The top one is called akathaha chakra. This is to test the suitability of mantras to an individual. There are 16 squares. Take out the first letter of a practitioner’s name (in Sanskrit) and the first letter of mantra that is to be initiated. In mantra OM should not be taken into account, as all mantras begin with OM. In the chakra, squares from top to bottom are taken as rows and horizontal squares are taken as columns. Blocks containing the first letter of the name and the first letter of mantra should be taken. The block in which the first letter of the name appears is called as name block and the block in which the first letter of the mantra appears is called as mantra block. Now count the number of rows and columns from the name block to mantra block. The four blocks in the same row as the name block are called siddha (mantra fructifies after prescribed number of recitations). The four blocks in the second row are called as Sadhhya (mantra fructifies only after recitation of double the number of prescribed recitations). The four block in the third row are called susiddha (mantra fructifies if half of the prescribed numbers are recited) and the four blocks in the last row are called ari (provide only evil results). Similarly count the columns from the mantra block to name block. This way we get 16 combinations. Only certain combinations give fructification of mantras. For example susiddha-sushddha combination gives immediate fructification of mantras. Ari-ari combination is said to be dangerous and might even kill the practitioner himself.
Janana yantra is used to worship matrka aksharas in a ritual called ‘janana’ of a mantra or the birth of a mantra. Each mantra is to undergo certain rituals in order to derive benefits from mantras. This has been already discussed by us in detail under ‘fructification of mantras – part II’.