After the first run of Ebulobo boards I’ve been assembling the parts to make some more nodes. I’ve updated the PCBs making sure that there is a ground plane and put some labels on the pinout. Like last time I ordered 10 RFM69HW radio modules and 10 ESP8266 modules from China via Alibaba. As always you have to wait 6 weeks for the slow boat delivery and finally they arrived last week.
I assembled a board, plugged it into USB power and attached my usb/serial board, I was able to flash the chip with the Arduino/UKHASnet firmware but found that it would only boot occasionally. The wifi was intermittent, only occasionally I was able to connect to the device. Touching the board the ESP8266 was hot to touch (almost burning hot). To test that it wasn’t a change in my PCB that was causing this issue I used my last v0.2 PCB (original Ebulobo) and had the same issue.
Closer inspection of the ESP8266 the board looks very similar though it does have a different chip antenna, the original ESP8266 03 modules have a off white antenna with RAINSUN printed while these have a white non-branded antenna. Googling I couldn’t find any images of an ESP8266 03 with a non-branded antenna (though I wouldn’t be suprised if there are only a few original pictures and everyone just copies them – like this one).
Its difficult to know if the modules are fake (there are a few rumours online that it might happen) or that they’ve changed the pinout resulting in my PCB not working properly. Would be interested if anyone has experience with this problem.
I’ve ordered some more ESP8266 03 modules from another seller so will see if these have the same issue.