TIPS & Suggestions










  • Reduced utilization of the Raspberry Pi 4 Model Rev 1.1 processor during using SparkSDR control software 



    • In the terminal, the command: sudo raspi-config
    • Position seven Advanced Options
    • Position A8 GL Driver
    • enter
    • Change G1 - Legacy to
    • G2 - OpenGL desktop driver (Fake KMS)
    • OK  
    N1MM+ focus setting for contest 







    Antenna Toggle Control for HL2: Current Solutions and Workarounds

    Currently, there’s no built-in solution in HL2 software to control the antenna toggle during reception (RX) or manage other peripherals directly from the front panel. In my view, the RX antenna toggle should be a core radio function, not reliant on external devices. As a temporary workaround, an Arduino and Raspberry Pi 4 (Pi4) duo is used. The Pi4 remotely manages the Arduino over TCP/IP.

    Note: The OpenHPSDR beta 3.50 test version includes front-panel control for this, but it’s still under development and not fully stable.

    For remote management—whether over LAN/WAN, between rooms, floors, a garden terrace, or a holiday cabin—the Raspberry Pi acts as a mediator. The Arduino connects to the Pi via USB, and the Pi is controlled remotely through TCP/IP over LAN or WAN. Alternatively, the Raspberry Pi alone can handle this using remote GPIO, provided the number of relays needed isn’t too high.

    What’s a Toggle?
    The toggle function lets you switch between the main antenna and a receiving antenna during RX. When the PTT (push-to-talk) button is pressed, it always switches to the main antenna.


    Script Code for Raspberry Pi and Arduino via USB

    Below is the script setup for linking a Raspberry Pi and Arduino over USB. It uses two parts:

    1. GatewaySerial: Uploaded to the Arduino.
    2. RelayActuator: From the MySensors library, with modifications.

    GatewaySerial Details

    Upload this to the Arduino after modifications. It allows remote communication with the Arduino via the Raspberry Pi over a network (local LAN or WAN/Internet). Changes from the original GatewaySerial script are highlighted (e.g., including the MySensors library).

    Modifications to GatewaySerial

    To integrate RelayActuator functionality, I made these tweaks:

    • Changed BINARY to LIGHT in the presentation function.
    • Set #define RELAY_PIN to the pin number of the first relay (e.g., your relay’s connection point).
    • Defined #define NUMBER_OF_RELAYS as the total relays used (e.g., I use 8).
    • Commented out #define MY_RADIO_RF24 with // since RF24 isn’t needed here.

    Hardware Notes and Safety Tips

    Caution with I2C Communication:
    When connecting a Raspberry Pi to an Arduino (except Arduino Due), watch the voltage levels. The Pi uses 3.3 V logic, while most Arduinos use 5 V (Arduino Due is 3.3 V). Mixing these without care can damage components.

    Using 5V Relays with Raspberry Pi:
    For small projects, I pair 5V relays with the Pi. The Pi’s GPIO header provides 5V at pins 2 or 4 to power relay coils, but the control logic stays at 3.3 V. (This is similar to using an MCP23008 expander.) The GPIO doesn’t directly drive the coil.

    Safety Recommendation:
    Use level converters or a simple Darlington transistor array for safer connections. This is critical even if your actuators or sensors don’t use pull-up resistors tied to open-collector outputs—some devices might have them built in.




    Modified code below: * The MySensors Arduino library handles the wireless radio link and protocol
    * between your home built sensors/actuators and HA controller of choice.
    * The sensors forms a self healing radio network with optional repeaters. Each
    * repeater and gateway builds a routing tables in EEPROM which keeps track of the
    * network topology allowing messages to be routed to nodes.
    *
    * Created by Henrik Ekblad <henrik.ekblad@mysensors.org>
    * Copyright (C) 2013-2019 Sensnology AB
    * Full contributor list: https://github.com/mysensors/MySensors/graphs/contributors
    *
    * Documentation: http://www.mysensors.org
    * Support Forum: http://forum.mysensors.org
    *
    * This program is free software; you can redistribute it and/or
    * modify it under the terms of the GNU General Public License
    * version 2 as published by the Free Software Foundation.
    *
    *******************************
    *
    * DESCRIPTION
    * The ArduinoGateway prints data received from sensors on the serial link.
    * The gateway accepts input on serial which will be sent out on radio network.
    *
    * The GW code is designed for Arduino Nano 328p / 16MHz
    *
    * Wire connections (OPTIONAL):
    * - Inclusion button should be connected between digital pin 3 and GND
    * - RX/TX/ERR leds need to be connected between +5V (anode) and digital pin 6/5/4 with resistor 270-330R in a series
    *
    * LEDs (OPTIONAL):
    * - To use the feature, uncomment any of the MY_DEFAULT_xx_LED_PINs
    * - RX (green) - blink fast on radio message received. In inclusion mode will blink fast only on presentation received
    * - TX (yellow) - blink fast on radio message transmitted. In inclusion mode will blink slowly
    * - ERR (red) - fast blink on error during transmission error or receive crc error
    *
    */

    // Enable debug prints to serial monitor

    #define MY_DEBUG


    // Enable and select radio type attached

    //#define MY_RADIO_RF24
    //#define MY_RADIO_NRF5_ESB
    //#define MY_RADIO_RFM69
    //#define MY_RADIO_RFM95

    // Set LOW transmit power level as default, if you have an amplified NRF-module and

    // power your radio separately with a good regulator you can turn up PA level.
    #define MY_RF24_PA_LEVEL RF24_PA_LOW

    // Enable serial gateway

    #define MY_GATEWAY_SERIAL

    // Define a lower baud rate for Arduinos running on 8 MHz (Arduino Pro Mini 3.3V & SenseBender)

    #if F_CPU == 8000000L
    #define MY_BAUD_RATE 38400
    #endif

    // Enable inclusion mode

    #define MY_INCLUSION_MODE_FEATURE
    // Enable Inclusion mode button on gateway
    //#define MY_INCLUSION_BUTTON_FEATURE

    // Inverses behavior of inclusion button (if using external pullup)

    //#define MY_INCLUSION_BUTTON_EXTERNAL_PULLUP

    // Set inclusion mode duration (in seconds)

    #define MY_INCLUSION_MODE_DURATION 60
    // Digital pin used for inclusion mode button
    //#define MY_INCLUSION_MODE_BUTTON_PIN  3

    // Set blinking period

    #define MY_DEFAULT_LED_BLINK_PERIOD 300

    // Inverses the behavior of leds

    //#define MY_WITH_LEDS_BLINKING_INVERSE

    // Flash leds on rx/tx/err

    // Uncomment to override default HW configurations
    //#define MY_DEFAULT_ERR_LED_PIN 4  // Error led pin
    //#define MY_DEFAULT_RX_LED_PIN  6  // Receive led pin
    //#define MY_DEFAULT_TX_LED_PIN  5  // the PCB, on board LED

    #include <MySensors.h>


    #define RELAY_PIN 22  // Arduino Digital I/O pin number for first relay (second on pin+1 etc)

    #define NUMBER_OF_RELAYS 8 // Total number of attached relays
    #define RELAY_ON 1  // GPIO value to write to turn on attached relay
    #define RELAY_OFF 0 // GPIO value to write to turn off attached relay


    void before()

    {
      for (int sensor=1, pin=RELAY_PIN; sensor<=NUMBER_OF_RELAYS; sensor++, pin++) {
        // Then set relay pins in output mode
        pinMode(pin, OUTPUT);
        // Set relay to last known state (using eeprom storage)
        digitalWrite(pin, loadState(sensor)?RELAY_ON:RELAY_OFF);
      }
    }

    void setup()

    {

    }


    void presentation()

    {
      // Send the sketch version information to the gateway and Controller
      sendSketchInfo("Relay", "1.0");

      for (int sensor=1, pin=RELAY_PIN; sensor<=NUMBER_OF_RELAYS; sensor++, pin++) {

        // Register all sensors to gw (they will be created as child devices)
        present(sensor, S_LIGHT);
      }
    }


    void loop()

    {

    }


    void receive(const MyMessage &message)

    {
      // We only expect one type of message from controller. But we better check anyway.
      if (message.getType()==V_STATUS) {
        // Change relay state
        digitalWrite(message.getSensor()-1+RELAY_PIN, message.getBool()?RELAY_ON:RELAY_OFF);
        // Store state in eeprom
        saveState(message.getSensor(), message.getBool());
        // Write some debug info
        Serial.print("Incoming change for sensor:");
        Serial.print(message.getSensor());
        Serial.print(", New status: ");
        Serial.println(message.getBool());
      }

    }