All that is nice, but like all things, that estimate may be flawed.
1. Some guys have a 400 ft plus run to the tower (me)...over 1 db loss
plus another 200 feet to the top. Over .5dB. That makes over 1.5 dB
2. Some guys use the run to the tower for 10 meters as well as VHF with a
box at the tower.
3. If you already own the hardline shipping it is not as expensive as you
might think, at least compared to going out and buying all new 1/2 and then
paying for that shipping too. I used to have access to loads of 1 5/8 and
shipped it all over the US.
4. Connectors are expensive. You buy them used, or make your own for
less than five bucks. Many times they are included if you buy the 1 5/8 used.
Adapters can be obtained used or new at most hamfests for around $5.
5. Most guys get their 1 5/8 used. I got some for free and shopped
around for others. I once obtained several excellent 2000+ foot spools of
used
in the early 2000s for 50 cents a foot.
6. Almost all have jumpers. The cost of the jumper is minimal. Maybe
$10 for PL259s and a few feet of LMR400.
7. I once needed four runs of coax for direct burial for my four 2
element quads suspended on ropes around the yard. I had tons of the 1 5/8
laying
around, so I used that for my 200 foot runs. It had nothing to do with
ego, running high power and certainly was not about being low loss compared
to 1/2 inch. It was what I had and I got most of that for free.
You'll find many guys like me who are contesters, who don't have an endless
supply of cash and scrounge up the hardline and connectors for pennies on
a dollar. Not many go out and spend $14/ft for hardline.
Bill K4XS
In a message dated 5/31/2013 5:19:50 A.M. Coordinated Universal Time,
w3ab@yahoo.com writes:
I have been watching this discussion with a lot of interest. The interest
being, what is the power loss at 30 MHz for a 100' run of 1/2" vs 1 5/8"
hardline? Turns out it is ~82 W.
This is for LDFX-50A
1 5/8" loss @ 30 MHz/100' = 0.109 dB
1/2" loss @ 30 MHz/100' = 0.375 dB
http://www.rfparts.com/coax/heliaxcoax.html?cat=469
That will not break any pile-up on any band. Period!
Everything from hereon in is based on a 100' run of coax. You can do the
math for any run shorter or longer.
Now, what is the cost of shipping 100' of 1 5/8" coax from the east coast
to CO? Ain't gonna be cheap.
How much do the connectors cost? Ain't gonna be cheap.
Need any adapters? Not cheap.
How manageable is the big stiff stuff? It's big, stiff and heavy.
What about the 1/2" stuff. Easy. The ultraflex is even easier to manage.
Gotta put flexible jumpers twixt the run and rotated antenna as well as in
the shack in both cases.
1/2" hardline costs ~$3.00/ft vs ~$14.00/ft for the 1 5/8" stuff.
Geez, unless you are running more than 6 kW @ 30 MHz (1/2" hardline) with
a
100% duty cycle, I can see no reason for the use of 1 5/8" hardline. The
last time I checked the legal limit for us, USA hams, was 1.5 kW PEP.
Unless you NEED bragging rights. Then, by all means go for it.
IMHO, sell the 1 5/8" where it resides and buy new 1/2" at your new new
QTH.
BTW, all my shack jumpers used to be LMR-400 but I got tired of the lack
of flexibility so I went with to LMR-250UF.
Of course your mileage may, and will vary.
---
Ciao baby, catch you on the flip side.
GEO
http://www.w3ab.org
3 thoughts:
Recall that the gain from a lot of aluminum high in the sky works both
ways. QRO works one way only.
If you are unable to hear them, you will NOT work them.
I'd rather put 12 dB of gain @ 60' rather than get 12 dB of gain from the
220 VAC outlet.
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