[TowerTalk] If you had a choice

[Jim Lux]

On 10/16/12 4:37 PM, EZ Rhino wrote:
> No doubt about it!  This is not a small undertaking.  I'd consider pre-ordering the book if it would help, and I bet a lot of others would pre order too.  What else can I do to help?  If they were ready to test tomorrow, I'd have my antenna of choice send to them to use for the test, then they can ship it back to me when done so I can put it on the tower, but I don't think they are quite ready yet. :-)
>
> If it were possible to get a hold of all antennas at the same time, I think a good way to do this would be to do it the week of field day with one of these bigger clubs that puts up several towers for their op.  The test antennas could be on portable towers in a big field, all pointed the same way.  Close range and further range testing could be done at the same time (ie east coast or even EU).  While we're dreaming here, maybe I can plan a money tree....
>
> Chris
> KF7P
>
>

These kinds of tests are a big undertaking, and MUCH more than a day's 
or weekend's work.

I think if I were doing it, I'd rent a crane or boom truck and fabricate 
some sort of pivoting mounting bracket on top, so I could lay the boom 
over, put the antenna on it, tilt the boom up, flatten the antenna, and 
then rotate it to get your pattern cuts.

This is basically what you have on an antenna range (along with 
precision sources and equipment).  It makes it pretty fast to put an 
antenna on, zip it up high, etc., and bring it back down.

But then you have the work of assembling all those antennas on the 
ground (which could be done over a period of weeks if you have somewhere 
to store them).

I can't recall what we charge to use the Mesa antenna range at JPL, but 
I think it's in the 500-1000/day ballpark.  That gets you positioners, 
towers, sources on the other side of a valley a mile away, etc.  I 
imagine it's competitive with other ranges.  The reason I mention this 
is that by the time you rent a boom truck, etc, you're probably up in 
the price range where it might be worth it to find a real range to use.

The way to get it cheaper is to find a professor to get a student to do 
the project as part of a senior project or master's thesis, and then you 
can apply for some grant money to fund it.

I'd say you'd be doing well to do an average of an antenna a day 
(assemble, measure, disassemble).  You might be able to overlap.


So, if you're looking for kickstarter type funding... you will be paying 
the people working on it and for facilities, etc.

Figure something like a work month for a senior engineer, a work month 
for a technician, and a couple week's range time. In round numbers, 
about $50k.


Obviously, if you've got good scroungers, equipment to borrow, and 
people to help for free, you can do it for less.  But the whole 
logistics thing means it takes careful planning.. Running multiple 
antennas up and down multiple times is pretty time consuming.