FPV Reference

https://us.banggood.com/Wholesale-Warehouse-Eachine-TX526-5_8G-40CH-25MW200MW600MW-Switchable-AV-Wireless-FPV-Transmitter-RP-SMA-Female-wp-Usa-1083642.html

 

DYS 4in1 F20A ESC Overview

 

Lenses:
2.1mm = 158˚
2.5mm = 147˚
2.8mm = 130˚

Image result for different sma connectors

 

Marsh:
Martian ii frame
racerstar 2205 2300kv
upgrade to 2205s 2600kv (https://www.banggood.com/4X-Racerstar-Racing-Edition-2205S-BR2205S-2600KV-2-4S-Brushless-Motor-For-210-QAV250-280-FPV-Frame-p-1101510.html?rmmds=search)

camera: FOXEER Arrow V3 2.5mm 600TVL HAD II CCD PAL/NTSC IR Block Mini FPV Camera Built-in OSD MIC
https://www.banggood.com/FOXEER-Arrow-V3-2_5mm-600TVL-HAD-II-CCD-PALNTSC-Mini-FPV-Camera-Built-in-OSD-MIC-p-1121696.html?rmmds=mywishlist