What you see is a circuit board, a battery (lower left) and the speaker lower right.
The story starts with how weak the speaker sounds. I thought some earphones might help but they didn’t; in fact, I could barely hear anything on earphones. Perhaps an obvious flaw in the earphone jack could be found. Opening the radio proved an adventure. One can see a rather substantial screw pillar on the lower right; this is coming from the back of the radio. Three screws came off with some effort, but the 4th screw just spun around with no effort. It turns out that the screw head was broken off (not by me), leaving the rest of a very long screw holding both parts of the case firmly together. The only solution that worked was to use a fine-tipped soldering iron to heat the screw enough to melt the plastic to release it.
Remarkably, the radio still works as you see it in the photo. The phone jack is soldered onto the board and leaves nothing obvious to inspect. I asked a question about fixing the earphone jack on the Si47XX for Radio Experimenters Facebook group, and got this reply:
Bluetooth transmitter and Bluetooth speaker is the simplist
If you look closely at my photo, there is the phrase “WiFi + BT Model” and an antenna is etched onto the board above the chip, leaving the question 0pen whether it’s already capable of Bluetooth or not. I put on V1.01 of the G8PTN software where I specify ESP32-S3, the chipset I have. The photo also indicates that the chip has 16 MB of flash memory (some have less).
