• CE Certified by independent Notified Body
• Verified to comply with harmonised radio standard ETSI EN 300 220-3 and EMC standard ETSI EN 301 489-3 by accredited Test Laboratory
• PCB Mounting, space saving SIL style
  
• SAW controlled wide band FM transmission
  
• Data rate of up to 10kbps
  
• Analogue or Digital data input
  
• Wide supply range 2.7V-4.0 or 6.0V-9.0V @ <17m

The transmitter modules are most commonly employed in Wireless Security systems. The transmitter and the matching RX2-433-14 receiver are approved to harmonised radio standard ETSI EN 300 220-3 and EMC standard ETSI EN 301 489-3. The TXM and RX2 modules will suit one-to-one and multi-node wireless links in applications including car and building security, EPOS and inventory tracking, remote industrial process monitoring and computer networking. Because of their small size and low power requirements, both modules are ideal for use in portable, battery-powered applications such as hand-held terminals.

Typical applications include :-

• Domestic and commercial security
• Guard patrol / lone worker protection
• Medical Alert / Nurse Call systems
• Mobile panic attack
• Computer networking
• Remote industrial process monitoring
• Data transfer through hazardous environments
• Lighting control, Garage door openers
• Fire alarms Picture / antique protection alarms
• Remote control, Access control

Brief description

The TXM-433 is designed to work with the matching receiver RX2-433-14 (or SILRX). With the addition of simple antenna the pair may be used to transfer serial data up to 200m. The range of the radio link is very variable and depends upon many factors, principally, the type of antenna employed and the operating environment. The 200m quoted range is a reliable operating distance over open ground using 1/4 whip antenna at both ends of the link at 1.5m above ground. Smaller antenna, interference or obstacles (e.g. building etc.) will reduce the reliable working range (down to 30m in extreme cases). Increased antenna , slow data or a larger receive antenna will increase the range (our best is 3km).

TXM`s - Block diagram.

Mechanical dimensions.

Absolute Maximum Ratings:

Notes

1. Module on 50mm square ground plane, helical antenna
2. Supply 6 to 9V, temp -10°C to + 55°C.
3. <-54 dBm in bands 41-68, 87.5-118, 162-230 & 470-862 MHz
   <-36 dBm else where below 1GHz , <-30dBm above 1GHz
4. Standard modulation: 2kHz square wave, 0 to Vcc
5. High or Low pulse.
   
   Figure 3: TXM-433-5 version test circuit

Notes

1. Supply 2 to 3.6 volt, temp -10 to + 55°C.
2. <-54 dBm in bands 41-68, 87.5-118, 162-230 & 470-862 MHz
   <-36 dBm else where below 1GHz , <-30dBm above 1GHz
3. Standard modulation: 2kHz square wave, 0 to Vcc
4. High or Low pulse.
   
   Figure 4: TXM-433-10 version test circuit
   
   Figure 5: Typical performance curves
   

The TXM-UHF transmitter requires only a data modulation input, supply, ground and an antenna.

Power supply requirements

The module will operate over the range 6 to 9V and is typically powered by either 9V 'PP3'. The module is not reverse polarity protected. Reverse supply voltages higher than 2V will cause damage and must therefor be externally protected against.

Modulation requirements

The TXM-UHF transmitter has a DC to 10kHz modulation bandwidth and will accept direct analogue (AFSK) or digital data. A modulation lowpass filter (10kHz @ -6dB, 1st order) is used internally. Although the modulation bandwidth of the transmitter extends down to DC as does the AF output of the receivers, it is not possible to pass data with a DC component due to frequency errors & drifts between the transmitter and receiver. Frequency differences between the transmitter and reciever will produce a DC offset error which causes the data slicer in the receiver module to give errors on long high or low pulses which exceed the maximum pulse width, see the receiver's data sheet for more detailed information. Data Input, pin 5, is normally driven directly by CMOS logic levels from a data encoder IC. There is a wide range of encoder/decoder IC's available which may be used with the modules:

Three types of integral antenna are recommended and approved for use with the module:

A) Helical:

(B) Loop,

C) Whip

Antenna Selection Chart

The duty cycle is defined as the ratio, expressed as a percentage, of the maximum transmitter "on" time on one or more carrier frequencies, relative to a one hour period. Where an acknowledgement message is required, the additional transmitter "on" time shall be included.

There is a 10% duty cycle restriction on 433.050-434.790 MHz band in most of the EU member states.

The TXM-433 is a RF module intended to be incorporated into a wide variety of applications and finished products, Radiometrix has no control over the end use of the TXM-433.The harmonised band 433.050 to 434.790 MHz as detailed in Annex 1 Band E of CEPT/ERC Recommendation 70-03 (which can be downloaded at http://www.ero.dk/scripts/docmanag98/dm.dll/QueryDoc?Cat=Recommendation)
has list of countries where Duty Cycle restriction apply.

Module users should, therefore, ensure that they comply with the stated Duty Cycle requirements of the version of CEPT/ERC Recommendation 70-03 in place at the time of incorporation of the TXM-433 into their product. It should be noted that the stated Duty Cycle must not be exceeded otherwise any approval granted for the TXM-433 will be invalidated.

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