Pace MSS100 Series User manual

MSS100.....
Satellite Receiver
Service
Manual
PACE
“8
7

THIS MANUAL COVERS THE FOLLOWING RECEIVERS:
MSS 100-1, MSS 138-G
PLEASE READ THE IMPORTANT NOTES ON PAGE 2.
CONTENTS
IMPORTANT NOTES...
OUTLINE SPECIFICATION
PIN DESIGNATIONS FOR
CONTROLS ..
MENU TREE ...
INSTALLATION
UHF TUNING
FORCING A PLAIN BACKGROUND FOR MENUS
SETTING UP THE RECEIVER FOR THE ATTACHED DISH AND LNB(S)
Reaching the Input Menu
Changing the offset
Turning on/off power to the LNB
Setting the dish type .
Setting the polariser ty
Setting the LNB type
Setting the LNB band(s)
Changing the “Variable” setting
Saving your settings ..
DOWNLOADING
RESETTING THE PIN
WORKING WITH CHIP COMPONENTS
GAINING ACCESS TO THE UNIT .
CIRCUIT DESCRIPTION...
MAIN BLOCK DIAGRAM
TUNER AND VIDEO PROCESSING
UHF MODULATOR .....
SWITCH MODE POWER SUPPLY
CONTROL C:RCUITRY AND DISPLAY
DEMODULATION AND DE-EMPHASIS __..
PERIFERAL COMPONENTS ANO CONTROL LINES ..
AUDIO BASEBAND AND SIGNAL ROUTING ....
CIRCUIT DESCRIPTION (FOR RECEIVERS WITHOUT AN INTEGRAL DECODER)
FAULT FINDING...
Checks on the Card Reader
Pin Numbering for Card Rea
GRID REFS - IDENT DIAGRAMS FOR MAIN PCB
GRID REFS - MAIN CIRCUIT (DIAGRAM ON SEPARATE SHEET) ..
‘SPARES - ELECTRICAL PARTS LIST FOR MAIN BOARD
SPARES - MECHANICAL PARTS LIST ..
DIFFERENCES BETWEEN THE IRD AND NON-IRD MODELS
Deleted components
Additional or changed components
Mechanical parts list - difference
POCKET FOR SEPARATE CIRCUIT DIAGRAMS AND VIDEOCRYPT INFORMATION ......41

Important Notes
The MSS 100 series of receivers have one main PCB
which contains the majority of the components. Some
units also have a small microprocessor extension PCB.
The main PCB is currently at Revision A1. The PCB's part
number is marked on the component side of the PCB.
This number can be read on the component ident
diagram in this manual, where revision A1 is denoted
by the characters 101 at the end of the part number.
The parts lists and circuit diagrams in this manual
include information from all Engineering Change
Orders (ECOs) up to and including ECO $001016 and all
Production Change Orders (PCOs) up to and including
PCO $000458, provided that these ECOs and PCOs had
an effectivity date on or before 28.06.95. Further
changes will be given in technical bulletins.
If you need to find out the software version number of
the receiver, you can display the Download Menu (see
page 12) and then press the STORE key to display the
second Download screen, which shows the software
version number.
CIRCUIT DIAGRAMS
Asheet containing the main circuit diagram is in the
pocket inside the rear cover of this manual.
VIDEOCRYPT CIRCUIT DESCRIPTIONS AND
DIAGRAMS.
The MSS 109-1 contains VideoCrypt circuitry. For copy-
right reasons, the circuit description and diagrams for
this have been printed on special paper on a separate
sheet, part of which has been overprinted with broad
diagonal stripes to prevent photocopying. Each of
these sheets has a unique, traceable serial number. As
the card reader is intimately linked with the VideoCrypt
circuitry, the description of the card reader circuitry is
also given on this sheet, which can be found in the
pocket at the rear of the manual.
HAND MODIFICATIONS
Hand modification to stabilise voltage
regulators (ECO 001051)
Some 12 V voltage regulators oscillate in a hot ambient
temperature. To alleviate this problem a 10 uF 5mm
20% 105c R/EL capacitor is fitted to U3 as shown in the
diagram right.
10 uF Smm 20% 105¢ P/EL CAP 5x 11 855-1065751
Hand modification to stop PANDA de-emphasis
locking up (ECO 001048)
This modification prevents PANDA de-emphasis in U500
from locking up during power up.
Asignal diode-BAT85/BAT 42 is added between pin 2
of U500 and LK502 (cathode). A second signal diode,
BAT 85/BAT 42 is added between pin 54 of U500 and
LK502 (cathode). Shown in the diagram right.
Signal diode-bat 85/bat 42 120-0008501
Capacitor
MSS 100 Series Satelliee Receiver
ENGLISH

Hand modification to insert a 2 amp quick blow fuse
(ECO 001048)
This modification ensures the receiver meets BEAB require-
ments.
A 27uH 10% Axial Inductor is attached to a 2A Axial
antisurge fuse on L7, as shown in the diagram right.
The label “T2A fuse” is attached as shown in the diagram
right.
27UH 10% Axial inductor 0805 130-0270601
Fuse-2A Axial antisurge 201-7410020
“A" Fuse Label T2A fuse MSS 100 PCB 299-1000210
Hand modification to meet BEAB requirements
(ECO 001048)
The label “F1AL/250v” is attached as shown in the diagram
right.
*A* Fuse Label F1AL/250v MSS 100 PCB 299-1000200
Hand modification to the VideoCrypt circuit (ECO 001059)
This modification adds a capacitor to decouple the bottom reference
voltage.
A decoupling capacitor is added across pin 10 and pin 12 of U300 as
shown in the diagram right.
400nF 50v 20% 5mm M/LAYER CAP TR 157-1045751
M/Layer
Capacitor
Pin 10 Pin 12
Hand
modification
to
prevent
oscillation
of
the
LNB
330PF
caparitor
supply
(ECO 001059)
|
between
collector
This
modification
prevents
the
LNB
supply
from
oscillating
and
base
of
2
when
set
to
the
horizontal
polarity,
due
to variations
in
the
transistor
gain
bandwidth.
A
capacitor
is
connected
between
the
base
and
the
collector
of
Q2
as
shown
in
the
diagram
right.
380 pF 50v 10% CER CAP COG 0805 TR 950-3315601
Important Notes

Outline
Specification
GENERAL
Number of Programmes
Control buttons
UHF Modulator
Operating Voltage
Power Consumption
Dimensions
Weight
CONNECTORS
TV
VIDEO RECORDER
DECODER
R &L (audio out)
MAINS INPUT
AERIAL
WwW
LNB
TUNER
Receiving Frequency Range
Polarity Switching
LNB Tone Switching
Input Impedance
LF
\.F, Bandwidth
Input Level
Image Rejection
Static Threshold
Energy Dispersion Removal
SCART CONNECTORS
Video Output Level
Video Output Impedance
Video Frequency Range
Video De-emphasis (PAL)
Baseband Output Level
Baseband Frequency Range
Baseband De-emphasis
Audio Frequency Range
Audio Output Level
250
Standby, Programme Up/Down buttons
CCIR
PAL
System
|
(System
G
in
MSS
138-G),
Ch.
21
to
69,
preset
to
Ch.
38
180
- 240
V
AC,
50
Hz
18 W (max.) optional 10 W typical in low-power standby.
H = 75 mm, W = 260 mm, D = 260 mm approx.
1.9 kg (typical, when packed)
SCART
(RGB
looped
from
decoder
SCART
only
and
CVBS)
SCART
(CVBS)
SCART
(Baseband
Output,
Audio/Video
Input/Output,
RGB
in)
Phono
2-pin reversible
IEC female
IEC male
Single F type (MSS100-1)/Dual F type(MSS138-G)
700 -— 2150 MHz
Vertical: 12.0 - 14.0 V, Horizontal: 17.0 - 20.0 V
at 0 - 400 mA with short circuit protection
Amplitude: 0.6 V +0.2 V, Frequency: 22 kHz +2 kHz
75Q
479.5 MHz
27 MHz fixed (MSS100-1)
15 MHz/27 MHz software selectable (MSS138-G)
-60 dBm to -30 dBm
40 dB (typically)
6 dB (typically)
35 dB (min.)
1 V p-p (£2 dB) into 75 Q load.
759
50 Hz - 4.8 MHz (3B)
to CCIR 405.1 (625 lines)
1 V p-p (£2 dB) into 75Q load.
30 Hz - 10.5 MHz (+3 dB) (Flat)
PAL/Clamped/Flat, software selectable
30 Hz- 12 kHz
500 mV RMS into 10k Q
OPERATING/STORAGE CONDITIONS
Operating Temperature Range
Storage Temperature Range
AUDIO
Audio Bandwidth
Audio De-emphasis
Juning Frequency Range
Modes
5-40°C
20 - +50°C
130, 180, 200, 280, 380, 500 or 600 kHz
PANDA 1, 50 ps, 75 ys or J17
5.00 - 9.00 MHz in 10 kHz steps, left and right frequencies
are independently tunable.
Mono 1 to 9 and Stereo A to D.
Due
to
continued
product
improvement,
this
specification
is
subject
to
change
without
prior
notice.
-
yl
MSS 100 Series Satellitz Receiver
ENGLISH

AUDIO
KU-Band preset audio modes
Mode
Stereo A
Stereo B
Stereo C
Stereo D
Mono 1
Mono 2
Mono 3
Mono 4
Mono 5
Mono 6
Mono 7
Mono 8
Mono 9
Frequency
7.02 & 7.20 MHz
7.38 & 7.56 MHz
7.74 & 7.92 MHz
8.10 & 8.28 MHz
6.50 MHz
7.02 MHz
7.20 MHz
7.38 MHz
7.56 MHz
7.74 MHz
7.92 MHz
8.10 MHz
8.28 MHz
De-emphasis Bandwidth
PANDA 1
PANDA 1
PANDA 1
PANDA 1
50 us
PANDA 1
PANDA 1
PANDA 1
PANDA 1
PANDA 1
PANDA 1
PANDA 1
PANDA 1
130 kHz
130 kHz
130 kHz
130 kHz
200 kHz
130 kHz
130 kHz
130 kHz
130 kHz
130 kHz
130 kHz
130 kHz
130 kHz
PIN DESIGNATIONS FOR SCART CONNECTORS
20
000000006
21 30G000G000
Socket Viewed from Rear Panel
|
Pin TV SCART
R Audie Sut
Not connacted
L Audio ut
Audio G-ound
Not connected
Blue Out
AV Status Out
9 Green Ground
10 Not connected
1 Green Out
12 Not connected
13 Red Ground
14 Ground
1
2
3
4
5 Blue Ground
6
7
8
15 Red Out
16 —- RGB Status Out
17 Video Ground
18 Ground
19 Video Out
20 Not connected
21. Ground (Casing)
Pin VCR SCART
R Audio Out
R Audio In
L Audio Out
Audio Ground
L Audio In
Not connected
VCR Status In
Ground
10 Serial Data I/O port
1
Zi
3
4
5 Ground
6
7
8
9
1 Not connected
12 Serial Data I/O port
13 Ground
14 Ground
15 Not connected
16 Not connected
17 Video.Ground
18 Ground
19 Video Out
20 Video In
21 Ground (Casing)
Pin
ONAN EWHN
10
12
13
14
15
16
17
18
19
20
21
DECODER SCART
R Audio Out
R Audio In
L Audio Out
Audio Ground
Blue Ground
L Audio In
Blue In
Ext. Decoder Status In
Green Ground
Not connected
Green In
Serial Data 1/0 Port
Red Ground
Ground
Red In
RGB Status In
Video Ground
Ground
Baseband Video Out
Video In
Ground (Casing)
Outline Specification

Controls
HANDSET OVERVIEW
OD 10 put the receiver into or
MM To switch between satellite TV,
take it out of standby.
terrestrial TV or your video
recorder (if your receiver, TV and
video recorder are connected by
‘SCART leads).
© _ Number keys. To select
to programmes; to move
between menus (sometimes
to change menu values).
To select an external audio/
video (AV) source.
2]
tr F (function) key — used with
the other keys to give “short-
cut” methods for certain
functions (e.g. LOCK).
"ne F "is displayed on screen
when you press this key
(indicating that another key
must be pressed for the
shortcut to work).
To recall the last programme.
To select menu options (move
within a menu).
To step through programmes in
normal viewing mode; to change
values in menus.
8 @iv4 B | oz
eM
To
display
the
Main
Menu
on
.
screen;
to
move
beck
up
the
To
display
programme
menus
to
previous
menus.
information.
GED
7
select
satellite
radio
To
store
changes
and
leave
NORM
MUTE
programmes.
menu
to
return
to
a
satellite
VOL
programme.
be
Ww
To
select
favourite
categories.
To
select
menu
options
(move
SHAPE A
within a menu).
meme To leave menu without storing
changes and return to a satellite
programme.
oo
oerrect—
7
To
mute
the
sound,
[ ¥— Volume (rocker) key (shown
in the manual as VOL A or
VOLY.
ELD These keys have no function.
The handset operates the receiver using a
series of lists (menus). Each menu comprises
a range of numbered options, grouped
according to the job they perform.
When an operation is described in this
manual, it is often given pictorially and as a
written instruction, as shown below which
means: On your satellite receiver handset,
press the MENU key, then press the 5 key,
then press the 2 key.
Press MENU, 5, 2
or
@® 0 e>
The arrow (> ) indicates
the result of your actions.
MSS 100 Series Satelliy Receiver
ENGLISH

Menu Tree
* = absent for receivers with integral
VideoCrypt decoder.
+ =absent for receivers with a single
LNB input.
§ =the presence of these options in
the menu depends on settings made
at the Input Menu.
Parental Lock
Main Menu
Parental Lock
VCR Timer
‘Swap Programme
‘Move Programme
Set Up Programme.
Installation
Lock Programme
Lock Menus
Change PIN
VCR Timer Summary
VOX = 4-THU 16:45
Not Set
Not Set
Not Set
Not Set
Not Set
Not Set
Not Set
Swap QVC
and QVC
Prog 12
Prog 12
@uaan on
Timer 1
TUE 10:18:25
Move QVC
to ave
Prog 12
Prog 12
Prog 35
16:48
17:30
4THU
Daily
Prog 4
MOVIE CHAN
4 Frequency = 11.478
2 Polarisation v
3 Input t 1
4 Bond § Low
5 Tone § off
6 LF. Bandwidtht 27MHz
7 Decoder Output PAL
8 AV Source Auto
°
7 Name — MOVIE CHAN’
2 Audio Stereo A
8 Frequency — L: 7.02
4 R:7.20
5 De-emphasis Panda
Bandwidth 190kHz
7 Category Films
8 Skip off
9 Satellite 4
9 More...
Use the number keys to move down the
menu tree and the MENU key to move
back up it. To return to normal viewing
mode, press STORE (to store any changes)
or NORM (without storing any changes).
Installation
Input
UHF Tuning
Power-on Options
Clock
Download ohana
UHF Tuning
oF AFC
Offset
Power On
i Dish Steerable
Poleriser Magn/Mech
LNB Single
LNB Band 9.750 FSS A
Input 1
Channel
Fine Tune
AFC
i More...
Steerable
Polariser Magn/Mech.
une Single
LNB 8.750 FSS A
More...
Menu Tree
Power-on options
4. Low-power Standby
2 Programme
3 Volume
‘Vok MIMNENLHIHMIU....
Clock
Day Hrs Min
SUN 10:15
Download
1 Power OFF the nc eiver to
be programmed
2 Connect a scarteaid
between the VC; escart
‘on each rece
Press STORE to coti nue or
NORM to exit.

Installation
UHF TUNING
Note
You can ignore this section if the satellite receiver
and TV (and video recorder) are connected by SCART
leads.
If the satellite receiver is connected to the TV (and video
recorder) by coaxial leads then you must perform UHF
tuning.
Notes
You may connect the satellite receiver by both SCART
and coaxial leads. As long as SCART leads have been
used to connect your satellite receiver, TV and video
recorder you do not need to perform UHF tuning.
It is important that the UHF channel chosen for
satellite TV is not used for the video recorder and is
free of any other broadcasting.
Tuning the TV (and video recorder) to the
satellite receiver
The satellite receiver has been factory set to UHF chan-
nel 38 (UHF frequency 607.25 MHz). To tune the TV to
this channel proceed as follows:
»> Press the number key(s) on the TV handset that you
want to use for satellite TV.
>> On the satellite receiver handset press F, 5.
The red light on the front panel of the satellite receiver
should flash.
tf the TV channel chosen corresponds to UHF channel 38
then you will see the satellite receiver UHF Tuning Menu
onscreen. if you do not see this menu then you must
tune the TV in accordance with the manufacturer's
instructions until a good quality picture of the UHF
Tuning Menu is visible.
>> Press NORM to renove the UHF Tuning Menu from
the screen.
>> You should now see a satellite TV programme.
>> Set your video recorder to the same UHF channel.
Tuning your satellite receiver to a UHF
channel
>> Select the number key(s) on your handset that you
want to use for satellite TV.
>> Set the UHF channel for this handset key to one that
is free of any other broadcasts, for example UHF
channel 46.
>> Press F, 5 on the satellite receiver handset.
The receiver's UHF Tuning Menu is now selected
(although you cannot see it yet). The red light on the
front panel should flash.
>> Press the two number keys on the satellite receiver
handset that correspond to the chosen UHF channel
number, in this example 4, 6.
You should see the UHF Tuning Menu on the TV screen.
>> Press STORE to save this setting.
>» Set the video recorder to the same UHF channel.
Note
If having completed the tuning, you see a UHF
Tuning Menu but no picture, check the Band
setting at the Set Up Programme Menu.
UHF Tuning
Channel
Fine Tune
Fine tuning
To get the sharpest picture, you may wish to fire tune at
the UHF Tuning Menu.
>> Press & or ¥ to select the Fine Tune option.
>) Press < or » to get the sharpest picture.
>> Press STORE.
You can fine tune between -3 and +4. If you prss > at
+4, the channel increases by one and Fine Tune
becomes -3.
MSS 100 Series Satelit: Receiver
ENGLISH

FORCING A PLAIN BACKGROUND FOR MENUS
Sometimes, when there is a scrambled or distorted
picture on the screen, a menu may be difficult to read.
Force a plain background as follows:
>) Press TV/SAT.
>> Press TV/SAT again to remove the plain background.
SETTING UP THE RECEIVER FOR THE
ATTACHED DISH AND LNB(S)
Reaching the Input Menu
>» To display the Input Menu press MENU, 6, 1.
The input Menu should appear superimposed on the
satellite programme. It could be that until you adjust
certain settings at this menu, the background picture
remains very distorted, making the text difficult to read.
If this is the case, you can press the TV/SAT key on your
handset to force a plain background for the menu.
Note
Ina non-IRD receiver, display the Input 2 Menu, by
pressing 0 at the Input 1 Menu.
Important - the LNB Band.
Before using the receiver it is very important to check
that the “LNB Band” option (or “Low Band” and “High
Band” options) at the relevant Input Menu is set to
correspond with the LNB on the dish attached to that
input. If it is nox, then there can be problems (see below).
The LNB type fe: input 1 (and Input 2 in non-IRD receiv-
ers) is preset at “he factory as 9.750 FSS A (preset for LNBs
with a local osc: ‘ator whose frequency is 9.750 GHz).
The following information assumes that your dish
antenna and LN3 have been installed and that the lead
from the LNB is connected to Input 1 of your receiver.
aD >
distorted
background
plain coloured
background
7 F-AFC Input 1
Offset AFC
Power On
00> Dish Steerable
Poleriser Magn/Mech
LNB Single
LNB Band FSS A 9.750
2 More...
Orly available in 0
non-IRD receivers.
Ov
"@ F-AFC Input 2
Offset
Power
Dish Steerable
Polariser Magn/Mech
LNB Single
LNB Band FSS A 9.750
More...
What can happen if an LNB is set incorrectly
If an LNB setting does not correspond with the attached
LNB, there can be problems.
if you set “FSS B” at the Input Menu and the LNB is not
suitable for “FSS B” (or, conversely, you have attached an
“FSS B" LNB, but set a different value at the menu) then
the receiver tunes to a different frequency, so that you
see a different programme or no programme at all.
In other cases the receiver does not tune into a different
frequency (i.e. the same programme remains on the
screen) but the frequency displayed at the Set Up
Programme Menu may not be correct.
If you are attaching this receiver to an existing
satellite dish
You can check if it is set correctly as follows:
>» Look at the programme list and key in the
programme number that corresponds to Sky News
(frequency: 11.377 GHz); the programme Sky News
should be visible.
>> If you see CNN on the screen, display the Input Menu
and change the LNB Band option from FSS A 9.7 50 to
FSS B 10.000 - see page 20.
>» If you see GALAVISION, display the Input Menuand
change the LNB Band option from FSS B 10.000to
FSS A 9.750 - see page 20.
Installation

Changing the offset
You cannot adjust the offset until you have pointed the
dish at the satellite and can see some programmes.
The receiver has been factory-preset for automatic offset
(AFC). For a fixed dish, AFC should give a good picture
with few or no speckles. You should not need to alter
this unless you are trying to receive a very weak signal
with a speckled picture.
For a steerable dish, we recommend that you switch off
AFC.
>> Press F to switch off the AFC.
>> Press < or to set the offset manually between -15
and +15 to give the best picture, with an even mix of
black and white speckles.
>> Press STORE to save.
>> If a non-IRD receiver also has a dish connected to
Input 2, select a programme being received at Input
2. Display the Input 2 Menu and change the offset as
described above.
Turning on/off the power to the LNB
The receiver should provide power to the LNB except in
certain communal dish installations (in which case the
LNB must not receive power from the receiver). If you
are connecting your receiver to a communal dish instal-
lation, consult the installer for advice on which setting
you should choose.
Setting What is powered
Off LNB never powered from the receiver
On power to the LNB from the receiver
(if “On” is set at both Input Menus,
power goes only to the LNB which is
receiving the current programme).
Setting the dish type
The Dish option allows you to inform the receiver that
you have connected a steerable dish or a fixed dish.
>> Press < or to set “Steerable” or “Fixed” as
appropriate.
When “Steerable” is selected, the Polariser option
appears in the Input Menu.
Setting the polariser type
If you have not attached a dish positioner to the re-
ceiver, or have attached a positioner that does not
contain polariser control circuitry, the factory setting of
“Volt” is correct. Do not change this setting.
If you have attached a dish positioner that contains
polariser control circuitry, you must change the setting at
the Polariser option.
>> Press < or ® to set Magn/Mech.
If you change the Polariser option you must check that
the LNB option has the correct setting.
LNBs that have an electromagnetic or mechanical
polariser, are an advantage for steerable dishes as they
allow you to make adjustments to give the best picture
for each programme.
“7 F-AFC Input 1
4
2
3
4
5
6
°
Input 4
Offset
Power
Dish Steerable
Polariser Volt
LNB Single
LNB Band FSS A 9.750
Offset
Power On
Dish Steerable
Polariser Volt
LNB Single
LNB Band FSS A 9.750
More... More...
Steerable
Polariser Volt
NB Single
LNB Band FSS A 9.750
MSS 100 Series SatelliteF€eceiver
ENGLISH

Setting the LNB type
The LNB option must be set to correspond with the type
of LNB on your dish.
>) Press < or» to set the required value (see table
right).
If Multi Band or Universal is selected, the next option in
the menu (“LNB Band”) changes to become two options,
Low Band and High Band.
You must then set the “LNB Band” or “Low Band” and
“High Band” options to correspond with the LNB (see
below).
Setting Usage
Single If the LNB is single-band.
Universal If the dish has a universal LNB. This is
a specific type of multi-band tone-
switching LNB with specific band
settings (see table below) anda
voltage-switching polariser.
Multi Band Tone
If the LNB is multi-band and uses a
tone to switch between bands.
Notes
if “Multi Band Tone” or “Universal” is set then the
“Tone” option disappears from the Set Up
Programme Menu.
If “Multi Band Tone”, “Multi Band Volt" or “Univer-
sal” is selected ,then a “Band” option appears in the
Set Up Programme Menu.
Multi Band Volt
If the LNB is multi-band and uses
voltage to switch between bands.
Setting the LNB Band(s)
>> For a single-band LNB, press < or » to select one of
the LNB bands shown right or choose the setting
"Variable" (see below).
The numbers in the LNB Band names are the frequencies
(in GHz) of the LNB’s local oscillator. The second column
shows the frequency range over which you should tune
at the Set Up Programme Menu. We do not recommend
that you tune outside these ranges, as performance
cannot then be guaranteed.
>> For a multi-band LNB, select the Low Band and High LNB Band Freq. Range(GHz) Typical Satellites
Band options in turn and press 4 or ® to set the FSS A 9.750 10.700- 11.800 Astra 1A, 1B, 1C, 1D/
correct value for each band. The following options Intelsat/ Eutelsat
arerevallable: FSSB 10.000 10.920-11.700 Astra 1A, 1B, 10
Intelsat/ Eutelsat
Low Band FSS A 9.750/ FSS B 10.000/ DBS 10.750 11.700- 12.500 TDF/ TV-Sav/
C-Band 5.150 Hispasat
High Band md Meisohin 11.475) T-COM 11.475 12.500- 12.750 Telecom 24, 2B, 1C
ade eee C-Band 5.150 3.700- 4.200 —Asiasat
BSS 10.600 11.700- 12.500 Astra
Note
If the LNB option is set to Universal, you cannot
change the Low Band and High Band settings.
Changing the “Variable” setting
>> Select “Var.” (the number next to it flashes). Use the
number keys to key in the LNB's local oscillator
frequency (in the range 9.050 to 13.000 GHz).
Saving your settings
You do not need to press STORE after changing each
setting. Instead make all the changes you desire at the
menu, then press STORE to save all the settings.
Installation

DOWNLOADING
You use this feature to “program” another receiver of
the same type. During the download, all of the infor-
mation stored in the first receiver's internal memory is
transferred to the second receiver. This includes all the
settings which you have made and stored at the menus,
except the clock setting and any timers you have set up.
Note
When downloading, you must follow the on-screen
instructions exactly, otherwise errors may occur.
With a satellite TV picture displayed from the receiver
you are downloading from:
)> At the receiver you are downloading from, press
MENU, 6, 5, to display the Download Menu.
)») Turn off the power to the receiver you want to
download to.
>)» Connect a SCART lead between the VCR SCART
connector on the rear panel of each receiver.
> Press STORE.
Note
The number on the screen is the software version
number.
»» Turn on the power to the receiver you want to
download to.
Note
Up to this stage, you can stop the download by
pressing the NORM key. If you continue beyond this
step, you cannot stop the download.
> Press STORE.
During download “global” information is transferred
first, then all the programme information. Messages
appear on the screen to tell you which programme is
currently being transferred. Download takes about 15
seconds.
»> When the message “Download Complete” appears,
disconnect the receiver you have downloaded to.
Press STORE to return to the Installation Menu if
you wish to download to another receiver,
otherwise press NORM to return to a satellite
programme.
If the download fails for any reason, the message
“Download Error” appears.
RI
TTING THE PIN
The factory-set PIN is 1234.
If you have a PIN and do not know what it is, you can
reset the PIN to its factory value as follows:
At the wall socket, disconnect the receiver from the
mains supply. Hold down the © button on the top
cover while you reconnect the receiver at the wall
socket. You need to hold down the © button for several
seconds.
When the PIN is reset, the following also occur: any
locked programmes or menus become unlocked and the
clock and any timers set up are no longer set.
Download
11 Power OFF the receiver to
be programmed
2 Connect a Scart lead
between the VCR Scart
‘on each receiver
Press STORE to continue or
NORM to exit.
Download
Power ON the receiver to
be programmed
00000000
Download
Ready to download
Press STORE to continue or
NORM to exit.
Download
Downloading Prog.
Download
‘Download Complete
Press STORE to continue
‘or NORM to exit.
Download
Download Error
Press STORE to continue
‘or NORM to exit.
MSS 100 Series Satellite Receiver

Working
with
Chip
Components
ELECTROSTATIC SENSITIVE (ES) DEVICES
Many
semiconductor
devices,
such
as
integrated
circuits
and
field
effect
transistors,
can
easily
be
damaged
by
static
electricity.
The
following
precautions
should
be
observed
when
ES
devices
are
being
handled.
*
Always
use
a
grounded
tip
soldering
iron
and
anti-static
type
solder
removal
devices.
*
Before
handling
a
device,
discharge
any
electrostatic
charge
on
your
body
by touching
a
known
earth
point
-
preferably
use
an
earthed
bench
mat
or
ground
mat
together
with
a
wrist
strap.
*
Do
not
remove
an
ES
device
from
its
protective
packing
until
you
are
ready
to
fit
it.
Touch
the
protective
material
to
the
chassis
or
the
assembly
in
which
the
ES
device
is
to be
in-
stalled,
before
removing
the
device
from
its packing.
Soldering
GENERAL
PRECAUTIONS
WHEN
HANDLING
CHIPS
aii
Do
not
handle
chips
with
your
bare
hands
as
this
causes
oxidation
on
the
chip’s
terminals
which
leads
to
poor
soldering.
Do
not
store
the
chips
in
any
of
the
following
,
as
oxidation
occur
s
and
capacitance
and
resistance
are
affected
i.e.
areas
with
sulphur
or
Sonia
waeue
chlorine
gas;
direct
sunlight
and
areas
of
high
temperature
and/or
iron
high
humidity.
Rough
handling
of
circuit
boards
containing
surface
mount
devices
can
cause
damage
to
the
components
and
the
board;
never
bend
or
flex
boards.
Oo
not
heat
or
cool
the
boards
unnecessarily,
as
the
board
materials
Seneen
expand
and
contract
by differing
amounts
which
can
cause
the
components
and
solder
connections
to
be
stressed.
Heating
t
Heaing
Never
rub
or
scrape
chip
components
as
this
can
change
their
value.
ae
|
ca
Do
not
slide
the
board
across
any
surface.
When
using
a
soldering
iron,
take
care
and
apply
suitable
pressure.
For
preference,
use
a
soldering
iron
rated
at
approx.
30 W with
a
thermostatic
control
to
give
soldering
temperatures
of
approx.
225
to
250
°C.
Do
not
re-use
any
chips
removed
from
the
board.
When
attaching
chips,
solder
as
quickly
as
possible
so
as
not
to
damage
the
terminals
and
body
of
the
chip.
Do
not
touch
the
termi-
nals
directly
with
the
soldering
iron.
bide
While
soldering,
keep
the
chip's
body
in
contact
with
the
board.
Soldering
Prasauire
4
Cleaning
Attaching a Chip
Place the chip in the correct position and temporarily solder one
terminal to the copper surface.
Holding
the
chip
body
with
a
pair
of
tweezers
to
position
it
accu-
Tees
rately,
complete
the
soldering
at
each
terminal
in turn.
Solder
Solderg
Removing a Chip
Heat
the
solder
for
2
to
3
seconds
at
each
terminal
of
the
chip.
Remove
the
molten
solder
with
solder
wick.
Holding the chip with a pair of tweezers, remove it gently from the
board while the solder at each terminal is molten.
Wick off all excess solder from the board, so that it is ready for new
components.
Working with Chip Components

Circuit Description
The receiver consists of a single main PCB. Circuit diagrams are in the
pocket on the rear cover. Some receivers may have an extension board
in place of the main microprocessor U700 (see page 20).
The adjacent “main” block diagram shows the main functional blocks.
For copyright reasons, the VideoCrypt functions are given on a sepa-
rate sheet. (See the pocket on the rear cover.) The following descrip-
tion is for receivers with an integral VideoCrypt decoder. Most of this
also applies to non-VideoCrypt receivers; The differences are indicated
‘on page 24.
TUNER AND VIDEO PROCESSING
Tuner
When a programme is selected via the handset, data received by the
sensor IR 700 is fed, as TTL level data, to the microprocessor U700. In
turn U700 supplies tuning data to a frequency synthesiser U100. The
synthesiser forms the reference oscillator for the phase locked loop
which
controls
the
local
oscillator
in
the
tuner.
The
prescaler
output
of
the tuner is obtained by dividing the local oscillator frequency by 128.
The local oscillator is set 479.5 MHz higher in frequency than the
chosen programme and is mixed with the incoming signal. The signal
is then amplified by an IF stage centred at 479.5 MHz with a band-
width of 27 MHz. The 479.5 MHz FM signal is then demodulated in the
tuner to give the required composite video baseband signal (CVBS)
output.
The frequency synthesis is performed by U100 which receives divider
ratio data for the required programme via the 3-wire serial bus from
the microprocessor U700. The data is on pin 5, clock on pin 4 and
select on pin 3 of U100. The synthesiser generates a reference fre-
quency from the 5.625 MHz crystal (X100) input on pins 1 and 2. The
prescaler input on pin 11 of U100 is divided down according to the
divider ratio sent from U700 and compared with the generated
reference (see also the diagram on page 20). The error signal from the
phase locked loop (pulses on pin 14 of U100) is integrated by Q100
and associated components. These determine how much of the 30 V
supply appears as the tuner control voltage on pin 15 of the tuner. The
5V supply to the tuner is on pin 12.
To compensate for the LNB's local oscillator frequency conversion
offsets, information on the position of the signal relative to the
27 MHz bandpass filter within the tuner passes from pin 10 of
TUNER100 to pin 35 of U700. The frequency synthesised within U100 is
then varied under control from U700. This automatic frequency
control (AFC) keeps the signal central in the 27 MHz bandpass filter.
in dual-input models of the receiver, the Tuning Menu can be used to
specify whether a programme is received via LNB 1 or LNB 2. The line
LNB_SELECT controls both the supply and select for the LNBs and
comes from pin 21 of U700. Pin 4 of the tuner is the select line for
LNB1 and it is enabled by Q106; pin 6 is the select line for LNB 2 and it
is enabled by Q107. Power to the LNBs passes through the tuner via
pin 3 for LNB 1 and pin 5 for LNB 2. There are further details about the
LNB supply in the SMPS circuit description on page 19.
The baseband signal from pin 13 of the tuner is low pass filtered by
R110, C112, C113 and L100. It is then buffered by emitter follower
Q101 and AC coupled into the video input pin (pin 20) of the sound
and video processor and switch matrix (U500) by C548. The baseband
signal from U101 emitter is also high pass filtered by C556, C555, C549,
R539, R538 and L503 to filter out the video, and the resulting audio
subcarriers are input to the FM input (pin 23) of the sound and video
processor (U500).
Dual Bandwidth Tuner
The bandwidth of the tuner is controlled by the BANDWIDTH control
line which comes from pin 14 of the modulator chip U200. This pin is
an open collector output and must have the pull up resistor R112
fitted to function properly. U200 is under the control of the
microprocessor U700 via the ?C bus.
MSS 100 Series Satellite Receiver
ENGLISH

For an 18/27 MHz tuner the video gain of the receiver is the same at
both bandwidths. For a 27/36 MHz tuner the video gain must be
reduced when 36 MHz is set at the Set Up Programme Menu. This is
because the video level from the tuner will be larger for the 36 MHz
bandwidth due to the deviation being 22 MHz/volt instead of 16
MHz/volt for the 27 MHz bandwidth. The gain reduction is achieved
by the variable gain amplifier inside U500 and is done automatically
by the software when the appropriate selection is made.
Video processing within U500
The baseband enters U500 at pin 20 where it enters a variable gain
video amplifier whose output can be selected to be normal or in-
verted (for C-Band video). This signal is also further processed in U500
by asecond amplifier and the network connected between pins 15
and 18 to perform the PAL de-emphasis. The output of this amplifier
provides an input to the onboard 6 x 3 video switch which is called
FLAT (since it has no de-emphasis). The output of the second amplifier
also provides an input to the video switch matrix which is called PAL
(since it is PAL de-emphasised). This signal also exits U500 at pin 15
andis filtered by L501, L502 and associated components. This then
passes through a sound trap comprising L500 and associated compo-
nents (if fitted) before undergoing group delay compensation by
Q500, Q501 and associated components. The signal then re-enters
U500 at pin 13 where the energy dispersal is removed by a sync. tip
clamping circuit. Most satellite signals are transmitted with energy
dispersal to distribute the energy more evenly across the transmission
bandwidth. Energy dispersal is a triangular 25 Hz waveform added to
the signal. If it is not removed, flickering can occur on the screen. The
signal on pin 13 provides an input to the switch matrix which is called
CLAMPED. The three other inputs to the switch matrix (U500) are
INTERNAL DECODER RETURN, VCR RETURN and EXTERNAL DECODER
RETURN.
The decoder SCART video options are limited to PAL, FLAT or
CLAMPED in the Set Up Programme Menu.
B-BAND IN
FLAT (Baseband)
Internal Decoder Return
PAL
De-emphasised
$3 VID RTN
FROM VIDEOCRYPTI
$2
VID
RTN
VCR
Return
FROM
VCR
SCART
$1
VID
RTN
External
Decoder
Return
FROM DEC SCART)
BLACK LEVEL|
AD.
VIDEO BLOCK
DIAGRAM
STV0056
$3 VID OUT
Internal Decoder:
-
Circuit Description
L___B&> extern J
$1 VIO OUT Decode

The VCR SCART video will be CLAMPED, INTERNAL DECODER
RETURN or EXTERNAL DECODER RETURN depending upon the
status of VC_ACTIVE and DEC_PIN_8.
The TV SCART will switch between CLAMPED, INTERNAL DE-
CODER RETURN, VCR RETURN and EXTERNAL DECODER RETURN
depending on the status of VC_ACTIVE, VCR_PIN_8 and
DEC_PIN_8.
Colour Graphics Generator
The video signal at pin 9 of U500 is already clamped at the correct
level for the graphics chip and so no buffer is required. R601 and
D600 limit the amplitude of the video to less than 5 V, as with
noisy signals the video amplitude could exceed 5 V and break
through the blue screen menus.
U600 and associated components form the graphics generator
which is used to generate the menu background colour and on-
screen text characters, under control from the microprocessor
U700. The background colour is fixed to blue. There are two
graphics modes: plain background and superimposed on a
programme.
There are two oscillators associated with U600. The first oscillator
is the crystal X600 which generates a frequency of 17.734 MHz.
This is exactly four times the frequency of the colour information
which is used to generate the background colour and is therefore
relevant to plain background mode. If this frequency is not within
a few hundred hertz of 17.734 MHz, there may be no colour to
the on-screen graphics display (it depends on the tolerance of the
TVset). The second oscillator is within U600 and it runs at ap-
proximately 7 MHz, its frequency being set by external compo-
nents L602, C609 and C610. This is used, together with horizontal
and vertical sync. pulses, to generate the characters and their
Positions on the screen. For the superimposed on picture mode
the horizontal and vertical sync. pulses enter U600 at pins 18 and
19 respectively. For plain background mode the horizontal and
vertical sync. pulses are generated within U600. For both these
modes, the white level for the characters is generated by resistors
R603 and R604.
The video signal which enters U600 at pin 10 therefore emerges
atpin 8 with any superimposed graphics such as menus, pro-
gramme status information etc.
The STN_ID line at pin 39 of U700 informs U700 that there is a
valid video signal. U700 then generally commands U600 to
superimpose graphics onto a picture for the Set Up Programme
Menu (and similar menus). However, if you press the TV/SAT key
while the menu is displayed, U700 commands U600 to insert a
plain coloured background instead of the picture (see also page
20).
Note that part of U600 is also used as a port expander for U700.
TV SCART
The video output at pin 8 of U600 is buffered by emitter follower
Q601 and then output via R611 at pin 19 of the TV SCART. The
emitter follower also supplies video to the UHF modulator. Both
the TV SCART and the modulator have on-screen graphics.
VCR SCART
The video signal at pin 9 of U500 is buffered by the emitter
follower Q600 and then output via R623 at pin 19 of the VCR
SCART. There are no on-screeen graphics on the VCR SCART.
Decoder SCART
The video signal at pin 8 of U500 is buffered by the emitter
follower Q605 and then output via R618 at pin 19 of the DE-
CODER SCART. There are no on-screen graphics on the DECODER
SCART,
MSS 100 Series Satellite Receiver
ENGLISH

Output to the Modulator and Optional AV sockets
The video at the emitter of Q601 (labelled GRAPHICS_OUT in the
circuit diagram) also passes via a filter comprising C202, C213, C214
and R216 to the UHF modulator. Resistors R214 and R215 attenuate
the video to 500 mV pk to pk.
Note that because this video to the modulator is fed off from a point
by
the
TV
SCART,
it
contains
on-screen
graphics
which
will
be
recorded
if a VCR is connected to the receiver by a UHF lead. (Video to the VCR
SCART does not contain on-screen graphics.)
RGB Disable Switch
If
an
external
MAC
decoder
is
connected
to
the
decoder
SCART
and
set
to RGB
output,
the
R,
G
and
B
signals
are
simply
looped
from
the
decoder
SCART
to
the
TV
SCART.
Pin
16
of
the
decoder
SCART
is
buffered
to
the
TV
SCART
by
Q603.
When
pin
16
of
the
TV
SCART
is
0 Vthe TV is in PAL mode, when pin 16 of the TV SCART is at 5 V the
TV is in RGB mode. Pin 16 of the decoder SCART is disabled by the
microprocessor U700 switching on Q602. This shorts the base of Q603
to ground which in turn switches pin 16 of the TV SCART to ground
therefore disabling the TV's RGB function. RGB disable is performed
when in menus, because the menus are PAL only.
UHF MODULATOR
The RF output to the TV is generated by a frequency synthesisied UHF
modulator. “his allows the RF output to be precisely tuned to any
channel with: the UHF bands IV and V (channels 21 to 69).
The circuitry :onsists of two main parts, a loop-through amplifier
(U201) betwean the aerial input and the output to the TV/VCR, and
the UHF mos .:lator itself, which comprises U200 and associated
components.
The
heart
ot
xe
modulator
is
the
IC
U200,
a
block
diagram
of
which
is
shown on ps. 18. It comprises the following:
* a pha: locked loop frequency synthesiser that covers the full
UHF Sand;
® anar stitude modulator to modulate the UHF carrier with the
video:
® an au:o oscillator for the sound subcarrier;
¢ avide> clamp to ensure the correct modulation index.
Tuning is er anied by a DC tuning voltage in the range 0 to 24 V being
applied to tne varicap diode D200.
The tuning voltage is derived from pulses on pin 7 of U200. They are
integrated by Q200, R207, R206, C208 and C209 and associated
circuitry and eventually fed to the cathode of D200.
The audio subcarrier oscillator circuit is connected across pins 2 and 3
of U200. This is set at the audio subcarrier frequency (6 MHz for PAL |;
5.5 MHz for PAL G). The audio signals from pins 6 and 10 of the audio
processor U500 are combined by R523 and R524, AC coupled by C200,
pre-emphasised by C201 and R200 and then input at pin 1 of U200.
The audio level at this point should be approximately 500 mV pk to pk
at
full
volume.
Note
that
the
outputs
at
pins
6
and
10
of
U500
are
also
fed to the TV SCART, so that the modulator always has the same audio
source as the TV SCART.
The video signal (labelled GRAPHICS_OUT in the circuit diagram)
passes via L202, which, together with C213 and C214, forms a low pass
filter. Resistor R214 and R215 attenuate the video to 500 mV pk to pk.
The video signal is fed into pin 19 of U200. This is used to amplitude
modulate the VCO output. The modulation index is set to be 80% by
resistor R213 on pin 17 of U200.
The RF output from pin 15 of U200 is fed via C217 and R217 into U201
an RF loopthrough amplifier chip which mixes the signal with the
terrestrial RF channels. When the satellite receiver is in standby the
UHF oscillator is switched off by U200 under control of the microproc-
essor
U700
via
the
I?C
bus.
~
Circuit Description

VIDEO ADJUST RF OUTPUT
MIXER
PRESCALER
(8)
RF OSC. ON/OFF
CHARGE PUMP
(BANDWIDTH)
31,25 kHz
The
port
output
bit
on
pin
14
of
U200
is
used
to
control
the
bandwidth
of
the
tuner.
Since
this
pin
is
an
open
collector
output
it
must
have
a
pull-up
resistor
(R112)
to
function
properly.
MSS 100 Series Satelli Receiver
ENGUSH

SWITCH MODE POWER SUPPLY
Mains Input and Rectification
Diodes D1, D2, D3 and D4 rectify the AC mains voltage and, together
with smoothing capacitor C3, provide the DC input HT for the SMPS.
R1 provides inrush current limiting to protect the diode bridge. C1 and
T1 form a mains filter to minimise the feedback of RFI into the mains
supply. Asymmetrical mains pollution is reduced by the insertion of C6
between the primary ground and the secondary chassis ground. This
component is required to satisfy the mains isolation requirements and
is a safety-critical component (as are SK1, FS1, and T2). These compo-
nents must only be replaced by components of the correct type (see
parts lists).
SMPS Controller U1
U1 is a single chip T0220 switch mode power supply IC. It runs at
approx 100 kHz. R2 and C4 determine the loop response and the
power-up delay. Feedback from the sense winding (pin 7 and pin 9) is
rectified by R3, D8 and C5 to provide a DC voltage which is coupled to
DC outputs. When this voltage is greater than approximately 21 V
current flows through D7 into the control pin of U1 reducing the
switch-on time of the device hence the power supply is kept in regula-
tion.
D5 and D6 provide the snubbing of the leakage voltages preventing
them rising above the 700 V breakdown voltage of U1.
Secondary ‘Nindings of T2
The secondary windings of the transformer T2 provide the following
voltages after rectification and smoothing: +5 V (pin 12), +17 V (pin 8),
+22 V (pin 2). and +29 V (pin 4). The 17 V provides the supply for the
LNB when se: “o vertical and is also sub-regulated by U3 to 12 V to
provide power for U500 and U302 as well as some of the video
circuitry.
The 22 V is used for the horizontal LNB supply; the 30 V is used to
provide tunir2 volts for the modulator U200 and for the tuner.
LNB Suppiy Switching
U2A and Q2 act as a programmable linear regulator to provide
accurate higr.y regulated LNB outputs. A reference voltage is applied
to pin 3 of U24 via Q7, Q8, D17 and associated components. The
output of the operational amplifier U2A will switch on Q2 until the
voltage on pin 2 of U2A is the same as the voltage on pin 3. R18 and
R19 are in the ratio of 5:1 hence 3V on pin 3 will provide approxi-
mately 15 V on the LNB supply. Q3, R16 and R17 provide current limit
at 450 mA to protect Q2 and the power supply. D15, Q4 and
associated components provide LNB short circuit protection. If the LNB
supply drops below 10 V the transistor Q4 is turned off and the
LNB_MON signal is detected by the micro controller U700. The LNB
supply can be turned off by turning on Q7 which holds pin 3 of U2A at
0 Vand hence the output at 0 V.
To reduce dissipation, the input to Q2 is switched by Q5, Q6 and Q1
and associated components depending if horizontal or vertical volts is
selected. :
By adding a 22 kHz tone via R24, R25 and C23 to pin 3 of the U2Aa
22 kHz tone can be superimposed on the LNB supply.
Power Supplies during Standby
The receiver has a low power mode. if this is set at the Power-on
Options then the LNB supply is turned off and both U200 and U500
are placed in low power mode thus reducing the power taken by the
receiver when in standby to approximately 10 W. If this option is not
set then in standby the LNB is still powered, which is necessary in very
cold climates. However U200 and U500 are still placed in low power
mode.
Circuit Description