• You can now help support WorldwideDX when you shop on Amazon at no additional cost to you! Simply follow this Shop on Amazon link first and a portion of any purchase is sent to WorldwideDX to help with site costs.

Vertical and horizontal beam mounting

Well, let me change my model to vertical and I'll get back.

How far do you have the mast set from the driver?

I just put the mast in the center of the boom, 97" I think is center. I'm on my phone now, but I probably should have looked at the assembly instructions for the boom-to-mast assembly point to be more accurate.
 
Sorry if I upset you 359. I just wondered why I never saw the results that you posted above. I wish I understood 4nec2 better so I could try and help us figure out why we are seeing the differences I noted.

I asked you a question about the model being set to Near Field and that is the only thing I question regarding your results as a possible difference in results.

Here is my model of the idea of a beam with and without a mast attached.

View attachment 12400

You didn't upset me at all, you posted while I was posting. I didn't even see your post until I had already given up, lol.

PS: your model is horizontal, I wouldn't expect much interaction although there will still be some current on the mast.
 
I just put the mast in the center of the boom, 97" I think is center. I'm on my phone now, but I probably should have looked at the assembly instructions for the boom-to-mast assembly point to be more accurate.

Well with Eznec I have to add a boom using two wires with the wire junction for these two wires where the mast attaches.

From the looks of your model the mast is not really attached to the antenna, it is just another element added very close and in front of the 1st director. Check how I did it on my horizontal model.
 
From the looks of your model the mast is not really attached to the antenna, it is just another element added very close and in front of the 1st director. Check how I did it on my horizontal model.
That is correct. I think grounded or isolated elements don't make a huge difference so I never even added the boom, but that could be my problem ......... if there is one.
 
That is correct. I think grounded or isolated elements don't make a huge difference so I never even added the boom, but that could be my problem ......... if there is one.

Do you think isolation of the mast is practical with a vertical beam setup?
 
Last edited:
Do you think isolation of the mast is practical with a vertical beam setup?

Not yet, I just finished plowing the driveway and getting a trailer of hay rolls. I'm gonna grab lunch and head to my room shortly. I didn't plan on 6" of snow last night or I'd have been done with hay already.
 
:oops: Alrighty then ...........

My being lazy and throwing a mast in there didn't work. CK didn't believe me and Marconi pushed me, so I did the work and went from 5 wires to 12 and now I think I have a true representation of what's going on. I owe y'all a thanks for that nudge.

M104_vert_mast_boom.jpg
 
Last edited:
  • Like
Reactions: 1 person
:oops: Alrighty then ...........

My being lazy and throwing a mast in there didn't work. CK didn't believe me and Marconi pushed me, so I did the work and went from 5 wires to 12 and now I think I have a true representation of what's going on. I owe y'all a thanks for that nudge.

View attachment 12419


Now THAT looks more believable! (y) No way I could believe the first plots based on my past experience.
 
Thanks for all the replies on this situation, I've not decided yet what to do, I'd love to mount the horizontal on the vertical boom, the problem is first the boom diameters are different, 3"&2". Second the mast is mounted in such a way that it can't be lowered, the tower is a hinged tower. The vertical antenna is a little less than 70#. And tilting the tower would be a huge job now, I have a TV antenna on the side and a 2 meter beam mounted on it. I'm thinking I may just put up a second tower, and hey it gives me more room for more antennas!!
 

dxChat
Help Users
  • No one is chatting at the moment.