u/Accurate_Pin_1659

Hey everyone,

https://preview.redd.it/41guez5wcr0h1.png?width=1680&format=png&auto=webp&s=fbd77b11793e998e58c223161f14007aa23c4c00

This is my first PCB design and before I send it to PCBWay I want to make sure I'm not missing anything obvious and see if there are any improvements I can make.

I'm building a standalone civil airband scanner (118–137 MHz) with 6 parallel receiver chains so it can scan fast. The basic idea is antenna → LNA → attenuator → 6x TA2003 mixers (each with their own Si5351A generated local oscillator) → 21.4MHz IF → Si4732 demodulator → audio out.

Control is handled by an ESP32 with a TCA9548A I²C multiplexer to talk to all 6 chips. Power comes from 2x 18650 batteries with a TP4056 charger and AMS1117-3.3 regulator.

Main things I'm unsure about:

1. The crystal filter between TA2003 AM_MIX and Si4732 AMI — I have a reference schematic but can't read the values clearly. What does a proper 21.4MHz IF filter circuit look like here?
2. Does the overall superhet architecture make sense for this use case?
3. Any improvements you'd suggest?
4. Anything obviously wrong that would stop it working?

Not looking for perfection, just want to know if it's worth printing and what I could do better. Happy to share the schematic.

Thanks

Hi, I’ve wanted to work at ESA for a long time and I’m still pretty young, so I’m trying to figure out what skills I should focus on. Is coding an important or required skill for electrical/Aerospace engineers at ESA? if so which languages would suit the best?