[jdboyd]

FWIW, making just 10 might drive that $13 price down quite a bit.

Although, it looks like 1 unit might be closer to $50 (at least for the suppliers I might use), but $150 for 10.

I think costs could be cut somewhat though. The USB->serial chip is nearly $6, but differently packaged it can be $4.40 for 1 or $3.99/ea for 10, and alternative chips that seem like they should be good enough can be cheaper still. The voltage regulator they chose is $1/ea for 500ma, while the one I would normally go to is $0.22/ea for 1000ma (dropping down to $0.13/ea for 10).

[pjc50]

If you're making lots, you could uncouple the programming interface which isn't needed while in flight, thereby saving both BOM and weight.

[sweetjuly]

The entire BOM is crazy. The USB to UART chip is wholly unnecessary if you simply pick a better (at an equal or lower price) ESP32-S3 module which has a USB interface.

I suspect this was designed based on things the author had in their cupboard as opposed to something that's reasonable for new designs.

[numpad0]

Does it need a regulator at all? ESP32 should be able to run on raw battery voltage, assuming the ESP is necessary. RealTek TX2/RX2 + PIC10/ATTiny10/CH32V003 could be even cheaper if user is okay with a dedicated transmitter.

[awestroke]

Which is your go-to voltage regulator?