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The Proclaimer®

Strange devices from a strange land
Posted on Tue, 24 Jun 2025 18:18:00 MDT by Aaron Bieber
Tags: Electronics, Firmware, Music

Recently I went to a thrift store and found an interesting device. It’s called the “Proclaimer®” from a company called “Faith Comes by Hearing”. The device stood out to me because it has:

  • A solar panel
  • Dynamo
  • USB-C
  • µSD card
  • Audio controls

It took me a bit to realize what it was. Especially because when I turned it on I heard a language that was very strange to me. Turns out it’s a Bible audio device. This model has the bible in Ndau – a language spoken in Zimbabwe.

I pulled out the µSD card to see what the files where. My hope was that they were just MP3, but it turns out they are an encrypted audio file with the extension “.smp”

I am very impressed by the effort put into a “Missionary in a box” device like this.

Components

Chips

  • ATJ2157 FP51AMQ 36K: Audio processor
  • cFeon Q32C-104HIP X20Q101 2248HLB: Flash storage?
  • XA5002 1 7042 HBRDHA: Audio amp
  • Unknown: Near the power control components
  • Unknown: Near the power switch on the crontrol interface side of the PCB

Dynamo

Gears are exposed to the inside of the case, and grease seems to spatter about a bit.

Solar panel

6.2V output in direct sun light.

Speaker

Big old school speaker. 4Ω 2W.

Battery

3.2V 2400mAh LiFePO4 (Mottcell)

Notes

[2025-06-17 Tue]

  • Thanks to a friend, the files can be “decrypted” using 1 byte xor with 0x57.

[2025-06-14 Sat]

  • USB-C seems to only be for power.
  • There are “RX” / “TX” pads above the ATJ2157.

Links

  • smp2mp3: potential tool to encrypt / decrypt the files. It seems I would need to extract the private key from the device.
  • actions_flash: a tool for dumping the firmware from ATJ chips.
  • audiocube: a python tool for encrypting / decrypting .smp files.

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