RADIOMETRIX NTX0

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, 02 November 2012
NTX0 / NRX0
27MHz HF Narrow Band FM TX & RX
The 10kHz channel NBFM NTX0 transmitter
and NRX0 receiver operate on the licence
exempt 27MHz SRD HF allocation. These
modules offer a low power, reliable data link
in a Radiometrix SIL standard pin out and foot
print. This makes the NTX0/NRX0 pair ideally
suited to those low power applications where
existing single frequency wideband UHF
modules have insufficient range, and in parts
of the world where other frequency bands are
not appropriate
Figure 1: NRX0-27.095-5
NTX0-27.095-5
Features
Conforms to ETSI EN 300 220-3 (radio) and EN 301 489-3 (EMC) and FCC 95.201-95.225
Standard frequency: 27.095MHz
Data rates up to 5kbps
Usable range over 1km @ 10mW
10/12.5kHz Channel spacing
Feature-rich interface (RSSI, analogue and digital baseband)
Longer range compared to Wide Band FM modules
Applications
Radio Control (R/C) Radio Service under FCC Part 95 subpart C
Radio model control
Telemetry and telecommand
Wireless door entry systems
Simple On/Off switching
In-building environmental monitoring and control
Security and fire alarms
Vehicle/machinery controls
Technical Summary
Transmitter – NTX0
3 stage crystal controlled VCXO
Supply 2.9V - 15V @ 20mA (10mW)
Data bit rate: 5kbps max.
Transmit power: +10dBm (10mW), 50mW (+17dBm) or100mW (+20dBm)
Size: 43 x 15 x 8mm
Receiver – NRX0
Double conversion FM superhet
Supply range: 2.9V - 15V @ 12mA
Data bit rate: 5kbps max.
Receiver sensitivity: -115dBm (for 12dB SINAD)
Adjacent Channel: -60dBm
Blocking: -85dB
Size: 47 x 17 x 8mm
Evaluation platforms: NBEK + SIL carrier
Radiometrix Ltd.,
NTX0/NRX0 data sheet
Page 1
Functional description
The NTX0 transmitter consists of a Frequency Modulated (FM) Voltage Controlled Crystal Oscillator (VCXO)
feeding a two stage amplifier and RF filter. Operation can be controlled by the EN (Enable) line, the
transmitter achieving full RF output typically within 5ms of this line being pulled high. The RF output is
filtered to ensure compliance with the appropriate radio regulations and fed to the 50Ωantenna pin.
The NRX0 module is a double conversion NBFM superhet receiver capable of handling data rates of up to
5kbps. It will operate from a supply of 2.9V to 15V and draws 12mA when receiving. A signal strength (RSSI)
output with greater than 60dB of range is provided. The SIL style NRX0 measures 47 x 17 x 8 mm excluding
the pins.
NTX0 Transmitter
43mm
8mm
32mm
23.5mm
15mm
NTX0
15.24mm (0.6")
1
2
3
4
5
7 holes of 0.7mm dia.
pin spacing 2.54mm (0.1")
6
7
1 = RF gnd
2 = RF out
3 = RF gnd
4 = En
5 = Vcc
6 = 0V
7 = TXD
Figure 2: NTX0 pin-out and dimension
User interface
NTX0 pin
1, 3
Name
RFGND
2
4
5
6
7
Notes:
RF out
EN
Vcc
0V
TXD
1.
2.
3.
4.
5.
Function
RF ground is internally connected to the module screen and pin 6 (0V).
These pins should be directly connected to the RF return path - e.g. coax
braid, main PCB ground plane etc.
50Ω RF output to the antenna
Pull high to enable Transmitter (3V CMOS logic)
2.9 – 15V DC power supply
Ground
DC coupled input (3V CMOS logic). Rin = 100kΩ
EN must not be left floating
Pinout footprint is as NTX2. (Like a TX1, but pcb is longer)
Compatible with LMR0 and NRX0.
TXD is actually a linear input, with self bias to 1.5V
27.095MHz is the default channel.
Radiometrix Ltd.,
NTX0/NRX0 data sheet
Page 2
NRX0 receiver
47mm
8mm
17mm
NRX0
Radiometrix
30.48mm (1.2")
1
2
3
4
5
7 holes of 0.7mm dia pin spacing 2.54mm (0.1")
6
7
1 = RF in
2 = RF gnd
3 = RSSI
4 = 0V
5 = Vcc
6 = AF
7 = RXD
Figure 3: NRX0 pin-out and dimension
User interface – NRX0
NRX0 pin
1
2
Name
RF in
RF gnd
3
RSSI
4
5
6
7
0V
Vcc
AF
RXD
Function
50Ω RF input from the antenna
RF Ground is internally connected to the module screen and pin 4 (0V).
These pins should be directly connected to the RF return path - e.g. coax
braid, main PCB ground plane etc.
Received Signal Strength Indicator with >60dB range.
DC level between 0.5V and 2V
Ground
2.9 – 15V DC power supply (4.1 – 15V for 50 and 100mW version)
500mVpk-pk audio. DC coupled, approx 0.8V bias
Received Data output from the internal data slicer. The data is squared
version of the Audio signal on pin 6 and is true data, i.e. as fed to the
transmitter. Output is "open-collector" format with internal 10kΩpull-up to
Vcc (pin 5). Suitable for bi-phase codes
Notes:
1. Pinout is as NRX1, NRX2 and RX2A receivers
2. Unlike other NRX family radios, the sense of AF, relative to transmitter input, is NOT inverted
3. 27.095MHz is the default channel.
Radiometrix Ltd.,
NTX0/NRX0 data sheet
Page 3
Absolute maximum ratings
Exceeding the values given below may cause permanent damage to the module.
Operating temperature
Storage temperature
-10°C to +60°C
-30°C to +70°C
NTX0
Vcc, TXD (pins 5,7)
En (pin 4)
RF out (pin 2)
-0.3V to +16.0V
-0.3V to +Vcc V
±50V @ <10MHz, +20dBm @ >10MHz
NRX0
Vcc, RXD (pins 7,9)
En, RSSI, AF (pins 4,5,8)
RF in (pin 1)
-0.3V to +16.0V
-0.3V to +Vcc V
±50V @ <10MHz, +13dBm @ >10MHz
Performance specifications: NTX0 transmitter
(Vcc = 3V / temperature = 20°C unless stated)
General
DC supply
Supply voltage for 10mW
TX Supply current @ 10mW
Supply voltage for 50mW
TX Supply current @ 50mW
Supply voltage for 100mW
TX Supply current @ 100mW
Antenna pin impedance
RF
RF centre frequency
Channel spacing
Number of channels
RF power output
RF power output
RF power output
Spurious emissions
Adjacent channel TX power
Frequency accuracy
FM deviation (peak)
Baseband
Modulation type
Modulation bandwidth @ -3dB
Data rate
TXD input level (logic low)
TXD input level (logic high)
Dynamic timing
TX Enable to full RF
Notes:
1.
2.
3.
4.
5.
6.
7.
8.
pin
min.
typ.
max.
units
5
5
5
5
5
5
2
2.9
15
15
15
-
V
mA
V
mA
V
mA
-
3.0
20
5.0
50
5.0
70
50
+9
+16
+19
-
27.095
10
1
+10
+17
+20
-37
±1.5
±2.0
+11
+18
+21
-40
-
MHz
kHz
1
2
2, 8
2, 8
7
-
dBm
dBm
dBm
dBm
dBm
kHz
kHz
0
-
FSK
0
3.0
3
5
-
kHz
kbps
V
V
-
-
5
ms
2
2
2
2
7
7
4.1
4.1
notes
3
4
F3D
NRZ
5
5
Available in 25kHz channel steps on other custom frequencies in the 27MHz band
Measured into 50Ω resistive load.
Total over full supply and temperature range.
With 0V – 3.0V modulation input.
To achieve specified FM deviation.
For 1Vpk-pk signal biased at 1.4V
Complies with spurious emission limits of ETSI EN 300 220-1
For use in USA, Australia, NZ and only for model control in Europe.
The 100mW version is limited to 9v or 25% duty cycle
Radiometrix Ltd.,
NTX0/NRX0 data sheet
Page 4
Performance specifications:
NRX0 receiver
(Vcc = 3V / temperature = 20°C unless stated)
DC supply
Supply voltage
Supply current
RF/IF
RF centre frequency
Frequency accuracy
Channel spacing
RF sensitivity @ 12dB SINAD
RSSI range
Blocking
Image rejection
Adjacent channel rejection
Spurious response rejection
LO re-radiation
pin
min.
typ.
max.
units
7
7
2.9
-
3.0
12
15
-
V
mA
1,6
1, 6
1, 6
1, 6
1, 4
1
1
1
1
1
-45
-45
-65
27.095
±1.5
10
-115
60
85
-70
-
-
MHz
kHz
kHz
dBm
dB
dB
dB
dB
dB
dBm
6
500
0.8
5
3
5
-
kHz
kbps
mVP-P
V
%
Baseband
Baseband bandwidth @ -3dB
Data rate
AF level
DC offset on AF out
Distortion on recovered AF
6
6
6
0
-
Dynamic timing
Power up with signal present
Power up to valid RSSI
Power up to valid AF
Power up to stable data
5, 3
5,6
5, 7
-
3
2
TBA
10
ms
ms
ms
Signal applied with supply on
Signal to valid RSSI
Signal to valid AF
Signal to stable data
1, 3
1,6
1, 7
-
2
1
TBA
5
ms
ms
ms
Time between data transitions
7
0.1
-
TBA
ms
Notes:
1.
2.
3.
4.
5.
notes
1
2
3
2
NRZ
4
5
For 12 dB SINAD, 1KHz mod, 2KHz dev
See applications information for further details.
Exceeds EN/EMC requirements at all frequencies.
For received signal with ±2kHz FM deviation
For 50:50 mark to space ratio (i.e. squarewave).
Radiometrix Ltd.,
NTX0/NRX0 data sheet
Page 5
Applications information
Power supply requirements
Both modules have built-in regulators which deliver a constant 2.8V (4V in 50mW and 100mW version) to
the module circuitry when the external supply voltage is 2.9V or greater (4.1V in 50mW and 100mW
version), with 40dB or more of supply ripple rejection. This ensures constant performance up to the
maximum permitted rail, and removes the need for external supply decoupling except in cases where the
supply rail is extremely poor (ripple/noise content >100mVpk-pk).
Continuous operation of 100mW version above 9V supply is not recommended.
The Enable pin allows the TX module to be turned on or off under 3V logic control with a constant DC supply
to the Vcc pin. The module current in power-down mode is less than 1µA.
The Enable pin should be tied directly to the Vcc pin if this facility is not required.
NTX0 modulation requirements
The module is factory-set to produce the specified FM deviation with a TXD input to pin 7 of 3V amplitude,
i.e. 0V “low”, 3V “high
If the data input level is greater than 3V, a resistor must be added in series with the TXD input to limit the
modulating input voltage to a maximum of 3V on pin 7. TXD input resistance is 100kΩ to ground, giving
typical required resistor values as follows:
Vcc
≤3V
3.3V
5V
9V
Series resistor
10 kΩ
68kΩ
220kΩ
NRX0 Received Signal Strength Indicator (RSSI)
The NRX0 receiver incorporates a wide range RSSI which measures the strength of an incoming signal over
a range of 55dB or more. This allows assessment of link quality and available margin and is useful when
performing range tests.
The output on pin 3 of the module has a standing DC bias of <0.5V with no signal, rising to 2V at maximum
indication.
Typical RSSI characteristic is as shown below:
Fig.6: Typical RSSI response curve
Radiometrix Ltd.,
NTX0/NRX0 data sheet
Page 6
Module mounting considerations
The modules may be mounted vertically or bent horizontal to the motherboard. Note that the components
mounted on the underside of the NTX0 and NRX0 are relatively fragile – avoid direct mechanical contact
between these and other parts of the equipment if possible, particularly in situations where extreme
mechanical stresses could routinely occur (as a result of equipment being dropped onto the floor, etc).
Good RF layout practice should be observed. 50Ω microstrip line or coax or a combination of both should be
used to connect RF pin of the module to RF connector or antenna. It is desirable (but not essential) to fill all
unused PCB area around the module with ground plane.
Variants and ordering information
The NTX0 transmitters and NRX0 receivers are manufactured on 27.095MHz as standard:
NTX0-27.095-5
NTX0-27.095-5-50mW
NTX0-27.095-5-100mW
10mW Transmitter
50mW Transmitter
100mW Transmitter
NRX0-27.095-5
Receiver
Subject to MOQ, other frequency variants can be supplied to individual customer requirements in the 27MHz
licence exempt SRD / model control band. i.e.
10mW
26.957 - 27.283MHz Non-specific Short Range Devices (SRD)
100mW
26.995, 27.045, 27.095, 27.145, 27.195 MHz Model Control
Radiometrix Ltd.,
NTX0/NRX0 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