Recent News

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RF Explorer 3G+ IoT - Internet of Things modules available

We are happy to introduce the new RF Explorer 3G+ IoT modules, with direct support for Arduino and Raspberry Pi platforms.

These modules are cost-effective platforms to develop your own customized Spectrum Analyzer, Power Detector, RF activity alarm, RF sniffer, RF QA test bench, etc.

Programmability and network capabilities of the hosting platform enables remote control and diagnosis scenarios, fully automated RF alarm systems, advanced assistance for unattended detection requirements such as those of radio operators, cell towers and HAM stations. These modules are also small and low weight so you can add it onboard on any FPV plane or drone and use to scan the flight area to detect interferers, or measure antenna response.

RF Explorer 3G+ IoT boards are delivered in two configuration modes:

  • Raspberry Pi
  • Arduino and compatible boards (3.0 – 3.3V only)

We recommend Raspberry Pi mode for advanced usage and more powerful libraries, and Arduino for simpler, non-Linux software libraries related development.

For added flexibility, these two boards can be easily re-converted between modes by soldering a required connector:

  • Raspberry Pi Hat can be converted to Arduino Shield by soldering standard 0.1” male headers to the PCB
  • Arduino Shield can be converted to Raspberry Pi Hat by soldering a 26x2 0.1” female header to the PCB

Designed in this way, it is easy to reconvert the board to a different hosting platform with no extra cost if you have different needs down the road.

Furthermore, other platforms such as BeagleBoard, Chip, Chipkit, Teensy all them can easily control a RF Explorer 3G+ IoT by manually connecting it to standard UART port.


Where to buy RF Explorer IoT Modules

Currently available at SeeedStudio:

  • RF Explorer 3G+ IoT for Raspberry Pi: link
  • RF Explorer 3G+ IoT for Arduino: link

Most of our distributors will eventually have them available.


RF Explorer 3G+ IoT Specifications

  • Includes the advanced 3G+ MWSUB3G RF Explorer module
  • Frequency band coverage: 15-2700 MHz
  • Standard SMA 50 ohms connector
  • Advanced selectable internal input stage: Normal, LNA, 30dB Attenuator
  • Amplitude resolution: 0.5dBm
  • Dynamic range: -130dBm to +10dBm
  • Absolute Max input power: +30dBm
  • Average noise floor level (typical with LNA enabled): -120dBm
  • Frequency stability and accuracy (typical): +-10ppm
  • Amplitude stability and accuracy (typical): +-3dBm
  • All modules are factory calibrated
  • Frequency resolution: 1Khz
  • Resolution bandwidth (RBW): automatic 3KHz to 600KHz
  • Protected with resettable fuse
  • Power consumption: 100-500mW

For more details, please visit

Delta Markers available in new v1.15.1610

The new RF Explorer for Windows v1.15.1610 is available (link)

It comes with important enhancements and fixes, recommended for all RF Explorer users:

  • Delta Markers (Spectrum Analyzer and SNA)
  • Markes can be placed anywhere on a trace using mouse double-click
  • RF Data Sniffer (Beta)
  • Latest OpenGL and 2D libraries upgraded including several bug fixes
  • Fix for SNA tracking where sometimes reject first normalization scan with a warning due to low level signal (-80dBm warning). This is now resolved and you should be able to complete your normalization in one single step.
  • Better grid scale display with thicker lines for major data points
  • Performance improved in narrow scan display

Working with new Delta Markers

These are powerful tools to measure frequency and amplitude difference between two trace points. Usual workflows are Harmonic dBc measurements, relative channel transmission levels, noise figure, etc.

In this example above there are 4 markers defined as Delta (M2 to M5) and one Standard marker (M1). Any marker can be defined as delta from other reference markers.

To define a Delta marker, first select the main Marker ID you want to define Delta link with. In this example below, Marker ID 5 is the Main marker, and Delta reference is Marker 1. That means frequency offset and amplitude will be calculated on screen as M5-M1. The M5 marker can be defined as an offset frequency from Marker 1 in this example, -7.366MHz.


On the right panel, the marker information display all detailed parameters:

  • Standard amplitude absolute value for the marker (-104.5dBm)
  • Delta definition (M5 – M1)
  • Delta frequency: -7.366Mhz
  • Delta amplitude: -75dB


If there are additional traces on screen, such as Average or Max, each one will list its own amplitude delta.

The Markers Display Panel has been updated to highlight in bold the Main Marker ID and current Frequency, and indent standard and delta values for easier visualization.

Some examples below:


Selecting a Delta Marker

  1. To define a Marker Delta, you first need a standard marker enabled. As an example, enable Marker 1, we will use it as Delta marker later.
  2. Increase Marker ID to go to Marker 5, enable it at any arbitrary frequency
  3. Check the Delta Marker and set the ID to 1
  4. At this point, Marker 5 is linked to Marker 1 and will display Delta calculations automatically
  5. Define offset in MHz you want Marker 5 to be from Marker 1. For instance, set it to -1Mhz, or 15Mhz, etc. Changing the offset will redefine position for Marker 5 based on current position of Marker 1.


  • Special Marker 1 can be Delta Marker of any other, but it cannot have associated any Delta Marker by Offset. The reason for this is Marker 1 works as auto-peak therefore cannot be defined as reference of any other.
  • Markers defined by Offset use the value at the time of Marker definition, but does not update or keep that offset fixed if the Delta Marker changes frequency. For instance if you define Marker 5 at an offset of 5MHz of Marker 1, and marker 1 is currently at 100MHz, then Marker 5 will be located at 105Mhz. If Marker 1 moves to a different frequency later, Marker 5 will remain at 105Mhz, you can see the current frequency offset any time in the marker display panel.
  • Future upgrades will allow for optional dynamic markers where offset will be locked so Main Marker absolute frequency value can change accordingly to the Delta Marker.

Near field H-Loop antenna for RF / EMI / EMC diagnosis

We have been adding more and more specific antennas to our offering over the last few months, in order to help users get the best value from RF Explorer.

As you probably know, the right antenna at the right place makes all the difference. Directional, omnidirectional, narrow band, wide band, patch, cloverleaf are available for different frequency ranges at SeeedStudio and other distributors.

But all our available antennas so far are used to measure the so called "far field" transmissions. They are fine to measure and diagnose all sort of RF transmissions which are a few wavelengths away. But for a number of tasks, most notably sniffing and measuring components or cables in a PCB or electronic device, far field antennas are not good because lack enough resolution to determine with precision where the transmission comes from. Furthermore, a far field antenna will keep receiving RF radiations from all sort of external, distant sources and mixing the result with the nearby radiation being diagnosed.

To assist on that, RF guys use "near field" antennas. They offer way more resolution for close-by diagnosis, and are mostly unaffected by far field transmission. Unfortunately, most near field antennas cost several times more than RF Explorer device itself; They are used for very specific tasks and not sold in the mass market. So most cost-sensitive setups would not have access to near field antenna... or that was the story until now.


We are happy to introduce our first custom designed, fully calibrated, near field antenna at the right price. This first model is called RFEAN25 and is a very sensitive, compact and easy to use H-loop near field antenna. We fine-tuned prototypes and experimented ideas for more than 15 months. Thanks to this creative design, our lab testing show RFEAN25 is at least 10dB more sensitive in the range 20-6000MHz than other H-loop options in the market, at a much lower cost.

If you compare it with other near field competing antennas, you will see RFEAN25 is smaller and lighter, exactly what you need when space is constrained in a PCB.

We added a high quality semi-flexible RF cable which works as the handler of the antenna. The big advantage of this approach: you can shape the cable the way you want for the antenna to be located exactly where you need, in most cases with no need to keep it on your hand.

It is the ideal antenna for the tasks listed below:

  • Detect radiation: Easily determine the electronic component or PCB signal track creating a wanted or unwanted RF radiation.
  • Sniff and measure: Follow signal path in any RF or high speed digital circuit, with no need to actually contact the circuit itself.
  • Find bugs: Thanks to great spatial resolution, it is ideal antenna to check for RF bugs such as hidden cameras or microphones in a room.
  • Diagnose EMI: Check any electronic device for RF radiation limits. This may include a connector with leakage, a module creating interference in a drone or RC plane, an oscillator or crystal that may not be working at the right frequency, etc
  • Pre-compliance EMC testing: Help on finding possible sources of interference in a design before passing an expensive EMC lab test for approval EU / FCC.
  • Create interference: it can be used to introduce RF interference in specific areas of a circuit or device, to check on side effects as well as diagnose root cause of intermittent problems. Connect it to a Signal Generator and use CW or Frequency Sweep to check how your circuit respond.
  • RFEAN25 can be used with RF Explorer Spectrum Analyzer and Signal Generator. But it can be used with any spectrum analyzer brand, as well as oscilloscopes. It is DC decoupled up to 25V so pretty much risk free if makes contact with the PCB circuit under test.


 The RFEAN25 is available for preorder at 15% discount till mid-October, for only $23.

You will not find near field antennas at this price tag anywhere. Use Seeedstudio link here.

Other near field antennas will be available later this year, as a full 4-antenna kit with 3 popular H-Loop sizes and one E-Field size. But we will keep RFEAN25 as separated antenna option as this is the best multi-task near field antenna most users need. More demanding users may go to the full antenna kit, it will be available at a very reasonable price tag.


RF Explorer Sniffer - public Beta available

This major feature for RF Explorer Spectrum Analyzers is now available as public Beta release.

We have been working hard the last few months to embed a huge list of features, including the ability to create your own decoder Add-ins:

  • Capture OOK/ASK modulation data packets at any frequency supported by your device model (in the range 15-2700MHz)
  • Filter and trim noise out of the data capture
  • Included decoders for PT2264 remote controls and Oregon Scientific weather stations
  • Advanced zoom, contextual menus, text, configuration settings for sample rate and frequency.

There are so many features included, the only way to elaborate them is through an accompanying guide included in the software package.

Download available in the BETA area of the download page.

How the RF sniffer works

You can detect RF transmission and decode data either manually or automatically.

Most gadgets and devices like the ones depicted below can be easily captured and processed by RF Explorer sniffer tool:

The RF transmission would look like a train of pulses at first sight, but it can include a large number of unusable noisy data, as well as duplicated data packets transmitted by the gadget.

Thanks to RF Explorer Sniffer tool advanced features, you can easily remove unwanted noise and detect envelope digital modulated signal, so it can be interpreted according to available documentation or reverse engineering.

If the device transmit a protocol currently supported by one of the included Decoders, the RF Explorer Sniffer will do all decoding with a single click:

Using this extremely advanced feature, checking any RF transmission is now a trivial task.

Below is a fully decoded RF remote control data packet including address and data values when pressing button [1] of that particular remote control. A good example of use for this would be to adjust your remote control receiver to the right address to react to that remote control.

And this is an example of fully decoded Oregon Scientific Weather Station sensor transmitting 7.9C temperature and 55% humidity.

This useful tool enables RF Explorer models such as 433M (by a mere $99) assist you on debugging RF projects, detect wanted and unwanted transmissions and interpret any gadget at hand. As opposed to other tools available, you do not need to disassemble or connect cables to the RF gadget in order to detect what is being transmitted: your RF Explorer connected to a Windows PC is all you need for the antenna capture and sniff around!

Developing your own Decoder add-ins

By using a simple yet effective Add-in model, RF Explorer for Windows can be easily extended with your own Decoders.

You can develop decoders in any language, samples are provided in Python and C#, but others like Perl, VB, C/C++, Java and pretty much any environment you are familiar with can do the work just fine. The only requirement is to produce a command line tool, following certain convention for data communication between the Add-in and the RF Explorer for Windows tool.

Happy hacking!

RF Explorer v1.15 upgrade available

We are happy to announce the availability of the latest firmware and software for Windows, as a free upgrade.

It includes final release version v1.15 firmware for Spectrum Analyzer and Signal Generator, as well as v1.15.1607 latest compatible RF Explorer for Windows.

The major features include full support for Signal Generator Frequency Sweep, Amplitude Sweep and Network Analyzer.

On the Signal Generator handheld device this is fully supported with new advanced screen modes as depicted below:

  • Improved Signal Generator CW screen with GHZ/MHZ/KHZ indicators

  • Improved Frequency Sweep screen with G/M/KHz indicators and true start power level

  • New Amplitude Sweep screen with true power level indicators

We recommend all users to benefit from these new features and fully stable latest firmware v1.15 upgrade. Please download from our online repository.