Low Cost VHF Narrow Band Receiver

The CVR1 receiver modules offers a low cost, reliable data link in a Radiometrix BiM standard pin out and footprint. CVR1 is availble in 173.225MHz frequency as standard. CVR1 is compatible with the Radiometrix TX1 and BiM1T transmitters.

Figure 1: CVR1-173.225-10


  • Conforms to EN 300 220-3 and EN 301 489-3
  • Standard frequency 173.225MHz
  • Other frequencies from 120MHz to 180MHz
  • Data rates up to 10kbps for standard module
  • Feature-rich interface (RSSI, analogue and digital baseband)
  • Low current consumption
  • Low battery life

CVR1 is the cut down version of standard BiM1R receiver and lacks internal supply regulator and screening. Although CVR1 is made available for low end wireless applications where the cost is also a concern, its RF performance is not compromised.


  • Solar powered remote installation
  • Data loggers
  • Industrial telemetry and telecommand
  • In-building environmental monitoring and control
  • Security and fire alarms

Technical Summary

  • Size: 33 x 23 x 8mm
  • Operating frequency: 151.300MHz
  • Supply : 3V (regulated)
  • Current consumption: 7mA
  • Data bit rate: 10kbps max.
  • RSSI output with >60dBm range
  • 10kbps, -120dBm sensitivity (for 12 dB SINAD)

Evaluation Platform: Universal Evaluation kit or Narrow Band Evaluation Kit
Matching Transmitters: TX1 , TX1H , HX1, BiM1T or BiM1HT

User interface

Pin No.
Name Function
1 0V Ground
2 Vcc 3.0V regulated DC power supply
3 RX select Pull low to enable Receiver
4 NC No connection
5 NC No connection
6 AF 500mV pk-pk audio. DC coupled, approx 0.8V bias
7 RXD 2.5V pk-pk logic output of data slicer. Suitable for Biphase codes
8 RSSI DC level between 0.5V and 2V. 60dB dynamic range
9 0V Ground

1. /RX SELECT and RXD have internal (10k approx.) pull-up to Vcc
3. Pin out is as BiM1. On RF connector end only pins 1, 2, 3 are present.

Absolute maximum ratings

Exceeding the values given below may cause permanent damage to the module.

Operating temperature -10°C to +60°C
Storage temperature -30°C to +70°C
RF in (pin 1) ±50V @ <10MHz, +13dBm @ >10MHz
All other pins -0.3V to +16.0V
Interface: User: 9pin 0.1" pitch molex
RF: 3pin 0.1" pitch mo

Condensed specifications

(Vcc = 3V / temperature = 20°C unless stated)

RF centre frequency
173.225 (other VHF 120-180MHz by special order)
Frequency stability +/- 2.5kHz
Channel spacing
Number of channels
Supply Volatge
3V (+/- 10% )
7mA receive
Operating temperature -10°C to +60°C (Storage -30°C to +70°C)
Size 33mm x 23mm x 8mm
Spurious radiations Compliant with ETSI EN 300 220-3 and EN 301 489-3
9pin 0.1" pitch molex
3pin 0.1" pitch molex
RF sensitivity @ 12dB SINAD
RF sensitivity @ 1ppm BER
RSSI range
-85dB or better
Image rejection
-60dB or better
Adjacent channel rejection
Spurious response rejection
-60dB or better
LO re-radiation
Baseband bandwidth @ -3dB
AF level
DC offset on AF out
Outputs RSSI, Data, AF

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