Thanks for editing RogerDay, and thanks for the other helpful replies.
Usually this forum has been very very very helpful to me on anything from toilets to hepvo valve mods to waxing techniques but yesterday people rushed in to deride and mock (please do leave this sentence in) and I was taken aback. The forum members are here to help and celebrate each other, some may be accomplished in other venues but entirely new to trailers. (me) Why cut someone down?
I called etrailer and they immediately gave me the right answer. F150 from 2004-2008 (mine) is wired to about five feet from the back (four prong "thingie" I call it). He emailed me a diagram so someone can find that wire, which will be orange. That will connect my braking system to my battery. So I need five feet of 10 gauge. For any system.
The RF will allow me to avoid someone going into my dash. I am not keen on that. I don't particularly like people working inside my truck, and I would rather plug and play. I can also take it with me in the future, so not have to wire another vehicle ever, and if I want someone else to tow the casita
, they can just use this.
The RF would only get interference with a CB radio next to it, supposedly. It works on similar wavelengths.
Once I unplug the RF module on the tongue from the truck it's off. (I was initially concerned it might somehow always be on and emanating some kind of radio frequency I didn't want). For instance, I turn my ipad and cellphone to airplane mode at night when sleeping on the assumption we don't understand everything about EMF and caution can't hurt.
Etrailer also sent me a link to exactly what I need to purchase.
Either way I wanted a proportional system.
One of my problems this weekend was, the very handy and smart guy who offered to wire my truck didn't know the details about Ford above, and thought I needed much more wire, and then someone at autozone gave me the wrong 7 prong (I call it the thingie and he gave me what I call a female) and when I went back to get the correct one and return the cheap braking mechanism because I had decided to order a proportional one, I got a young guy who thought he knew better. Without my asking he left the store and looked at my truck and announced to me that I needed no wiring at all. As DH said later, everybody was half right and half wrong, He was so sure of himself, I gave in. I returned all my 10 gauge wire. He also insisted I didn't need a proportional system. Yesterday I returned everything. The store wasn't happy and the manager insisted her employee had been right. I guess they just wanted the sale.
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