Receiving Data

TRacer receives data using MT63 audio signals over radio, just like it transmits them. Tap Receive in the bottom bar to open the Receive sheet, which provides tools to monitor and manage received transmissions.

🎧 Live Monitoring

At the top of the Receive sheet, you’ll see a live text area showing what’s being received by the MT63 decoder. This shows the raw data being "heard" — helpful to verify that the audio is being interpreted correctly.

For best results, keep the radio and receiving device near each other, but do not hold the speaker directly against the microphone. The audio should be loud enough to decode clearly without distorting. If the signal is too quiet or too loud, Race Control can usually tell you over voice.

TIP

If the area is filled with characters like J@@@@@@@@@@@@, try toggling your mic off and on or moving your device slightly away from the radio to reset audio input.

When things are working, you should see data similar to:

<FILE 55 00A7>{8DEE}20250612224701:drops-6461be977c14d64592fa1ece.txt
<SIZE 13 5220>{8DEE}13 1 64
<DATA 21 57D2>{8DEE:1}8,1,DNS

Also note:

• A microphone icon appears at the top of the Receive sheet.

  • If it has a slash through it, TRacer is not currently listening.
  • Tap the icon (or the Start Listening button) to begin.
  • You must grant microphone access when prompted.

📥 Receiving and Tracking Data Blocks

Just like with transmissions, received data appears in a History list.

• Each received transmission is collapsible, showing:

  • A 4-character hash (based on station number and time first received)
  • A list of blocks: one Headers block and several numbered data blocks

If the Headers block wasn't received correctly, it will show in red. The app won’t know how many blocks to expect. If the Headers block was received:

• The app will display all expected blocks
• Green blocks = successfully received
• Red blocks = not received; should be requested again

⚙️ Importing Received Data

When a full transmission has been received:

• By default, TRacer will display a notification with an Import button
• Tap Import to add the received data into your local app records
• There is also a setting to automatically import on complete reception

TIP

If you're receiving a DNF list from race control, you’ll almost always want to import it. If receiving from another station, importing is optional. A station may import another station's data to see more of the race picture or help answer questions, but relaying a transmission does not require importing it first.

🔁 Relaying Received Data

Sometimes, your station may need to relay a received transmission to race control:

• After receiving a transmission, open the Receive sheet
• In the History, tap the item and select blocks just as you would in the Send sheet
• Tap the speaker icon to transmit the data again to net control

This uses the same process as re-sending your own data, but applies it to data you received.

🧯 Missing headers

If the Headers block is red, the simplest recovery is to ask for the whole transmission again. The headers include size information, so without a complete header TRacer may not know what blocks are missing.