On 2/22/98 20:22, Mark van Wijk at mark3fcd@xs4all.nl wrote:
>
>Setup of new Vertical R7000+80
>
>1. Search for 10 feet mast.
>
>Checked five(!) construction locations but no one wanted to sell a piece.
For my R7000, I used a 1.5" heavy galvanized water pipe. It actually
isn't quite big enough, and a 2" OD mast would be better, but it was
inexpensive to find.
>5. The nut on one of the R7000 clamper-to-mast is stuck !!
>Can you believe it? It's at the middle of the bolt and won't move. Finally
>it breaks under serious force. Now wait untill the shops open... And surely
>this is English type of measurement so I have to do some rework to make our
>clamper fit.
The hardware is stainless steel and will have a tendency to gall when
turned under stress. I had a similar problem with my hardware and saved
the day by applying lots of silicone spray lubricant to the threads
before removing the nuts.
>6. I'm a big guy so I can put up that vertical all by myself huh?
>Well it almost totally crashed ...
I don't have the 80 meter kit for my R7000, but I found could upright it
at the bottom of the mast, put the clamp hardware on loosely, then slide
the whole kit 'n kaboodle up the mast. Pulling out one of the radial
wires helps to make room for this operation.
The R7000+80 is considerably taller, so this may be more difficult.
>8. 10 is ok, 15 is reasonable (dips at 21080), 20 is ok, 40 is BAD (SWR
>1:3-4 in CW section, minimum at 7070), 80 is BAD (SWR1:4 in CW and min at
>3600).
>Ok, despite the correct preadjustment there is clearly some fine tuning
>needed which is normal. So am I going to take this 45 ft thingy down to
>readjust? No thank you. Not today I guess, cause my bones are hurting enough
>yet.
I took mine down 4 times doing adjustments. They really don't change very
much. I don't think you'll see 1:1 SWR with this beast on every band. But
it should be under 2:1 on each band. One reason I did not get the 80m kit
is that it reduces the SWR bandwidth on 40m, and the 80m SWR bandwidth is
very narrow.
Frankly, if I had a rig with an automatic antenna tuner, I wouldn't worry
about the SWR that much. but it almost sounds like you may have a problem
with the 20m trap.
So, how do you like your R7000+80?
Bill Coleman, AA4LR, PP-ASEL Mail: aa4lr@radio.org
Quote: "Not within a thousand years will man ever fly!"
-- Wilbur Wright, 1901
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