On this site are some Yagi designs for VHF and UHF. Most of the designs are from a German ham, Martin Steyer DK7ZB. His designs are very popular in Europe. The dimensions are given in metric, some are in English. It is easier to get an accurate measurement with metric than English units. Measurements become more important at higher frequencies. It is easier to measure 1022 mm than it is 40 7/32”. At 70cm it is very important to be exact if you want the maximum performance.
Some of the designs I have chosen are for a driven element impedance of 28 ohms. This impedance give better gain and patterns than 50 ohms. It is easily matched to 50 ohms using 2 - 1/4 wavelength of 75 ohm coax in parallel. The Driven element is a simple dipole (easier to construct & match). The tubing in the design is metric, below is a table to convert metric tubing into our tubing sizes. Most of the time the only difference in the design is the bigger tubing is a little shorter (positions are usually the same.)