Congratulations on your Minolta Hi-Matic 9. One feature that I really like on this camera is the guide number feature that allows the diaphragm and focus mechanism to couple for automatic flash exposure.
Unlike the guide number feature of the Canon QL17 rangefinder, the Minolta’s guide number feature is strictly mechanical and does not need a battery to work.
The Minolta’s guide number feature is very similar to the mechanical guide number feature of the Nikon 45mm f/2.8 guide number lens. Both have a metric guide number range of 10 to 80. The Nikon has 10 settings within that range. The Minolta has 7 settings within that range.