Unfortunately, the Icom IC-705 multiband transceiver has only a single antenna port for all bands. This naturally has both advantages and disadvantages. Consequently, for operation via orbiting LEO amateur radio satellites, I looked for a suitable 2m/70cm Yagi antenna that would not require the additional signal loss associated with a diplexer. My search led me to a proven design by DK7ZB.
There are two versions available, with lengths of approximately 1.0m and 1.5m. For the sake of portability and ease of transport in my car, I opted for the shorter version; it features 4 elements for the 2m band and 5 elements for the 70cm band. The specified gain is 7.1 dBd (2m) and 8.09 dBd (70cm), respectively.
The aluminum boom I used measures 15x15mm, while the elements are 8mm and the driven element is 12mm in diameter. These materials are available at almost any hardware store.
The element mounts and the connection box are made of PETG and were produced using a 3D printer. An excellent design file for this is available on Makerworld.
Upon completion and testing with a VNA, the antenna immediately showed excellent resonance on both bands and a VSWR of approximately 1.1—guaranteeing a successful outcome.