Through hole technology is usually used for the electronic components that involve the use of leads on the components that are inserted into the holes drilled in printed circuit boards either manually or by the use of automated insertion mount machines. This technology has almost replaced earlier electronic assembly techniques. The through-hole mounting provides strong mechanical bonds when compared to surface mount technology techniques. However, the drilling process required for through hole mounting makes the board more expensive.Thru hole crystal oscillators are usually installed in the applications where size is not a critical issue and where wide range of frequencies are required. It features simplest manufacturing process and have more desirable temperature and electrical characteristics than surface mount crystals. Also, through hole crystals are used in more demanding applications that surface mounting crystals.The most commonly used industry wide standard package for a thru hole crystal oscillator is a 4-pin dip half size (Oscilent 320 Series) whereas the most common package for a surface mount device is 5x7mm Ceramic 4 pad device (Oscilent 430 Series). Thru hole mounting techniques are usually reserved for bulkier components such as electrolytic capacitor or semiconductors in larger packages such as TO220 that need the additional mounting strength.
