View Full Version : Mountain shadow
Miss1sapp
7-Apr-2015, 4:45 AM
Our place in Northern Idaho is in a mountain shadow blocking all but the northern TV tower. Along with the mountains we have a lot of very tall pine trees. We would be happy with any TV station.
Could anyone offer any advice on choosing an antenna that would help with this issue? We were able to pick up the signal a few times while temporarily holding a outdoor antenna but were unable to sustain the signal when it came to mounting the antenna permanently. We would like to get an Omni directional to see if this would help offer some forgiveness on the exact tower location.
http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3df1f00514f52e54
Thank you for reading!
Tower Guy
7-Apr-2015, 11:24 AM
You need an antenna with as much gain and directivity as possible. An omnidirectional antenna won't work for you.
Start with a 91xg and a TVPRAMP-1R. Aim the antenna at 15 degrees, and then try for a stronger reflection in that general direction. Next, try various heights as low as 18 inches in locations that are clear toward the north. The goal is to find an aim and height that works for as many of the low power stations as possible. Be prepared to permanently mount the antenna at extremely low heights. Next get a VHF antenna for ABC installed in a more normal location and couple it to the UHF antenna using the VHF input of the preamp.
ADTech
7-Apr-2015, 11:33 AM
An omni is actually the exact opposite of what is needed for the best chance in a nearly impossible situation. Yo want a very directional, very focused antenna that can zero in on whatever signal might be there.
First off, the mountain almost always wins. When you get double teamed by mountains and trees, your already meager odds plummet. Do not get your hopes up, that is a dismal forecast and your description of your surroundings reinforces my pessimism.
Now, with expectations properly sent to the basement, a question or two:
1. Did you use the "accurate method" of getting your location and plot (precise) or did you use a standard address look-up (often wildly inaccurate)?
2. Using the accurate method, click on the box foe "show lines". Can you manipulate the balloon marker to a location that is tree-free in any of the potential directions?
Tower Guy
7-Apr-2015, 6:59 PM
Next, try various heights as low as 18 inches in locations that are clear toward the north. The goal is to find an aim and height that works for as many of the low power stations as possible.
After more careful review of your location on the South side of Twin Lakes, I'd try aiming slightly West of North (toward the tops of the visible mountains near Spirit Lake) with the antenna within 10' of the shore and located 4-7' above the water level. This height is intended to aim the main beam of the antenna upwards toward the top of the mountains.
vBulletin® v3.8.11, Copyright ©2000-2025, vBulletin Solutions Inc.