Category: Tech Notes

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How to Protect Outdoor Radio Installations from Lightning and Weather

An outdoor radio link depends on more than the radio itself. Exposed antennas, cables, and connectors also need protection from weather and electrical surges.

Antennas and their connections are exposed to rain, snow, ice, and lightning. Moisture can corrode connectors, while lightning-induced surges can travel along the RF cable and damage the radio and connected equipment.

Two accessories can reduce these risks: a properly grounded lightning protector that provides a path for surge current, and weatherproofing that helps keep moisture and contaminants out of cable connections. Neither guarantees protection against a direct lightning strike.

Why Use a Lightning Protector?

Antennas are typically installed at elevated locations, which can leave the antenna system exposed to lightning-related electrical surges.

The YASP1G-NFF Impulse Lightning Protector is installed in the RF feed line between the antenna and the radio. SATEL recommends installing a lightning protector in the feed line when a station is installed in a location exposed to lightning.

A typical installation looks like this:

The lightning protector must be bonded to an appropriate grounding system according to its installation instructions and applicable electrical requirements. Its effectiveness depends on the entire grounding and bonding arrangement.

Why Weatherproof Outdoor Connections?

Outdoor antenna system connections can allow moisture, condensation, dust, and other contaminants into the connection if they are not properly sealed.

The SAWPM Mini Weatherproofing Kit is designed for exposed RF and cable terminations. It uses sealing materials around the connection to help keep moisture and contaminants out and maintain reliable system performance.

How Do You Weatherproof an Outdoor RF Connection?

Always follow the installation instructions provided with the weatherproofing kit and connected equipment.

1. Tighten the connection

Make sure the RF connector is properly secured before applying weatherproofing.

2. Clean and dry the connection

Remove moisture, dirt, and anything else that could become trapped beneath the seal. Trapped moisture can accelerate corrosion, so apply weatherproofing only when the connection is dry.

3. Apply the first layer of plastic tape

Wrap the connection with overlapping plastic tape, keeping the surface smooth and free of gaps.

4. Apply the rubber sealing tape

Wrap the rubber sealing tape tightly around the entire connection, overlapping each layer as you go. Press and mold it firmly into place, sealing every gap and opening to keep moisture out.

5. Finish with plastic tape

Cover the rubber sealing layer with overlapping plastic tape to secure and protect the completed seal.

Protect Every Exposed Connection

If a lightning protector is mounted outdoors, remember that there is an RF connection on both sides of the protector.

Antenna cable → Lightning protector → Jumper cable

Any connection exposed to weather should be evaluated and weatherproofed as needed.

Protecting these connections during installation can help reduce moisture-related failures and unnecessary service calls.

Recommended Products

YASP1G-NFF

Impulse lightning protector with N-female connectors for reducing surge energy reaching connected equipment when properly installed and grounded.

SAWPM

Mini weatherproofing kit for sealing exposed RF and cable connections against moisture, dust, and condensation.

Need help selecting accessories for an outdoor radio installation? 

Contact Satel USA.

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Tech Note: Choosing the Right Antenna Cable for Your RTK Radio

When setting up an RTK radio antenna system, choosing the right cable is important to ensure reliable performance. This guide gives you practical recommendations on cable types and run lengths.

Cable Types

For RTK antenna runs, we focus on two primary options: LMR 240 and LMR 400.

The LMR naming convention is based on the cable’s outside diameter in inches: LMR 400 is approximately 0.400 inches in diameter, LMR 240 is 0.240 inches in diameter.

LMR 400 has lower signal loss and a thicker, stiffer jacket. It’s more durable and best for long cable runs.

LMR 240 is thinner, lighter, and easier to work with. Loss is slightly higher but negligible on shorter runs. For most installs under 50 feet, it’s the more practical choice.

Both cable types also come in an “UltraFlex” variant that uses a stranded conductor instead of a solid one. Its slightly higher loss but easier to work with. UltraFlex cables are good choices for mobile/temporary setups where cables may be frequently handled. Solid core (standard LMR) cables are better for permanent installations and longer cable runs.

LMR 240

LMR 400

(UltraFlex variations have the same measurements but use stranded conductors)

Cable Length Recommendations

We recommend keeping cable losses under 6dB as a rule of thumb, with under 3dB being even better. These aren’t hard limits – a system with higher loss may also work well, especially if it is shorter range.


This means:

  • Under 50 ft: LMR 240 is the practical choice. Use UltraFlex for frequently handled cables.
  • 50 to 100 ft: Either works, but prefer LMR400 for 900MHz or long range links.
  • 100 to 150 ft: Use LMR400 to minimize cable loss. You may also consider a higher gain antenna for systems with long cable runs.
  • 150+ feet: You may want a thicker cable (LMR600 or better), especially for 900MHz. At some point, a radio repeater may be more practical than a very long cable run.

For installs with tight bends, reach out before you buy. Multi-section runs are sometimes necessary.

Signal Loss Reference

Loss at 460 MHz / 100 ftLoss at 915 Mhz / 100 ft
LMR240 UltraFlex6.4 dB9.2 dB
LMR2405.4 dB7.7 dB
LMR400 UltraFlex3.3 dB4.7 dB
LMR 4002,8 dB4.0 dB

Have a unique install scenario? Contact Satel USA today.

Coming soon: Lightning Arrestors & Weatherproofing | Antenna Cable Installation Tips

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Tech Note: Understanding LED Indicator Lights on Your Satel Radio

Applies to: All Satel radio modems with TD/RD LED indicators

What Normal Operation Looks Like

Depending on how your radio is configured in the system, here’s what you should see:

RoleExpected LED Behavior
BaseTD blinks red once per second
RoverRD blinks red once per second
RepeaterTD and RD both blink red in sequence, once per second

If your lights match the above for your radio’s role, your system is operating normally.

The Only Two Lights That Matter for RTK

Your Satel radio has five LED indicators on the front panel, but for RTK operation, only two of them tell you anything useful:

TD: blinks red, your radio is transmitting 

RD: blinks red, your radio is receiving

Everything else is not relevant to RTK diagnostics. 

What Abnormal Operation Looks Like

No TD on Base 

The base is not sending corrections out through the correct port. Check that your serial port output is configured correctly.

No RD on Rover 

This points to one of two things:

  • Configuration issue — the rover is not programmed correctly and will never receive data until settings are fixed
  • Range issue — the radio is configured correctly but is too far from the base or repeater to maintain a reliable link

What About the Other Lights?

TD light is green (Base) 

This means Test Tx mode is active. This is not normal operation. Disable test mode before deploying the radio in the field.

CD light 

The CD light reflects radio interface activity, it can blink red (transmitter on), orange (noise), or green (reception). However, it is not a reliable diagnostic tool. The orange and red colors are difficult to distinguish, and the light can show reception even when no usable data is coming through the serial port. For troubleshooting purposes, ignore the CD light and focus on TD and RD.

RTS and CTS lights 

These indicate serial line status but are not used in RTK applications. They may blink, but they don’t tell you anything meaningful about your radio’s performance.

Seeing Unexpected Behavior?

If your lights don’t match what’s described above, start here:

  1. Confirm the radio’s role (Base, Rover, or Repeater) and check the expected LED behavior in the table above
  2. Verify that TD is blinking on the base; if not, check serial port output settings
  3. Verify that RD is blinking on the rover; if not, check configuration settings and radio range
  4. If you’re running a repeater, confirm that both TD and RD are blinking in sequence

If you’re still not getting the expected behavior after checking the above, contact Satel USA support for assistance.

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FCC Part 90 License: 5 Essential Things You Need to Know

If you’re running a Satel 400MHz radio, you need an FCC Part 90 license before you transmit. Here’s what you need to know:

1. Satel 400 MHz radios operate in a licensed band.

So, you need a Part 90 license under the FCC’s Private Land Mobile Radio Service. It’s available to businesses, individuals, government entities, and many other groups as defined under 47 CFR § 90.35 and 47 CFR § 90.20. The license type and frequency pool depend on your use case, not just your entity type.

2. All operation requires a license.

Some operators assume low-power transmissions or specific frequencies don’t require a license. They do. If you’re operating a Satel 400 MHz radio, FCC Part 90 applies regardless of how you are using it.

3. Licensing exists because spectrum is a shared resource.

Licensing ensures access to critical long-range frequency bands is controlled so businesses, public safety agencies and more can access the wireless communications they depend on.

4. Itinerant frequencies are shared.

Itinerant frequencies are a small group of shared frequencies that can be used for wide area operation (such as statewide or nationwide). A license is still required to use them, even though they are not exclusive. Unlike coordinated, fixed location licenses, operation on itinerant frequencies may be subject to unintentional interference from other licensed users. It is recommended to have multiple itinerant frequencies available if operating on those channels.

5. Your radio has to be certified, not just your operation.

FCC Part 90 rules apply to the hardware, not just the operator. Under 47 CFR § 90.203, every transmitter marketed or operated under Part 90 must be of a type that has been certified for use under that part. Part 90 certification gives you the ability to operate, but only under the rules specified in Part 90, which requires operators to be licensed.

If you need help getting licensed, SATEL USA offers a straightforward licensing service for high-power base radios.

Get started with FCC licensing →

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Tech Note: Why Is My Range Shorter Than Expected?

The Problem

You’re getting great range one day—5 or 6 miles—and the next day you’re only getting a mile. What changed? This is one of the most common questions we hear and the answer may not be what you expect.

The Short Answer

For practical RTK distances, signal loss is about obstructions between your transmitter and receiver—not distance itself.

Your Satel 35W radio has enough power to get to the moon or even farther. But it can’t go through a mile of solid terrain, even though the moon is significantly farther away. That’s the fundamental principle of radio range for typical Satel radio use cases: obstructions matter, distance alone does not.

Why Range Varies Between Locations

Not all locations are created equal. Just because you got 5 miles with your exact same setup at one job site doesn’t mean you’ll get 5 miles at another. Here’s why:

  • Terrain changes – Hills, valleys, and elevation differences
  • Built environment – Earth, metal, and concrete are very effective at absorbing radio waves. Wood and glass will also reduce signals to a lesser degree
  • Natural environment – Trees and other vegetation reduce signal levels
  • Your position on the job site – Working locations on a job site can be drastically different throughout the day

The key insight: You can receive a signal at -70 dBm at 5 miles in one location, and receive the same -70 dBm signal at only 1 mile in another location. The signal strength is the same despite one link being much farther because the obstructions are different.

Basic Troubleshooting Checklist

Before assuming you have a hardware problem, check these basics:

1. Antenna Connections

  • Are all antennas screwed in tight?
  • Are connectors clean, dry, and free of corrosion?
  • Check both base and rover antennas

2. Cable Inspection

  • Look for cracked jackets on antenna cables
  • Check for exposed wiring or visible damage
  • Damaged cables are uncommon but simple to spot

3. Antenna Orientation

  • Antennas need to be oriented the same direction (vertical is most common)
  • Not crooked, tilted, or sideways

4. Antenna Height

  • Is your transmitting antenna as high as possible?
  • There’s potentially a huge difference in range transmitting at 5 feet above ground level vs 10 feet or more
  • Antenna tripods are available for temporary installs that need more height

The #1 Solution: Antenna Height

Getting your transmitting antenna higher is the best way to increase range.

Why Height Matters

Higher antennas can “see over” obstructions that would completely block antennas at a lower height. Even a 10-foot increase can sometimes make the difference between no signal and full RTK lock.

Practical Height Solutions

  • Use a tripod with an extension pole – Our K-YKIT-AK (Radio Antenna Tripod) gets you up to 13 feet (4 m) total elevation
    • Tripod extends to 5.5 ft (1.7 m)
    • Telescoping mast reaches 7.5 ft (2.3 m)
    • Combined height: 13 feet (4 m)
  • Mount on top of structures – Construction offices, vehicles, existing buildings
  • Avoid ground-level setups – Shoulder height (~5 feet) is often insufficient for long distances

Example Scenario:

Problem: Base antenna at shoulder height (5 feet) next to the construction office, trying to reach equipment on the other side of the building.

Diagram showing radio signal blocked by building obstruction

Solution: Mount the radio antenna on top of the construction office. This:

  • Eliminates the building obstruction
  • Adds significant height
  • Extends range in the previously blocked direction

Counter-Example: Building a road through a forest with tall trees. Moving your antenna from 5 feet to 10 feet makes no practical difference because the trees are still blocking the signal. In this case, you might need to use a repeater radio or another approach.

What About the Receiver Antenna?

While the transmitting (base) antenna is usually easier to raise, raising the receiving (rover) antenna helps an equal amount. If you can get your rover antenna higher—even by a few feet—it can improve your link strength.

Related Resources

Need help? 

Contact SATEL USA technical support for site-specific guidance and troubleshooting assistance.

Phone: (408) 973-1740
Email: support@satelusa.com

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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.

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Tech Note: High Power Radios and Heat

High power radios like the Satel EASy Pro and EASY Pro+ generate a lot of heat while transmitting, so they can get hot to the touch – especially when it is also hot outside. While output power on these radios is up to 35W, they need as much as 120W of power to generate this signal, with the difference ending up as heat (up to 85W of heat).

If radios are getting too hot, there are numerous ways to reduce or mitigate the amount of heat generated. Many of these techniques will also save power and increase run time on battery systems.

  • Avoid using slow GMSK radio protocols including TrimTalk450 and PacCrest-GMSK if possible. These modes can generate up to twice as much heat as more efficient 4FSK modes, like Satel 3AS or PacCrest-4FSK.
  • Reduce transmit power. Often 25W or even 10W of transmit power is plenty to get the range you require. Additional height on the transmitting antenna system, such as using a tripod or antenna mast system is often more useful than high transmitter power to increase range.
  • Use Satel 3AS mode with no error correction (also known as forward error correction or FEC). Error correction adds significant overhead (approximately 30%) which runs the transmitter longer and is only useful in conditions with extremely poor signals. While disabling error correction can reduce range, this is usually not meaningful for 35W transmitters.
  • Make sure the TD light is not solid green. This indicates the radio is in test mode and this will cause excess heat generated and may disrupt the normal operation of the radio system. A blinking green TD light is expected in normal operation and indicates periodic data transmission.
  • Ensure the radio is mounted vertically (antenna connector facing up), so that air can flow up through the heat sink.
  • Get a 25kHz license. 25 kHz channels are up to twice as fast as 12.5kHz channels, so operating at 25kHz will run the transmitter for shorter periods of time and generate less heat. Note: Operating at 25kHz in the United States requires a license specifically authorizing this use and requires the use of 4FSK or faster compatibility modes.
  • If using an EASy Pro radio, consider upgrading to a EASy Pro+. The EASy Pro+ has a wider range over power outputs (1-35W vs EASy Pro’s 10-35W), and is 20-50% more power efficient, which leads to less heat generated.

Still have questions? Contact us for additional support.

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Tech Note: Adding a Channel List to the SATELLINE-4Pro

Because the SATELLINE-4Pro is only available with “Survey Mode” firmware, Configuration Manager software is essential for loading a channel list and changing most settings. The most recent version of the software can be downloaded from our Support page.

Following are step-by-step instructions on loading a channel list to your 4Pro radio:

  • Connect the 4Pro to power (check that you have the right voltage).
  • Open SATEL Configuration Manager & click the “Program Preferences” tab.
  • Confirm that the correct COM-port is selected and that the baud rate matches that of the radio (default baud rate of the 4Pro is 115200 bps). (Important: to be able to change settings, in the “Program Preferences” tab, under User Level Settings enter the maintenance password and login.)
  • Select the blue “Connect” tab to fully access the modem settings.
  • Select “Modem Settings” tab
  • Select “Channel Selector”, blue button at the top right.
  • If creating a new channel list, in the Channel Selector Window, select “Add” and the Channel Editor Form will appear. Here you can set the User Channel (1-XX), Tx and Rx Frequencies, Bandwidth (12.5, 20 or 25 kHz), and Channel Tx Power (NOTE: if Tx Power is left blank, the radio will default to the max. power of that unit and the saved channel list can be reloaded to any SATEL radio. See previous blog post here for more information.). Input your selection for the user channel and press OK. Continue this process for each subsequent channel, to complete your channel list. (If loading an existing channel list, in the Channel Selector Window, select “Load”, where you will then be able to browse for your saved CFG or CSF file)
  • It is recommended that you then click the “Save” button, to save your new channel list to your PC.
  •  When done, click “Close”. Change “Channel List In Use” to “ON”. The edited settings will show in red font. 
  •  Select the blue “Write Settings” button. Once complete, these settings will change to black font, indicating they’re loaded to the radio.
  •  We recommend you select “Save Configuration to File” to save all specified settings to your PC, before selecting “Disconnect”.

For additional questions, or if you’d like to suggest a technical topic for us to review in our blog, please email support@satelusa.com.

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Troubleshooting SATEL Radios

The most frequent cause of Satel Radio issues is a mismatch in settings between the transmitting radio and the receiving radio. The key settings that must be the same on both radios are:

  • Frequency
  • Channel Spacing
  • Radio Compatibility/Protocol
  • Error Correction (FEC)

Note: On other Satel-compatible radios, or via 3rd party interfaces (such as Leica or Carlson Software), these terms may have different names. Other settings, such as Error Checking are uncommonly used.

Troubleshooting Steps

Base Radio

  1. Start with the base/transmitting radio. The “TD” light should be blinking. If it isn’t, that means the transmitting radio is not receiving data via its serial port. Check the settings on the attached device to ensure it is correctly sending data via the serial link.
  2. Note down the 4 above settings using the radio screen and buttons. The settings are found in the following menus:
    1. Frequency: “Radio frequency” menu (“TX & RX freq”)
    2. Channel Spacing: “Radio frequency” menu (“Ch Spacing”)
    3. Radio Compatibility: “Radio settings” menu (“Compatibility”)
    4. Error Correction/FEC: “Additional” menu (“Error corr.”)

Remote Radios

  1. Start by checking received signal strength. In the upper right corner, the number shown with a negative sign is the RSSI. A normal RSSI should be between -40 and -100 or so, with a higher number closer to the transmitting radio, and a lower number farther away. During normal operation the RSSI will likely change between a higher number, such as -60 and a low number (typically -120 or below).
    1. If the number stays low (below -100), the radio is not receiving a signal over the air, which indicates the frequency on the base radio and remote radio is not matching, or the base radio is not transmitting. Check and program the frequency on both radios.
  2. If the signal strength is high (above -100), or changing between a high and low signal, the next step is to check the RD light, which should be blinking. If it isn’t, this indicates a settings mismatch (the radio hears a signal, but can’t decode it). Check and program the 3 other settings (Channel Spacing, Radio Compatibility, Error Correction/FEC).
  3. If the RD light is blinking, but your data still isn’t making it through, check the Baud Rate on the receiving radio (in the “Port 1” menu), and ensure it matches the settings on the device attached to the receiving radio.

Further Troubleshooting

The above steps cover the most common issues seen when setting up a Satel radio system. If the instructions don’t address your situation, or you are unsure how to match settings on a Satel-compatible device, such as a radio from another manufacturer, or via 3rd party configuration software, please contact us.