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Functional description
The TX1 transmitter module is a two stage crystal controlled NBFM transmitter
operating between 2.2V and 12V at a current of 9.5mA. At 3V supply it
delivers nominally +10dBm RF output. The SIL style TX1 measures 32 x 12
x 3.8 mm excluding the pins.
|
| The RX1 module is a single conversion
NBFM superhet receiver capable of handling data rates of up to 10kb/s. It
will operate from a supply of 2.7V to 12V and draws 12mA when receiving.
A signal strength (RSSI) output with greater than 80dB of range is provided.
The SIL style RX1 measures 48 x 17.5 x 5.5 mm excluding the pins. |
| |
TX1 transmitter
Fig1: Block diagram
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 |
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| Pin description |
|
Fig.2: TX1 physical dimensions |
| RF gnd |
(pins 1 & 3) |
RF ground, 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.
|
| RF out |
(pin 2) |
| 50W RF output to antenna. Internally
DC-isolated. See antenna section of applications notes for details
of suitable antennas / feeds. |
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| |
| En |
(pin 4) |
| Tx enable.
£0.15V or open-circuit on this pin disables module (current
<1mA), £1.7V
enables module. Input impedance 2MW approxl.
Observe slew rate requirments ( see applications notes). |
| Vcc |
(pin 5) |
| DC +ve supply. Max ripple content
0.1Vp-p. Decoupling is not generally required. |
| OV |
(pin 6) |
| DC supply ground. Internally connected
to pins 1, 3 and module screen. |
| TXD |
(pin 7) |
| DC-coupled modulation input. Accepts
serial digital data at 0V to 3V levels. See applications notes for
suggested drive methods. Input impedance 100kW
nominal. |
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RX1 receiver
Fig.3: RX1 block diagram
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| Pin description |
|
Fig.4: RX1 physical dimensions
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| RF in |
(pins 1 ) |
| 50W RF
input from antenna. Internally DC-isolated. See antenna section of
applications notes for suggested antennas and feeds. |
| RF gnd |
(pins 2&3) |
|
RF ground, 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.
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| En |
(pin 4) |
Rx enable. £0.15V
or open-circuit on this pin disables module (current <1mA),
£1.7V enables module. Input impedance
2MW approxl. Observe slew rate requirments
( see applications notes).
|
| RSSI |
(pin 5) |
Received signal strength indicator
with >80dB range. See applications notes for typical characteristics.
|
| OV |
(pin 6) |
| DC supply ground. Internally connected
to pins 2, 3 and module screen. |
| Vcc |
(pin 7) |
| DC +ve supply. Max ripple content
0.1Vp-p. Decoupling is not generally required |
| AF out |
(pin 8) |
Buffered and filtered analogue output
from the FM demodulator. It has a standing DC bias of 1V and 400mVp-p
baseband signal. Useful as a test point or to drive external decoders
(see applications notes). External load should be >1kW
// <100pF.
|
| RXD |
(pin 9) |
| Digital output from internal data
slicer (squared version of the signal on pin 8). It may be used to
drive external decoders. The data is true data, i.e. as fed to the
transmitter. Output is “open-collector” format with internal 10kW
pullup to Vcc (pin 7). |
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| Absolute maximum ratings |
Exceeding the values given
below may cause permanent damage to the module.
Operating temperature
Storage temperature |
-20°C to +60°C
-40°C to +100°C |
| TXI |
|
| Vcc, TXD (pins 5,7) |
-0.3V to +16.0V |
| En (pin 4) |
-0.3V to +Vcc V |
| RF out (pin 2) |
50V @ <10MHz, +20dBm @ >10MHz |
| |
|
| RX1 |
|
| Vcc, RXD (pins 7,9) |
-0.3V to +10.0V |
| En, RSSI, AF (pins 4,5,8) |
-0.3V to +Vcc V |
| RF in (pin 1) |
± 50V @ <10MHz,+13dBm@>10MHz |
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Performance specifications: TX1 transmitter
(Vcc = 3.0V / temperature = 20°C unless stated) |
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Pin |
Min |
Typ |
Max |
Unite |
Notes |
| DC supply |
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| Supply voltage |
5 |
2.2 |
3.0 |
10 |
V |
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| Supply current |
5 |
|
9.5 |
11 |
mA |
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| RF |
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| RF power output @ Vcc
= 2.2V |
2 |
+4.5 |
+6 |
+7.5 |
dBm |
1 |
| RF power output @ Vcc
³ 2.8V |
2 |
+8.5 |
+10 |
+11.5 |
dBm |
1 |
| Spurious emissions |
2 |
|
-70 |
-55 |
dBc |
1 |
| Frequency accuracy |
|
-2.0 |
0 |
+2.0 |
kHz |
3 |
| FM deviation (peak) |
|
±2.5 |
±3.0 |
±3.5 |
kHz |
4 |
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| Baseband |
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| Modulation bandwidth
@ -3dB |
|
0 |
|
7 |
kHz |
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| Modulation distortion
(THD) |
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|
10 |
15 |
% |
7 |
| TXD input level (logic
low) |
7 |
-0.2 |
0 |
0.2 |
V |
5,7 |
| TXD input level (logic
high) |
7 |
2.8 |
3.0 |
3.2 |
V |
5,7 |
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| Dynamic timing
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| Power-up time (En® full
RF) |
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2 |
5 |
ms |
6,7 |
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| Notes |
| 1. |
Measured into 50W
resistive load |
| 2. |
Exceeds EN/EMC requirements at all
frequencies. |
| 3. |
Total over full supply and temperature
range. |
| 4. |
With 0V – 3.0V modulation input.
|
| 5. |
To achieve specified FM deviation.
|
| 6. |
Dependent upon TXD conditions during
power-up. |
| 7. |
See applications information for
further details. |
|
| |
Performance specifications:
RX1 receiver
(Vcc = 3.0V / temperature = 20°C unless stated) |
 |
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Pin |
Min |
Typ |
Max |
Unite |
Notes |
| DC supply
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| Supply voltage |
7 |
2.7 |
3.0 |
10 |
V |
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| Supply current |
7 |
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12 |
14 |
mA |
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| RF/IF |
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| RF sensitivity @ 10dB
(S+N)/N |
1,8 |
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-119 |
-115 |
dBm |
1 |
| RF sensitivity @ 1ppm
BER |
1,9 |
|
-116 |
-112 |
dBm |
1 |
| IP3 at RF input |
1 |
|
-28 |
|
dBm |
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| RSSI threshold |
1,5 |
|
-127 |
|
dBm |
|
| RSSI range |
1,5 |
80 |
90 |
|
dB |
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| IF bandwidth |
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|
15 |
|
kHz |
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| Image rejection |
1 |
50 |
55 |
|
db |
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| Adjacent channel rejection
|
1 |
50 |
55/60 |
|
dB |
2 |
| Spurious response rejection
|
1 |
70 |
100 |
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dB |
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| LO leakage, conducted
|
1 |
-70 |
-65 |
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dBm |
3 |
| LO leakage, radiated
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-70 |
-60 |
dBm |
3 |
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| Baseband |
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| Baseband bandwidth @
-3dB |
8 |
0.05 |
|
6 |
kHx |
1,4 |
| AF level |
8 |
|
400 |
|
mVp-p |
5 |
| DC offset on AF out |
8 |
0.7 |
1.0 |
1.3 |
V |
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| Distortion
on recovered AF |
8 |
|
1 |
10 |
& |
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| Load capacitance,
AFout / RXD |
8,9
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|
100 |
pF |
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| Dynamic timing |
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| Power up with signal
present |
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| Power up to valid RSSI
|
4,5 |
|
4 |
5 |
ms |
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| Power up to stable data
|
4,9 |
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16 |
20 |
ms |
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| Signal applied with supply
on |
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| Signal to valid RSSI
|
1,5 |
|
0.4 |
0.6 |
ms |
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| Signal to stable data
|
1,9 |
|
4 |
12 |
ms |
6 |
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| Time between data transitions
|
9 |
1.8 |
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0.1 |
ms |
7 |
| Mark : space ratio |
9 |
20 |
50 |
80 |
% |
8 |
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| Notes:
|
| 1. |
See applications information for further
details. |
| 2. |
Typically 55dB @ +25kHz offset, 60dB
@ -25kHz offset. |
| 3. |
Exceeds EN/EMC requirements at all
frequencies. |
| 4. |
Lower limit can be extended to DC
if required, by means of external circuitry. |
| 5. |
For received signal with ±3kHz FM
deviation. |
| 6. |
Typically 4ms for signal at channel
centre, maximum 12ms at ±4kHz RF offset. |
| 7. |
For 50:50 mark to space ratio (i.e.
squarewave). |
| 8. |
Average over 50ms period at maximum
bit rate. |
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Module test circuits
Fig.5: TX1 test circuit
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Fig.6: RX1 test circuit |
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Power supply requirements
Both modules have built-in regulators which deliver
a constant 2.8V to the module circuitry when the external supply voltage
is 2.85V or greater, with 40dB or more of supply ripple rejection. This
ensures constant performance up to the maximum permitted 10V rail and
removes the need for external supply decoupling except in cases where
the supply rail is extremely poor (ripple/noise content >0.1Vp-p).
Note, however, that for supply voltages lower than
2.8V the regulator is effectively inoperative and supply ripple rejection
is considerably reduced. Under these conditions the ripple/noise on the
RX1 supply rail should be below 20mVp-p to avoid problems.
If the quality of the supply is in doubt, it is recommended
that a 10mF tantalum or similar capacitor be
added between pin 7 of the module (Vcc) and ground together with a 10ohm
series feed resistor between pin 7 and the supply rail.
The enable pin allows the module to be turned on or
off under logic control with a constant DC supply to the Vcc pin. The
module current in power down mode is less than 1mA.
NOTE: If this facility is used, the logic control signal must have a slew
rate of 40mV/ms or more. Slew rates less than this value may cause erratic
operation of the on board regulator and therefore the module itself.
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TX1 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”. Reducing the amplitude of the data input from this value (usually
as a result of reducing the supply voltage) reduces the transmitted FM
deviation to typically ±2.5kHz at the lower extreme of 2.2V. The receiver
will cope with this quite happily and no significant degradation of link
performance should be observed as a result. Where the module supply is
greater than 3V a resistor must be added in series with the TXD input
to limit the modulation amplitude to a maximum of 3V on pin 7. TXD input
resistance is 100kW to ground, giving typical
required resistor values as follows:
| Vcc |
Series resistor |
| £3V |
- |
| 3.3V |
10 kW |
| 5.V |
68kW |
| 9.V |
220kW |
It should be noted that conditions on TXD have a significant
effect on the startup time of the module, i.e. the time between En (or
En+Vcc) going high and full RF output being produced. For fastest startup
TXD should either be low or fed with data (preamble etc) for a minimum
of 3ms after En has been asserted. Startup time under these conditions
is typically 50-70% of that obtained if TXD is held high over the same
period.
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Reducing the output power of the TX1
If the TX1-173.250 is to be used for other than industrial/commercial
applications its output power must be reduced to 1mW to comply with type
approval requirements. This is done by inserting a 10dB attenuator network
between the module and the antenna or feed, as follows:
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 |
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Fig.7: 10dB attenuator for TX1
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Keep all tracking around the attenuator network
as short as possible, particularly ground paths, and use matched 50ohm microstrip
lines for input and output connections (track width of 2.5mm if using 1.6mm
thick FR4 PCB). |
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RX1 Received Signal Strength Indicator (RSSI)
The RX1 receiver incorporates a wide range RSSI which
measures the strength of an incoming signal over a range of 80dB or more.
This allows assessment of link quality and available margin and is useful
when performing range tests.
Please note that the actual RSSI voltage at any given RF input level varies
somewhat between units. The RSSI facility is intended as a relative indicator
only - it is not designed to be, or suitable as, an accurate and repeatable
measure of absolute signal level or transmitter-receiver distance.
The output on pin 5 of the module has a standing DC
bias of 0.15V-0.45V (0.25V typ.) with no signal, rising to 0.9-1.3V (1.15V
typ.) at maximum indication. Output impedance is 10kW.
Pin 5 can drive a 100µA meter directly, for simple monitoring.
Typical RSSI characteristic is shown below (this
is for indicative purposes only and is not a guarantee of actual RSSI
characteristics):
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 |
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Fig.8: Typical RSSI response
curve
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To ensure a reasonably fast response the RSSI line has limited internal
decoupling of 11nF to ground. This results in a small amount of audio ripple
on the DC output at pin 5 of the module. If this is a problem further decoupling
may be added at the expense of response speed, in the form of a capacitor
from pin 5 to ground. For example, adding an extra 0.1mF on this pin will
increase the RSSI response time to around 4ms. |
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Expected range
Predicting the range obtainable in any given situation
is notoriously difficult since there are many factors involved. The main
ones to consider are as follows:
- Type and location of antennas in use (see pages
10-12)
- Type of terrain and degree of obstruction of the
link path
- Sources of interference affecting the receiver
- “Dead” spots caused by signal reflections from nearby
conductive objects
- Data rate and degree of filtering employed (see
page 9)
The following are typical examples – but range tests
should always be performed before assuming that a particular range can
be achieved in a given situation:
|
| Data rate |
TX antenna |
Rx antenna |
Environment |
Range |
| 1.2kb/s |
half-wave |
half-wave |
rural/open |
10-15km |
| 10kb/s |
half-wave |
half-wave |
rural/open |
3-4km |
| 10kb/s |
helical |
half-wave |
urban/obstructed |
500m-1km |
| 10kb/s |
helical |
helical |
in-building |
100-200m |
|
Note: that the figure
for 1.2kb/s assumes that the receiver bandwidth has been suitably reduced
by utilising an outboard audio filter/data slicer or similar arrangemetn.
If the RX1 is used “as it is” the range will be similar to that for 10kb/s.
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| |
The TX1 data input is normally driven directly
by logic levels but will also accept analogue drive (e.g. 2-tone signaling).
In this case it is recommended that TXD (pin 7) be DC-biased to 1.2V approx.
with the modulation ac-coupled and limited to a maximum of 2Vp-p to minimize
distortion over the link. The varactor modulator in the TX1 introduces some
2nd harmonic distortion which may be reduced if necessary by predistortion
of the analogue waveform. At the other end of the link the RX1 AF output
is used to drive an external decoder directly.
Although the modulation bandwidth of the TX1 extends down to DC, as does
the AF output of the RX1, it is not advisable to use data containing a DC
component. This is because frequency errors and drifts between the transmitter
and receiver occur in normal operation, resulting in DC offset errors on
the RX1 audio output.
The RX1 in standard form incorporates a low pass filter with a 6kHz nominal
bandwidth. In conjunction with similar filtering in the TX1 an overall system
bandwidth of 5kHz is obtained. This is suitable for transmission of data
at raw bit rates up to 10kb/s. A lower rolloff frequency of around 50Hz
has been chosen for the internal filter and data slicer in order to keep
receiver settling times reasonably fast. This results in a lowest usable
data speed of about 1kb/s for the standard module.
In applications such as long range fixed links where data speed is not of
prime concern, a considerable increase in range can be obtained by using
the slowest possible data rate together with filtering to reduce the receiver
bandwidth to the minimum necessary. The internal data slicer is not suitable
for data having longer than 1.8ms between transitions and in such circumstances
the RX1 audio output can be utilised to drive an external filter and data
slicer.
The RX1 produces an audio output of approximately 400mVp-p at pin 8, but
due to the internal filtering this exhibits a rolloff at low frequencies
giving a reduced output of some 100mVp-p as DC is approached. This rolloff
can be eliminated and a flat response to DC obtained by using an external
RC compensation network, as follows: |
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Fig.9: Audio compensation network
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The output of the network will be flat from DC to
5kHz+. It will have a standing DC bias of 1V approx. and should not be significantly
loaded (input impedance of following stage should ideally be ³1MW).
|
| |
Antennas
The choice and positioning of transmitter and receiver
antennas is of the utmost importance and is the single most significant
factor in determining system range. The following notes are intended to
assist the user in choosing the most effective antenna type for any given
application.
Integral antennas
These are relatively inefficient compared to the larger externally-mounted
types and hence tend to be effective only over limited ranges. They do however
result in physically compact equipment and for this reason are often preferred
for portable applications. Particular care is required with this type of
antenna to achieve optimum results and the following should be taken into
account:
|
| 1. |
Nearby conducting objects such as
a PCB or battery can cause detuning or screening of the antenna which
severely reduces efficiency. Ideally the antenna should stick out
from the top of the product and be entirely in the clear, however
this is often not desirable for practical/ergonomic reasons and a
compromise may need to be reached. If an internal antenna must be
used try to keep it away from other metal components and pay particular
attention to the “hot” end (i.e. the far end) as this is generally
the most susceptible to detuning. The space around the antenna is
as important as the antenna itself.
|
| 2. |
Microprocessors and microcontrollers
tend to radiate significant amounts of radio frequency hash which
can cause desensitization of the receiver if its antenna is in close
proximity. The problem becomes worse as logic speeds increase, because
fast logic edges generate harmonics across the VHF range which are
then radiated effectively by the PCB tracking. In extreme cases system
range may be reduced by a factor of 5 or more. To minimize any adverse
effects situate antenna and module as far as possible from any such
circuitry and keep PCB track lengths to the minimum possible. A ground
plane can be highly effective in cutting radiated interference and
its use is strongly recommended. |
|
A simple test for interference is to monitor the receiver RSSI output voltage,
which should be the same regardless of whether the microcontroller or other
logic circuitry is running or in reset. |
|
| The following types of integral antenna
are in common use: |
Quarter-wave whip.
This consists simply of a piece of wire or rod connected to the module at
one end. At 173MHz the total length should be 410mm from module pin to antenna
tip including any interconnecting wire or tracking. Because of the length
of this antenna it is almost always external to the product casing.
Helical. This is a more compact but slightly less
effective antenna formed from a coil of wire. It is very efficient for its
size, but because of its high Q it suffers badly from detuning caused by
proximity to nearby conductive objects and needs to be carefully trimmed
for best performance in a given situation. The size shown is about the maximum
commonly used at 173MHz and appropriate scaling of length, diameter and
number of turns can make individual designs much smaller.
Loop. A loop of PCB track having an inside area
as large as possible (minimum about 5cm²), tuned and matched with 2
capacitors. Loops are relatively inefficient but have good immunity to proximity
detuning, so may be preferred in shorter range applications where high component
packing density is necessary. |
|
|
Fig.10: Integral antenna configuration
|
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| Integral antenna summary: |
| |
Whip |
Helical |
Loop |
| Ultimate performance |
*** |
** |
* |
| Ease of design set-up |
*** |
** |
* |
| Size |
* |
*** |
** |
| Immunity to proximity effects |
** |
* |
*** |
|
|
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Tamper-proof integral antenna
Where the RX1 is used in alarm applications it may sometimes be necessary
to provide a warning if any attempt is made to remove or disable its antenna.
A typical solution to this problem is as follows: |
| |
 |
|
Fig.11: Tamper proof antenna
arrangement
|
In normal operation the output will have a resistance
to ground of R1+R2. If the antenna is shorted to ground it will show R2
only, and if the antenna is cut it will be open-circuit. R1 and R2 may be
any value over 1kW. All track lengths should be kept to a minimum and the
output may need to be decoupled in some cases to avoid noise being injected
into the antenna from the following circuitry. |
| |
External antennas
These have several advantages if portability is not an issue, and are essential
for long range links. External antennas can be epitomized for individual
circumstances and may be mounted in relatively good RF locations away from
sources of interference, being connected to the equipment by coax feeder.
|
Helical. Of similar dimensions and performance
to the integral type mentioned above, commercially-available helical antennas
normally have the coil element protected by a plastic molding or sleeve
and incorporate a coax connector at one end (usually a straight or right-angle
BNC type). These are compact and simple to use as they come pre-tuned for
a given application, but are relatively inefficient and are best suited
to shorter ranges.
|
| Quarter-wave whip.
Again similar to the integral type, the element usually consists of a stainless
steel rod or a wire contained within a semi-flexible molded plastic jacket.
Various mounting options are available, from a simple BNC connector to wall
brackets, through-panel fixings and magnetic mounts for temporary attachment
to steel surfaces. A significant improvement in performance is obtainable
if the whip is used in conjunction with a metal ground plane. For best results
this should extend all round the base of the whip out to a radius of 300mm
or more (under these conditions performance approaches that of a half-wave
dipole) but even relatively small metal areas will produce a worthwhile
improvement over the whip alone. The ground plane should be electrically
connected to the coax outer at the base of the whip. Magnetic mounts are
slightly different in that they rely on capacitance between the mount and
the metal surface to achieve the same result. A ground plane can also be
simulated by using 3 or 4 quarter-wave radials equally spaced around the
base of the whip, connected at their inner ends to the outer of the coax
feed. A better match to a 50W coax feed can be
achieved if the elements are angled downwards at approximately 45°. |
|
| |
 |
|
fig.12: Quarter wave antenna / ground plane configurations
|
Half-wave.
There are two main variants of this antenna, both of which are very effective
and are recommended where long range and all-round coverage are required
|
| |
| 1. |
The half-wave dipole consists of two
quarter-wave whips mounted in line vertically and fed in the centre
with coaxial cable. The bottom whip takes the place of the ground
plane described previously. A variant is available using a helical
instead of a whip for the lower element, giving similar performance
with reduced overall length. This antenna is suitable for mounting
on walls etc. but for best results should be kept well clear of surrounding
conductive objects and structures (ideally >1m separation).
|
| 2. |
The end-fed half wave is the
same length as the dipole but consists of a single rod or whip fed
at the bottom via a matching network. Mounting options are similar
to those for the quarter-wave whip. A ground plane is sometimes used
but is not essential. The end-fed arrangement is often preferred over
the centre-fed dipole because it is easier to mount in the clear and
above surrounding obstructions. |
|
|
| Yagi.
This antenna consists of two or more elements mounted parallel to each other
on a central boom. It is directional and exhibits gain but tends to be large
and unwieldy – for these reasons the yagi is the ideal choice for links
over fixed paths where maximum range is desired. |
| |
| Please note:
Using a yagi or other gain antenna with the TX1 will exceed the maximum
radiated power permitted by UK type approval regulations. It can be used
in the UK only in conjunction with the RX1 receiver. |
| |
| For best range in UK fixed link applications
use a half-wave antenna on transmit and a half-wave or yagi on receive,
both mounted as high as possible and clear of obstructions. |
| |
|
|
|
| |
Module mounting considerations
The modules may be mounted vertically or bent horizontal
to the motherboard. Note that the four components mounted on the underside
of the RX1 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. If the connection between module and antenna is more than about
20mm long use 50W microstrip line or coax or a combination of both. It is
desirable (but not essential) to fill all unused PCB area around the module
with ground plane.
|
|
Variants and ordering information
The TX1 transmitter and RX1 receiver are manufactured
in the following variants as standard:
| For alarm applications on 173.225MHz: |
| TX1-173.225 |
Transmitter |
| RX1-173.225 |
Receiver |
| For alarm applications on 173.250MHz:
|
| TX1-173.250 |
Transmitter |
| RX1-173.250 |
Receiver |
Other variants can be supplied to individual customer
requirements at frequencies from 151.300MHz to 173.250MHz and/or opitomized
for specific data speeds and formats. However these are subject to minimum
order quantity (MOQ) and long lead time. Please consult the Sales Department
for further information.
|
|
| |
Some of the non-standard
frequencies readily availble. i.e. no MOQ or long lead time, are as follows:
Part number:
TX1-xxx.xxx-10 and RX1-xxx.xxx-10 (where xxx.xxx is the operating frequency)
|
| Frequency (MHz) |
Type approval |
Notes |
| 121.500 |
- |
1, 2, 3 |
| 138.125 |
- |
1, 2, 3 |
| 149.170 |
- |
1, 2, 3 |
| 151.275 |
- |
1, 2, 3 |
| 151.300 |
Yes |
2, 3 |
| 151.775 |
Yes |
2, 3 |
| 152.175 |
Yes |
2, 3 |
| 152.500 |
Yes |
2, 3 |
| 152.575 |
Yes |
2, 3 |
| 152.650 |
Yes |
2, 3 |
| 152.850 |
Yes |
2, 3 |
| 153.8125 |
Yes |
2, 3 |
| 153.9125 |
Yes |
2, 3 |
| 153.925 |
Yes |
2, 3 |
| 154.463 |
Yes |
2, 3 |
| 155.475 |
Yes |
2, 3 |
| 155.715 |
Yes |
2, 3 |
| 155.725 |
Yes |
2, 3 |
| 156.525 |
Yes |
2, 3 |
| 157.420 |
Yes |
2, 3 |
| 159.685 |
Yes |
2, 3 |
| 159.6875 |
Yes |
2, 3 |
| 161.975 |
Yes |
2, 3 |
| 162.025 |
Yes |
2, 3 |
| 162.975 |
Yes |
2, 3 |
| 163.000 |
Yes |
2, 3 |
| 164.525 |
Yes |
2, 3 |
| 167.420 |
Yes |
2, 3 |
| 169.435 |
Yes |
2, 3 |
| 169.41875 |
Yes |
2, 3 |
| 172.420 |
Yes |
2, 3 |
| 173.075 |
Yes |
2, 3 |
| 173.175 |
Yes |
2, 3 |
| 173.200 |
Yes |
2, 3 |
| 173.960 |
- |
1, 2, 3 |
| 180.175 |
- |
1,2, 3 |
|
|
|
|
|
Notes: 1.
|
Complies with the ETSI standards but
NOT approved approved |
|
2.
|
For specialised application, NOT for
general purpose |
|
|
e.g: 121.500MHz is an international
distress frequency |
|
3.
|
NOT an European Harmonised frequency.
Consult local radio requlatory authority. |
|
|
| |
|
Type approval
The TX1/RX1 modules are type approved to European harmonised standard
ETSI EN 300 220-3 for UK use within the following categories:
|
| a. |
General applications in the band 173.2-173.35MHz
but excluding 173.225MHz. |
| b. |
Industrial/commercial applications
at the same frequencies as category |
| c. |
Fixed/in-building alarm applications
at 173.225MHz. |
| d. |
Medical/biological applications
(including airborne use for the tracking of birds) in the band 173.7-174.0MHz.
|
|
| |
| REQUIREMENTS FOR CONFORMANCE TO ETSI EN
300 220-3: |
| 1. |
Transmitted ERP (effective
radiated power) must not exceed the limit of 1mW (0dBm) for category
(a) or 10mW (+10dBm) for categories (b), (c) and (d). Equipment in
category (a) must include a 10dB attenuator between the TX1 RF output
pin and the antenna or feed, as specified on page 7 of this leaflet.
|
| 2. |
Any type of antenna system may
be employed provided that the applicable ERP limit is not exceeded
- i.e. transmitting antenna structures which exhibit ERP gain (such
as yagis) are not permitted. See pages 10-13 of this leaflet for details
of suitable antennas.
|
| 3. |
The module must not
be modified or used outside its specification limits. |
| 4. |
The module may only
be used to transmit digital or digitized data. Speech and/or music
are not permitted. |
|
| |
| OEMs incorporating the
TX1 as a component part of their product are authorized by Radiometrix Ltd
to quote our type approval provided that all the above conditions are complied
with. Breaching any of these conditions will invalidate type approval. |
|
|
| |
|
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:
Licensing policy manual
|
|
