The scale LOCK is on, so you can move the entire chart or zoom in and out and still keep the proper SCALING so the angles don't change.
The pitchfan is anchored to the bottom and the top. The 3rd anchor of the median is swung around on a circle (filled in) that has it's radius from the first 2 points. A smaller arc goes from the top to precisely where the 3rd anchor point touches the filled in circle. The smaller arc distance is copied and place on the intersection of the 3rd anchor and the filled in circle (at the bottom of the higher pitchfan). I used 17 divisions instead of 18 when determining the spreads (because it fit the points). If they just made the spreads go in a complete circle (360) for the pitchfan, it wouldn't be necessary to make a 2nd pitchfan. All the increments in the "format inputs" are 5 degrees. Just type in tan 5, tan 10, etc. until tan 45. All the spreads work away from the median center (black) which would be 0. This chart is scaled for right angles to show up. That's another story. It should bounce off the 1 arc at .7734 if I'm correct. I had previous pitchfans set at 7.5 degree spreads, but this is 5 degrees and keeps the angles within the 2nd and 3rd pitchfan anchors...which makes them spread evenly easier. What is the idea here? Make equal spreads spread evenly, but keep the angles within the 1st, 2nd and 3rd anchor points of the pitchfan. This allows the maximum number of divisions between the median lines.
The pitchfan is anchored to the bottom and the top. The 3rd anchor of the median is swung around on a circle (filled in) that has it's radius from the first 2 points. A smaller arc goes from the top to precisely where the 3rd anchor point touches the filled in circle. The smaller arc distance is copied and place on the intersection of the 3rd anchor and the filled in circle (at the bottom of the higher pitchfan). I used 17 divisions instead of 18 when determining the spreads (because it fit the points). If they just made the spreads go in a complete circle (360) for the pitchfan, it wouldn't be necessary to make a 2nd pitchfan. All the increments in the "format inputs" are 5 degrees. Just type in tan 5, tan 10, etc. until tan 45. All the spreads work away from the median center (black) which would be 0. This chart is scaled for right angles to show up. That's another story. It should bounce off the 1 arc at .7734 if I'm correct. I had previous pitchfans set at 7.5 degree spreads, but this is 5 degrees and keeps the angles within the 2nd and 3rd pitchfan anchors...which makes them spread evenly easier. What is the idea here? Make equal spreads spread evenly, but keep the angles within the 1st, 2nd and 3rd anchor points of the pitchfan. This allows the maximum number of divisions between the median lines.