If the antenna and feedline are not working at peak efficiency some of.
Improve swr metal roof.
This serves as a barrier to prevent the water from entering the home even after the primary barrier the roof covering system such as shingles or.
Basically this is a peel and stick type of material that is installed before the shingles.
A 36 width roof underlayment install with ring shank nails having a minimum 20 rings per inch a minimum head diameter of 3 8 thru 1 5 8 tin caps or ring shank metal cap nails having a 1 diameter and long enough to penetrate the deck per code.
While the swr measures 1 1 1 5 at the antenna it has always been higher at the radio.
Not an expert but the metal roof should block the signal.
Best bet would be to go with an outdoor antenna up on the higher part of the roof.
If your antenna is mounted down low on the vehicle like on the bumper or behind a pickup truck s cab the signal can bounce back to the antenna causing a high swr.
Often the critical frequency for nvis is below 40m like 5 mhz and down.
When we got a lot of snow recently the swr went to 8 10 or higher.
The feed line is lmr400.
The antenna then converts this rf energy into electro magnetic energy which is radiated into space.
What type of secondary water resistant barrier is my wind mitigation report referring to.
When you transmit you are sending radio frequency energy along your feedline usually coax to your antenna.
Cireofmi jun 14 2009.
I have a gp 6 2 meter 440 vertical mounted on a metal pipe that is attached to one end of a metal roof.
Swr or standing wave ratio is a measurement of antenna efficiency.
7 things to know before choosing a metal roof if your current roof is the root of your headache and maybe even a long list of costly home repairs consider these metal roofing pros and cons.
The sheet product itself runs about 1 00 sf.
To alleviate this keep at least the top 12 inches of the antenna above the roof line and position the antenna as high as possible on the vehicle.
Also try the indoor antenna by the windows.
What s directly beneath the horizontal antenna may impact nvis which is pretty much a 10 mhz and below propagation method and the metal roof might actually improve that if you work 30 40 60 80 meters but probably not notably.