AOR SDU5500 User manual

1
Section1,1-1
(1) SDU5500 Index
1 Index ............................................................................................ 1
1-1 Introduction .................................................................................. 1
1-2 Taking care of the unit .................................................................. 2
1-3 Power requirements ..................................................................... 2
1-4 Operating anomalies .................................................................... 2
1-5 Accessories supplied .................................................................... 2
1-6 Technical high-lights ..................................................................... 3
2 Controls and connections .......................................................... 4
2-1 Front panel controls ...................................................................... 4
2-2 Rear Panel ................................................................................... 5
3 LCD, keys, legends & menus ..................................................... 6
3-1 Description of LCD legends .......................................................... 6
3-2 SDU5500 menu overview ............................................................. 10
3-3 Important considerations .............................................................. 14
3-3-1 LCD resolution ............................................................................. 14
3-3-2 Significance of receive STEP size ................................................ 14
3-3-3 Significance of RBW (Resolution Band Width) ............................. 15
4 Making the SDU5500 ready for operation ................................. 15
4-1 Configuration of the AR5000 companion radio ............................. 15
4-2 Configuration of the AR3000A companion radio ........................... 17
4-3 Configuration of an ICOM companion radio .................................. 19
4-3-1 Example set-up for the ICOM IC-R7100 receiver ......................... 20
4-3-2 Example set-up for the ICOM IC-R8500 receiver .......................... 20
4-4 Operation with an “Other” companion receiver ............................. 21
5 General operation of the SDU5500 ............................................ 23
5-1 Using the SDU5500... sequence to use ........................................ 23
5-2 Spectrum analyser mode .............................................................. 28
5-3 Step resolution mode ................................................................... 30
5-4 Channel scope mode ................................................................... 33
5-5 Passive bandscope operation ...................................................... 36
6 Special considerations .............................................................. 37
7 Computer control information ................................................... 38
8 Specification ............................................................................... 42
1-1 Introduction
Thank you for purchasing the SDU5500 Spectrum Display Unit. For years AOR has been marketing the
worlds’ first colour spectrum display unit SDU5000 for professionals and the top-end of hobbyist
listeners. The SDU5500 is a worthy successor to the SDU5000, using a large high resolution LCD
display (similar to high priced dedicated spectrum analysers) backed by the latest microprocessor
technology to ensure high versatility and reliability. To get the best possible results, we recommended
that you read this manual to fully familiarise yourself with the SDU5500.
Every effort has been made to make this manual correct and up to date. Due to continuous
development of the product and by error or omission, anomalies may be found and this is
acknowledged.
© This manual is protected by copyright AOR Ltd 1999. No information contained in this manual may be
copied or transferred by any means without the prior written consent of AOR Ltd. AOR and the
AOR logo are trade marks of AOR Ltd. All other trade marks and names are acknowledged. E&OE

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Section 1-2, 1-3, 1-4, 1-5
1-2 Taking care of the unit
There are no internal operator adjustments. In the unlikely event of servicing being required, please
contact your dealer for technical assistance.
Do not use or leave the SDU5500 in direct sunlight (especially the LCD). It is best to avoid locations
where excessive heat, humidity, dust and vibration are expected. Always keep the SDU5500 free from
dust and moisture. LCD contrast & selection of negative / positive display may be adjusted via menus,
adjust appropriately to your operating environment.
&Note: Never push or knock the LCD screen - which is very fragile and shock sensitive.
Daily care
Use a soft, dry cloth to gently wipe the SDU5500 clean, never use abrasive cleaners or organic solvents
which may damage certain parts. Treat the unit with care, avoid spillage or leakage of liquids into the
cabinet and power supply. Special care should be taken to avoid liquid entering around the keys, spin
wheel dial or via the connection sockets.
1-3 Power requirements
Depending upon the world market area, the SDU5500 may be provided with either a suitable a.c./d.c.
power unit or just the d.c. lead with correct d.c. plug type fitted. The SDU5500 is designed for operation
from a nominal 12V d.c. regulated power supply (12 to 14V is acceptable), which should be capable of
supplying a minimum of 1A continuous, ideally a 2A unit should be employed.
&Note: Never connect the SDU5500 directly to an a.c. supply.
The d.c. input socket uses a mini power connector subject to EIAJ RC-5320A
and is wired centre positive (+), the cable is marked with a stripe identifying the
positive connection, the chassis of the unit is at negative ground. To minimise
the potential for power cable interference, it is suggested that a ferrite clamp be
fitted to the connecting cable.
&SAFETY NOTICE - Always disconnect the power supply from the a.c. socket when not in use.
1-4 Operating anomalies
Should the SDU5500 appear to behave strangely, normal operation may easily be regained by resetting
the microprocessor. Simply power down the SDU5500 and disconnect the power supply... leave for 30
seconds then re-connect and power-up again.
1-5 Accessories supplied
The following items are provided in the carton box:
1 x Control lead for the AR5000 (9-pin to 9-pin D-type male)
1 x BNC patch lead for IF connection
1 x Operating manual
1 x a.c. power supply or d.c. cable
(in this case the white stripe is positive) - depending upon world market area.
&Note: If used with the AR3000A, a small modification is required to the receiver in order to provide
the required 10.7 MHz IF output. If using the ICOM IC-R7100 or IC-R9000, the optional ICOM CT17
(RS232/CIV) interface is required.

3
1-6 Technical high-lights
•Menu driven operation
All facilities are accessible via dedicated keys and on-screen menus.
•Full inter-connection with the AR5000
The AR5000 can be operated from the SDU5500 providing selection of centre frequency, receive
mode, etc. Any frequency spotted and monitored by the SDU5500 may be received by the AR5000
straight away.
•Direct reading of receive frequency and input level
By placing the cursor on any spot frequency, you can read its frequency and input dBm level
on-screen. When connected with the AR5000, the SDU5500 virtually works as a spectrum analyser
over the frequency range of 10kHz to 2600MHz as the centre frequency is always the receive
frequency in spectrum analyser mode.
•Wide spectrum coverage
The SDU5500 covers a maximum of 10 MHz (± 5MHz) spread against the input frequency.
•Dual frequency resolution
SDU input filters may be toggled between 5kHz or 30kHz resolution.
•Wide input range Input range
Of -10dBm to -90dBm by using 2 selectable gain settings.
•Highly accurate frequency management
Through the DDS controlled Local Oscillator circuit.
•Graphical display
Wide variety of graphical display and statistical analysis.
•Remote control via PC
All keyboard operations of the SDU5500 can be mimicked by PC via RS232. Also acquired data
can be downloaded to PC.
•Compatibility with non-AOR receivers
Any companion radio receiver which is equipped with a 10.7MHz IF output may be used with the
SDU5500. It is possible to use a companion receiver with an IF not of 10.7 MHz but within the
range of 5.7 to 15.7 MHz by reprogramming the IF frequency employed by the SDU5500, however
In order to provide a useful bandwidth of at least 1 MHz (+/- 500kHz), as a rule of thumb, the limits
of IF should be considered as 6.7 to 14.7 MHz. Sweep direction is selectable depending on the
heterodyne configuration of the radio, however the maximum sweep span may be narrower than
10 MHz due to the IF characteristics and IF frequency of the companion radio. If being used with
and ICOM IC-R7100 or IC-R9000, the optional ICOM CT-17 (RS232/CIV) interface will be required.
Section1-6

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(2) Controls and connections
2-1 Front panel controls
The front panel of the SDU5500 is dominated by the large LCD. Controls are ‘grouped’ to assist efficient
operation, there are a total of 18 keys in addition to the on/off switch and spin wheel dial.
1 Power switch
Press once to latch the switch in, switching on the SDU5500. To switch off the SDU5500, press the
switch a second time, the switch latches outward.
2 Liquid Crystal Display
The large high resolution back-lit LCD defaults to white graphics & text on a blue background with the
bottom-row functions in reverse contrast. The colours may be reversed (blue graphics & text on a white
background) and the contrast may be adjusted.
3 Function keys
Six function keys are located under the LCD. There is no ‘printed legend’ accompanying the keys as
their operations are defined by which menu is active on the LCD... there are a total of seven menus
numbered from 1 to 7 inclusive (the menu number is ALWAYS displayed in the extreme lower-left corner
of the LCD). This implementation is often referred to as “soft keys”.
4 Spin wheel dial
A rotary encoder is provided to simplify movement of the marker position on the LCD. This is very
convenient and is the most natural method of marker frequency change. The marker is displayed as a
thin vertical line with downward / upward triangles further easing visibility. The current marker numeric
frequency reading is displayed directly above the graticule, along with signal level in dBm.
5 Numeric ‘ten keys’
The entry of centre-frequency (receive frequency) is via the ten keys which are labelled to
plus decimal and enter .
6 Bail bar
A tilt bail bar is provided under the front panel (on the bottom case half) so that the SDU5500 may be
tilted upward at the front to improve visibility in certain installations.
Section2,2-1

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2-2 Rear Panel
The rear of the SDU5500 features two 9-pin D-type sockets for connection to the companion radio and
PC, a BNC socket is provided for IF input and a d.c. input socket for power. Blanking plates cover the
unused sections of the rear panel, these are for possible future expansion / options.
1 DC 12V (d.c. input power
socket)
Connect a suitable regulated 12V
d.c. power supply to this socket
using the supplied connection lead,
the power supply should have a
minimum continuous capacity of 1A
or greater, ideally a 2A supply
should be employed.
The connector is subject to EIAJ
RC-5320A and is wired centre
positive (+), the cable is marked
with a stripe identifying the positive
connection.
To minimise the potential for power cable interference, it is suggested that a ferrite clamp be fitted to the
connecting cable. (In some market areas a suitable power supply may be provided).
&Note: Never connect the SDU5500 directly to an a.c. supply.
2 RX CTR (receiver connection socket)
The supplied 9-way to 9-way ‘D-type’ male to male lead is used to connect the SDU5500 to the AR5000
receiver. If used with another receiver, a suitable serial-adapter or connecting cable will be required.
Wiring should be as follows:
SDU5500 9-pin male 9-pin male (AR5000) 25-pin male (AR3000A)
223
332
5 5 7 GND
774
885
3 PC I/F PC (PC control socket)
A controlling computer may be connected to this 9-pin D-type female socket. As the socket is identical
to that used for the companion radio connection, great care should be taken to avoid connection to the
incorrect socket. Although it is very unlikely that incorrect connection may cause damage, it will cause
unnecessary delay in placing the SDU5500 into useful operation.
Section2-2

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If connecting to a PC, observe the following connection requirements, use a straight RS232 lead
(avoid null modem leads, these will not operate):
SDU5500 9-pin PC 9-pin PC 25-pin
2 2 3
3 3 2
5 5 7 GND
7 7 4
8 8 5
The SDU5500 is fully controllable by PC via the built-in RS232 interface, this includes all keyboard
operations and down loading of the displayed data.
Communication parameter
Data length 8 bit
Parity bit None
Stop bit 2 bit
Baud rate 9600
Flow control X flow
4 RF IN (Intermediate Frequency input socket)
The IF output (10.7 MHz) from a suitable receiver such as the AR5000 should be connected to this BNC
input socket using a 50 OHM patch lead constructed of quality coaxial cable such as RG58/U, UR43,
UR76 etc.
(3) LCD, keys, legends & menus
3-1 Description of LCD legends
The LCD is effectively split into three main sections, the top operating environment, the middle spectrum
trace and the bottom menu selection. A total of 17 specific LCD areas are employed:
Top legends
The top of the LCD provides operational information, a summary is as follows:
CF Centre Frequency (frequency at the middle of the graticule) in MHz.
RBW Resolution Band Width, sampling resolution 5kHz / 30kHz.
RX Type of companion radio configured.
FDIR Frequency sweep direction (ignore unless set to ‘Other’ companion radio type).
STEP Receive tuning step in kHz.
ATT Companion radio attenuator status On/Off (cannot accommodate 0/10/20dB selection).
SPAN Total bandwidth of spectrum display in kHz.
GAIN Toggles the SDU5500 internal amplifier between high and low gain.
PLOT Type of trace, Outline or Paint.
MODE Receive mode (NFM, AM, AUTO etc)
OP.MODE Type of operation employed, SPECT (spectrum), STRES (step resolution),
CHANL (channel scope).
Section 2-2, 3, 3-1

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Middle, graphical display
The middle section of the LCD is mapped into a graticule of ten boxes horizontally and five boxes high.
The horizontal scale is determined by the SPAN (see later under LCD resolution). The vertical scale is
calibrated in 10dBm increments ranging from:
•Hi gain: Baseline is -90dBm with the top line representing -40dBm.
•Low gain: Baseline is -60dBm with the top line representing -10dBm.
Directly above the graticule, the current “Marker” frequency is displayed in MHz with the signal level
displayed in dBm to the right of the frequency. The marker position is controlled using the spin wheel
dial.
Bottom menu soft keys
The bottom of the LCD is occupied by a number of soft keys arranged in seven menus. The mix of keys
varies depending upon operational mode selected. Please refer to section 3-2 of this manual for a menu
overview.
A summary of the 17 LCD areas is presented here:
(1) CF/RF Centre Frequency / Receive Frequency
A frequency at the centre of the screen is always indicated in MHz, the finest resolution is 10 Hz. In
spectrum display and step resolution modes, the legend “CF” (Centre Frequency) is displayed to the left
of the frequency. In channel scope mode the legend “RF” (Receive Frequency) is displayed to the left of
the frequency.
Section3-1

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(2) SPAN Total displayed bandwidth
The centre frequency appears in the middle of the display with frequency extending to the left and right.
The total frequency spread from the left through centre to the right is referred to as the total SPAN and is
indicated in kHz. The maximum span is 10000 kHz (10 MHz) and minimum is 1 kHz.
(3) RBW Resolution Band Width
Two input filters may be toggled for sampling, 5 kHz and 30 kHz. Greater detail is obtained by 5 kHz,
often with a lower baseline while 30 kHz provides faster refresh rates.
(4) GAIN SDU5500 input gain
The input stage of the SDU5500 has two gain settings Hi / Low, this is selectable from menu 2. Input
gain is measured at the input of the SDU5500, not at the companion radio aerial socket. The difference
between high and low gain setting is about 30dB.
(5) RX Companion radio type
The type of companion radio is displayed (selected from those available in RX configuration menu).
When no specific companion radio is connected “Other” is automatically indicated.
(6) FDIR Frequency Direction
This function enables the SDU5500 to display the frequency in normal (left is lower frequency from the
centre cursor) or reverse (left is higher frequency from the centre cursor). This is useful depending the
type of superheterodyne receiver configured while in “Other” operation. The direction is automatically
determined when using one of the supported radio receivers (so the menu item is not available, but
selection is automatically displayed).
(7) PLOT Plot mode
Plot type can be PAINT or OUTLINE. Outline appears closer to the representation of a high priced
dedicated spectrum analyser while paint is often easier to view.
(8) STEP Step frequency
Tuning step size of the companion radio is displayed in kHz format with a resolution of tens of Hz.
(This is not the same as the LCD-step which is based upon the LCD resolution of 304 dots).
(9) MODE Receive mode
The companion radio receive mode is displayed. Not applicable when the radio type is set to “Other”.
(10) ATT Attenuator
Indicates whether the attenuator of the companion radio is ON or OFF. Not applicable when the radio
type is set to “Other” nor with certain radio models.
(11) OP.MODE SDU5500 Operating mode
Three operating modes are provided and may be selected from menu 3:
• SPECT: Spectrum analyser mode
• STRES: Step resolution mode
• CHANL: Channel scope mode
(12) AVR / MAX Averaging and maximum level
Averaging and Maximum level may be selected from menu 6. When “MAX” is selected, the traces on
the LCD are frozen to indicate the strongest signals encountered (if you look very carefully, you will see
that the trace is still updating). To cancel MAX press the [MAX] key a second time. When “AVR” is
selected, the sampling rate is indicated and signals will be averaged over a number of sweeps.
Section3-1

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To cancel AVR, press [AVR] a second time.
(13) Marker Marker / Peak / CPeak
Selection of Marker / Peak / Continuous Peak is made via menu 5 and indicated on the LCD.
In normal spectrum mode, “Marker” is displayed and the spin wheel dial may be used to move the
marker position indicated by a vertical bar with triangular symbols. The frequency and strength of traces
may be read in this manner. The frequency and level can only be read within the confines of the
graticule (out of range reading cannot be made).
“Peak” is displayed when peak hold is activated, the maximum strength of incoming signals will be
frozen on the LCD until the peak facility is disengaged (finishing the current session) or SDU5500
switched off. The spin wheel dial may be used to hop between peaks in order of amplitude.
When “CPeak” is selected, the marker automatically hops to the largest new signal once a sweep has
completed, the frequency of the transmission is displayed to the right of the “CPeak” legend. If you wish
to monitor the automatically identified transmission, press [MK-CF] before a new sweep completes, this
MOVES THE MARKER TO CENTRE FREQUENCY where it may be monitored through the companion
radio.
(14) Signal display graticule
Received frequencies are plotted on the horizontal scale and signal strength on the vertical scale,
showing the over-all effect of signal activity over the given frequency bandwidth (span).
The bottom horizontal line is the ‘baseline’. When signals are encountered, they produce vertical lines,
the higher the line, the stronger the signal. A 50dB range is provided by the graticule which is divided
into 10dB increments.
• Hi gain: Baseline is -90dBm with the top line representing -40dBm.
• Low gain: Baseline is -60dBm with the top line representing -10dBm.
By carefully selecting the gain, it is possible to obtain a total of 80dB between the two settings
(from -90dBm to -10dBm).
(15) Receive Marker
A vertical dotted line with ‘outline triangle markers’ indicates the receive frequency when using channel
scope mode. This is the frequency to which the companion radio is tuned and monitoring.
(16) Menu number
The current menu number (for each of the seven menus) is indicated in the lower left corner of the LCD.
Use the PREV NEXT keys to move between menus or as a short cut, press the wanted menu
number using the ten-key pad.
(17) Function keys
Six function keys are presented horizontally underneath the graticule, each being assigned with a
specific task. The ‘soft key labels’ will be displayed above the function keys on the LCD page-by-page
when the menu is scrolled.
Section3-1

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3-2 SDU5500 menu overview
Operation of the SDU5500 is controlled by seven menus numbered 1 to 7. The menu number is always
displayed in the bottom left of the LCD, even when information is being keyed. The radio type is defined
in menu 1. Use the PREVIOUS MENU PREV and NEXT MENU NEXT keys to move between
menus.
&Note: As a short-cut to menus, it is also possible to use the numeric ten-key pad... so that
immediately accesses menu 1, accesses menu 5 etc.
Some omission and duplication appears in menus (such as STEP in some operating modes) as facilities
change with operating condition.
While inputting numeric data or defining companion radio type, addition sub-menus are often displayed.
The soft keys offer the following facilities:
ESC ENT
ESC: Exit / abort / terminate
ENT: Enter / accept data
ESC BS ENT
ESC: Exit / abort / terminate
BS: Back space
ENT: Enter / accept data
&Note: Either key may be used to complete data entry, on the ten-keypad or soft menus
when offered.
A quick menu guide is presented here:
Spectrum analyser mode (SPECT)
1 PREV RX PLOT CONT B/W NEXT
2 PREV MODE STEP ATT GAIN NEXT
3 PREV SPECT STRES CHANL - NEXT
4 PREV CF SPAN RBW - NEXT
5 PREV MKR PEAK CPEAK MK-CF NEXT
6 PREV MAX AVR - - NEXT
7 PREV <<- <- -> ->> NEXT
Step resolution mode (STRES)
1 PREV RX PLOT CONT B/W NEXT
2 PREV MODE STEP ATT GAIN NEXT
3 PREV SPECT STRES CHANL - NEXT
4 PREV CF STEP RBW - NEXT
5 PREV MKR PEAK CPEAK MK-CF NEXT
6 PREV MAX AVR - - NEXT
7 PREV <<- <- -> ->> NEXT
Section3-2

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Channel scope mode (CHANL)
1 PREV RX PLOT CONT B/W NEXT
2 PREV MODE - ATT GAIN NEXT
3 PREV SPECT STRES CHANL - NEXT
4 PREV FREQ - RBW - NEXT
5 PREV MKR PEAK CPEAK MK-CF NEXT
6 PREV MAX AVR - - NEXT
7 PREV - <- -> - NEXT
‘Other’ companion radio
1 PREV RX PLOT CONT B/W NEXT
2 PREV - STEP - GAIN NEXT
3 PREV SPECT STRES - - NEXT
4 PREV CF SPAN RBW FDIR NEXT
5 PRE MKR PEAK CPEAK MK-CF NEXT
6 PREV MAX AVR - - NEXT
7 PREV <<- <- -> ->> NEXT
11
11
1Menu 1
PREV Move to previous menu
RX Companion radio type
PLOT Toggles between outline and paint
CONT LCD contrast (0 to 160) around 50
is usually best
B/W Toggles between an Blue and White
background
NEXT Move to next menu
22
22
2Menu 2
PREV Move to previous menu
MODE Companion radio receive mode
(not available in ‘Other’ radio operation)
STEP Companion radio tuning step size in kHz.
(not available in channel scope mode)
ATT Toggles the companion radio attenuator
on/off (not available in ‘Other’ radio
operation)
GAIN Toggles the SDU5500 gain between
Hi and Low
NEXT Move to next menu
Section3-2

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33
33
3Menu 3
PREV Move to previous menu
SPECT Places the SDU5500 into spectrum
analyser mode (default)
STRES Step resolution mode
CHANL Channel scope mode (not available
in ‘Other’ radio operation)
NEXT Move to next menu
44
44
4Menu 4
PREV Move to previous menu
CF Receive frequency, enter via the
ten keys in MHz.
FREQ In channel scope mode the legend
“FREQ” is displayed. This is used to
access the sub menu to define
start / end / step setting.
SPAN When using SPECTRUM DISPLAY
MODE “SPECT”, the viewable
bandwidth may be set. Input is via
the ten keys using kHz format.
i.e. for 10 MHz bandwidth (+/- 5MHz)
enter
SPAN is not available in channel scope
mode.
STEP When using step resolution mode, the
legend “STEP” will be displayed, see
the definition in menu 2.
RBW Toggles the input filter Resolution
Band Width between 30 kHz and 5 kHz.
FDIR When using ‘Other’ companion radio,
the sweep direction may be reversed,
at other times the key legend will
be BLANK.
NEXT Move to next menu
55
55
5Menu 5
PREV Move to previous menu
MKR Selected by default. Returns the
SDU5500 to ‘marker’ mode.
PEAK Freezes the current spectrum trace to
show signal peaks.
CPEAK Automatically forces the marker to
move to the highest peak immediately
following a completed spectrum trace,
continuous peak.
MK-CF Force ‘marker frequency’ to equal the
‘centre frequency’ where the trace
may be monitored on the companion
radio. If step size has been selected
appropriately, the exact frequency will
be corrected to the nearest increment
(most appropriate receive frequency)
NEXT Move to next menu
Section3-2

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66
66
6Menu 6
PREV Move to previous menu
MAX When “MAX” is selected, the maximum
height of traces are frozen on the
display. This will result in ‘peaks’
where transmissions have taken place,
one side effect is that the baseline will
tend to build-up a 5 to 10dB solid bar
due to random background noise.
This is a useful facility to ‘trap’
occasional transmissions over a long
time-scale and to check on band
allocation for transmission licence
issuers. Press MAX a second time to
restore a normal trace. A reverse
contrast “MAX” legend confirms selection.
AVR When “AVR” is selected, the average height of traces are calculated and displayed on the
LCD. This causes the display to be a little sluggish at detecting transmissions when they
first appear but permits them to remain visible for longer when the transmission stops. The
effect is a ‘wave’ of activity, useful for assessing band activity in a relatively short period of
time. Once activated, the buffer size must be allocated between 2 and 32 frames inclusive.
A reverse legend “AVR” is displayed on the LCD to confirm operation. While the buffer is
loading, the number of frames is indicated until the programmed number has been sampled,
after this point the specified number of frames will be averaged on an on-going basis. Press
AVR a second time to restore a normal trace. A reverse contrast “AVR” legend confirms
selection.
NEXT Move to next menu
77
77
7Menu 7
PREV Move to previous menu
<<- Moves the centre frequency down by
half the span. For example, if the span
is set to 10000 kHz (10 MHz), the centre
frequency will be lowered by 5000 kHz
(5 MHz)... so that a centre frequency of
123 MHz would become 118 MHz.
Not available in channel scope mode.
<- Moves the centre frequency down one
channel step. i.e. if the receive
frequency is 125 MHz and step is
25 kHz, the centre frequency will move
down by 25 kHz to 124.975 MHz.
-> Moves the centre frequency up one
channel step. i.e. if the receive
frequency is 125.000 MHz and step is 25 kHz, the centre frequency will move up 25 kHz to
125.025 MHz.
->> Moves the centre frequency upward by half the span. For example, if the span is set to
10000 kHz (10 MHz), the centre frequency will be increased by 5000 kHz (5 MHz)...
so that a centre frequency of 123 MHz would become 128 MHz. Not available in channel
scope mode.
NEXT Move to next menu
Section3-2

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3-3 Important considerations
3-3-1 LCD resolution
The LCD provides high resolution of 304 horizontal dots from the left to right edges of screen.
As a result, there are about 30 steps per graticule division with ten divisions making up the total width.
The relationship between frequency and LCD-step is determined by the programmed SPAN width.
Span is set up in menu 4 while in SPECTRUM DISPLAY mode “OP.MODE : SPECT”. The minimum
displayed bandwidth is 1 kHz (+/- 500Hz) and the maximum displayed width is 10000 kHz (10 MHz)
representing ± 5 MHz. Numeric entry is in kHz format from 1 to 10000 inclusive.
To calculate the LCD-step, divide the SPAN bandwidth in kHz by 304. Examples are as follows:
10000 kHz (10 MHz) = 32.894736 which is truncated to 32.89 kHz
5000 kHz (5 MHz) = 16.44 kHz
2000 kHz (2 MHz) = 6.57 kHz
1000 kHz (1 MHz) = 3.28 kHz
500 kHz = 1.64 kHz
100 kHz = 0.32 kHz (320 Hz)
It is possible to force the LCD-step to equal the receive tuning step using a similar process. Multiply
the receive tuning step size in kHz by 304 (dots) to obtain the required total span width in kHz.
For example, for a 5 kHz tuning and LCD step, 5 x 304 = 1520 kHz span
The following table presents commonly used step sizes:
1 kHz 304 kHz (0.340 MHz)
5 kHz 1520 kHz (1.520 MHz)
6.25 kHz 1900 kHz (1.900 MHz)
9 kHz 2736 kHz (2.736 MHz)
10 kHz 3040 kHz (3.040 MHz)
12.5 kHz 3800 kHz (3.800 MHz)
20 kHz 6080 kHz (6.080 MHz)
25 kHz 7600 kHz (7.600 MHz)
32.89 kHz represents maximum span of 10000 kHz (10 MHz)
3-3-2 Significance of receive STEP size
Due to the necessary calculation of total span width divided by LCD-step resolution of 304 dots, the
marker frequency will usually display an ‘approximate’ frequency only... especially as the total span
width is increased above 1 MHz or so.
However, if an appropriate step size has been set, the SDU5500 / companion radio will automatically
calculate the ‘likely’ exact frequency when the MK-CF (marker to centre frequency) key is pressed.
For example: If the centre frequency is set to 125 MHz, the span set to 10000 kHz and step size to 25
kHz, the marker position of a strong airband transmission may appear at 126.15131 MHz, clearly not the
‘exact’ wanted frequency. However by pressing the MK-CF key of menu 5 will change the centre &
marker frequency to exactly 126.15000 MHz, this is clearly the correct frequency being the closest 25
kHz multiple to 126.15131 MHz.
Section3-3, 3-3-1, 3-3-2

15
It is most important to set up the step size appropriately. If you are using the AR5000 companion radio
with receive mode set to AUTO, the step size will be taken care of automatically by the receiver’s built in
factory programmed bandplan (specific to each market area)... this is the ideal companion to the
SDU5500.
3-3-3 Significance of RBW (Resolution Band Width)
RBW sets the SDU5500 input filter and ‘sampling’ rate, either 5 kHz or 30 kHz. Selection of 30 kHz will
provide a faster trace update, 10 MHz being swept in about two seconds... sampling every 30 kHz.
Selection of 5 kHz will provide a slower trace update, 10 MHz being swept in about six seconds...
sampling every 5 kHz. This provides greater accuracy and lower baseline, making signals easier to see.
The balance between speed / resolution will depend upon the type of operation employed. Also, with a
wide span of around 10 MHz, each LCD-step is about 32 kHz (refer to the LCD resolution table) which
makes use of the 5 kHz RBW setting of little advantage in real terms.
(4) Making the SDU5500 ready for operation
It is possible to configure the SDU5500 for operation with a number of companion radios, the following
provides common set-ups.
4-1 Configuration of the AR5000 companion radio
•Connect a suitable power supply
using the d.c. lead provided.
Ensure the correct polarity is
observed, the stripe signifies
positive. (In certain market areas,
a suitable power supply may be
provided).
• Connect the 9-pin to 9-pin
connection lead between the RX
CTR socket of the SDU5500 and
REMOTE socket of the AR5000.
• Connect the 50 OHM BNC patch lead between
the RF IN socket of the SDU5500 and the IF OUT socket of the AR5000.
Cold start
It is important that the AR5000 (or AR5000+3) is switched on FIRST, press the POWER switch of the
AR5000 so that the display appears on the radio. The AR5000 must be set to 9600bps baud rate
(FUNC CONFIG UP UP UP SUB DIAL 9600bps ENTER), on earlier production units, check that the
delimiter is set to CR+LF. Ensure that the AR5000 is in VFO mode (VA, VB, VC, VD, VE).
Now switch on the SDU5500. The first time the SDU5500 is switched on, or whenever power is
removed from the SDU5500, a COLD START sequence needs to be followed. This involves selecting
the required receiver via the SDU5500 companion radio configuration menu. As long as power is not
removed from the SDU5500 (even though it may be switched off with the power feed still connected),
the SDU5500 will remember which companion radio is in use.
&Note: The SDU5500 CPU draws a very small current for backup purposes even though the
SDU5500 power switch is off.
Section 3-3-3, 4, 4-1

16
The SDU5500 LCD will display various details. Under the item “RX” (third line down from the top left of
the LCD), “Other” radio will be displayed with the CF (centre frequency) of 10.7 MHz.
Ensure that menu item “1” is displayed in the lower left corner of the LCD, if not use the PREV
(previous) and NEXT keys. Press RX to display the COMPANION RADIO configuration menu.
Use the spin wheel dial to highlight “AR5000” then press . The legend “AR5000 Connected” will
briefly be displayed then the CF readout will display the current receive frequency of the AR5000 and
the RX readout will confirm AR5000.
Should any fault occur in connection with the AR5000 at this stage, the SDU5500 CPU will identify the
companion radio as “Other”. In this case check the AR5000 baud rate setting (which should be
9600bps) and connection lead.
Warm Start
Once the SDU5500 has been configured for the AR5000 companion radio following a cold start (or any
other receiver in use), it will not be necessary to enter the receiver details again as long as the SDU5500
remains connected to power (presuming that you wish to continue using the same receiver type)... even
after the SDU5500 has been switched off and back on again.
AR5000 auto switch on
Once the SDU5500 is capable of operating from a warm start, the AR5000 will be switched on
automatically when the SDU5500 is powered up. The SDU5500 will attempt communication twice, the
first time the AR5000 will be switched on, the second will establish communication.
Cold start / Hot start
The initial display which appears on the LCD after switching on depends on whether the SDU5500 has
remained connected to a power supply since last use. When the cold start is performed (if power has
been removed), the SDU5500 will start with menu page 1 while menu page 4 will appear when the
SDU5500 is hot-started. Either way, shuttling from page-to-page is possible.
General operational notes
The AR5000 will now be operated from the front panel of the SDU5500, receive frequency, mode,
attenuator & tuning step size may be controlled. Only the MAIN DIAL, SUB DIAL, VOLUME, SQUELCH
and POWER controls of the AR5000 will be available during inter-connect with the SDU5500.
In order to keep the SDU5500 and AR5000 frequency readout in unison, the AR5000 is ‘polled’ once per
second, this is called “automatic renewal of centre frequency” (the poll may be paused during certain
menu conditions). In early AR5000 production, a small flick in s-meter may be noted during the ‘poll’,
should this present an annoyance on a particular transmission, consider temporarily selecting “Other”
receiver and using the SDU5500 as a passive bandscope with the AR5000.
The minimum specified tuning step size when used with the SDU5500 is 10 Hz (even though the
AR5000 can independently tune in 1 Hz steps). Any digits below 10 Hz will be ignored, the acceptable
step sizes being in the range 10 Hz to 999.95 kHz inclusive.
Section4-1

17
Receive mode
When the AR5000 receive mode is set from the SDU5500, the following results:
SDU5500 setting AR5000 display IF bandwidth
WFM FM 220 kHz
NFM FM 15 kHz
AM AM 6 kHz
LSB LSB 3 kHz
USB USB 3 kHz
CW CW 3 kHz
AUTO AUTO Depends upon bandplan
&Note: The AR5000 does not have a specific legend for WFM, IF bandwidth beyond 30 kHz
becomes WFM.
IF output
The AR5000 IF output setting is automatically configured when the SDU5500 & AR5000 communicate
for the first time, thus overwriting any manual setting.
Step adjust
The step adjust facility does not operate with the AR5000 when step-up or step-down is activated from
the SDU5500.
Attenuator
The attenuator selects 0dB or -10dB, -20dB cannot be selected. The relationship between attenuator
and CENTRE FREQUENCY of the SDU5500 is as follows:
Centre frequency Attenuator On Attenuator Off
Below 1000 MHz (1GHz) 10dB 0dB
1000 MHz and above 0db (ignored) 0dB
Passive band scope
Should you prefer to operate the AR5000 from it’s own front panel, it is possible to configure the
SDU5500 for “Other’ companion radio and use the display unit as a band scope only. The Centre
Frequency will then always be displayed as 10.7 MHz but an OFFSET will be displayed making the
measurement of interesting traces possible.
4-2 Configuration of the AR3000A companion radio
Operation is possible with the AR3000A receiver. However a small modification is required in order to
provide a suitable 10.7 MHz IF output from the AR3000A. The modification requires special skills and
proper tools, some suppliers offer the AR3000A with this modification already carried out. Please
contact your supplier for technical assistance, failing this contact your closest AOR distributor:
Japan: AOR Ltd, 2-6-4 Misuji, Taito-Ku, Tokyo 111-0055, Japan
Tel: [phone] Fax: [phone]
e-mail: [email protected] www.aorja.com
Europe: AOR (UK) Ltd, 4E East Mill, Bridgefoot, Belper, Derbys DE56 2UA, England
Tel: [phone] Int’l: [phone] Fax: [phone] Int’l: [phone]
e-mail: [email protected] www.demon.co.uk/aor
America: AOR USA INC., 20655 S. Western Ave, Suite # 112, Torrance, CA 90501, USA
Tel: [phone] Fax: [phone]
e-mail: [email protected] www.aorusa.com
Section 4-1, 4-2

18
&Note: Although the earlier AR3000 (not AR3000A) may be modified to provide a 10.7 MHz IF
output, the microprocessor is not capable of communicating with the SDU5500, this limits its
effectiveness.
The RS232 baud rate of the AR3000A is set to 4800bps at the factory. However a ‘dip switch’ is
provided on the reverse of the AR3000A microprocessor / display PCB, tucked in the corner directly
behind the x10 TUNING button. There are two switches in this PCB area, the momentary action switch
is for CPU reset (do not touch it), the slide switch is for baud rate control. Remove the lower case of the
AR3000A (2 screws next to the front feet and 2 screws on the rear cabinet, use the correct size cross-
head screwdriver). The switch will currently be pushed toward the edge of the PCB (4800bps), slide it
toward the centre of the PCB (9600bps). The AR3000A will need to be switched off / on for the change
to take effect.
&Note: Although the AR3000A will operate satisfactorily with the SDU5500, stable operation of the
AR3000A at 9600bps is not guaranteed.
• Connect a suitable power supply using the d.c. lead provided. Ensure the correct polarity is
observed, the stripe signifies positive. (In certain market areas, a suitable power supply may be
provided).
• Connect the 9-pin to 9-pin connection lead between the RX CTR socket of the SDU5500 and
REMOTE socket of the AR3000A, an RS232 adapter from 9-pin to 25-pin will be required or procure
/ make up a suitable lead (see section 2-2 item 2 of this manual for pin-out information).
• Connect a 50 OHM BNC patch lead between the RF IN socket of the SDU5500 and the IF OUT
socket of the AR3000A (following modification of the receiver).
Cold start
It is important that the AR3000A is switched on FIRST, press the POWER switch of the AR3000A so
that the display appears on the radio.
Place the AR3000A into REMOTE mode by sliding the rear REMOTE switch upward, the legend “RMT”
confirms operation on the front panel of the AR3000A receiver.
Now switch on the SDU5500. The first time the SDU5500 is switched on, or whenever power is
removed from the SDU5500, a COLD START sequence needs to be followed. This involves selecting
the required receiver via the SDU5500 companion radio configuration menu. As long as power is not
removed from the SDU5500 (even though it may be switched off with the power feed still connected), the
SDU5500 will remember which companion radio is in use.
&Note: The SDU5500 CPU draws a very small current for backup purposes even though the
SDU5500 power switch is off.
The SDU5500 LCD will display various details. Under the item “RX” (third line down from the top left of
the LCD), “Other” radio will be displayed with the CF (centre frequency) of 10.7 MHz. Ensure that
menu item “1” is displayed in the lower left corner of the LCD, if not use the PREV (previous) and
NEXT keys. Press RX to display the COMPANION RADIO configuration menu.
Section4-2

19
Use the spin wheel dial to highlight “AR3000A” then press . The legend “AR3000A Connected” will
briefly be displayed then the CF readout will display the current receive frequency of the AR3000A and
the RX readout will confirm AR3000A. Should any fault occur in connection with the AR3000A at this
stage, the SDU5500 CPU will identify the receiver as “Other” being connected. In this case check the
AR3000A baud rate setting (which should be 9600bps) and connection lead.
Warm Start
Once the SDU5500 has been configured for the AR3000A receiver following a cold start (or any other
receiver in use), it will not be necessary to enter the receiver details again as long as the SDU5500
remains connected to power (presuming that you wish to continue using the same receiver type)... even
after the SDU5500 has been switched off and back on again.
Cold start / Hot start
The initial display which appears on the screen after switching on depends on whether the SDU5500 has
remained connected to a power supply since last use. When the cold start is performed (if power has
been removed), the SDU5500 will start with menu page 1 while menu page 4 will appear when the
SDU5500 is hot-started. Either way, shuttling from page-to-page is possible.
General operational notes
&Note: The AR3000A will now be operated from the front panel of the SDU5500, receive mode,
frequency, attenuator etc may be controlled. All controls of the AR3000A will be locked while in
REMOTE mode.
The minimum specified tuning step size when used with the SDU5500 is 50 Hz , any digits below 50 Hz
will be ignored, the acceptable step sizes being in the range 50 Hz to 999.95 kHz inclusive.
Step adjust
The step adjust facility does not operate with the AR3000A when step-up or step-down is activated from
the SDU5500.
Passive band scope
Should you prefer to operate the AR3000A from it’s own front panel, it is possible to configure the
SDU5500 for “Other” companion radio and use the display unit as a band scope only. The Centre
Frequency will then always be displayed as 10.7 MHz but an OFFSET will be displayed making the
measurement of interesting traces possible.
4-3 Configuration of an ICOM companion radio
Operation is possible with a number of ICOM wide band receivers. Depending upon the model, the
ICOM optional CT17 (RS232/CIV) converter may be required.
Models supported
R7100 CT17 required
R8500 Direct RS232
R9000 CT17 required
The following set-up is required: Baud rate 9600 bps
Frequency data 5 Byte
Transceive ON
Address default IC-R7100 34h
IC-R8500 4Ah
IC-R9000 2Ah
Section 4-2, 4-3

20
4-3-1 Example set-up for the ICOM IC-R7100 receiver
Step 1. For transceive ON
On the ICOM receiver, press and hold both “3” and “ENT” keys and switch the power switch ON.
Switch the receiver OFF again.
Step 2. For baud rate of 9600
On the ICOM receiver, press and hold both the “5” and “ENT” keys and switch the power switch ON.
Switch the receiver OFF again.
4-3-2 Example set-up for the ICOM IC-R8500 receiver
Set the R8500 by accessing the ICOM initial set mode as per page 30 of the ICOM operating manual.
Set the baud rate to 9600 and address to 4Ah. No interface is required.
The receiver must be configured and switched On before the SDU5500 in order to provide a valid
connection via the RS232.
&Note: The output level of the ICOM receiver(s) is about 10 - 15dB below that of the AOR receiver(s)
and may be more liable to AGC effect as signals reach the centre of companion radio passband.
•Connect a suitable power supply to the SDU5500 using the d.c. lead provided. Ensure the correct
polarity is observed, the stripe signifies positive. (In certain market areas, a suitable power supply may
be provided).
•When using an IC-R8500, connect an RS232 lead between the receiver and RX CTR socket of the
SDU5500 (see section 2-2 item 2 of this manual for pin-out information). If using the IC-R7100 or
IC-R9000, connect and power the optional ICOM CT17 interface.
•Connect a 50 OHM patch lead between the RF IN socket of the SDU5500 and the IF OUT socket of
the receiver (ICOM use a phono socket, the input of the SDU5500 uses a BNC).
Cold start
It is important that the companion radio is switched on FIRST.
Now switch on the SDU5500. The first time the SDU5500 is switched on, or whenever power is
removed from the SDU5500, a COLD START sequence needs to be followed. This involves selecting
the required companion radio via the SDU5500 configuration menu. As long as power is not removed
from the SDU5500 (even though it may be switched off with power still connected), the SDU5500 will
remember which companion radio is in use.
&Note: The SDU5500 CPU draws a very small current for backup purposes even though the
SDU5500 power switch is off.
The SDU5500 LCD will display various details. Under the item “RX” (third line down from the top left of
the LCD), the ICOM radio type will be displayed. Ensure that menu item “1” is displayed in the lower
left corner of the LCD, if not use the PREV (previous) and NEXT keys. Press RX to display the
companion radio configuration menu.
Section 4-3-1, 4-3-2