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Has anyone done Gerbers for EmonTx + ESP8266?

Hello,
I see that there is now an EmonTX with an ESP8266 integrated for sale in the shop, includes an external Wifi antenna and all, very nice.

This is exactly what I’m looking for but I need a different form factor so i’ll need to order my own i think from jlcpcb or the like.
I’ve had a look on the hardware github but I don’t see any gerbers for this new variation.
Does anyone know if this is in the pipeline ? I have a mate who can do circuit design so i don’t think it’ll be a big deal for him.
Best regards /Colm

I see that the EmonTX with an ESP8266 is no longer in stock. Anyone know when it will be back ?

Best regards / Colm

@Gwil might know.

Interesting, thanks. Shame it is hidden away in development boards…

Are you sure it’s a new PCB? It looks like a standard emonTX 3.4 with the battery holder removed and a Huzzah ESP8266 added in it’s place…

Even more so as it states “WiFi adapter easily slots in and out for use with a USB to serial UART programmer.” which makes it seem like it’s connecting to the same pins an external Huzzah ESP8266 would attach?

I can’t see anything that suggests an external WiFi antenna either :confused:

The emonTx V3.4.3 PCB layout has an extra “FTDI” connector, as you (@langers2k) suggest where the battery box used to be, and wired in parallel with the normal FTDI programmer connector, except that Tx and Rx are swapped over to avoid the need for the header pins to be cut and bent to effect the cross-over, as when the ESP8266 was mounted on the ‘programmer’ FTDI header:

I don’t believe the ESP8266 is capable of using an external Wi-Fi antenna. I suspect you
(@carbontracking) mistook the standard ISM band antenna.

Thanks for the clarification. Indeed I was incorrect about the wifi antenna.

So I think that an ESP8266 board like this one on Aliexpress with an external Wifi Connector would do the trick.

You might well need to reprogram that, as it won’t have the OEM software in it, and you might not be able to use the emonTx’s case. You also need to be aware that the ESP8266 sends spurious data TO the emonTx that has resulted in it getting recalibrated - in some cases the calibration constants were set to zero, resulting in zero values being output.

Hi @carbontracking. We are out of stock of ESP8266 modules. I will let you know when we expect to get more. The emonTx board is the same - with the jumper removed, since you will need an additional power supply when using the wifi adapter.

If you wanted to order an emonTx separately, we would happily add the female header for the wifi adapter if asked prior to shipping.

Robert has mentioned the reason above, and you can see it in the photograph in his post: we do not connect the Tx pin on the ESP8266 to the pin marked Tx on the emonTx.

If @carbontracking is going to use

then surely it will need to be external to the emonTx housing due to the way the antenna is mounted?

Sorry, I should have checked it wasn’t a HUZZAH ESP8266 module. Yes, mounting it externally looks like the way to go.

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