[VHFcontesting] VHFcontesting Digest, Vol 34, Issue 22 (stacking distance 50, 144, 432, 144/440)

[steve d]

OK, now I am getting confused. I am hearing a LOT of different things here. Some of you say to stack the 144 beam above the 50 beam at the stacking distance for 144... That doesnt make sense because the stacking distance for 50mHz is MUCH more than at 144. Using the 1/2wl theory the stacking distances between the beams should be:

 

9.36' between 50mHz and 144mHz

3.25' between 144mHz and 432 mHz

And going by the lowest frequency on the dual band beam (144mHz) - 3.25' between that and the 432mHz beam. 

This comes out to a total of 15.86', then you have to add in some length to extend through the thrust  bering to the rotator. I am going to estimate the TOTAL length at 20 feet. Does this all sound correct? I want the beams to be as efficient as possible. 

 

Also, what does everyone reccomend as a mast? Array Solutions sells some REALLY NICE PE certified  masts, but they are VERY expensive. I was thinking about going to the plumbing supply store and getting a 2" galvanized steel pipe. Would this work? What should the wall thickness be? I calculated the windload at 6.675sq feet, so there isnt a whole lot of loading there.

 

Thanks for everyones help!! I hope to get back on the air this weekend as the VHF/UHF bug is biting pretty hard!!

 

Steve, KC8QVO

 

Steve, KC8QVO

		
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