Outdoor FM antenna signal loss help

[rockin1jr]

Hi all,
I have an Antennacraft FM6 antenna mounted outside roughly 10-12 feet high (say 11 feet average).
My cable run (RG6 non quad shield), is 75 feet long roughly, and I lose the majority of all my upper frequencies. I had this same antenna mounted indoors and I got all of my Pittsburgh FM's clear, but outside, the very upper frequencies have way too much static.
What is the cure for this? I know a preamp would hurt more than help, from the research I've done.
I had a coworker tell me about a long wire run FM repeater, but I have no idea if this is actually a thing..or not.
Any help would be greatly appreciated.
Thanks,
Jim

P.S. - Ignore the red underlines on the FM Fool report, I was trying to aim the antenna for these 2 stations and no luck.

[rabbit73]

I suspect that electrical noise interference has raised the noise floor which will mask your weak signals.

Is the coax grounded with a grounding block connected to the house electrical system ground to reject interference?

You can hunt for electrical interference with a portable radio that will tune the AM broadcast band. Tune to a frequency not in use at the low 550 end or the high 1600 end. You can also use the AM radio in your car or a portable radio that tunes the aircraft band which is AM. An FM portable is not suitable for noise hunting.

Your previous thread:
Preamp vs Distribution amp for outdoor FM antenna
http://forum.tvfool.com/showthread.php?t=15963

[rockin1jr]

It is electrical noise, I can hear it when I try to tune in one of those frequencies. And no, it's not grounded. It's just one straight piece of 75 ft RG6. I imagine I'm better off connecting a ground to the house system, vs having it going to a grounding rod? or does that not matter?
Thanks.

[rabbit73]

Usually better to connect to the house electrical system ground. For a temporary test I use a wire connected to the grounding pin of 3-wire plug inserted in a properly wired 3-wire receptacle or a cold water pipe with no plastic sections in it.

You might have to move your antenna if it is close to the noise source.

[rockin1jr]

I temporally moved the antenna back inside as I got more even reception inside, but it was mounted roughly 6-8 feet under the 91XG. But I'll try that, thanks.