ELT RTK Base

Quick Start

Important: all connections must be made while the base station is disconnected from power!

1. Mount the antenna on the roof and connect its cable to the base station’s IN connector (SMA type).
2. Only for ELT0×31: If you wish, you can mount the base station to a table, a wall, or a rack.
3. Connect to Internet. Variants:
   Ethernet with PoE (Only for ELT0×31)
   - Plug Ethernet into the port.
   Ethernet without PoE (Only for ELT0×31)
   - Plug Ethernet into the port.
   - Plug the power cable into the USB Type-C port on the right.
   - Plug the base station’s power adapter into an electrical outlet.
   WiFi
   - Plug the power cable into the USB Type-C port on the right.
   - Plug the base station’s power adapter into an electrical outlet.
   - Wait for the “Internet” LED to start blinking, then press the WPS button on your WiFi access point. Within 10–20 seconds, the blinking will stop and the “Internet” LED will light up solid.
4. Wait 2-3 minutes.
5. Open http://rtkbase.local/
6. On the web page that opens, enter the default password admin.
7. Verify that everything is working.

More details: Getting started

Connection options

First, determine how you will connect the base station. There are three options: via Ethernet (if available), via WiFi using WPS, or WiFi without WPS. If you are connecting via WiFi, check whether your access point has a WPS button.

WiFi without WPS

If you are connecting via WiFi without WPS, need a static IP address (and know what that is), want SSH access (and understand why), or don’t have DHCP (another rare case for experts), you’ll need to configure the system first. Instructions are in the section "Advanced Base Station Configuration”.

Hardware Setup

Mount the antenna on the roof and connect its cable to the base station’s IN connector (SMA type). If you are connecting via Ethernet, plug it into the port. Then insert the power cable, but do not plug it into the wall socket yet. Details can be found in the “Connection” section. On advanced (wired) stations, plug the power cable into the USB Type-C port on the right. On budget (wireless) stations, plug the power cable into the PWR IN connector.

Important: all connections must be made while the base station is disconnected from power! See the “Connection” section for more.

Mounting Options

If you wish, you can mount the base station to a table, a wall, or a rack, as described in the “Mounting” section.

WiFi WPS Setup

Plug the base station’s power adapter into an electrical outlet. If you are connecting via WiFi using WPS, wait for the “Internet” LED to start blinking, then press the WPS button on your WiFi access point. Within 10–20 seconds, the blinking will stop and the “Internet” LED will light up solid.

If this is your first time connecting and you didn’t press the WPS button within the two-minute window, wait an additional three minutes, power off the station, count to 10, and power it on again. For the other two connection types (Ethernet or WiFi without WPS), the LED will not blink. You can find more information on WPS in the section titled “WiFi Setup Using WPS PBC”.

Final Setup steps

Once the “Internet” LED turns solid, wait another 2–3 minutes. Then, open a browser and go to http://rtkbase.local. Enter the default password "admin" and change it. It explained in “Base address. Change password. Shutdown"

Check that everything is working correctly, as described in the section “Checking Satellite Reception”. If you’d like, you can also set approximate coordinates, following the same instructions in that section.

Optional: Earning with Onocoy

If you want to earn cryptocurrency by contributing to the Onocoy base station network, refer to the detailed guide in “NTRIP Configuration for Onocoy”. If that’s all you need, your setup is now complete — Onocoy automatically determines the base station’s precise coordinates.

Other NTRIP options

If you wish to connect to NTRIP casters other than Onocoy, then you will need to enter precise coordinates using one of the methods in the “Determining Coordinates” section.

RtkDirect alternative

If you want to use RtkDirect instead, refer to “NTRIP Configuration for RtkDirect” for the full setup process.

Direct rover connection

• If you plan to connect rovers directly to your base station, configure the built-in NTRIP caster as described in “NTRIP Caster Setup”.

Built-in VPN

• If you need a VPN to access the station from outside the local network, set it up as described in the section “Built-in VPN from Tailscale”.

4G/5G USB modem

• If you want to connect to the internet using a 4G/5G USB modem, refer to the section “4G/5G USB Modem”.

Radio modem

• If you need to transmit data via a radio modem, configure the base station as described in the section “Connecting a Radio Modem”

Troubleshooting

If you encounter any issues, refer to the relevant section or consult “Troubleshooting”.

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Power Safety and Connection Guidelines

All connections — including the antenna, power supply, SD card, and Ethernet — must be made only when the base station is unplugged from the power outlet. If you connect the antenna while the base station is powered, you risk burning out not only the antenna power circuitry but even the GNSS receiver itself.

Why Power Disconnection Matters

This is a common issue with all GNSS receivers powered from the electrical grid when used with fixed outdoor antennas. The reason is that most power adapters produce a voltage of 110 volts (half the mains voltage) on the device chassis. The resulting current is very small and harmless to people. However, fixed GNSS antennas are often mounted on grounded or electrically bonded building structures — or may come into contact with them accidentally. Similarly, the Ethernet cable may be grounded.

Unfortunately, modern electronics are more vulnerable to voltage than current. And while lightning protection can suppress brief surges, it will fail against sustained voltage differences. That’s why, before connecting a fixed antenna or Ethernet cable, always unplug the base station from the wall outlet.

Obviously, this warning does not apply to portable antennas. They can be connected while the device is powered. If you're running the base station on battery power, it's also generally safe to connect everything — except the SD card, which should always be inserted or removed with the power off.

Why Fast Charging Is Dangerous

One more important warning: please do not power the station using “fast” USB chargers or USB hubs from lesser-known brands. “Fast” chargers—those using QuickCharge or Power Delivery technologies—supply higher voltages, often 20 volts or more. This voltage level can permanently damage our base stations. Chargers from unknown brands may not handle the switching between normal and elevated voltage correctly. For example, one of our customers charged an iPhone using a USB hub with Power Delivery, and then connected the base station to the same hub. The hub failed to drop the voltage, and as a result, nearly everything inside the base station was fried.

Antenna and SD Card Setup

First, you need to mount the antenna on the roof or a high pole. For details on antenna installation, refer to our blog. The key is to give the antenna as much open sky as possible and minimize reflected satellite signals. The antenna itself is sealed, but its connector is not. Therefore, it is recommended to seal the connection point between the antenna and the cable with heat shrink tubing or special self-vulcanizing tape.

Inserting the SD Card

If you previously removed the SD card, your first step is to insert it into the right-hand slot. The SD card should be inserted with the metal contacts facing away from you and toward the board. If the text on the enclosure is upright (not upside down), then “toward the board” means the contacts face downward, and the printed label on the card faces upward.

Antenna and Port Connections

Next, connect the antenna to the IN port (SMA type). The OUT port (also SMA type) is the output of the built-in signal splitter. You can use it to connect an additional GNSS receiver, for example, one used for GEODNET.

Station Type Considerations

If you haven’t yet reviewed the differences between advanced (wired) and budget (wireless) base stations, refer to the sections “Choosing a Base Station Type” and “Feature list”.

Advanced (Wired) Base Stations

If you're using an advanced (wired) station and connecting via Ethernet, plug the Ethernet cable into the left-hand port. Then plug the power cable into the USB Type-C port on the right. The two USB Type-A ports on these stations are native Raspberry Pi connectors and can be used to attach peripherals such as radio transceivers, USB Ethernet adapters, or USB 5G modems. The HDMI ports on these models are disabled

Budget (Wireless) Base Stations

For budget (wireless) stations, the power cable should be plugged into the PWR IN port. The USB Type-C port on these models is the GNSS receiver’s port. It's used in cases where you need a standalone GNSS receiver instead of a full base station. Additionally, this port allows you to upgrade firmware or perform advanced configuration of the receiver.

Final Steps and LED Indicators

The LED indicators on the front panel show whether the station is powered on, whether there is an Internet connection, and whether satellite signals are being received. Details about these indicators can be found in the “LEDs” section.
And finally — plug the power supply into an electrical outlet. The included power supply comes with interchangeable plug adapters and supports most outlet types worldwide. For detailed steps on what to do after powering on the unit, refer to the section “Getting started”.

Important Note After Power-On

Important: After first powering on the base station, do not turn it off for at least five minutes. During this time, the system performs initial setup and configuration of the receiver, which can take a little while.

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Wi-Fi Setup Using WPS PBC

Starting from version 1.7.8, ELT_RTKBase supports Wi-Fi Protected Setup Push-button Configuration (WPS PBC). You can read more about WPS on Wikipedia, but to put it simply: it’s a way to connect a device to a WiFi network by pressing the WPS button on the router and on the device. The button press can be either physical or software-based.

WPS Behavior in Version 1.7.9

Beginning with version 1.7.9, WPS on the device is activated only when there is no existing network connection. If the device is already connected to a network—whether via WiFi or Ethernet — WPS will not activate. To enable WPS, you need to disconnect Ethernet, place the device in a location where no known Wi-Fi networks are available, and power it on. When WPS mode is active, the base station will indicate it by flashing the “Internet” LED for two minutes.

So, if your WiFi access point has a WPS button, you can connect for the first time (or after relocating the base station) by powering it on, waiting for the “Internet” LED to start flashing, and then pressing the WPS button on your access point. Within 10–20 seconds, the flashing will stop, and the “Internet” LED will turn solid. If you miss the two-minute window to press the WPS button the first time, wait another three minutes, then turn off the power, count to 10, and try again.

WPS Behavior in Version 1.7.8

In version 1.7.8, WPS is available, but it’s not indicated by the “Internet” LED. If the base station has never connected to a WiFi network, WPS mode starts about 30 seconds after power-on and remains active for two minutes. During that time, you must press the WPS button on the access point. Because this version lacks visual feedback for WPS mode, the best thing you can do with version 1.7.8 is upgrade to a newer release. For details about updating to newer versions, refer to the section “Software Update”.

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LED

Here’s how the LED indicators look on both the wired (advanced) and wireless (budget) base stations:

Advanced	Budget

Purple LED – Indicates that the power is on.

Green LED – Indicates satellite reception.

• On advanced (wired) stations, it blinks when satellites are being tracked and remains off when there’s no reception.
• On budget (wireless) models like ELT0233 and ELT0633, it stays lit when more than 30 satellites are being tracked, blinks when fewer than 30 satellites are visible, and turns off entirely when there’s no satellite reception. The blinking pattern is calculated as 33 ms / andlt;number of satellitesandgt;.
• On the budget ELT0733, the green LED stays on when an autonomous solution is available.

Yellow LED – Indicates that the station has an internet connection. It blinks during WPS mode — see “WiFi Setup Using WPS PBC” for details.

Red LED – Lights up when the first (A) NTRIP server has successfully connected to the NTRIP caster.

Built-in Splitter

We are sometimes asked how the built-in splitter works and whether our design includes a power blocker.

Indeed, dual-channel splitters from lesser-known manufacturers often use a simplified design that includes only a power blocker. This saves the manufacturer a few euro cents but causes a headache for the user when choosing which splitter output to use.

We don’t cut corners on our customers. That’s why we use the full design, including a load simulator and protection circuitry. In this setup, one receiver powers the antenna, while the second receiver sees a simulated load. Both receivers detect current in the antenna circuit. This allows connecting geodetic receivers that monitor antenna current directly to the splitter.

Here is the antenna section schematic from our base station. You can request the complete schematic by emailing us at info@gnss.store. I’ve highlighted the load simulator so you can see for yourself how negligible the cost savings would be if it were omitted.

In the schematic:

• C9 – power blocker
• R4, L2 – load simulator
• D7, D8, D9 – protection circuitry

Frankly, companies that save money by omitting the load simulator often skip the protection components as well. The protection circuitry won’t replace a proper lightning rod, but it may save both your base station and the connected receiver if lightning strikes the rod on your building or a neighboring one.

The insertion loss of our splitter is specified in the datasheet for the BP2G1+. At GNSS frequencies, the splitter’s insertion loss is 0.4 dB. You lose about the same—or even more - at an SMA connector. Additionally, you lose 3.01 dB (i.e., 50%) due to the inherent signal division between two output channels; this is a fundamental limitation tied to the number of outputs.

As you can see, the datasheet includes tables and graphs. But what about the splitters from lesser- known firms? Do they provide graphs, tables, or even precise numbers? IMHO, the less information a manufacturer provides, the more questionable the quality of their solution. That’s exactly why we use splitters from the reputable firm Mini-Circuits and openly publish as much technical detail as possible.

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The device should be placed in a cool, dust-free, and dry location. Avoid direct sunlight, exposure to rain, snow, hail, and protect it from domestic and wild animals, birds, snakes, fish, and insects.

In addition to simply placing the unit “on a table,” advanced (wired) base stations offer several mounting options.

“Bent End Plate Bracket”

“Сlip On Plastic Bracket”

“Aluminium Extruded Mounting Bracket”

“DIN Rail Clip Kit”

“1U 19" Extruded Aluminum Rack Panel” This option comes with configurations for mounting one, two, or even three devices.

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Base Station Address on Local Network

At the end of the installation, RtkBase will display the IP addresses of Raspberry pi on the screen. However, there is another way for modern operating systems — the address rtkbase.local, which means the site can be opened as http://rtkbase.local.

Please note — you must type the full address as http://rtkbase.local. If you accidentally enter http://rtkbase.local, or just rtkbase.local, your browser may automatically attempt to use HTTPS. This will not work, because the base station only supports HTTP (not HTTPS). The HTTP protocol uses port 80, while HTTPS uses port 443 — and this port is not currently active on the device.

Unfortunately, this method only works inside your local network. That means if you're trying to access the base station from your phone, you’ll need to connect to the same Wi-Fi network and (ideally) disable mobile data to ensure the browser stays on the local connection.

Changing the Password

Log in to the site for the first time (using http://rtkbase.local as the address).

Enter the password “Admin”.

Click on Settings at the top.

At the bottom, in the “System Settings” section, find “Change Password” and enter the new password.

Click on the “Change Password” button and see the message on the screen. Now click on the “Log Out” button and log out.

You will end up on the login screen again. Enter the new password and check the “remember me” box.

You will be taken to the Status page.

Shutdown

You can turn off the device by disconnecting the power. However, the most gentle method is to press the “Shutdown” button in the web interface.

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Most users don’t need to read this section. But if your WiFi access point has no WPS button, or if you want to set a static IP address, or enable SSH access, this section is for you.

Reminder: Always remove and insert the SD card only when the base station is unplugged from the power outlet!

Configuration Using the Windows Application

The simplest way to configure the base station is to insert the SD card into your computer's card reader (running Windows), and launch the WinRtkBaseConfigure.exe application. You can find the application on the SD card, or download it from our GitHub repository using the provided link.

The app includes five configuration sections, which are described below. Check the boxes for the settings you want to change, then enter your values. When finished, click Save. The app will automatically detect the SD card and write the configuration to it. Then, reinsert the SD card back into the base station.

WiFi Network Connection

To configure WiFi, check the WiFi box and enter your SSID and password (key) in the Key field. If you're connecting to a hidden network, check the Hidden SSID box.

Adding a User

To add a user, check the user box and enter:

• LOGIN – the username
• PWD – the password (optional)
• SSH – the user's public SSH key (optional)

To load a public SSH key, click “Load SSH public key”, select your key file, and click Open. The app will suggest using your own public key (typically created in the “.ssh” directory when installing an SSH client), but you can select any key file.

Static IP for Ethernet

This section is for advanced/professional users only. Most home users can skip it.

To set a static IP for the Ethernet interface:

1. Check the Ethernet IP box
2. Set the mode to Static
   
   
3. Enter the following:

• IP address of the base station
• Subnet prefix (typically 24 or 16)
• Gateway address (for internet access)
• DNS server address

If your network doesn’t have internet access, leave the DNS blank. If your setup involves a direct connection from the base station to a laptop (no router/gateway), leave the gateway blank.

Static IP for WiFi

This section is also for advanced users. Most home users do not need it. Setting a static IP for WiFi works exactly the same as for Ethernet. Follow the steps described above in the "Static IP for Ethernet”.

Configuration via Text File

If you don't have access to Windows computer, or if you prefer to understand the configuration process in more detail, you can configure the base station using a plain text editor.

To configure the system, insert the SD card into a card reader and create a file named system.txt in the root directory of the first partition on the card (this is usually the only visible partition in Windows).

This file should contain parameter-value pairs, each on its own line, using the format: parameter_name=value

If the value contains spaces, the entire value must be enclosed in double quotes. You can use any type of line ending — both Windows-style (\r\n) and Linux-style (\n) are supported.

The system.txt file is processed at startup by the Base Station, and deleted from the disk after it is applied. You can check whether the configuration was applied successfully (or if there were any errors) by visiting the Diagnostic page of the web interface. Scroll down to the section related to the RtkbaseSystemConfigure service. See the section “” for details on how to open the Diagnostic page.

WiFi Standard

Different countries allow different frequencies for WiFi operation, so the standard is set by choosing the country according to the ISO 3166-1 two-letter code. For example, the string country=LV means Latvia. For the USA, you should write COUNTRY=US.

Connecting to WiFi

The SSID (name) of the WiFi network is set in the SSID parameter, and the key (password) for access to the network is set in the KEY parameter (which can be omitted). For a network with a hidden SSID, add HIDDEN=Y.

For example:

SSID=$'A B C'

KEY=$'`\"$\'\\|/\x7F\u0409\u00B6'

HIDDEN=Y

The SSID and password, as well as the user password, can be defined using ANSI C string rules, allowing the use of characters in both HEX and UNICODE formats.

Adding Users

To add a user, you need to set their login (LOGIN), password (PWD), and/or SSH public key (SSH) for the user who will log in to the Raspberry Pi.

For example:

LOGIN=abc

PWD=”1 23”

SSH="ssh-rsa AAAAB3NzaC1yc2ENT8cu66peHViuOU5CQF abc@comp"

Quotes for SSH are mandatory. The username is specified in lowercase Latin letters and can include numbers, underscores, and hyphens. The password can include HEX and UNICODE characters and must also follow ANSI C string rules.

Static IP

To assign a static IP, you need to set the static address of the Raspberry Pi, the subnet prefix (usually 24 or 16), the gateway address for internet access, and the DNS server address. Fields starting with ETH are used for Ethernet, and those starting with WIFI are used for WiFi.

For example:

ETH_IP="192.168.1.2/24"

ETH_GATE="192.168.1.1"

ETH_DNS="1.1.1.1"

WIFI_IP="192.168.1.3/24"

WIFI_GATE="192.168.1.1"

WIFI_DNS="8.8.8.8"

If you are using the Base Station in a network without internet access, do not specify a DNS. If your network has no gateway (for example, a direct connection between the Base Station and a laptop), do not specify a gateway.

Reconfiguration While Running

This section is intended for advanced users and rare professional scenarios. Occasionally, a base station is installed in a remote location where physically accessing the SD card is not feasible. For example, you may need to add a new user for SSH access, but the station is located far away.

In such cases, you can perform a live reconfiguration by downloading the RtkBaseConfigure.sh file and editing it using a text editor that preserves line endings — for example, Notepad++ or Far Manager.

First, review the section titled “Configuration via Text File.” Then, uncomment and modify the necessary lines in the script according to your requirements.

Once edited, upload the modified file to the base station using the manual update feature. To do this:

1. Go to the following URL: http://rtkbase.local/settings?update=manual
2. Click on the “Check Update” button.
3. In the form that opens, click “Choose file”, select the modified RtkBaseConfigure.sh file, and then click “Submit.”

The message will contain logs showing whether the configuration was successfully applied. After reading the message, click “Cancel” to close the window.

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Checking Satellite Reception

Open http://rtkbase.local in your browser and go to the Status page.

First, check that green satellite bars appear within 3–5 seconds after opening the Status page. Then make sure the bars are slightly moving — this indicates the data is being updated regularly. If anything seems wrong, refer to the section “Troubleshooting”.

Next, check the average signal strength (SNR). It should be 35 or higher. If it’s lower, check the antenna cable and connectors for issues. Then, check whether PPP mode is active. Built-in PPP works only with satellites having a signal level of at least 33. You’ll need at least 10 such satellites — otherwise, a PPP solution won’t be available. At the bottom of the Status page, you’ll see a map with your current coordinates marked as a blue dot, and your configured base station coordinates shown as a cross-hair. If no base coordinates have been configured yet, the map will appear with limited detail. Let’s fix that. Click the copy coordinates button on the right side of the page. Note: if PPP is not active, these coordinates may be inaccurate.

Now click Close and go to the Settings page.

On the right side of the Main service section, click the Options button. This will open the settings menu.

In the Base coordinates field, paste the coordinates from your clipboard (for example, with Ctrl+V)

Click the Save button, then click Options again.

Go back to the Status page — now you’ll see the entered coordinates as a cross-hair, and your current position as a blue marker.

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