Each message starts with the Farsi word for “attention” followed by what is assumed to be some header information as two 5-digit groups. Then there is a set of 181 five-digit groups. Each message is padded out to take 20 minutes, and there are six messages in each transmission.

Direction finding has traced the signal to a US base near Stuttgart, Germany. In addition to using Farsi, Iran has repeatedly attempted to jam the signal, causing V32 to change frequencies a few times. There’s also a more recent, so far unidentified, jammer trying to block the signal.

In addition to direction finding, there is a surprising amount of information you can glean from the audio. The first few days of broadcasts had specific beeps in the background, which appear to be warning tones from a specific type of American military transmitter that warns the operator when encryption is not engaged. At first, a human read the numbers. Eventually, the station switched to using automated numbers. In addition, there have been a few times when Windows 10 system sounds have leaked into the transmission.

Previously, previously, previously, previously, previously, previously, previously, previously.

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