[Elecraft] Antenna Question

[Clay Autery]

On 10/10/2016 8:37 PM, Josh Fiden wrote:

> On 10/10/2016 5:39 PM, Clay Autery wrote:
>> All things being equal... IF you are using LMR-400 as the main feedline,
>> there is NO REASON to use a different diameter at the rotator...
> The point was using a lower loss cable for the long run up the tower,
> such as hardline, then flexible cable for the rotor/drip loop and
> short distance to the antenna feedpoint. At VHF, this is typical.

Right...  I'd use the best/lowest loss feedline I could afford/source,
too...  and then use a smaller jumper...  I was simply responding to the
OP who said he was using LMR 400.... and saying that LMR-400 CAN and IS
frequently used as that "jumper" for the rotator loop...  or something
similarly sized in the .4-.5 inch range....
>> Fail to see why an antenna failure or swap would require soldering "up
>> the tower"...
> Failure is not necessarily the antenna. It could be the solid center
> conductor fracture after being flexed too many times :)

THAT would be the result of improper design/installation
>
> If you swap antennas and it's a single run of cable, you have to
> manipulate the antenna on the tower to access the feedpoint. Then, for
> example, if you put up a longer boom yagi, the feedpoint will most
> likely be further away from the tower and your existing feedline won't
> reach.

Point taken....  I'm not a big part swapper/upgrader...  I build things
the best I can so I don't have to upgrade, so I didn't think of that... 
This situation would likely not occur for me, as I said above...  I
would likely NEVER use LMR-400 for a feedline run up a tower.  I'd use
the biggest/best feedline I could source/afford.

______________________
Clay Autery, KY5G
MONTAC Enterprises
(318) 518-1389