[Towertalk] Guy wires on a 20 meter tower

[Roger]

Hi all,
I am planning to erect a 20 meters high tower. I'd like to put the 
following antennas on top of it:
- Cushcraft A3WS 3 Element - for 12 & 17 Meters
- Cushcraft XM240 2 ele - for 40 Meters
- 80 meters inverted V

Alternatively, I may use:
- Cushcraft XM240
- Cushcraft X7
- a 5 element yagi for 6 meters
- 80 meters inverted V

I've already built/installed the 3 (very heavy) guy anchors on the ground, 
each at 16 meters from the base of the tower. As we don't have any 
Philystran distributor here, I am going to use EHS guy wire. So interaction 
may be an issue.

Considering that wind is not a real concern in our area, my questions are:
1 - how many EHS guy sections are recommended for this tower and at what 
heights?
2 - where can I find somebody to make the modeling of this system, so I can 
find the correct lenghts to break the guy wires in order to avoid interaction?

Vy 73 de Roger - PY1OL