new yagi install

Status
Not open for further replies.

N8DRC

Member
Premium Subscriber
Joined
Jul 20, 2003
Messages
966
Location
Grass Lake
My new 800 mhz yagi install I did this past weekend, both are fed with LMR-400 with N connectors..Rotor is mounted at the bottom of the tower..The tower is free standing I cemented some heavy duty angle iron 3 ft in the ground the pad is 2x2x3 the tower is 14 ft. with 20ft of total mast pipe..
 
Last edited:

N8DRC

Member
Premium Subscriber
Joined
Jul 20, 2003
Messages
966
Location
Grass Lake
Hello
Thanks, the bottom is a Wilson 301111 8 element and the top is a 7 element Kathrein Scala TY-900 yagi..Here are a couple more pictures..
 
Last edited:

SAR923

Active Member
Joined
Dec 19, 2002
Messages
1,511
Nice looking tower but a rotor at the bottom of 20 feet of vertical pipe seems like an awful lot of resistance for that rotor to overcome, especially with ice and wind loading. I'd try to move the rotor up closer to the antennas if I could.
 

N8DRC

Member
Premium Subscriber
Joined
Jul 20, 2003
Messages
966
Location
Grass Lake
Ryanco said:
how much better are u geting 800mhz with the Yagi Wilson??
It improve my 800 alot, I really like that yagi, I have another that I am going to place at the top very soon..
 

N1BHH

Member
Joined
Mar 31, 2007
Messages
1,843
Location
Jackson Square, East Weymouth, MA.
Not a bad installation. One thing I noticed, no concrete base. I hope it don't come down in a storm, that wouldn't be too good, but there is minimal resistance.

As for the comment about the rotor and long mast, there are many installations where a rotor is near the bottom of an 80 foot plus tower. This is not unusual. There are some other installations which rotate the entire tower. You may notice that the rotor size dictates it's placement.
 

n8emr

Member
Joined
Oct 20, 2005
Messages
495
From the photos its hard to tell but the rotor doesnt look like its in the center of the tower. Also looks to be a very narrow tower.
 

N8DRC

Member
Premium Subscriber
Joined
Jul 20, 2003
Messages
966
Location
Grass Lake
The tower is in a cement base it is 3x3x3 ft. The tower is a small TV tower nothing big but big enough to hold the 2 yagi antenna's..You are right to rotor is off center a little I may change that later, but I really don't turn it very often..I like the rotor at the bottom for the weight reason's I can pull the one bolt out an bring the tower down myself to work on it on the ground..
 

rcvmo

Member
Joined
Aug 11, 2004
Messages
433
Location
Romulus, Mi.
the rotor doesnt look like its in the center of the tower

I was wondering the same thing myself.

Otherwise nice install.
I have a 440, 800, 900, and 2.4 beam altogether on a single mast and rotor. Lived up to the 50+ MPH winds Saturday Night.
rcvmo
 

mtindor

OH/WV DB Admin
Database Admin
Joined
Dec 5, 2006
Messages
7,489
Location
Carroll Co OH / EN90LN
SAR2401 said:
Nice looking tower but a rotor at the bottom of 20 feet of vertical pipe seems like an awful lot of resistance for that rotor to overcome, especially with ice and wind loading. I'd try to move the rotor up closer to the antennas if I could.
Show me the ice/wind loading. There'd be barely any ice loading or wind loading anywhere on the vertical pipe / antennas given their size. Sure the weight of the pipe may or may not be very substantial, but the downward force from the weight of the pipe/antenna is nothing that the rotor won't be able to handle.

Mike
 

SAR923

Active Member
Joined
Dec 19, 2002
Messages
1,511
I can see you're confused about the terms. Wind loading is the force exerted by wind when the antennas and mast are stationary. The more wind, the greater the resistance if you try to turn the antenna using the rotor. That's total wind loading. Ice loading is the same concept. Enough ice can build up on the antennas and mast to cause problems for stationary antennas. Trying to rotate the mast when the rotor may be frozen in position and the ice load may be up to several hundred pounds, depending on the thickness, can quickly lead to bent masts or a burned out rotor. In addition, I have no idea what the horsepower or Kw rating of that rotor is, not to mention it's off center.

My son is a structural engineer and he calculated out exactly what I'd need to put up for a 50 foot tower with a similar mast and rotor. Wind loading here is the bigger issue although we do get some ice. Ice and wind loading have to be more of an issue is Michigan. That convinced me an attic mount would be a far more cost effective idea. If I could get the total weight of the tower, mast, antennas, and the power rating of the rotor, as well as the exact height and surrounding terrain conditions, I'm sure he'd be willing to run some calcs again.
 

N8DRC

Member
Premium Subscriber
Joined
Jul 20, 2003
Messages
966
Location
Grass Lake
Hello
Well if there is alot of ice I don't even try to turn it as with all my antenna's, and the rotor is off 2 or 3 inches from center like everyone has pointed out, I am going to fix that very soon..Thanks for the comments though guys..
 
Last edited:
Status
Not open for further replies.
Top