Why does each outer devta cover 11.25 degrees, and how are the pads marked?
The 32 devtas of the pishach bhoomi share the full 360 degrees, and 360 divided by 32 is 11.25. Mark North with the plot's actual tilt (for example 5 degrees), place Som devta centred on North with 5.625 degrees on each side, then mark every further 11.25 degrees with a protractor or a zoning chakra and draw those lines only in the outer ring. The 12 inner devtas follow an 18-54-18 degree split in each direction (27 degrees on each side of the direction line for the middle one), and Brahma sits in the centre.
Related questions
How do we find N1 to N8 and the other door padas on a map?
Use the zoning chakra shown on the first day, or draw it: from the centre of the map draw the four directions 90 degrees apart and the corner directions at 45 degrees, then halve again to 22.5 degrees and once more to 11.25 degrees, which gives 32 padas (360 degrees shared by the 32 guardian devtas). Starting from E1 next to the North-East line, go round clockwise from E1 to E8, then S1 to S8, W1 to W8 and N1 to N8, on the 81-pada grid. Practise this as homework.
If Google Earth shows 350 degrees, how should North be marked on the plan?
In a regular plot you can set the zero directly at 350 degrees when drawing the straight line. It is easier to think of it as a 10-degree tilt and set off 10 degrees, because that method works from whichever side of the plot you start.
If the built-up area is on one side, such as South and West, with the other sides open, how are the pishach bhoomi and devtas found?
Use the angular method taught in class. Whatever the tilt and whatever the shape, octagonal, pentagonal or regular, find the centre, divide the plan into pishach, manushya-dev and brahma bhoomi and mark the pads by degrees as demonstrated, then practise it from the recording.
My compass showed North tilted toward the North-East, and Google Earth showed 2.39 degrees. Is that also toward the North-East?
Not necessarily. A magnetic compass shows North directly, so its reading can be stated straight away, for example North 30 degrees toward East. Google Earth and the mobile app only show the heading of the line you draw, and North has to be worked out from it; a heading of 2.39 means North lies 2.39 degrees to the left.
Should directions now always be read by degrees?
Yes, always by degrees; reading directions without degrees was a mistake, and only the degree method shows the actual zones.
Will every map have a 10-degree tilt with North at the top?
No. Each map has its own tilt, 10, 12, 20 or 25 degrees, and North can be on any side. Measure the tilt with Google Earth and find which side is North at the site, from the client or from the North mark that most plans carry, although the tilt itself is not written on them.