What are their positive effects if we put on these yantras ?

If we are having a raincoat or an umbrella in heavy rain, we may become safe ?. If warrior have shield in battlefield, he may have less wounds. By this way we are surviving from these yantras. which we put on. In our different religious books, there is, that it will most survival thing if we can apply it.

The Rishi-Munies have given many a 'Mantra' for the remedy of ill-luck. This may act as a 'buffer' or a 'cushion' against ill-luck and minimise its impact.

But Anushthanam of these 'Mantras' should be carried out by a scholar otherwise it may not give desired results. Such Anushthanam gives desired results is a proven fact.

There are many a shloka in Chandi Patha, Shrimad Bhagwat, Shrimad Bhagvat Gita, Harivansh Puranam, Vishnu Sahastranam, Shiva Mahimna and certain 'chopais' of Ramayana too may change one's future, there is no doubt about it. But the point is that their Anushthanam should be carried on exactly as per the rules.

One may ask : a palmist or an astrologer himself is not the God, so how can he protect us from the bolt of misfortune ? Such persons should bear in mind that though they are not Gods, they can atleast see the oncoming 'tsunamies' and can warn you. At the same time they can suggest proper 'armours' or life boats' or life Jackets' which can save your lives in times of crises.