1 - PC-HFDL 635-3 HFDL Decoder (formerly PC-HFDL) 1.0.1 PC-HFDL 635-3 HFDL Decoder (formerly PC-HFDL) : A software utility that functions as an ARINC 635-3 HF data-link protocol, which enables you to receive transmissions from nearby aircraft and control stations License: Freeware OS: Windows Size: 221 KB KB