Appreciate the comments - I sometimes feel like I am getting involved with voodoo when dealing with electronics

An update on the other equipment I have. All my flight instruments are legacy analog gauges. The Transponder is a Garmin GTX 320 which has only the db-25 connector which is currently hooked to my db-25 only connector on the King encoder.

Doess that throw any monkey wrenches into the mix regarding replacement of my encoder with a unit that does or does not have the db-9 serial connector?

I do need to comply with the ADS-B requirement - my location is right under a Class B veil & I do use control tower airports anyway. Trying to understand this stuff so I keep the expenditures as reasonable as possible but only with reliable equipment.

Sincerely,

Dave