RF427 905 MHz + 920 MHz Spread-Spectrum Radio

Overview

The RF427 is a high-speed 900 MHz serial radio designed for unlicensed operation in Brazil. The RF427 is a frequency-hopping spread-spectrum radio with a configurable transmit-power output of 5 to 250 mW and user-selectable channel masking for improved RF interference immunity. This power-sipping, yet speedy, radio provides a cost-effective way to network data loggers.

The RF427 is part of the RF407 series of radios that includes:

  • RF407: North America (FCC & IC), 902 to 928 MHz
  • RF412: Australia (ACMA RCM), 915 to 928 MHz
  • RF422: Most of Europe and some of Asia (ETSI), 863 to 873 MHz
  • RF427: Brazil (ANATEL), 905/920 MHz

Benefits and Features

  • Does not require individual operational license in Brazil
  • High-speed serial communication, optimized for PakBus networks
  • Low power (< 2 mA idle) during periods of inactivity
  • Supports point-to-point with RF retries and point-to-multipoint operations
  • Remote diagnostics using PakBus node operations

Images

Glam view
Glam view
Glam view
Front view
Back view
Left view
Right view
Top view
Bottom view

Specifications

Radio Type Frequency Hopping Spread Spectrum (FHSS)
Frequency 905/920 MHz
Country Used In Brazil
Transmission Distance
  • -Note- Transmission distance assumes line-of-sight and appropriate antenna. Line-of-sight obstructions, RF interference, and antenna type will affect transmission distance.
  • Up to 1.61 km (1 mi) with omnidirectional antenna; up to 16.09 km (10 mi) with higher-gain directional antennas at ideal conditions
Power Output 5 to 250 mW (user-selectable)
Receiver Sensitivity -101 dBm
Channel Capacity Eight 25-channel hop sequences sharing 43 available channels
Data Rate 200 kbps
Link Throughput 105 kbps (maximum)
Antenna Connector Reverse Polarity SMA (RPSMA) jack
LEDs Red TX/PWR and green RX
RS-232 Baud Rate 1200 to 115200 bps
CS I/O Modes SDC 7, 8, 10, 11, and ME master
Operating Temperature Range -40° to +70°C
Power 9 to 16 Vdc
Power Connector 2.5 mm DC power jack
Powered Over CS I/O or barrel plug
Maximum Nodes in Network 50
Current Required
  • Average Transmit: < 80 mA (250 mW TX Power)
  • Receive: 15 mA
  • Sleep: 0.5 mA (depending on power-saving mode)
Communication Ports
  • RS-232 9-pin D female
  • CS I/O 9-pin D male
  • USB Type B jack
Dimensions 11.1 x 6.9 x 2.7 cm (4.4 x 2.7 x 1.1 in.)
Dimension are from the tip of the antenna connector to the other side of the case, and from the bottom of the case to the top of the DB9 connector jack screw. The width includes the thickness of the screw heads on the screws that hold the case together.
Weight
  • 136 g (4.8 oz) without "Ships With" items
  • 283.5 g (10 oz) with "Ships With" items

Certifications

Brazil (ANATEL) 08335-17-10644 (standards in Resolution No. 506)

Compatibility

Communications

The RF427 is over-the-air compatible with other RF427-based products. The RF427 can only communicate wirelessly with other RF427 radios and other Campbell Scientific products that have the "-RF427" option.

Data Logger Considerations

Data Logger RS-232 CS I/O
CR200(X)
CR800/CR850
CR1000
CR3000
CR5000
CR9000(X)
CR300 *
CR6
CR510-PB
CR10X-PB
CR23X-PB
Mixed-array data loggers **

Notes:
*Use a 18663 null modem cable.
**It is possible to connect a mixed-array data logger (e.g., CR10, CR10X, CR23X, 21X, CR7) by using an SC932A or SC105 between the data logger's CS I/O port and the RF427's RS-232 port.

Frequently Asked Questions

Number of FAQs related to RF427: 1

  1. If you have an RF401/RF401A/RF407/RF411A/RF412/RF427 network that has been working reliably for months and then suddenly fails with intermittent data collection, the site hasn’t changed, and there hasn’t been any new construction in the area, the issue may be caused by a piece of new equipment that was installed on the job site during the COVID-19 pandemic.

    Because of the COVID-19 pandemic, some job sites implemented badge sensor technology for contact tracing and social distancing. Often, these devices operate on Wi-Fi or Bluetooth, but some of them operate in the 900 MHz range, which is used by our spread-spectrum radios and can, therefore, cause interference. Fortunately, you can resolve this issue using radio channel masking.

    The following outlines the steps that were taken to correct this issue in one specific example:

    1. The datasheet for the COVID-19 badge equipment was found and reviewed to determine that it was operating from 915 to 926 MHz.
    2. The manual for the RF407 900 MHz Spread-Spectrum Radio was reviewed. The manual reported the frequency for bit 0 and bit 63 as 902.4 MHz and 927.6 MHz with a channel spacing of 400 KHz.
    3. Using a mathematical calculation, it was determined that masking channels 31 to 60 would block off 914.8 MHz up to 926.4 MHz.
    4. Entering 0000000000000000000000000000001111111111111111111111111111110000 into a binary-to-hex converter provided a mask of FFFFFFFC0000000F. (The default Calculator app provided by Windows has a Programmer option listed under the hamburger menu that you can use for the conversion.)

      The Programmer option listed on the calculator


      The selected Programmer option on the calculator

    5. The mask of FFFFFFFC0000000F was used in the Radio Channel Mask setting, and the radio network returned to providing reliable operation.

    For more detailed information about using radio channel masking, refer to your spread-spectrum radio manual. For example, the RF407-Series manual has a section devoted to this topic.