[NLRS] Looking for advice about tower interaction with 902, 1296 and 2304 antennas

[Todd Sprinkmann]

  Hello from EN63ao,

  I am going to be putting up a 2nd tower here 40 miles N of Milwaukee so I can get on 902, 1296 and 2304 by summer.  This tower is going to have to look through my existing tower from a distance of 40'.  The new antennas for 902, 1296 and 2304 will be at 65', and again, they will be 40' from the existing tower where I have beams for 50 thru 432.  

  I am looking for anyone who has direct experience with how affected microwave signals are when they look thru another tower.  

  What these 902, 1296 and 2304 antennas will be seeing is a 26" square section of Rohn SSV that is 40' away.  The beams on the existing tower are up between 100 and 115', so that shouldn't be part of the equation.  Simply going to have to look through the 26" wide tower.

  I haven't installed the new tower yet.  I want to position it as intelligently as possible.  That's why I'm posting this question.  

  I can say with certainty that the new tower will have to look thru the existing tower on a heading of somewhere between 210 and 260 degrees.  I've spent a lot of time accounting for known uv stations to my SSW thru WSW.  As well as accounting for the precise headings where grid squares intersect in those directions.  (Don't want to lose any potential rover contacts, hi!)  I've also plotted what headings cities like Des Moines, Omaha, KC, and even St. Louis and the Dallas/Fort Worth Metroplex are.  If the potential interaction (at a distance of 40') is only say 5 degrees or so of beamwidth, I should be in fine shape with the new tower aimed at the existing one on a 240 degree heading.  But before I commit to that, I would like to hear a range of opinions.

  If it is important to know what antennas I am going to do on the proposed microwave tower, they will be a pair of 33 els on 902 and a pair of 45 els on 1296, stacked vertically on either side of a 1" H-frame.  The 2304 will be a single 76 el blowtorch.  I'm assuming the single 76 el on 2304 will be on a mast that should be about 15' long.  I'm also going to add a pair of new 432 beams on this mast with the single yagi for 2304.  Oh, and I plan on continuing to be a SOLP in the contests, so I will be at 10w max on 902, 1296 and 2304.  Antennas should be fed with individual runs of 1 5/8" hardline, and the runs will be about 70' each.

  Hope this is clear; if not, feel free to ask me to clarify.  

  Thanks for your time and look forward to working as many of you as possible on the bands this summer and fall.

  Todd  KC9BQA  EN63ao, 40 north of Milwaukee.