AOR AR800 Operating Manual

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(frequencies such as 1.215 MHz = 1215 kHz).  If signal strength appears weak,
try rotating the receiver as the bar aerial is directional.
The internal ferrite bar aerial should provide adequate results in city and
high population areas or when visiting airshows which operate a
commentary service on medium wave.  Better results may be achieved
by using an external aerial.
It is not possible to further increase sensitivity on medium wave firstly due to
the up-conversion receive circuit employed (which is required for high quality
VHF-UHF reception) and secondly due to the potential noise from the
microprocessor and LCD driver which are located close to the ferrite aerial
(being a compact hand-held design).
Aerial attenuator
An aerial attenuator system allows selection of 0dB or 10dB.  This is especially
useful in reducing the potential for breakthrough when using external aerial
systems and for achieving optimum audio quality for SSB and short wave
operation.
Do remember, if considering the use of an external aerial, there will be a
greater chance of signal overload and breakthrough.  While this will not
damage the receiver in average use, it may degrade the receive performance
due to the effects of “signal mixing”.
VHF - UHF discone aerials
Ideally, separate aerials should be employed for each frequency or band of
interest.  Of course, except for government listening stations this is totally
impractical.  For this reason most people choose an externally mounted
discone aerial such as the AOR DA3000 aerial.  The DA3000 has a usable
coverage of 25 to 2000 MHz.
Shortwave long wire aerials
For the shortwave bands a different type of aerial will be required.  The most
common form is the random long wire, please see sections 22 & 23 on aerials
and propagation for further information.
Aerial Tuning Units (ATU)
An ATU can improve the selectivity of any shortwave receiver when connected
to long wire aerials.  This valuable extra selectivity is achieved by the ATU
rejecting out of band signals enabling the receiver to “single out” one band of
frequencies while rejecting potentially strong unwanted transmissions.
An ATU is usually constructed in a small box with about two or three controls
on the front panel.  One disadvantage however is the need to constantly retune 
						

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the ATU when changing frequency.  An ATU of this type has no active circuitry
so is known as a passive device.
Active desktop loop aerials
Usually designed for the shortwave bands (such as the AOR LA320). Loop
aerials have the advantage of small size when compared to long wire aerials
and being within easy reach of the operator it can be rotated to provide
directivity.  The circuitry offers a small level of gain with the advantage of
selectivity similar to an ATU.
For further information please refer to sections 22 & 23 of this manual
regarding aerial and earth systems.
(5) Controls and functions
The AR8000 receiver is housed in an attractive grey plastic cabinet.  Controls
for operation are located on the top, front and left hand side of the cabinet.
Top Panel
5-1 Aerial (antenna) input
The aerial input is via a high quality BNC 50 OHM socket.  The standard
supplied 16cm rubber whip should be connected to this point and provide good
result across most of the receiver’s frequency coverage. 
						

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5-2 EAR - Earphone / speaker connection
This 3.5mm mono socket permits connection to an external earphone, headset
or speaker of 8 OHM impedance or greater.  When this earphone socket is
used, the internal speaker will be automatically disconnected.
5-3 DIAL - tuning control / selector
The DIAL control is prominently located on the top of the
cabinet for ease of use.  This control changes the received
frequency up and down in whatever step increment is selected and operates as
a “selector” when entering certain data though menus.  This type of rotary
control is often referred to as the “VFO”.
Being a mechanical device, it is not uncommon for operations to be
occasionally missed and this does not constitute a fault (unless excessive).
5-4 SQ - squelch control
The squelch control is used to eliminate unwanted background
noise when monitoring a normally inactive frequency and is
used by the AR8000 microprocessor to determine when a channel is “active”
(busy).  The receiver cannot scan or search when the background noise is
present.
The squelch control requires careful setting to achieve optimum operating
performance.  Rotate the control clockwise until the background noise just
disappears (threshold),  this is the most sensitive setting of the control.  In
practice the control is usually rotated a little further clockwise beyond the
threshold point to prevent the receiver from stopping on noise or very weak and
unreadable signals.
If the control is rotated too far clockwise then weaker signals will be totally lost
and only local strong signals will be heard.
When the squelch control is rotated anticlockwise so that background noise is
audible, the squelch is referred to as being “OPEN”.  In a similar manner, when
the squelch control is rotated clockwise so that the background noise is muted,
the squelch is referred to as being “CLOSED”.
The squelch is not usually used when listening to short wave transmissions
due to the relatively high short wave background noise levels nor in WFM
mode.  The usual setting for the control when listening to short wave or WFM
is fully anticlockwise (squelch open).
Note:  Even when the squelch is fully CLOSED a low level background noise
may still be audible.  This is because the receiver’s audio amplifier circuit is
permanently operational in order to provide fast search/scan rates and an
efficient squelch opening characteristic.  This phenomenon is common with
other hand-held receivers on the market today. 
						

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5-5 PWR / VOL - On/Off switch and volume control
The combined volume control and power switch is located on
the top face of the cabinet.  This control is used to set the required
audio output from the receiver.  When rotated fully clockwise the volume is at
maximum, when rotated fully anticlockwise the volume is reduced to minimum.
At the fully anticlockwise position the power On/Off switch is activated with a
“click”.
Front panel
5-6 Liquid Crystal Display (LCD) - dot matrix
The AR8000 uses a revolutionary high contrast new dot matrix LCD.  Due to its
mechanical construction the LCD is best viewed from directly in front of the
receiver, a fairly wide viewing angle is maintained to the left and right hand
sides but is quickly reduced from below and particularly from above the
display.
The LCD has four lines of eleven character positions
each of which consists of 5 x 8 pixel segments.  A full
test pattern may be displayed by holding the [0] key
while switching the receiver On until the sign-on
welcome message has ended. To remove the test
pattern simply switch the receiver Off/On.
The dot matrix display provides a more conventional
format of number than the conventional seven segment LED/LCD format,
compare the numbers 0, 4, 7 etc.  Alphanumeric comments are also available
in menus to ease programming and identification of memory and search
banks.  Graphical information may also be displayed for signal meter and band
scope.
Attractive green rear illumination of the LCD (and keypad /  side panel) is
switchable for use in locations of low level lighting.
The LCD will provide frequency readout to hundreds of Hz (last digit on the
right) although the receiver is capable of tuning in smaller steps of 50 Hz.
5-7 Keypad
The front keypad comprises of twenty press keys laid in a grid four horizontal
and five vertical.  The keys are multi-function and are used to input frequency
and other operational data in conjunction with the side panel [FUNC] function
key and [DIAL].
Attractive green rear illumination of the front keypad, side panel and LCD is 
						

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switchable for use in locations of low level lighting.
The  basic  operational description of each key is as follows:
[SRCH] - search key
When first pressed initiates the search process and “SRCH” is displayed at the
top left of the LCD.
When [SRCH] is pressed a second time during search, the SEARCH process
is cancelled and the current search frequency is left as a single frequency
readout on the LCD.  This can be useful should you wish not to have 2-VFO
display but wish for a single frequency display...  just press [SRCH] twice while
searching.
If the search process had stopped on an “active” frequency when  [SRCH]
was pressed for the second time, the process would be forced to continue
searching passed the busy frequency.
When in SEARCH mode, the display legend “SRCH” appears on the LCD.
If the sequence [FUNC] [SRCH] is keyed while in search mode the receiver
enters the “SET SEARCH” menu where search banks may be linked and
unlinked.
While in search mode and stopped on an interesting active (busy) frequency,
press [FUNC] [2VFO] to transfer the busy frequency to the “active” (top) VFO
and revert to VFO mode.
[SCAN] [M.R] - scan / memory recall key
When pressed the first time initiates memory recall, the display legend “M.RE”
appears on the LCD.  The numeric keypad may then be used to recall a
specific memory channel or the [DIAL] rotated to scroll through the contents.
To transfer a memory channel to VFO press the [ENT] key.
When [SCAN] is pressed a second time (this means pressing while “M.RE” is
displayed), the receiver enters memory SCAN mode.  When
SCAN mode has been entered, the display legend “SCAN” appears on the
LCD.
When [SCAN] is pressed while in SCAN mode (“SCAN” displayed), the SCAN
process is cancelled and the current SCAN frequency is left on the LCD.
If the scan process had stopped on an “active” channel when [SCAN] was
pressed for the second time, the process would be forced to continue scanning
passed the busy channel.
If the sequence [FUNC] [SCAN] is keyed while in SCAN mode the receiver
enters the “SET M-SCAN” menu where memory banks may be linked and
unlinked.
While in scan mode and stopped on an interesting busy channel,  press
[FUNC] [2VFO] to transfer the busy channel to the “active” (top) VFO and 
						

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revert to VFO mode.
[2-VFO] [A=B] - twin VFO / equalise memory /
manual search key
The AR8000 receiver has a 2 VFO system being identified as “A” and “B” on
the LCD to the left of the frequency readout.  The term VFO historically means
“Variable Frequency Oscillator” and today refers to a tunable data store which
contains frequency, mode, channel step, step offset and attenuator informa-
tion.
Both VFO frequencies are displayed in parallel format on the LCD one above
the other.  The “active” VFO (the one which is currently receiving) is displayed
on the second line and the “stand-by” VFO on the third line below.
When the AR8000 is in a programming mode other than 2VFO such as
SEARCH, SCAN or DATA ENTRY, this key places the set into 2VFO mode.
The display legend “2VFO” appears at the top left hand corner of the first line
of the LCD.  The same line will indicate whether the active VFO has the
attenuator switched On signified by the letter “A” to the right of “2VFO”.  The
top right hand corner of the LCD indicates the current mode (AM, NFM, WFM,
USB, LSB, CW) of the active VFO.
The second line of the LCD displays the ACTIVE VFO frequency.
The third line of the LCD displays the STAND-BY VFO frequency.
The fourth line of the LCD indicates whether the active VFO squelch is open
using the legend “S”, to the right is the signal strength presented as a vertical
bar graph.  The stronger the signal then the larger the graph, if there is no
signal present the fourth line will be blank.  It is quite common for the first
three signal meter segments to appear due to background band noise
even when no signal is present.
If the [2VFO] key is pressed while in 2VFO mode, the active and stand-by VFO
change positions.  i.e. VFO A becomes stand-by and VFO B active and visa
versa whenever the [2VFO] key is pressed.
If the sequence [FUNC] [2VFO] is keyed while in 2VFO mode the receiver
equalises the data in both VFOs so that their contents are identical to the
active VFO (top VFO).  Both VFO displays will appear identical.  This is
particularly useful when quickly setting up a manual search.
If the [2VFO] key is pressed and held for more that one second, the receiver
enters MANUAL SEARCH.  The frequency of VFO A and VFO B must be
different or no search will take place.  If the mode and channel step size are
different in VFO and VFO B then the active VFO data will be used to form the
parameters for search.
When MANUAL SEARCH mode is entered the display legend “MANU SRCH”
appears on the third line of the display.
Should the receiver find an interesting busy channel, press [ENT] to save the
data into a memory channel.  Please refer section 14 FREQUENCY PASS 
						

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should a permanently busy channel be encountered.  The UP and DOWN keys
may be used to force the receiver to continue searching from a busy channel
and to reverse the direction of search.
While in search or scan modes and stopped on an interesting busy channel,
press [FUNC] [2VFO] to transfer the busy channel to the “active” VFO and
revert to VFO mode.
To return to 2VFO mode, press the [2VFO] key.
Should you prefer only a single frequency to be displayed press [SRCH]
[SRCH] while searching or press [SRCH] [ENT] if stopped on a busy
frequency..
[UP>] - UP / move key
This key is used to force the receiver to continue search / scan from a busy
channel and to reverse the direction of search / scan should the receiver be
tracking downward.  The key will also act as an upward tuning control just like
DIAL.
The key is used to select menu options under certain circumstances.
The key may also be used to backspace delete incorrect frequency entry
during the input sequence via the numeric keypad.  It may also be using in
conjunction with the [FUNC] key to edit the active VFO frequency.
[DOWN
						

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[2] [B] [STEP]  Numeric 2 / Bank B / STEP key
This key acts as a numeric 2 when entering frequencies via the keypad.
In search, scan and memory modes this key is used to identify bank B/b.
If the sequence [FUNC] [2] is keyed, the tuning STEP size may be
selected.
[3] [C] [MODE]  Numeric 3 / Bank C / MODE key
This key acts as a numeric 3 when entering frequencies via the keypad.
In search, scan and memory modes this key is used to identify bank C/c.
If the sequence [FUNC] [3] is keyed, the receive MODE may be selected.
[4] [D] [PRI CH]  Numeric 4 / Bank D / Priority operation
This key acts as a numeric 4 when entering frequencies via the keypad.
In search, scan and memory modes this key is used to identify bank D/d.
If the sequence [FUNC] [4] is keyed, the receive PRIORITY channel is
activated / deactivated as a toggle.  The legend “P” appears on the top line of
the LCD to signify that priority channel watch has been activated.
If the sequence [FUNC] then hold [4] for more than one second is keyed,
the “SET PRI CH” set priority channel sub menu is activated.  The priority
channel may be chosen (which bank / number) with sampling time and
accompanying text.  Once a memory channel has been selected for priority,
its data is held in a special priority store so that the informationwill
remain intact even if the original memory channel data is later revised.
[5] [E] [S SCAN]  Numeric 5 / Bank E / Select Scan key
This key acts as a numeric 5 when entering frequencies via the keypad.
In search, scan and memory modes this key is used to identify bank E/e.
If the sequence [FUNC] [5] is keyed, SELECT SCAN will be activated.  The
legend “SEL” appears at the top left of the LCD to indicate select scan
activation.  Select scan only scans those specific channels which have been
identified (tagged) using the  [FUNC] [PASS] select scan procedure.  This is
very useful to allow the rapid selection of a mixture of memory channels
irrespective of memory banks for specific scanning applications.  Press [2VFO]
to cancel SELECT SCAN and return to 2VFO mode. 
						

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[6] [F] [S PROG]  Numeric 6 / Bank F / Search program
This key acts as a numeric 6 when entering frequencies via the keypad.
In search, scan and memory modes this key is used to identify bank F/f.
If the sequence [FUNC] [6] is keyed, the SEARCH PROGRAM menu will be
activated.  The legend “SRCH PROG” appears on the top line of the LCD to
indicate activation.  The data programming or  reprogramming of search banks
may be input through this menu.
While in VFO and search program (menu step size input), the [PASS] key
adds the legend “+” indicating STEP OFFSET which is a useful facility for
following unusual offsets such as a 25 kHz bandplan with 12.5 kHz offset.
[7] [G] [B SCP]  Numeric 7 / Bank G / Band scope
This key acts as a numeric 7 when entering frequencies via the keypad.
In search, scan and memory modes this key is used to identify bank G/g.
If the sequence [FUNC] [7] is keyed while in single VFO frequency display or
two VFO frequency display, the BAND SCOPE will be activated to check for
adjacent channel occupancy.  This bar graph spectrum display uses the whole
eleven horizontal positions of the third line of the LCD (five channels either side
of the centre frequency).  The stronger the signal then the higher the bar graph.
The band scope channel spacing is determined by the receive mode (NFM,
USB etc).
When the [DIAL] is turned or every five seconds the display will be updated.
This can be a useful feature if the “exact” frequency of a specific service is not
known.  There will be a brief interruption to the receive station (centre
frequency) every five seconds as the display is updated.
To deactivate the bandscope, repeat the key sequence [FUNC] [7] or press the
[2VFO], [SRCH] or [SCAN] keys.
[8] [H] [EDT CH]  Numeric 8 / Bank H / Edit memory channel
This key acts as a numeric 8 when entering frequencies via the keypad.
In search, scan and memory modes this key is used to identify bank H/h.
If the sequence [FUNC] [8] is keyed the edit options menu and sub menus
may be accessed.  Initially the legend “SET EDIT-CH” is displayed on the first
line of the LCD.
Edit mode enables memory data to be changed (edited) & data of two memory
channels to be swapped (exchanged).