FreqEZ v1.1 – Full and Minimized Console windows


FreqEZ – A Versatile Band Decoder

FreqEZ is a Do-It-Yourself hardware/software project that provides highly configurable Band Decoding and Remote Antenna Selection. For amateurs who use N1MM+ and DXLab logging software, FreqEZ will leverage those programs’ TCP/UDP broadcasts for antenna switching. For other amateurs, FreqEZ can connect to the BCD band outputs available from most transceivers. The FreqEZ software is free to all hams, and consists of a pair of programs that run on the Windows and Raspberry Pi Raspbian operating systems.

Watch a short (5 minutes) FreqEZ Overview video HERE

This software is copyrighted freeware. You can use, modify, and distribute the software provided that you offer it and any derivative works as freeware. Any commercial use must be approved in writing by the author.

This software controls equipment that could be damaged by said software. You are responsible for installing, configuring, testing and ensuring that the software performs properly in your environment. The author cannot be held liable for any direct, indirect, consequential or incidental damages to other pieces of software, equipment, goods or persons arising from the use of this software.
By downloading this software you accept the above terms of copyright and disclaimer.



The FreqEZ Parts List contains components that were intentionally selected as being inexpensive and globally available. Using popular sources like Amazon, eBay, Mouser and DigiKey, hams should be able to purchase all of the FreqEZ components for less than $100 (US).


FreqEZ is a pair of companion software applications that run on a Windows PC and a Raspberry Pi (RPi) single-board computer. The user interface and software configuration run on Windows; the remote antenna switching runs on a Raspberry Pi. These two companion programs communicate via Ethernet or WiFi using TCP.

The N1MM+ and DXLab Commander logging programs send UDP broadcast packets containing radio information that the FreqEZ Console receives and interprets according to the FreqEZ configuration settings. The Console creates command strings that are sent to the Raspberry Pi Controller, enabling any combination of up to 16 devices (i.e. antenna switches, band filters, receive antennas, transverters…). From DXLab Commander, that radio information is the transceiver frequency in the <Freq> field. From N1MM+, that radio information could be the transceiver frequency, or it could be the packet’s <Antenna> number field entered derived from the N1MM+ Antenna configuration table.

Key Features

    • Free software. You buy your hardware wherever you want
    • Inexpensive, off-the-shelf, readily available hardware. No custom hardware required
    • No DIP switches, diodes, solder-bridges. All configuration is via software settings
    • Manual antenna selection with simple mouse clicks in the Windows Console
    • Automatic antenna selection from network-based UDP packets or hard-wired BCD inputs
      • In N1MM+ – use the antenna numbers from the Configurer >Antenna table
        • Supports the N1MM+ Keyboard Shortcut for multiple antennas per band by toggling <alt>+F9
      • In DXLab or N1MM+ – use the Rx radio frequency from the UDP RadioInfo packet
      • Auto-magic switching (no re-configuration) from N1MM’s antenna numbers to DXLab’s Frequencies
      • Hard-wired method, for logging programs that do not support UDP broadcasts
        • Connect to a transceiver’s BCD output jack
        • OR… use BCD outputs from a PC LPT parallel port (supported by some logging programs) {ugh!}
    • Versatile, software-based configuration can activate antennas in SO1V, SO2V and SO2R stations
    • The Windows Console and the Raspberry Pi Controller communicate via WiFi or wired Ethernet connections
      • The Raspberry Pi controller operates “headless” – can be located anywhere
  • FreqEZ controls 16 discrete single-pole double-throw (SPDT) outputs
    • 16 SPDT relays provide “dry contacts” that sink (ground) or source (+12 vdc) in any combination
    • FreqEZ can be optionally configured as four BCD outputs for antenna switches requiring BCD signals
  • PTT / Tx Inhibit line prevents FreqEZ from switching antennas while transmitting
  • Flexible, software-driven configuration for shack-specific customization

Parts List

Required and Optional Materials

    • The Console runs on a Windows PC with the following characteristics
      • Windows 7 or later
      • 8 GB of RAM minimum
      • 10 MB of disk space
      • Ethernet/WiFi connection
    • The Controller runs on a Raspberry Pi with the following characteristics
      • Raspberry Pi model 3 or newer with 40 GPIO pins
        • NOTE: Will not work on 512MB or single-core CPU RPi or Pi Zero
      • Raspberry Pi micro-USB power cable with power supply or PC as a power source
      • 8GB (or larger) microSD card with Raspbian operating system. Fast card (class 10) recommended
    • Band Decoder switches
      • Two SainSmart relay modules (or equivalent ) with 8 relays each. Models with 5 volt relays
      • Dupont rainbow female-to-female jumper cables for connecting the 40 pin RPi GPIO connector to the SainSmart relay modules. Recommend 30 total conductors, approximately 8 inches in length
    • Recommended hardware
      • Enclosure – to accommodate an RPi and two SainSmart 8 relay boards. Search Amazon or eBay for an aluminum extruded enclosure measuring 203mm x 144mm x 68mm – many sources and colors available
      • Mounting plate/tray inside the enclosure – rather than connect the hardware devices directly to the case, cut a piece of aluminum or perf board to slide along the guides within the enclosure. The tray should measure 7 7/8 long by 5 31/64 (5 1/2 inch may be too tight) wide. Aluminum plate should be .063 stock (see photos)
      • Stand-offs for mounting the relays and Raspberry Pi above the mounting tray. Many plastic and metal products are available on eBay and Amazon
      • Connectors and wire – as appropriate for connecting the enclosure to external remote antenna switches. Suggest D-sub 9 pin female for antennas, a D-sub 9 male for BCD inputs, RCA jack for PTT/Tx.
    • Optional voltage regulator – when using the Controller remote from the shack and +5 VDC sources
    • 12 volt to 5 volt regulator – for feeding the enclosure from a single 12 VDC power source. Useful when operating the Console remotely from the shack and a PC USB 5 volt supply is not available. Delivers 5 volts DC for the Raspberry Pi and SainSmart relays.


IMPORTANT: Please read and carefully follow the FreqEZ construction and assembly instructions in the manual.
Assembly instructions can be found in FreqEZhelp.pdf on the Downloads page  HERE

Connections (left/right, top/bottom): RCA jack – PTT inhibit, DE-9 male – BCD input, Raspberry Pi USB port, Raspberry Pi audio I/O, three DE-9 female – remote antenna relay control lines, +12 VDC connector

Rear panel in early construction phase, showing 9 conductor DuPont male-to-male ribbon cables. The male pins solder easily into the solder cups of the DE-9 connectors. The opposite ends of these ribbon cables connect to screw terminals on the SainSmart relays.

FreqEZ completed Enclosure with all cabling connected


Downloading and Installing the program
Current versions of FreqEZwin and FreqEZrpi software will be found on the Downloads page  HERE


If you have problems building or operating FreqEZ, look for answers on the FreqEZ reflector. You do not need to register, or login, or even have an account to search for a solution to your problem. (Although you will need to register if you want to post a new question)

FreqEZ @ can be found HERE.

     Larry K8UT, FreqEZ developer

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