This project uses an ESP32 processor to display the 32x24 temperature readings on a 1.69" lcd. Becuase a fast refresh rate is important, an ESP32-S3 was chosen becuase of the number of gpio pins needed for the 8-bit bus lcd. I'm a big fan of compact designs and was able to easily fit all the parts on the backside of the display. The only two i2c devices on the board are the sensor and LiPo battery monitor. The TFT_eSPI graphics library is my favorite to use in all projects for it's ease of use. Previous revisions used a chip antenna that was difficult tune but the pcb track antenna is working well. A nano VNA off aliexpress and youtube videos so far has been a great help. It turns out a 50ohm antenna track and properly tuned antenna (green curve) using a smith chart is not enough.
Getting the swr correct was needed but adding or removing copper to the tail of the antenna.(yellow line)
I know nothing about antenna design but after a lot of trial and error, youtube videos and help from others, 95% of my failed antenna designs are now working.
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