Here is what I would do for your backup system. I am assuming that at the peak of the roof on the underside is a beam (likely at least a 2 x 6). I would drill a hole through that beam. Put a fairly large eye bolt through the hole with a nut and large flat washers on both sides of the beam. Take a piece of heavy steel cable with loops at both ends and run the cable through some part of the tree or web and connect both ends of the cable to the eye bolt using cable disconnects. Have the cable with a little slack, but not very much. This is a variation on what we do with stage lights. Optionally you could put in 2 eye bolts in opposite directions. I would put the bolt(s) through the beam as close to the top as you do it and still have it usable for the purpose and fairly close to the wall of the house.
I'll probably get b*tch slapped for this since most on here are EDM fans. I bought my transmitter from HLLY. I got the 1w transmitter, which is WAY too much power than what anyone needs. The .5w is more than enough and has great sound quality. http://www.hllyelectronics.com/fm-transmitter/0.5w-fm-transmitter.html I also bought some cable locks for my controllers from Home Depot. http://www.homedepot.com/h_d1/N-5yc1v/R-202311744/h_d2/ProductDisplay?catalogId=10053&langId=-1&keyword=cable+locks&storeId=10051 Wrap them around my trees and bushes. If anyone wants to cut down my trees to get my controllers, then cut away. I hate those trees and bushes anyhow.
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