KPWI LPFM 91.1 Salem

Viewing 7 posts - 16 through 22 (of 22 total)
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  • #39172
    Andy Brown
    Participant

    All metal water towers suck as FM antenna sites because of reradiating. Most folks that attempt to use them mount their antenna on the side, not at the top, and at the FM wavelengths the signal sees a giant reflector. Not a problem with directional cell antennae because of little radiation to the back and much much smaller wavelength.

    If the top is accessible and leasable (usually not the case), most of the problem disappears although if the tower is big enough in diameter, it can contribute to depression angle reflections which may add multipath.

    #39173
    Alfredo_T
    Participant

    A picture is worth 1,000 words! 🙂

    #39174
    cbaravelli
    Spectator

    “can” and “may” sure helps to clarify and the second photograph proves the point. FM, cellular and 700 mHz Public Safety.
    Now show me a quality VHF antenna which will radiate ANY SIGNIFICANT POWER 60 degrees off vertical axis. Or even the cheep ones. Just use a mast.
    There are two non-American english language very low power FMs in the area that broadcast atop water towers. Local community support is essential and these “radio rats” cover their respective communities well. As stated, municipal water district managers and directors are the major issue.

    #39177
    Andy Brown
    Participant

    It’s not the water district guys, per se, it’s the insurance folks and their underwriters. My personal experience talking with some of these municipalities is that they don’t want the business unless it pays really well, the kind of money Verizon, AT&T, et. al. have to spend. They also are allergic to anything off of the catwalk without a ton of assurances and proof of insurance for an installation. It’s a lot of red tape and cost for an LPFM with no inside connection.

    What two local LPFMs are on water towers?

    #39178
    Broadway
    Participant
    #39183
    Andy Brown
    Participant

    Looks like they’re already raking in some bucks, but as I said, they can’t move that far. Second thought, it’s probably City Of Salem stuff so not a cash cow.

    Also with respect to Randy’s post, the distance from the KPWI site to the translator in Scio is 44 km, required is only 24 km, so moving 6 km towards the south won’t be a conflict.

    http://bit.ly/2oq4PVO

    https://recnet.com/73807

    #39185
    cbaravelli
    Spectator

    http://radiostationnet.com/fm/oregon/KPCN-LP/
    Gimme a chance and I’ll load KVGD-LP AT site photo (Dam Gerglearth).

Viewing 7 posts - 16 through 22 (of 22 total)
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