In no wind conditions? Then it doesn't result in an immediate failure. Most of that 400 lbs of preload was developed by pulling against and stretching the other two sets of guys. When the tension in
Towers are typically spec'd according to EIA/TIA-222. Prior to the current version (-G) , EIA/TIA-222 used "fastest mile" averaging for wind speeds. "Fastest mile" is a wind speed dependent averaging
You missed the Notice of Proposed Rulemaking. It's here: <http://hraunfoss.fcc.gov/edocs_public/attachmatch/FCC-06-164A1.pdf> The NPRM's only definite proposal is to modify the illumination rules in
Well, at least the current round is event driven, not the annual reappearance of a yet another TowerTalk urban legend. The FCC does have an NPRM that is open for public comment at present. Gee, there
Well, if it was a turkey, that'd be okay; I sure hope it wasn't a hawk. You really don't want to go messing with them migratory birds. At least you didn't leave any evidence behind. :-) The Migratory
Interesting that you should ask that. It would seem the answer to your question is yes, as the FWS has already had an electric utility successfully prosecuted and convicted for birds being electrocut
That's a query page that is fun to play with. Just one point to keep in mind: it's only >>> registered <<< antenna structures in that database, i.e. towers that require FAA notification. 73, Mike K1M
This version will accept 3 digit longitudes <http://wireless2.fcc.gov/UlsApp/AsrSearch/asrRegistrationSearch.jsp> 73, Mike K1MK Michael Keane K1MK k1mk@alum.mit.edu __________________________________
Actually the trend over the last several years has been the adoption of the International Building Code as the state building code, enforced statewide, in most states. See: <http://www.iccsafe.org/go
Hi Ted, When a manufacturer spec's according to a standard such as EIA-222, it's an 'average' wind speed. Survival loads are then computed by applying, among other things, a 'gust factor' on top of t
The original comment was in the context of using fixed direction Yagis in a stack. AFIK, W3LPL's 15m stack of 6/6/6 is on a rotating tower and the antennas in K3LR's 6/6/6 15m stack are independently
Consideration of stacking distance on the boom length comes about from trying to maximize free space gain by minimizing interactions when using a yagi design that has fixed element lengths and spacin
From New England, Europe subtends approximately 40 degrees of azimuth (35 deg (TF) to 74 deg (ZB) from Boston). There may be some differences in opinion over how much additional coverage is necessary
In detail, the question is a whole lot more involved than what is the -3 dB beamwidth of the smaller antenna versus the -5 dB beamwidth of the larger antenna. To perform a rigorous, quantitative comp
No, that's not it. The phasing concern with stacking dissimilar antennas is that the "zero phase" point the antennas will be in different positions horizontally. That requires an additional section o
One rule of thumb for stacking two antennas is H and H/2. With two tri-banders on a 90' tower, that's likely to be too wide a spacing on 10m. So a fall back rule of thumb is 30' to 40' spacing is usu
K7NV's finite element study <http://k7nv.com/notebook/towerstudy/towerstudy1.html> showed that the bending stresses at the base can be the limiting factor for a tower with the base section buried in
Glaciers rotate? In any case, glaciers move by deforming plastically (not elastically), not something I'd really want my tower base to do. 73, Mike K1MK Michael Keane K1MK k1mk@alum.mit.edu _________
Go here: <http://wireless2.fcc.gov/UlsApp/AsrSearch/towairSearch.jsp> enter you info and print out the TOWAIR determination for them. 73, Mike K1MK Michael Keane K1MK k1mk@alum.mit.edu ______________