Hartcran House, 231 Kenton Lane, Harrow, Middlesex, HA3 8RP, England
Tel: +44 (0) 20 8909 9595, Fax: +44 (0) 20 8909 2233, www.radiometrix.com
Issue 1, 31 July 2012
QPT1
VHF Narrow Band FM 2 Watt multi channel
The QPT1 transmitter module offers a 2 watt
RF output VHF radio link, in either a robust
aluminium extruded casing, or a smaller
footprint PCB mounted shield can. This unit
is ideally suited to applications where
existing lower powered transmitters provide
insufficient range. The QPT1 transmitter is a
multi-channel, narrowband design, suitable
for licensed and unlicensed VHF allocations,
FCC part 90 operation, and the 2M amateur
band. Together with a matching LMR1 or
RX1M receiver a one-way radio data link can
be achieved over a distance of well over
10km (with a suitable antenna)."
Features
Figure 1: QPT1-173-5-12k5-FCC-EAS
Compliant with FCC part 90
PLL synthesizer with TCXO
Data rates up to 5 kbps for standard module
Usable range over 10km
Re-programmable via RS232 interface
Applications
Amateur radio
MURS units
Industrial telemetry and telecommand
High-end security systems
APRS systems
Vehicle data up/download
ROV/machinery controls
Technical Summary
Operating frequency: 144.000 - 144.775 (25KHz steps)
Any 2MHz segment in 135 - 175MHz
16 channels selected by parallel interface
or 32 channels by serial command
Transmit power: 2 W (+33dBm) nominal (1 watt version available)
Supply range: 12V (11 – 15V)
Current consumption: 550mA typ.
Data bit rate: 5kbps max
Size: 68 x 55 x 15mm (pcb mounted version)
83 x 64 x 30 mm (extrusion case version)
(dimensions do not include connectors)
Radiometrix Ltd
QPT1 Data Sheet
page 1
Figure 2: QPT1 block diagram
Radiometrix Ltd
QPT1 Data Sheet
page 2
Figure 3: QPT1 footprint (top view through can)
Pin description (PCB mounted version)
Pin
1
2
3
4
5
Name
Vcc
0V
TXE
TXD
P3
Function
12V DC supply (11-15V). 550mA typ. current drain
Ground
Transmitter enable. Low = ON, open = off. 100K pullup to (raw Vin -4v)
DC coupled input for 3V CMOS logic. Rin=47kΩ
Parallel Channel select MSB
6
7
8
P1
P2
P0
9
0V
Parallel Channel select
Parallel Channel select
Parallel Channel select (LSB) and serial programming/control input
(inverted logic level RS232)
Ground
Notes:
1. No 'modem version' is available, but the PL_ and CX series firmware can be used
2. Parallel port has a 50K pullups to internal 4v rail
3. Caution. The TXD and P0-P3 inputs are not high voltage tolerant. Low voltage logic, or
switches to ground, are required.
4. Overall thermal power dissipation in normal use is around 4 watts, rising to 6-7 watts under
aerial fault conditions.
5. This is a 2 watt output product. Good grounding , good quality aerials, properly mounted,
and a low impedence power supply are required if full performance is to be reliably
obtained. If feasible, we recommend mounting the module, and the board it is on, inside a
metal enclosure, with the RF connctor exiting through a bulkhead. All signal and power
feeds should be filtered and/or decoupled.
Failure to observe these measures can cause modulation distortion ('recirculation' effects)
or instability. Also be aware of the effect that the strong RF fields generated by this device
(and it's aerial) can have upon other adjacent circuitry if this is not properly screened,
filtered or otherwise protected. Regulators, sensitive analogue circuitry, and
microprocessors seem especially interference prone.
6. Two watts of RF at VHF can cause an unpleasant and painful burn. Be careful
7. This design uses the LMT1 100mW transmitter as an internal component
Radiometrix Ltd
QPT1 Data Sheet
page 3
Figure 3: QPT1 footprint (top view through casing)
Pin description (15 way D type connector)
Pin
1
2
3 -8
9
10
11
12
13
Name
TXD
TXE
N/C
0V
P3
P1
P2
P0
14
15
PGM
Vcc
Function
DC coupled input for 3V CMOS logic. Rin=47kΩ
Transmitter enable. Low = ON, open = off. 100K pullup to (raw Vin -4v)
(reserved for future products)
Ground
Parallel Channel select MSB
Parallel Channel select
Parallel Channel select
Parallel Channel select (LSB) and serial programming/control input
(inverted logic level RS232)
True RS232 input (inverter to pin 13)
12V DC supply (11-15V). 550mA typ. current drain
Notes:
1. No 'modem version' is available, but the PL_ and CX series firmware can be used
2. Parallel port has a 50K pullups to internal 4v rail, and 5v transorbs to ground
3. Caution. The TXD and P0-P3 inputs are not high voltage tolerant. Low voltage logic, or
switches to ground, are required.
4. A simple RS232 voltage tolerant transistor inverter connects pin 14 to P0/PGM
5. Overall thermal power dissipation in normal use is around 4 watts, rising to 6-7 watts under
aerial fault conditions.
6. This is a 2 watt output product. Good grounding , good quality aerials, properly mounted,
and a low impedence power supply are required if full performance is to be reliably
obtained.
Be aware of the effect that the strong RF fields generated by this device (and it's aerial) can
have upon other adjacent circuitry if this is not properly screened, filtered or otherwise
protected. Regulators, sensitive analogue circuitry, and microprocessors seem especially
interference prone.
7. Two watts of RF at VHF can cause an unpleasant and painful burn. Be careful
8. This design uses the LMT1 100mW transmitter as an internal component
9. For visual reference, this unit uses an Evatron-type REAS80 extrusion
Radiometrix Ltd
QPT1 Data Sheet
page 4
Serial interface commands
2400 baud RS232. 8 bit data, no parity, 1 start bit, 1 or 2 stop bits.
Serial data is sent to the unit on one of the parallel channel select pins (P0). It is very important
that the unit does not 'decode' switch bounce in ordinary operation as a command string, or
spurious re-writing of the e2prom will result. For this reason the user must send the 16 character
string ENABLESERIALMODE (followed by a carriage return) to fully enable the serial command
mode before sending any of the command strings listed below. Command mode is disabled on
power down, or on reception of a # character. To successfully program the unit, n_txe must be
'low' (active) to enable the unit.
GOCHAN aa
LOAD aa nnnnn
SETPAR
SETSER
RVALUE rrrr
SINGLE nnnnn
<cr>
/
#
Serially select channel aa, where aa is ch0 to ch31
Set value of N register for channel aa, where aa is Channels 0 to 31
Channel selected by 4 bit parallel inputs (ch0 to ch15 only)
Channel selected by most recent GOCHAN operation
Set value for R register
Set value of N for single channel operation.
N value NOT stored in EEPROM
Process entry
Clear all buffers
Disable command mode
aa = a two digit channel number from 00 to 31
nnnnn = synthesizer N register value (up to 65535)
rrrr = synthesizer R register value (up to 16383)
For QPT1 Transmitter:
R=
N TX
f Xtal
=
10MHz
, So R=400
25kHz
f channelspacing
f RF
173.250MHz
=
=
= 6930
f Channelspacing
25kHz
Notes: 1. A pause of at least 50ms must be allowed between command strings (EEPROM
programming time).
2. SINGLE mode does not store the N value in EEPROM. Therefore the unit is
inoperative after a power down until either another valid SINGLE command is
received, or mode is changed by a GOCHAN, SETPAR or SETSER command.
SINGLE mode is intended for frequency agile applications.
Radiometrix Ltd
QPT1 Data Sheet
page 5
Condensed specifications
Frequency
Frequency stability
Channel spacing
Number of channels
Operating temperature
Transmitter
Output power
Peak deviation
TX on switching time
Modulation type
TX modulation bandwidth
Adjacent channel TX power
TX spurious
Supply
Voltage
Current
Inputs
Size
As supplied: 144.000 - 144.775MHz (25kHz steps)
North American: 173.20375 - 173.39625MHz (12.5kHz steps)
154.45625 - 154.47875MHz (12.5kHz steps)
General: any +/-2MHz band in 135-175MHz
±1.5kHz
25kHz (12.5kHz for North America)
16 channels controlled by parallel port
or 32 via serial RS232 interface
-20 ºC to +55 ºC (Storage -30 ºC to +70 ºC)
+33dBm (2W) ±1dB
±3kHz (±1.5kHz @ 12.5kHz channel spacing)
30ms from TXE transition
FSK (F3D)
DC – 5kHz (3V CMOS compatible)
<-37dBm
<-36dBm (no RF output in Standby)
11 – 15V
550mA nominal transmit
<5µA standby (TXE high or floating)
data (CMOS/TTL compatible)
68 x 55 x 15mm (pcb mounted version)
83 x 64 x 30 mm (extrusion case version)
(dimensions do not include connectors)
Interface
User
RF
Recommended PCB hole size
Radiometrix Ltd
9 pin 0.1" pitch header (pcb mounted version)
15 pin D type socket (extrusion case version)
SMA bulkhead connector
1.2mm (pcb mounted version)
QPT1 Data Sheet
page 6
Ordering Information
Part No.
Description
QPT1-144-5
QPT1-144-5-EAS
LMR1-144-5
PCB mounted TX
TX in extrusion case
Receiver
Channel
spacing
25kHz
25kHz
25kHz
Frequency band
(MHz)
144.000 - 146.000
144.000 - 146.000
144.000 - 146.000
QPT1-154-5-12k5-FCC
QPT1-154-5-12k5-FCC- EAS
LMR1-154-5-12K5-FCC
PCB mounted TX
TX in extrusion case
Receiver
12.5kHz
12.5kHz
12.5kHz
154.000 - 156.000
154.000 - 156.000
154.000 - 156.000
QPT1-173-5-FCC
QPT1-173-5-12k5-FCC-EAS
LMR1-173-5-12K5-FCC
PCB mounted TX
TX in extrusion case
Receiver
12.5kHz
12.5kHz
12.5kHz
173.000 - 175.000
173.000 - 175.000
173.000 - 175.000
QPT1-xxx-5
QPT1-xxx-5-12k5
QPT1-xxx-5-EAS
QPT1-xxx-5-12k5-EAS
LMR1-xxx-5
LMR1-xxx-5-12k5
Where xxx is any 2MHz band from 135MHz to-175MHz
FCC Part 90.238 Telemetry frequency channels (12.5KHz spacing)
Channels
CH0
CH1
CH 2
CH 3
CH 4
CH 5
CH 6
CH 7
173MHz band
173.20375
173.21000
173.23750
173.28750
173.31250
173.33750
173.36250
173.39625
154MHz band
154.45625
154.46375
154.47125
154.47875
154.45625
154.46375
154.47125
154.47875
Data sheet links:
http://www.radiometrix.co.uk/dsheets/qpt1.pdf
http://www.radiometrix.co.uk/dsheets/lmt1lmr1.pdf
Radiometrix Ltd
QPT1 Data Sheet
page 7
Radiometrix Ltd
Hartcran House
231 Kenton Lane
Harrow, Middlesex
HA3 8RP
ENGLAND
Tel: +44 (0) 20 8909 9595
Fax: +44 (0) 20 8909 2233
[email protected]
www.radiometrix.com
Copyright notice
This product data sheet is the original work and copyrighted property of Radiometrix Ltd. Reproduction in
whole or in part must give clear acknowledgement to the copyright owner.
Limitation of liability
The information furnished by Radiometrix Ltd is believed to be accurate and reliable. Radiometrix Ltd
reserves the right to make changes or improvements in the design, specification or manufacture of its
subassembly products without notice. Radiometrix Ltd does not assume any liability arising from the
application or use of any product or circuit described herein, nor for any infringements of patents or other
rights of third parties which may result from the use of its products. This data sheet neither states nor
implies warranty of any kind, including fitness for any particular application. These radio devices may be
subject to radio interference and may not function as intended if interference is present. We do NOT
recommend their use for life critical applications.
The Intrastat commodity code for all our modules is: 8542 6000
R&TTE Directive
After 7 April 2001 the manufacturer can only place finished product on the market under the provisions of
the R&TTE Directive. Equipment within the scope of the R&TTE Directive may demonstrate compliance
to the essential requirements specified in Article 3 of the Directive, as appropriate to the particular
equipment.
Further details are available on The Office of Communications (Ofcom) web site:
http://www.ofcom.org.uk/
Information Requests
Ofcom
Riverside House
2a Southwark Bridge Road
London SE1 9HA
Tel: +44 (0)300 123 3333 or 020 7981 3040
Fax: +44 (0)20 7981 3333
[email protected]
European Communications Office (ECO)
Peblingehus
Nansensgade 19
DK 1366 Copenhagen
Tel. +45 33896300
Fax +45 33896330
[email protected]
www.ero.dk