Get Started

Getting started with WPSD is reasonably straightforward. This section will prepare you and your hotspot or repeater for use with WPSD.

There are three main parts of WPSD:

  1. Your radio Yes, you must have a digital-capable radio. The radio is responsible for the digital encoding and decoding the voice streams. I know you are thinking you should be able to do everything with the Pi or a computer. Technically, you can, but if you are capable of that, you don’t need to read instructions like these. The radio encodes your voice digitally and then transmits it as an FM signal to be received by your MMDVM modem.

  2. Your modem The MMDVM or “Multi-Mode Digital Voice Modem” you have probably seen talked about. It is generally supplied as a HAT or “Hardware Attached on Top.” The HAT interfaces with the General Purpose Input/Output (GPIO) pins on the host.

  3. Your host This is a single-board computer (SBC) such as a Raspberry Pi. The host runs the WPSD software, which handles the configuration, user choices, and Internet gateway tasks.

Another way of looking at this configuration is that there is a radio and a hotspot. The hotspot combines the MMDVM and the host, often in a case with (optionally) batteries and a display. Neither the batteries nor the display are necessary, of course. The batteries can help you be more flexible, and the screen is preferred by those who enjoy visual feedback, such as seeing the callsign of the person to whom they are speaking.

Where your audio actually goes

It’s worth being clear about this up front, because it’s the source of a lot of confusion later: WPSD never touches your audio. Digital voice modes like DMR, D-Star, YSF, P25, and NXDN are, as the name says, digital — your voice is encoded into data by your radio, and everything past that point (the modem, the hotspot, the Internet, the network you’re connected to, and the other station’s hotspot) carries that data, not sound.

        flowchart TB
    You["Your voice"] --> Radio["Radio (encodes to digital data)"]
    Radio -- "digital data, over RF" --> Modem
    Modem -- "digital data, over GPIO/USB" --> Host["WPSD Host"]
    Host -- "digital data, over the Internet" --> Network["DV Network"]
    Network --> OtherHotspot["Other station's hotspot"]
    OtherHotspot -- "digital data, over RF" --> OtherRadio["Their radio (decodes to audio)"]

Audio only exists at the two ends of that chain — inside your radio and inside the other operator’s radio. WPSD, the modem, and every network in between are moving data, not sound. Practically, this means:

  • Volume/gain problems are a radio problem, not a WPSD problem. If someone sounds too loud or too quiet, that’s your (or their) radio’s transmit/receive audio settings — there’s no volume or gain control on the WPSD side to adjust, because there’s no audio there to adjust.

  • WPSD can’t “fix” audio quality. Choppy or garbled audio almost always traces back to RF between your radio and modem, or a shaky Internet connection — not something in the digital data path itself, which is either received correctly or it isn’t.

Getting started tasks

We’ll approach getting you started with three main tasks:

Attention

Once you have your system installed and configured, it’s strongly recommended that you back it up and save the backup, along with your dashboard password, somewhere safe. WPSD has a comprehensive backup capability built into the dashboard. For help, see the Backup and Restore Configuration section under Maintenance Items in this manual.