Digitrax Radio Panels

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Summary: Digitrax makes a number of Radio Panels for use with wireless throttles.

Radio Panels

UR91 Radio Equipped/IR Receiver Unit

(Discontinued)

Adds simplex radio operation. Operates in the 900 MHz band, can support up to 10 radio/IR throttles. Supports simplex radio and IR simultaneously.

Usually only one is needed for radio operation. Simplex throttles must be connected to the panel by their cable to program, select or dispatching a locomotive.

UR92 Duplex Radio Transceiver/IR Receiver

The UR92/UR92CE was retired in February 2021

Duplex radio throttles do not need to be tethered to select or dispatch a locomotive. Supports up to 20 duplex throttles. Most installations will only require one UR92. Also supports the IR throttles.

Duplex radio operates in the 2.4 GHz band, simplex is not supported. Includes Group Mode, to minimize interference at shows when several Digitrax Duplex systems are in use.

UR92CE Duplex Radio Tranceiver/IR Receiver for Europe

Version for the EU.

UR93 Radio Panel

This device was only available with the new Evolution Express starter set. As of August 2020 it became a standalone product.

LocoNet Duplex Transceiver

  • This unit does not support IR throttles
  • Better range than the UR92, claimed to be more than double
  • Compatible with existing UR92 duplex radio systems
  • Improved multi-path rejection
  • Status LEDs

Throttle Support

The following Duplex Radio throttles are supported.

  • DT602D/DE
  • DT500D
  • DT402D UT4D
  • Combinations of the above throttles are supported
IR modes are not supported.

The UR93 transceiver supports up to twenty Digitrax Duplex throttles simultaneously. Adding a UR93 to an existing UR 92 duplex radio equipped layout will offer improvements, such as a 15dB increase in signal strength. All duplex throttles will attempt to connect to the UR93's stronger signal for better operation. As the UR93 is not limited by the number of connections it can handle much more traffic than a wireless router or other device.

Compatibility

Available UR93E for EN-300-328 Wireless conformity.

RF28 Transceiver Module

The UR93 has a new Digitrax designed and manufactured RF28 Modular 2.4GHz Transceiver. The RF28 is configured to interoperate with existing UR92 LocoNet access points and DT500D and UT4D duplex throttles worldwide. All Duplex units employ IEEE 802.15.4 compatible devices using 2.4GHz Direct Sequence Spread Spectrum (DSSS) modulation.

The module is smaller than the older transceiver modules. This allowed it to fit the new UT6D Wireless Throttle introduced in November 2020.

RF28 Features
  • Estimated 30dB gain in power. This would be the equivalent of a 1000–fold increase in effective power.
    • This helps overcome directivity, multipath and signal attenuation issues. While +6dB is four times the power, the short wavelength means multipath distortion and movement of the antenna can reduce range significantly.
    • The human body (salt water column) can attenuate an RF signal by 20dB.
  • Diversity Antenna Design: A pair of high efficiency antennas using orthogonal polarizations maximize reception and transmission power. The antenna in use is visually indicated on the DT602D and UT6D by the colour of the channel number on the LCD, in Green or Blue.
  • The RF28 module is certified for close to maximum transmit power for the ~2.2MHz bandwidth needed at a 250 kb/s data rate. (FCC)
    • CE Certified units are approximately –8dB lower as per regulatory requirements.
  • The 250 kb/s data rate is ideal for a handheld device, and is more efficient than WiFi (802.11) data rates.
  • WiFi systems may have up to 20MHz of bandwidth/channel spacing. To maintain acceptable error rates, increasing the receiver's bandwidth for a faster bit rate reduces sensitivity, requiring more power from the transmitter.
  • WiFi may be more challenging for users to set up compared to the Digitrax wireless throttles and access points.
  • IEEE 802.15.4 has a 32 bit DSSS modulation scheme which results in significant gains against co-channel RF interference.
  • The older simplex links at 916.5MHz using narrow band FM modulation at 12kBps provided excellent range at low power, and interference rejection and suppression via FM Capture.
  • European regulations require additional capability to reject interference. The result is a device which can operate reliably in a mixed RF environment, providing other devices do not limit channel availability or block other devices. The UR93 incorporates an enhanced duplex beacon capture and tracking logic.
  • The DT602D and UT6D throttles will work with an existing UR92 infrastructure, while providing the benefits of a +15dB link gain. Range and fade resistance are also improved. The throttles can also automatically track and use more UR92s in a large layout setting.
  • The addition of a UR93 to an existing UR92 infratsture will also provide benefits, such as the gain in link power for all duplex throttles. All duplex throttles will track the high power signal from the UR93 automatically.
  • Better Performance: The UR93 is not limited in capacity like a router or other network device, allowing it to handle any level of communications traffic with ease.

Manufacturer Website