AIP Sweden GEN 1.5 revision 10 August 2023. The biggest difference is that a Mode-S transponder is now required for all IFR flights.
For those aircraft that have an old Bendix/King KT76A the Trig Avionics TT31 Mode-S transponder is in most cases Plug-Play with the existing mounting tray and harness.
For those aircraft that have any other type of Mode-A/C transponder we recommend the Garmin GTX335 Mode-S transponder that when paired with an approved GPS position source such as a Garmin GTN650/Xi also enables ADS-B out. The optional Garmin GAE12 altitude encoder that mounts onto the GTX335 backplate is highly recommended and any old gillham code blind encoders can be removed.
For more information see following link: https://aro.lfv.se/Editorial/View/IAIP?folderId=4