Strange Effects of Cheap Coax

I have wireless network that needs to cover a decent amount of ground. I purchased a cheap 33FT coax to allow me to move my antenna outside. When

I first tried this cable with a junkie usb Wifi device and lost about half of my signal. I told the company and they sent me a new one, which did the exact same. It wasn't unit till a couple months later when I had a new Wifi usb adapter that I tried the cable again but this time only lost 3-5db along the run. Surprised I used the cable with the new USB adapter.

Now the problem has come up again. I got a TP Link Access point and hooked it up to that same coax and it is loosing over 18db over the line!

So why is that some devices seem to work with this cheap coax and other hate it? I know my solution is better coax or a water proof box for my access point but I'm trying to avoid putting anymore money into this project.

Well no one seem to know the answer to my question. It turns out that cheap coax may have worked fine but the TP Link access point just wasn't very sensitive at all. Even when I placed it outside directly connected to the antenna it would not give me a reliable connection. The cable still show something like 12DB of loss over 33FT when used with that router. As opposed to 5 db or so with the dongle. Still odd, now I guess I just need to find a better access point.