Multiple Batteries - Analog ground issue

Hello,

I have 2 batteries, and when I have them both connected I am running into a lot of interference with the analog pressure sensor I am using.

I have to power the SIM7000 directly and am using the USB port with a solar battery for the Arduino Mega.

Does anyone know how I can stop this interference?

Thank you for reading.

Matt

Image from Original Post so we don't have to download it. See this Simple Image Posting Guide

...R

It's a nice photo but I can't see anything in it relevant to your problem,

Please make a pencil drawing showing how everything is connected and post a photo of the drawing. Please DO NOT use Fritzing.

...R