high number of services within
the available bandwidth. Higher compression factors are used
to lower data rates, reducing audio quality.
Note that re-configuration of services within an ensemble is
handled without having to perform a search, so if services
are added or removed from the ensemble it is not necessary
to perform a search. Therefore ‘Service not found’ may also
appear when an attempt is made to select a service that has
been removed from the ensemble. Normally redundant services
are automatically removed from the list but occasionally they
are not. If this happens, simply select another active service
to remove redundant services fom the list of available services
and from any stored presets.
Most stereo services operate at 192kb/s at present, and this
has been found to give very high quality audio (though 256kb/s
is even better).
Some speech-based services use mono in order to reduce
the data rate and some apply higher compression as well. It
is also common to find that different services have different
audio quality even though they operate at the same data rate.
This is due to differences in the audio processing techniques
used in the transmission chain. Generally speaking, audio
is transmitted without applying dynamic range compression
(DRC) – unlike FM broadcasts. DAB uses a system whereby
the coefficients for DRC are transmitted separately, so that
the tuner can apply the compression itself. This is beneficial
because the listener can decide whether or not to apply DRC:
most hi-fi enthusiasts do not. However some DAB broadcasts
have some form of DRC applied directly to the audio and this
generally impairs audio quality.
The other situation when the tuner may fail to select a service
is when the signal strength is insufficient. When a service is not
selected it is possible to view the signal strength in Engineering
Mode (provided an attempt has been made to select a service
from the required ensemble) . Generally the meter needs to be
past the ‘E’ in ‘Strength’ for reliable reception.
We strongly recommend that an external aerial is used for the
best possible performance. If the signal strength is marginal
then an indoor aerial will only work some of the time, as the
signal quality is affected by weather and the time of day.
Note: There will be situations where some ensembles are
strong and others are weak. With a good aerial you may be
able to weakly pick up some ensembles from outside their
normal coverage range.
2. Display shows ‘No Signal’
This message is displayed if a signal at the required frequency
is missing. Note that it may take some time (about one minute)
to show the message. If you have removed the aerial and this
message appears, reconnect the aerial and reselect a service
to restore operation.
3. Display shows ‘No services stored’ at the end of the
search
This will happen when the signal strength is insufficient due to
either a poor aerial or lack of an available DAB signal.
4. Audio is lost and display shows ‘signal weak – muted’
This happens when the signal becomes weak. A better aerial
is required.
5. Audio is lost and display shows ‘Service ended’ or
‘Arcam DAB Tuner’
This occurs if the selected service is no longer broadcast – in
practice this will rarely happen. Select another active service.
6. Display shows ‘No service stored’ when a preset
button is pressed
This message is shown if a service has not been assigned to
a preset button or if that service has been removed from the
ensemble, even temporarily. If ensemble components are only
partially detected (due to weak signal strength) then the tuner
sometimes decides that a service has been removed and the
preset is deleted.
DT81
9
Technical specifications
DT81 digital radio tuner
Analogue audio ouput
Level
Output impedance
Minimum load
2.4V RMS at 0dB FS
<100Ω
600Ω
Bandwidth ( 0.5dB)
20Hz—20kHz
Digital audio ouput
Format
Sample rate
SPDIF coaxial & optical (TOSLINK)
48kHz
Output impedance (coaxial)
75Ω unbalanced
Radio Data Interface (RDI) ouput
Format
Modulation
Optical (TOSLINK)
Bi-phase (IEC-958)
RF input
Tuning range
174—240MHz (Band III)
1452—1492MHz (L-band)
Sensitivity
better than –91dBm, typically –95dBm
Decoding
Audio data rate (maximum)
Number of stored services (maximum)
256kbits/s MPEG layer II, protection level 3
128
Aerial
Impedance
50Ω nominal in operational frequency range
Connector
BNC
General
Supply voltage
Power consumption
Size W x D x H
Weight net
115V or 230V AC
30VA operational, 5VA standby
435 x 320 x 83mm
4.6kg
Weight packed
Supplied accessories
6.1kg
Mains lead
CR-389 remote control handset and 2 x AAA batteries
Wire dipole aerial (Band III)
E&OE
Continual improvement policy
Arcam has a policy of continual improvement for its products.
This means that designs and specifications are subject to
NOTE: All specification values are typical unless otherwise
stated.
change without notice.
DT81
10
Guarantee
It should be sent carriage prepaid by a reputable carrier -–
NOT by post. No responsibility can be accepted for the unit
whilst in transit to the dealer or distributor and customers are
therefore advised to insure the unit against loss or damage
whilst in transit.
Worldwide Guarantee
This entitles you to have the unit repaired free of charge, during
the first two years after purchase, at any authorised Arcam
distributor provided that it was originally purchased from
an authorised Arcam dealer or distributor. The manufacturer
can take no responsibility for defects arising from accident,
misuse, abuse, wear and tear, neglect or through unauthorised
adjustment and/or repair, neither can they accept responsibility
for damage or loss occurring during transit to or from the
person claiming under the guarantee.
For further details contact Arcam at:
Arcam Customer Support Department,
Pembroke Avenue, Waterbeach, CAMBRIDGE
CB5 9PB, England.
Telephone: +44 (0)1223 203203
Fax: +44 (0)1223 863384
Email: [email protected]
The warranty covers:
Parts and labour costs for two years from the purchase date.
After two years you must pay for both parts and labour costs.
The warranty does not cover transportation costs at any time.
Problems!
Always contact your dealer in the first instance.
Claims under guarantee
If your dealer is unable to answer any query regarding this
or any other Arcam product please contact Arcam Customer
Support on +44 (0) 1223 203203 or write to us at the above
address and we will do our best to help you.
This equipment should be packed in the original packing
and returned to the dealer from whom it was purchased, or
failing this, directly to the Arcam distributor in the country of
residence.
On-line registration
You can register your Arcam product on line at:
DT81
11
PEMBROKE AVENUE, WATERBEACH, CAMBRIDGE CB5 9PB, ENGLAND
Issue 1
SH102E
|