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
QPX1
Issue 1, 24 October 2014
2 Watt Multi-channel VHF Transceiver
The QPX1 transceiver module offers a 2
watt RF output VHF radio link, in a robust
aluminium extruded casing. This unit is
ideally suited to applications where
existing lower powered transceivers
provide insufficient range. The QPX1 is a
multi-channel,
narrowband
design,
suitable for licensed and unlicensed VHF
allocations, FCC part 90, part 95 (MURS)
operation, and the 2M amateur band.
Figure 1: QPX1-173-5-12k5-FCC-EAS
Features
Compliant with FCC part 90, part 95 (MURS)
High performance double superhet PLL synthesizer
Data rates up to 5 kbps for standard module
Usable range over 10km
Feature-rich interface (RSSI, CD, analogue and digital baseband)
Incorporate a 1200baud dumb modem
Re-programmable via RS232 interface
Applications
Amateur radio
Multi-Use Radio Service (MURS)
Industrial telemetry and telecommand
High-end security systems
APRS systems
Vehicle data up/download
ROV/machinery controls
Technical Summary
Standard operating frequency: 151MHz / 173MHz band FCC allocation (12.5kHz channel)
Any +/-2MHz band in 135-175MHz
8 channels controlled by parallel port or via RS232 interface)
Transmit power: : 2 W (+33dBm) nominal (500mW and 1 watt versions available)
Supply range: 12V (11 – 15V)
Current consumption: 600mA transmit, 30mA receive
Data bit rate: 5kbps max. (standard module)
Receiver sensitivity: -118dBm (for 12 dB SINAD)
Size: 123 x 59 x 30mm (in EAS120 case - excluding connectors)
Radiometrix Ltd
QPX1 Data Sheet
page 1
Figure 2: QPX1 footprint (top view through casing)
8
1
15
9
Figure 3: DB15 connector pin arrangement
User interface: (EAS cased version)
Pin
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
Name
TXD
TXE
AF in
ENABLE
RSSI
AF out
RXD
SQF
0V
P3
P2
P1
P0/PGM
PGM
Vcc
Function
DC coupled input for 3V CMOS logic. Rin=47kΩ
Transmitter enable. Low = ON, open = off. 100K pullup to (raw Vin -5v)
250mVp-p to 2.5V p-p AC coupled input. Variable gain
Overall unit 'on' (high active, high voltage tolerant)
DC level between 0.5v and 2.5v. 60dB dynamic range
200mV p-p audio. DC coupled, approx 1v bias. Muted by squelch
Open collector output of data slicer suitable for Biphase codes
Carrier level squelch. Open collector. ON/low = no signal
Ground
Parallel frequency select inputs. Inverted logic, 10K pullups to 5v
Serial programming/control input (inverted logic level RS232)
True RS232 input (inverter to pin 13)
12V DC supply (11-15V). 550mA typ. current drain
9
NOTE:
1. QPX1 does not invert the sense of the data waveform. There is no resulting in no net link
inversion between two units.
A version with an inversion in the RX data path is also available
2. Carrier detect mutes the AF and DATA outputs. It can be disabled by rotating the level set
trimmer fully CW.
3. There are no pullups on the open collector outputs.
4. The sofware incorporates a 1200baud dumb modem, compatible with that implemented in
TX2M, RX2M, TR2M and SMX2 radios ( i1200 tones and format ).
Radiometrix Ltd
QPX1 Data Sheet
page 2
5. RS232 input pins (14 and 12 ) tolerate true +/- levels. No buffering is required.
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.
Two watts of RF at VHF can cause an unpleasant and painful burn. Be careful.
7. Caution:. The TXD and P1-P3 inputs are not high voltage tolerant. Low voltage logic, or
switches to ground, are required.
8. A simple RS232 voltage tolerant transistor inverter connects pin 14 to PGM
9. Depending on the firmware, some versions use P0-P3 as parallel select. Others use P0 as a
programming input only, and P1-P3 as parallel inputs. Refer to tech support for details.
10. Enable pin (4) may be tied to +Vin
11. Overall thermal power dissipation in normal use is around 4 watts, rising to 6-7 watts under
aerial fault conditions.
12. This design uses the SMX1 mk2 transceiver RF board as an internal component
13. For visual reference, this unit uses an Evatron-type REAS120 extrusion
Figure 4: QPX1 footprint (PCB mounted version)
User interface (PCB mounted version)
Pin
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
Name
GND
PGM
P1
P2
P3
TXD
TXE
GND
Vcc
AF in
ENABLE
RSSI
AF out
RXD
SQF
GND
Radiometrix Ltd
Function
Ground
Programming Input from 5V TTL UART TX (inverted RS232) output
Parallel frequency select inputs. Inverted logic, 10K pullups to 5v
DC coupled input for 3V CMOS logic. Rin=47kΩ
Transmitter enable. Low = ON, open = off. 100K pullup to (raw Vin -5v)
Ground
12V DC supply (11-15V). 550mA typ. current drain
250mVp-p to 2.5V p-p AC coupled input. Variable gain
Overall unit 'on' (high active, high voltage tolerant)
DC level between 0.5v and 2.5v. 60dB dynamic range
200mV p-p audio. DC coupled, approx 1v bias. Muted by squelch
Open collector output of data slicer suitable for Biphase codes
Carrier level squelch. Open collector. ON/low = no signal
Ground
QPX1 Data Sheet
page 3
Modem interface (EAS cased version)
The 'modem' mentioned is a 1200 baud RS232 semi-intelligent unit (Transmit keyed when valid serial data is
present, so no separate TX control needed. Coding in the datastream also permits the receiver to ignore
noise and only output valid serial data) This is a half duplex unit, so collisions between transmitted and
received packets must be dealt with by the user.
Pin
Name
Function
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
NC
TXE
NC
ENABLE
RSSI
AF out
NC
NC
0V
(tba)
MOD RXD
MOD TXD
PGM
PGM
Vcc
Leave open
Open = normal modem operation. Low = constant TX (for test). 10K pullup to 5v
Leave open
Overall unit 'on' (high active, high voltage tolerant)
DC level between 0.5v and 2.5v. 60dB dynamic range
200mV p-p audio. DC coupled, approx 1v bias. Muted by squelch
Leave open
Leave open
Ground
Leave open
inverted "RS232" data out (to inverting buffer like MAX232)
RS232 data input (true). 10K pullups to 5v
inverted version of pin 14
Serial programming/control input (true RS232)
12V DC supply (11-15V). 550mA typ. current drain
Modem interface (PCB mounted version)
Pin
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
Name
GND
PGM
MODTXD
MODRXD
NC
TXD
TXE
GND
Vcc
AF in
ENABLE
RSSI
AF out
RXD
SQF
GND
Radiometrix Ltd
Function
Ground
Programming Input from 2400bps, 5V TTL UART TX (inverted RS232)
1200bps, 8 data bits, None Parity, 1 stop bit, RS232 TXD input
1200bps, 8 data bits, None Parity, 1 stop bit, 5V TTL UART RXD output
DC coupled input for 3V CMOS logic. Rin=47kΩ
Transmitter enable. Low = ON, open = off. 100K pullup to (raw Vin -5v)
Ground
12V DC supply (11-15V). 550mA typ. current drain
250mVp-p to 2.5V p-p AC coupled input. Variable gain
Overall unit 'on' (high active, high voltage tolerant)
DC level between 0.5v and 2.5v. 60dB dynamic range
200mV p-p audio. DC coupled, approx 1v bias. Muted by squelch
Open collector output of data slicer suitable for Biphase codes
Carrier level squelch. Open collector. ON/low = no signal
Ground
QPX1 Data Sheet
page 4
Serial Programming
Serial data is sent to the unit on the programming input PGM (pin 14)
2400 baud at RS232 level. 8 bit data, no parity, 1 start bit, 1 or 2 stop bits, No flow control. All commands
must be in upper case.
To successfully program the unit, 'ENABLE' (pin 4) must be 'high' (active) to enable the unit.
Once 'modem' mode has been selected, the unit locks into serial command mode (and the parallel port pins
have other functions) until a SETPAR command returns the unit to ordinary parallel operation.
Unlike earlier Radiometrix multichannel units, the QPX1 (and USA versions of SMX1) has separate N and R
registers for each channel, on transmit and on receive. In other words, the frequency of each channel is
individually programmed in every mode.
Unless a complex frequency map has been selected, all the R value registers are likely to be programmed
with the same value
Command
GOCHAN a
Function
serial select of channel a (ch0 to 7)
LDTXN a
LDRXN a
LDTXR a
LDRXR a
set value of N for channel a , for transmit
set value of N for channel a , for receive
set value of R for channel a , for transmit
set value of R for channel a , for receive
nnnnn
nnnnn
rrrrr
rrrrr
SETPAR
SETSER
RVALUE rrrrr
SINGLE nnnnn
SETMOD
<cr>
/
#
channel selected by 3 bit parallel input 3
channel selected by most recent 'gochan' operation
set R register value used by SINGLE command
set value of N for single channel operation. N value NOT stored in
e2prom
Enable internal modem. Frequency selected by most recent 'gochan' or
'single'
process entry
clear all buffers
disable command mode
a = a single digit channel number from 0 to 7
nnnnn = a synthesizer N register value, (up to 65535)
rrrrr = the synthesizer R register value, (up to 16383)
ChannelFrequency (inMHz )
10 R
ChannelFrequency (inMHz ) − 21.4
For Receive, N rx =
10 R
f Xtal
10 MHz
R=
=
, So R= 400 (usually)
f channelspacing
25kHz
For Transmit, N tx =
Note:
In 'SINGLE' mode 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 applies a receive frequency offset of 21.4MHz
'Single' mode is intended for frequency agile applications.
A pause of at least 50mS must be allowed between command strings (eeprom programming time)
Radiometrix Ltd
QPX1 Data Sheet
page 5
Condensed specifications
Frequency
Frequency stability
Channel spacing
Number of channels
Supply
voltage
Current
Operating temperature
Size
Spurious radiations
Interface
User
RF
Intended approval
154.45625 - 154.47875MHz (12.5kHz steps) – FCC part 90
173.20375 - 173.39625MHz (12.5kHz steps) - FCC part 90
General: any +/-2MHz band in 135-175MHz
± 1.5kHz
25kHz / 12.5kHz
8 channels (controlled by parallel port or via RS232 interface)
11 - 15V
600mA nominal (800mA max.) transmit
30mA receive
<5uA standby ('enable' pin low)
ο
ο
-10 to +55 C (Storage -30 to +70 C)
in EAS120 case 123 x 59 x 30mm (excluding connectors)
107 x 55.5 x 17mm (PCB mounted version - excluding RF connector)
< 2nW (-57dBm)
15pin D type (extrusion case version)
16 pin 0.1" pitch header (PCB mounted version)
SMA
US 'part 90' approval
EU EN300-220 (dependant on power level)
Transmitter
Output power
TX on switching time
Modulation type
TX modulation bandwidth
Deviation
Adjacent channel TX power
TX spurii
Inputs
2W (+33dBm) +/- 1dB (500mW and 1 watt versions available)
<50 ms (from TXE transition)
FSK (F3D)
DC – 5kHz (CMOS compatible, or analogue AF)
+/- 3kHz (25kHz) or 1.5kHz (12.5kHz)
-37dBm
-36dBm
data (CMOS/TTL compatible)
Receiver
Sensitivity
image / spurious
blocking
adjacent channel
Outputs
Power on to valid audio
Power on to stable data out
-118dBm for 12dB SINAD
-60dB
-84dB
-60 dB
RSSI, carrier detect, audio, data
28ms
50ms (for 50:50 mark / space)
Notes: 1. The data slicer cannot be depended upon for data waveform frequencies below 250Hz
2. When RX is on and a transmitter keys up, again a 50ms period is required to stabilise data output
mark/space. i.e. allow at least 50ms of preamble
FCC Part 90.238 Telemetry frequency channels (12.5KHz spacing)
CHANNELS
CH0
CH1
CH2
CH3
CH4
CH5
CH6
CH7
Radiometrix Ltd
154MHz band
154.45625
154.46375
154.47125
154.47875
154.45625
154.46375
154.47125
154.47875
173MHz band
173.20375
173.21000
173.23750
173.28750
173.31250
173.33750
173.36250
173.39625
QPX1 Data Sheet
page 6
Ordering Information
Part No.
QPX1-154-5-12k5-FCC-EAS
QPX1-173-5-12k5-FCC-EAS
QPX1-xxx-5-EAS
QPX1-154-5-12k5-FCC
QPX1-173-5-12k5-FCC
QPX1-xxx-5
Description
US version in extrusion case
US version in extrusion case
Standard 25kHz channel in extrusion
case
US version as PCB mounted
US version as PCB mounted
Standard 25kHz channel as PCB
mounted
Frequency band (MHz)
154MHz
173MHz
Where xxx is any VHF
frequency with in 135-175MHz
154MHz
173MHz
Where xxx is any VHF
frequency with in 135-175MHz
Data sheet links:
http://www.radiometrix.co.uk/dsheets/qpx1.pdf
http://www.radiometrix.co.uk/dsheets/smx1.pdf
Radiometrix Ltd
QPX1 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
wholeor 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/radiocomms/ifi/
Information Requests
Ofcom
Riverside House
2a Southwark Bridge Road
London SE1 9HA
Tel: +44 (0)845 456 3000 or 020 7981 3040
Fax: +44 (0)20 7783 4033
[email protected]
European Radiocommunications Office (ERO)
Peblingehus
Nansensgade 19
DK 1366 Copenhagen
Tel. +45 33896300
Fax +45 33896330
[email protected]
www.ero.dk