I'm a newbie in these waters so please bear with me and my potentially dumb question.
I have a schematic of a device I want to build that I'm trying to decipher and source the parts for. In the parts list, aside from usual things and codes that are easily google-able and easy to find, I have also the entry "TRICOIL". I've tried google and some forums but no luck. Does anyone know what this part is and what it's called in the language of electronics retailers? I attach a snapshot of the schematic for easier understanding.
Thanks in advance and cheers!