Covert Signal CTF Challenge

Story:

In the world of espionage, secrets are everything. A master spy known as Olivia has left behind a cryptic message. She was renowned for using a unique radio mode, a technique known to only a few elite operatives.

Every morning at exactly 04:00, Olivia would send out her secrets using a special encoding technique. Her messages often contained subtle hints tied to the code 125. Hidden within these clues lies a crucial piece of intelligence.

Can you decode her message and uncover the hidden flag?

Challenge Description:

A flag encoded using a protocol specifically used in RF and amateur radio communication. Decode the message sent by the master spy, Olivia, and uncover the hidden flag. Pay attention to the subtle clues related to her name, the time 04:00, and the number 125.

Solve Path:

1. Download fldigi or other software that supports Olivia-4 125Hz.
2. Tunnel the audio from the WAV file using a virtual audio cable.
3. The actual challenge is to look for decryption clues. You may use resources like Signal Identification Guide or conduct research based on the story and hints provided.
4. Decode the output to reveal the flag.

Decode Output:

TTTTTTTTTTTTTBSidesTLV2024{RF_invest1gate-S0rcery}TTTTTTTTTTT

Flag:

BSidesTLV2024{RF_invest1gate-S0rcery}