Garmin 327 xponder question

[aterry1067]

So, there are two power inputs, pin 15 for power input, and pin 1 for avionics master input. If I don’t have an avionics master switch, does pin 1 still need to be powered? I’ve read the entire manual and unless I have overlooked it, it seems to assume that every airplane has an avionics master switch.

If pin 1 DOES require a power input, can I splice off of the main pin 15 power input, or should I run an entirely new power wire from the CB?

 

[Dravnx]

 

[aterry1067]