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Tech Note: SATEL Radio Setup Checks for RTK Base and Rover Links

Purpose

Use this note to troubleshoot common setup issues when a SATEL base radio and rover radio do not pass GNSS correction data.

1) Why do my base and rover radios not communicate (even on the same frequency)?

Most common cause

Mismatched radio settings block the link even when both radios show the same frequency.

Quick checklist (match base and rover)

  • Frequency (MHz)
  • Channel spacing (kHz)
  • FEC / Error Correction (ON or OFF)
  • Radio Protocol / Compatibility (must match)
  • Serial port settings (not needed for repeaters)
    • Baud rate (serial speed)
    • Parity
    • Data bits and stop bits (if used in your setup)

Recommended troubleshooting steps

  1. Confirm both radios use the exact same frequency and channel spacing.
  2. Confirm both radios use the same protocol.
  3. Confirm both radios set FEC the same way (both ON or both OFF).
  4. If the radio connects to a GNSS receiver via serial:
    • Match the radio serial settings to the GNSS receiver serial settings.
    • Verify the GNSS receiver outputs corrections on the same port wired to the radio.

2) What Baud Rate, Parity, and Protocol Should I Use Between SATEL and GNSS?

Rule

The baud rate must match on both ends. If the receiver talks at 38400, the radio port must also use 38400.

Common baud rate examples (receiver dependent)

  • Trimble: 38400
  • Topcon: 38400
  • Carlson: 9600 or 115200
  • Leica: 19200 or 115200

Notes

  • Parity and framing vary by receiver and port profile.
  • Use the GNSS receiver port settings as the source of truth, then mirror them in the SATEL radio.

3) How Do I Confirm My SATEL Radio Is Receiving Correction Data From the GNSS Base?

Primary field check

  • The RD (Receive Data) indicator blinks when the radio receives serial data into the radio.

What it tells you

  • If RD blinks, the base GNSS receiver is likely sending correction data into the radio.
  • If RD does not blink, check:
    • Cable and pinout
    • Port selection on the GNSS receiver
    • Serial settings match (baud, parity, etc.)
    • GNSS base is actually outputting corrections (RTCM, CMR, CMR+)

4) How Do I Configure SATEL Radios for RTCM vs CMR or CMR+?

Key point

SATEL radios transmit data transparently. The radio does not interpret, convert, or modify RTK correction formats.

What you actually configure

  • Set the GNSS base to output the correction format you need (RTCM, CMR, or CMR+).
  • Make sure the rover GNSS is configured to accept that same format.
  • Keep the radio link settings aligned (frequency, spacing, protocol, FEC).

Practical takeaway

If the rover cannot use RTCM (or cannot use CMR/CMR+), fix it in the GNSS configuration, not in the SATEL radio.

Fast Diagnostic Flow (On-Site)

  1. Match radio link settings: frequency, channel spacing, protocol, FEC.
  2. Confirm RD blinks on the base radio.
  3. Confirm rover GNSS accepts the base correction format.
  4. Verify serial port settings match between GNSS and radio.

If you’re still having problems, feel free to contact our support team.