Blue Bottle containing helium

Helium Bottle

Thermocouple Plug

TC Plug

WET 4 Twitter Bootstrap

GC Slider 1x3

Some nice hand drawn style flowchart symbols

Hand drawn flowchart

Standard Filter

Filter

Sparkfun Espressif ESP32 Arduino

Sparkfun ESP32 Thing

generic system block diagram symbols for wireless equipment, based on 2020 USITT Sound Document Recommendations v3

SBD Wireless v1

Intercom Headset

Headset

Clear Com Hot Spot Antenna

Hotspot Anttenna

system block diagram symbols for Yamaha products, based on 2020 USITT Sound Document Recommendations v3

SBD Yamaha v1