Lotek BC03 User manual

Lotek Biotracker Receiver User’s Manual Page 1
BIOTRACKER
RADIO RECEIVER
User's Manual

Page 2 Lotek Biotracker Receiver User’s Manual
Contents
Quick Start Guide................................................................................................. 4
Descri tion of receiver o eration ......................................................................... 4
Basic Functions ................................................................................................. 4
Frequency Mode................................................................................................ 4
Channel Mode................................................................................................... 4
Storing Frequencies in Channels .......................................................................... 5
Scanning Mode ................................................................................................. 5
To Panel Controls ............................................................................................... 6
Power ........................................................................................................... 6
LCD Backlight ................................................................................................ 6
U /Down Arrows ............................................................................................ 6
Mode Selection............................................................................................... 6
Tuning Resolution ........................................................................................... 6
Digital Gain/Volume Control Keys...................................................................... 6
Scanning ....................................................................................................... 7
Store in Memory............................................................................................. 7
Change MHz .................................................................................................. 8
Delete........................................................................................................... 8
Numeric Keys................................................................................................. 8
Acce t .......................................................................................................... 8
Cancel .......................................................................................................... 8
Liquid Crystal Dis lay (LCD)................................................................................ 9
Signal Strength Dis lay ................................................................................... 9
Battery State Indicator.................................................................................... 9
Front Panel Connectors and Controls..................................................................... 10
Gain Control Knob ........................................................................................ 10
Battery Charger and External Power Socket...................................................... 10
Charging LED............................................................................................... 10
Antenna in ut .............................................................................................. 11
Head hones Socket ...................................................................................... 11
Serial Port (RS232)....................................................................................... 11
Ste -by-ste instructions .................................................................................... 12
Changing frequency......................................................................................... 12
Storing frequencies to memory (channels) .......................................................... 13
Scanning........................................................................................................ 15
Receiver Use ..................................................................................................... 17
Tracking in wet weather ................................................................................... 17
Batteries ........................................................................................................ 17
Trouble-shooting................................................................................................ 18
Charging Problems .......................................................................................... 18
Battery cover bolts .......................................................................................... 18
Using the serial ort ........................................................................................... 19
Glossary ........................................................................................................... 20
Biotracker S ecifications ..................................................................................... 22
Summary S ecifications Table........................................................................... 22
Full S ecifications Table ................................................................................... 23
S ecification ................................................................................................ 23
Frequency Bands .......................................................................................... 23
Sensitivity ................................................................................................... 23
Selectivity ................................................................................................... 23
Gain Control Range....................................................................................... 23
Channels ..................................................................................................... 23
Scanning ..................................................................................................... 24
Weight ........................................................................................................ 24
Water roofing .............................................................................................. 24
Frequency Stability ....................................................................................... 24
Tuning ........................................................................................................ 25

Lotek Biotracker Receiver User’s Manual Page 3
Battery life................................................................................................... 25
External ower su lies ................................................................................. 25
Back-light on LCD ......................................................................................... 25
Regulatory Com liance........................................................................................ 25
Location of In uts, Out uts and Controls ............................................................... 26
APPENDIX A: ADDITIONAL INFORMATION.............................................................. 27

Page 4 Lotek Biotracker Receiver User’s Manual
Quick Start Guide
Before first use, we recommend you ut the Biotracker on charge. The battery is fully-
charged when the receiver is manufactured, but rechargeable batteries self-discharge
slowly over time and after any eriod of storage will not be at full ca acity.
Description of receiver operation
The receiver has three modes: Frequency, Channel and Scan.
Frequency Mode: Frequency is set directly via the numeric key ad or arrow keys.
Channel Mode: Channels holding stored frequencies are selected via the numeric
key ad or arrow keys. There are 256 channels.
Scan Mode: The receiver ste s in numerical sequence through all channels or
selected channels only.
Basic Functions
• To turn the receiver on and off hold [ON/OFF] down for at least a second.
• To toggle between Frequency and Channel Mode (shown by ‘F’ or ‘C’ in bottom right
corner of dis lay) ress [F/C].
• [X] cancels the current o eration.
• [

] enters the current number (channel, frequency etc) or com letes the current
o eration.
• [DEL] deletes the character at current cursor osition. To delete the contents of a
channel in Channel Mode hold the button down for more than a second.
• The key with the light bulb symbol toggles the dis lay back-light on and off. The light
switches off automatically after about 4 minutes.
• To adjust receiver gain, use the keys with louds eaker symbols. The gain level (00 to
99) is dis layed next to the mode indicator on the bottom row of the LCD. Gain can
also be adjusted (u to the limit shown in the dis lay) using the gain knob. The knob
does not change the gain level dis layed on the LCD.
• Signal strength is dis layed on the to line of the LCD as a horizontal bar gra h, and
the eak signal value is dis layed on the to right. The eak value is held on the
dis lay for 1 second or u dated if another signal is received sooner.
Fre uency Mode
• In Frequency Mode ‘F’ is dis layed in the bottom right corner of the dis lay.
• Ty ing a number enters the kHz frequency units (numbers after the decimal oint).
Press [

] to set the frequency or [X] to cancel and revert back to the revious
frequency.
• To change the MHz frequency (numbers before the decimal oint) ress [MHz].
Enter the MHz frequency and ress [

] to set or [X] to cancel.
• The u /down arrows tune the frequency one ste at a time, at the current tuning
resolution (1 kHz or 0.1 kHz).
• The tuning resolution is toggled between 1 kHz and 0.1 kHz by the key
marked [.000 / .0000].
Channel Mode
• In Channel Mode ‘C’ is dis layed in bottom right corner of dis lay.
• The u /down arrows ste through stored channels in the receiver’s memory.
• Channels can also be recalled by entering a channel number. Press [

] to set
or [X] to cancel.
• To delete the contents of a channel, ress [DEL] for a second or more.

Lotek Biotracker Receiver User’s Manual Page 5
Storing Fre uencies in Channels
• Start in Frequency mode and tune to the frequency to be stored
• Press [Store] to dis lay the last used channel on the to line of the dis lay
• Choose a channel using the u /down arrow keys, or enter a channel number
followed by [

].
• Press [Store] to save the frequency to the channel dis layed on the to line. The
receiver will then be in Channel Mode on the chosen channel.
Scanning Mode
• Press [SCAN] to enter Scanning Mode. Two o osing curved arrows are shown on
the bottom right of the dis lay. The to line shows the scan interval in seconds.
• Choose a scan interval by using the arrow keys or ty ing a number (u to 999).
Press [

] to acce t.
• Press [

] again to dis lay channels on to line of the dis lay. Channels that are
selected for scanning show ‘SC’ in the to right of dis lay.
• Toggle channel selection status (‘SC’) on/off by ressing [

]. Scroll through channels
using the arrow keys or ty e a channel number followed by [

] to see other
channels.
• To select all channels for scanning, ress [DEL]. Pressing [DEL] again deselects all
channels without affecting individual channel selection status (‘SC’). When all
channels are selected for scanning, ‘AC’ is dis layed.
• To start scanning ress [SCAN].
• To sto scanning and return to the mode and frequency settings rior to scanning
ress [X].
• To sto scanning and return to Channel Mode with last channel scanned ress
[SCAN].

Page 6 Lotek Biotracker Receiver User’s Manual
Top Panel Controls
This section ex lains in detail the function of individual keys.
Power
Hold this key down for one second or more to switch the receiver on or off.
When the receiver is switched on it returns to the state it was in when it was
last switched off. It remembers mode, digital gain level, ste size and
frequency or channel. All memory contents are also retained.
LCD Backlight
This key switches the LCD back-light on and off. The back-light increases
receiver ower consum tion (and reduces battery life) by around 50%. To
conserve ower if the light is accidentally switched on, the light switches off
automatically after about 4 minutes.
Up/Down Arrows
These keys are used to change frequency or channel, de ending on which mode
the receiver is in.
When in Frequency Mode (‘F’ dis layed in bottom right of LCD), the frequency
dis layed on the bottom row of the LCD is changed in either 0.1 kHz or 1kHz
ste s. Pressing the key marked [.000/.0000] toggles between the ste sizes
(tuning resolution).
In Channel Mode (‘C’ dis layed in bottom right of LCD), the arrow keys ste through
occu ied channels dis layed on the bottom row of the LCD. Em ty channels are not
dis layed. After ressing [STORE], the u /down keys ste through all channels
dis layed in the to row of the LCD, including em ty ones.
In Scan Mode (two o osing curved arrows dis layed in bottom right of LCD), and when
scan interval is dis layed in the to row of the LCD, the u /down keys change the scan
interval. After setting the scan interval, the u /down keys ste through occu ied
channels. Em ty channels are not dis layed.
Mode Selection
This toggles between Frequency Mode and Channel Mode. When returning from
Channel Mode to Frequency Mode the frequency dis layed is that of the last
channel selected. The default tuning resolution (ste size) is set to 0.1 kHz.
Tuning Resolution
This key toggles between dis laying the frequency to the nearest 0.1 kHz (four
decimal laces) or to the nearest 1 kHz (three decimal laces). It o erates only
in Frequency Mode.
Digital Gain/Volume Control Keys
The keys with louds eaker symbols control the radio frequency (RF) gain and
audio gain (volume) of the receiver. The u er key increases gain and the
lower one reduces it. The gain level is indicated by the number between 0 and
99 in the bottom right of the LCD, immediately before the mode symbol.
These are known as ‘digital gain keys’ because they set gain in discrete ste s.
Gain can also be controlled using a knob on the front of the receiver. The knob controls
gain in an analogue fashion within the limits set by digital keys gain (i.e. u to the level
shown on the LCD). It does not change the number displayed in the LCD. Setting
the gain to 99 (maximum) using the digital keys enables the knob to cover the entire
gain range.

Lotek Biotracker Receiver User’s Manual Page 7
generally the digital keys are used for setting gain to a articular, re eatable level
(dis layed on the LCD). For normal tracking situations, where it is not necessary to
know the exact gain level, the knob allows both faster and finer control of gain.
Scanning
This key uts the receiver into Scan Mode. The to row of the LCD dis lays
‘INTERVAL’ and a number between 001 and 999. This is the eriod in seconds
the receiver dwells on each selected channel when scanning. The number can
be entered directly via the numeric key ad, or increased/decreased using the arrow
keys. When the desired interval is dis layed, ress [

] to set it.
Once the scan interval has been set, the LCD to row dis lays occu ied channels and
indicates whether they are selected for scanning. The information dis layed is
frequency, channel number and, for channels that are selected, the letters ‘SC’ or ‘AC’.
These indicate whether selected channels (SC) or all channels (AC) are to be scanned.
If a channel is not selected for scanning, only the frequency and channel number are
dis layed. When scanning starts, these channels will be excluded. To select or deselect
a channel, ress [

] which toggles channel selection. Do not ress [

] to deselect a
channel, as this cancels Scan Mode. To toggle the selection/deselection of all channels
(AC) ress [DEL]. Use the arrow keys to ste through channels for selection.
When the channels to be scanned have been chosen, ressing [SCAN] starts the
receiver scanning. The bottom row of the LCD dis lays the frequency and number of the
channel currently being scanned, the gain level and the symbol for scan mode (curved
o osing arrows). The to line of the LCD dis lays signal strength and ‘AC’ or ‘SC’,
de ending on whether all channels (AC) or selected channels only (SC) are being
scanned.
To cancel Scan Mode during scanning, ress [SCAN], which returns to Channel Mode
with last channel scanned, or [

], which returns to the mode and frequency settings
rior scanning.
Store in Memory
When ressed in Frequency Mode or Channel Mode this key dis lays the last
used channel on the to row of the LCD. The channel number can be set either
with the arrow keys, or by entering a number directly from the numeric key ad.
If entered from the key ad, [

] must be ressed to set the channel. Pressing [STORE]
a second time uts the currently dis layed frequency on the bottom row into the channel
dis layed on the to row. The receiver is then returned to Channel Mode with the new
channel dis layed in the bottom row.
The main use for [STORE] is to add new channels or change frequencies in existing
channels. Some ty ical sequences are shown below to illustrate this.
To add a new frequency to a new channel:
1. In Frequency Mode, tune to the frequency you wish to store in a channel.
2. Press [STORE] to dis lay a channel on the to row of the LCD.
3. Select the channel in which you want the frequency to the stored (either using the
arrow keys or by direct entry via the numeric key ad followed by [

]).
4. Press [STORE] again to set the frequency in the chosen channel and automatically
switch to Channel Mode with the new channel dis layed.
To change the frequency of an existing channel:
1. In Channel Mode select the channel to be changed.
2. Press [F/C] to change to Frequency Mode.

Page 8 Lotek Biotracker Receiver User’s Manual
3. Change the frequency (either using the arrow keys or by direct entry via the numeric
key ad followed by [

])
5. Press [STORE] to dis lay the channel on the to row of the LCD.
6. Press [STORE] again to set the new frequency in the channel and automatically
switch back to Channel Mode with the new frequency dis layed.
Change MHz
This key allows the MHz frequency to be changed in Frequency Mode. After
ressing [MHz] the first laceholder of the MHz frequency will flash and a new
3-digit number can be inserted from the numeric key ad. After inserting 3
digits the cursor moves to the first decimal lace and the kHz frequencies can also be
changed if required. Pressing [

] at any time selects the new frequency. Pressing [

]
cancels any changes and returns to the revious state.
If a number below than the lower frequency limit or above the u er frequency limit is
entered, an ‘OUT OF RANGE’ message is dis layed on the to row of the LCD. Enter a
valid frequency or ress [

] to return to the revious one.
Delete
The delete key has three se arate functions.
The main function, in Channel Mode, is to delete the contents of a channel. To do this,
dis lay the channel to be deleted, then hold the [DEL] key down for 1 second.
Alternatively, ress [STORE] to dis lay a channel on the to row of the LCD. Dis lay
the channel you want to delete and ress [DEL] to delete it and return to Channel Mode.
The second function of the delete key is to delete characters under the cursor during
frequency or channel editing via the numeric key ad.
The third, and least intuitive, function of [DEL] is to toggle the selection/deselection of
all channels for scanning in scan mode (AC). When selecting channels for scanning,
[

] toggles selection of individual channels (dis laying either SC or blank after
frequency and channel number in the to row of the LCD), whereas [DEL] toggles
between AC and SC or blank. When AC is shown, all channels are selected for scanning.
Pressing [DEL] returns all the channels to their revious state (SC or blank).
Numeric Keys
The numeric key ad is used to enter channels or frequencies.
When entering channel numbers, new digits are inserted in the right-hand lace-holder
and shifted left if further characters are added. This is to eliminate the need to enter
leading zeros.
When entering frequencies, the cursor starts under the left-hand laceholder and moves
right as new number are added.
Accept
This key is equivalent to [ENTER] on a com uter keyboard. It is used to acce t
any changes being made via the numeric key ad.
Cancel
This is the ‘Cancel’ Key. Pressing it during any editing o eration returns the
receiver to the state it was in before the editing o eration began. Pressing [

]
in Scan Mode cancels scanning and returns the receiver to its revious mode.
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Lotek Biotracker Receiver User’s Manual Page 9
Li uid Crystal Display (LCD)
The LCD has two rows with 16 character laces er row. The diagrams below show the
osition of information dis layed in different modes.
LCD Functions in Frequency Mode or Channel Mode
LCD Functions in Scanning Mode
Signal Strength Display
The Lotek Biotracker Receiver dis lays signal strength in two ways: using a bar gra h
and a number. Both indicators are dis layed on the to line of the LCD. The system
res onds to ulses over 10 ms long and above a threshold, so under normal
circumstances noise is ignored. The dis lay is held for 1 second after triggering
(otherwise ulses would be too short to see). If the dis lay is constantly being triggered
by noise, the ulses are likely to be missed.
The dis lay can be changed by adjusting the gain. If there is too much noise and it is
triggering the dis lay, turn the gain down. Similarly, reduce gain if the signal is causing
the bar gra h to swing full scale (and the number dis layed is 99).
Battery State Indicator
The em ty battery symbol in the to right of the LCD indicates when the battery needs to
be recharged. When the battery is OK this symbol is NOT shown; it only a ears when
the battery has about 10% of its ca acity remaining. There is no ‘full battery’ symbol.
Selection of
channels for
scanning
Channel to
be scanned
All
channels
Selected
channels
Channel
not selected
Fre uency in MHz
0.1 kHz
resolution In Channel Mode
only. 001 to 256
Signal Strength
Bar Chart
1 kHz
resolution
Gain
(01 to 99)
Signal Strength
Battery Low
Relative scale
(01 to 99)
Mode
Channel
Number
Channel
Mode
Scanning
Mode
Frequency
Mode

Page 10 Lotek Biotracker Receiver User’s Manual
Front Panel Connectors and Controls
Gain Control Knob
Receiver gain is controlled by two keys (marked with louds eaker symbols) on the
key ad and by a knob on the front of the box. The key ad controls are digital and set
gain to a level shown in the LCD as a whole number between 0 and 99. The knob also
controls gain, but on a continuum between zero and the value shown in the LCD. The
knob does not change the gain level number dis layed on the LCD.
Setting gain to 99 using the key ad allows the full gain range to be controlled by the
knob. Setting digital gain to a lower level revents higher gains being accessible via the
knob, and gives finer control over the available gain range. The main benefit of using
the knob to control receiver gain is that it is quicker to move through the gain range.
The otentiometer under the gain control knob is hermetically sealed, as is its hole in the
receiver box. Unlike analogue controls on most electronic equi ment, it is com letely
water roof.
Battery Charger and External Power Socket
Charging must be done in an ambient tem erature between 5 and 35°C. This is because
there is a thermal cut-out in the charging circuit to revent over-charging of the battery
cells (over-charging cells can damage them). The thermal cut-out threshold is set to
50°C, but the heat generated by the charging rocess can cause this threshold to be
reached in ambient tem eratures above 35°C.
The charging state is shown by an LED next to the charging socket. It flashes red during
battery charging and steady green when charging is com lete.
The receiver will not be harmed if the external ower su ly is left attached after
charging is com lete, but still it is good ractice not to leave the ower su ly connected
for longer than necessary.
Only the s ecial NiMH 4A battery ack su lied with the receiver can be charged inside
the receiver. The receiver revents any other form of battery being connected to the
internal charging circuit. This is mainly to safeguard against charging non-rechargeable
(i.e. rimary) cells, because if charged they may ex lode!
If other rechargeable cells are used (i.e. with the AA battery holder su lied), they need
to be charged inde endently with a se arate AA-size battery charger.
Charging LED
This LED flashes red during battery charging and steady green when charging is
com lete.

Lotek Biotracker Receiver User’s Manual Page 11
Antenna input
The connector is a standard BNC ‘bayonet’ socket with an im edance of 50 ohms.
Headphones Socket
This is a 3.5mm stereo jack socket designed for a matching stereo jack lug. The
head hones su lied with the receiver have 32 ohm s eakers. These are standard
ersonal stereo head hones. Head hones with 8 ohms s eakers can also be used,
though they increase the ower consum tion. A mono jack lug can be used, but the
sound will be quieter.
The internal s eaker cuts out when head hones are used. However, we can su ly a
s ecial ada ter lead, if you would refer the s eaker to continue to sound.
The battery will last longer when head hones are used instead of the internal s eaker,
and weaker signals can be heard using head hones. Therefore we recommend the use
of head hones whenever ossible.
If required, a s ecial lead with an ‘in-line’ volume control can be su lied to enable
volume to be controlled inde endently of receiver gain. This is mainly to enable signal
loudness to be adjusted without affecting the signal strength indicator. It is not
necessary to use this lead to get the best erformance from the receiver. However, for
tracking very owerful tags at close range it may be useful to further reduce signal level.
Please note that it is not necessary for the gain to be on maximum to get the best
receiver sensitivity (i.e. to hear the weakest signals). When using head hones, set the
gain to a level which is comfortable, not on maximum. Receiver sensitivity starts to
reduce below a gain level of about 60; above this there is no advantage other than to
overcome extraneous noise (e.g. when not using head hones).
Serial Port (RS232)
The serial ort enables receiver gain, frequency and channel to be controlled by a
com uter via a serial connection. The receiver is wired for a straight-through cable to
the PC (no cross-over of Tx and Rx lines). The use of the serial link is ex lained later in
this manual. USB ada tors are available for com uters with no serial ort.
The wiring is shown below (9-way ‘D’ connector, viewed from outside the box)
Pin No. Function
1 Not used
2 Tx
3 Rx
4 Not used
5 Ground
6 – 9 Not used
The serial data rotocol is as follows:
1200 baud
1 start bit
8 data bits
1 sto bit
no arity checking
no handshaking
1
2
6
3
7
4
8
5
9

Page 12 Lotek Biotracker Receiver User’s Manual
Step-by-step instructions
This section of the manual ex lains ste -by-ste how to use the main functions of the
receiver. The functions covered are:
• Changing frequency
• Storing frequencies to memory channels
• Deleting channels
• Scanning
Changing fre uency
Normally when entering a new frequency in Frequency Mode the three laces to the left
of the decimal lace (the MHz value) do not need to be changed.
Therefore you need only to use the u -down arrow keys
OR…
Enter the frequency from the numeric key ad then
If you wish to change the entire frequency, then ress before entering the
MHz frequency from the numeric key ad.
Press when the desired frequency is dis layed.
Using the arrow keys the frequency will change in ste s of either 1 kHz or 0.1kHz (.001 /
.0001 MHz).
The ste size (tuning resolution) is toggled by ressing
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Lotek Biotracker Receiver User’s Manual Page 13
Storing fre uencies to memory (channels)
The receiver has 256 memory channels to which you can save frequencies.
Initial Conditions
The receiver needs to be in Frequency Mode, and set to
the frequency you wish to store.
Ste 1
Press to dis lay the last used channel
on the to row.
Ste 2
Use to select the channel in which you want to
store the frequency.
OR…
Enter the channel number from the numeric key ad then
Ste 3
Press to save the frequency in the chosen channel.
The receiver will revert to Channel Mode with the stored
channel selected.
Software to enable channel frequencies to be u loaded via a serial or USB ort from a PC
is available.
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Page 14 Lotek Biotracker Receiver User’s Manual
Deleting Channels
Initial Conditions
The receiver needs to be in Channel Mode.
Ste 1
Use the arrow keys to select the channel which you want to delete.
OR…
Enter the channel number from the numeric key ad then
Ste 2
Press and hold for 1 second or more to delete the contents of the channel.
This will set the channel frequency to ‘000.0000’, but the channel will still be dis layed.
When another channel is selected (e.g. via the arrow keys) the em ty channel will be
removed.
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9

Lotek Biotracker Receiver User’s Manual Page 15
Scanning
The receiver has a Scanning Mode in which selected channels are automatically ste ed
through in sequence at a user-definable time interval. There is no facility to
automatically detect signals in this mode (unlike an amateur radio ‘scanner’).
Initial Conditions
The receiver can be in either Frequency Mode or Channel Mode.
The frequencies to be scanned should already be stored in memory.
Ste 1
Press to dis lay the scanning interval
(in seconds) on the to line of
the dis lay.
Ste 2
Use to select the interval (in seconds, 1 - 999).
OR…
Enter the interval from the numeric key ad then
Ste 3
Press to dis lay channels on the to line of the dis lay.
Ste through the channels using the arrows
Select or deselect individual channels using
This toggles the channel selection and
shows the selection state in the to right of
the dis lay (SC = channel selected for scanning, or blank = channel not selected).
Use to select or deselect all channels at once. The individual selection status
of each channel is not affected by ‘all channel’ deselection.
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9

Page 16 Lotek Biotracker Receiver User’s Manual
The following LCD diagrams show the characters dis layed for the different selection
states:
Individual channel not selected
Individual channel selected
All channels selected
Ste 4
When the channels to be scanned have been selected, ress to start the
scanning rocess.
When only selected channels are being
scanned the to line of the dis lay shows ‘SC’.
When all channels are being scanned the to
line of the dis lay shows ‘AC’.
Ste 5
Press to sto scanning and enter Channel Mode with the receiver set to the
last channel scanned.
Alternatively, to sto scanning and enter Channel Mode with the receiver
set to the channel used when the receiver was last in Channel Mode, ress

Lotek Biotracker Receiver User’s Manual Page 17
Receiver Use
Tracking in wet weather
You do not need to rotect this receiver from the rain. The membrane key ad on the to
anel is com letely water roof, as is the battery com artment lid. All front anel
controls and connectors are sealed on the inside of the receiver box so that water can
not reach the receiver electronics. When they are not in use, the o en sockets
(head hones, serial ort and charger) should have covers fitted to revent water
entering them. S are covers are included with the receiver, and more can be su lied
on request.
If any of the o en sockets get wet, lease dry them out in air (or with a hair dryer) as
soon as ossible.
Batteries
The em ty battery symbol in the to right of the LCD indicates when the battery needs to
be recharged. When the battery is OK this symbol is NOT shown. It only a ears when
the battery has about 10% of its ca acity remaining. There is no ‘full battery’ symbol.
The receiver has a variety of ower su ly o tions to suit the needs of any radio-tracking
roject. A art from the external ower su ly, there is an internal battery which can
take a number of forms. As su lied, the receiver is fitted with a battery ack that can
be recharged from any 12V 500mA DC su ly via the external ower socket. This
battery ack contains four ‘A’-size Nickel Metal-Hydride (NiMH) cells built in a single
block with a re-settable ‘ oly-switch’ and tem erature-sensing thermistor to revent
short-circuit damage and over-charging. It will run the receiver for about 28 hours on a
single charge, and it takes about 10 hours to charge from a com letely discharged state.
When facilities for recharging are not available, the 4A battery ack can be re laced by a
holder for four AA cells. The cells used in this holder can be either rimary (non-
rechargeable) or rechargeable NiCads or NiMH cells. If rechargeable AA cells are used,
they have to be taken out of the receiver for charging. As a safety feature – to revent
accidental charging of rimary cells which may ex lode – only the 4A battery ack
su lied with the receiver can be recharged in situ. During battery ack charging the
ambient tem erature must be between 5 and 35°C. The battery ack may not charge
fully outside these tem eratures.
If you are using the receiver for many hours each day, and have access to a charging
ower su ly (e.g. mains electricity or a car battery) we recommend that you use the
rechargeable 4A battery ack. If you do not have access to a charging su ly, then you
have the choice of rimary cells, or rechargeable cells that have to removed from the
receiver for re lacement or recharging. The main factors to consider when deciding
whether to use rimary or rechargeable cells are: 1) rechargeable cells do not last as
long as rimary cells, and 2) rechargeable cells self-discharge at a high rate and thereby
lose their ca acity even if not used. If the receiver is used infrequently or for only a
short eriod (e.g. for a few hours er week) it is better to fit rimary cells. Using
rechargeable cells reduces waste.
Remove the battery if the receiver is to be stored for more than 3 months, because the
circuitry draws a very small amount of current even when switched off, and it is good
ractice because of the risk of leakage from exhausted rimary cells. Rechargeable
batteries that have been stored for 3 months or more should be recharged before use.
This a lies even if the battery was fully charged after it was last used, because
rechargeable batteries have a high self-discharge rate.
The receiver memory is retained indefinitely even when the receiver has no battery.

Page 18 Lotek Biotracker Receiver User’s Manual
Trouble-shooting
Charging Problems
There are some s ecial cases where charging may be roblematic. The battery in a new
receiver has been charged only once or twice and may not yet have reached its full
ca acity. As a result, for the first few charge-discharge cycles, the receiver may not run
for quite as long as ex ected. Similar roblems may occur if the receiver has been
stored for a long time and the battery is dee ly discharged. This may also result in the
battery a arently not charging ro erly (i.e. the green light comes on too soon,
wrongly indicating that the battery is fully charged).
To overcome these charging roblems, charge the receiver re eatedly (three or four
times), with an interval of about 30 minutes between charges. There is no need to
discharge the battery between each charging session. Sim ly un lug the charger when
the green light comes on, wait half an hour, then lug it in again.
Battery cover bolts
A few users have re orted loosening of the bolts retaining the battery com artment lid.
We believe this may be caused by the heads of the bolts rubbing on clothing. We
rovide s are bolts with each new receiver and we will su ly a limited number of further
re lacements free of charge.
To revent the loss of bolts we recommend they are checked eriodically to ensure they
remain tight. We are trying to find a long-term solution to this roblem, but in the
meantime, if the bolts on your receiver continue to become loose, we suggest covering
them with insulating ta e.
Please do not over-tighten the bolts, nor use thread-locking com ounds to kee the bolts
in lace.

Lotek Biotracker Receiver User’s Manual Page 19
Using the serial port
The receiver should be connected to a PC via its serial ort (RS232, or ‘COMM’ Port) then
switched on and set to Frequency or Channel Mode. The PC sends messages to it via this
serial link, and the receiver re lies. If the message is a command, the receiver re lies
with “OK” (as an ASCII code), whereas if the message is a query, the receiver sends data
corres onding to the query ty e (i.e. frequency, channel number or gain). The command
and query formats are detailed below. Serial to USB converters are available (with their
own installation software) for com uters with no serial ort.
Commands
sf###.####x Set Fre uency
Sets the receiver to Frequency Mode and to the frequency
‘###.####’, which must be a number in the range 138.0000 to
173.9999. The data are in ASCII format and are usually sent as a
string. For exam le, if the frequency to be set is 150.1234 MHz,
the string “sf150.1234x” would be sent to the PC serial ort. The
receiver will res ond by returning ASCII “OK” to the host PC.
sc##x Set Channel
Sets the receiver to Channel Mode and to channel ‘##’, which must
be a two byte hex number corres onding to the wanted channel in
the range 0000h (0) to 0100h (256). The left byte (sent first) is the
least significant byte (LSB) and the right byte is the most significant
byte (MSB). Usually the data are sent as the ASCII characters
re resented by the numbers. For exam le, if the desired channel is
256, the two byte number will be 0100h (the hex equivalent of
decimal 256). The LSB (00h), should be sent first, and the MSB
(01h) second. Using a BASIC rogramming language, such as MS
Visual Basic, the message sent to the serial ort would be “sc” &
CHR(0) & CHR(1) & “x”. The receiver will res ond by returning
ASCII “OK” to the host PC.
sg#x Set Gain
Sets the gain level of the receiver, where # is a 1 byte number
corres onding to the gain level setting and can be in the range 00h
(0) to 63h (99). As ex lained above for channel setting, the data
byte is usually sent as the ASCII character re resented by it. The
receiver will res ond by returning ASCII “OK” to the host PC.
Queries
fx Query Fre uency
The receiver transmits its current frequency setting via the serial
link to the host PC in the format ###.#### where # are ASCII
numeric characters re resenting the frequency e.g. “150.1234”
cx Query Channel
The receiver transmits its current channel setting via the serial link
to the host PC in the format ## ,where ## is a 2 byte number
corres onding to the channel and can be in the range 0000h (0) to
0100h (256). The byte sent first is the LSB followed by the MSB.
e.g. 01h 00h is channel 1.
gx Query Gain
The receiver transmits its current gain level via the serial link to the
host PC in the format # ,where # is a 1 byte number corres onding
to the gain level setting and can be in the range 00h (0) to 63h
(99).

Page 20 Lotek Biotracker Receiver User’s Manual
Glossary
Analogue
Variable on a continuous scale (cf. Digital).
Back-light
The light that illuminates the dis lay for tracking at night.
Bar graph
Shown on the to line of the dis lay.
Battery
A ower su ly com rising a number of cells, usually connected in series. To get greater
voltage cells are wired together in series to make the battery.
Cell
The individual units com rising a battery. Can also be used alone (i.e. not as art of a
battery), if their voltage is adequate for the equi ment being owered. Cells have a
fixed out ut voltage de ending on their chemistry (e.g. Nickel Cadmium – NiCad – cells
develo 1.2V). In common arlance a cell is often called a battery. See also battery.
Channel
A location in memory holding a frequency and other information about the frequency
(e.g. whether it is selected for scanning). Channels in Biotracker are numbered from 1
to 256.
dBm
A measurement unit of ower. In this document it refers to radio-frequency conducted
or radiated signals. It is a ratio measurement on a logarithmic scale indicating the
strength of a signal relative to 1 milliWatt (1 mW):
dBm = 10 log(P) where P is signal ower in mW
Some ty ical measurements:
10 dBm = 10 mW Only the largest radio tags are as owerful as this.
0 dBm = 1 mW Reference ower level for dBm.
-40 to 0 dBm = 0.1 uW to 1 mW Range of ower levels that includes most small tags.
Digital
In discrete ste s (cf. Analogue).
Dwell time
The eriod of time that the receiver s ends on each channel while scanning, sometimes
called the ‘scan interval’.
Gain
The amount of am lification within the receiver. In some receivers the overall system
gain is s lit between radio frequency (RF) gain (or just ‘gain’) and volume. In the
Biotracker, the gain control changes both RF and volume in arallel.
LCD
Liquid Crystal Dis lay (referred to here as ‘the dis lay’)