The point raised earlier about choosing an antenna rated one band below is apt.
I had a Butternut HF6V. On 40, 20 and 10, it was decent. On 80, I may as well
have put out a dummy load. Seriously.
I now have a CC MA8040v. Theres no possible comparison to a four square or a
dipole at height, or even to my 80m half-quad (think 80m inverted vee on 50
foot tower, shorted at the usual inverted vee feedpoint and fed at one end
against radials (and enclosed as a loop by a radial connecting both end) of my
youth), but at least the people I can hear can usually hear me.
That was often NOT the case with the Butternut termination resistor. Moreover,
I could hear far fewer stations.
(I didn't mention 15 above because it was only OK. On 15, only 1/4 wl on 15 is
active on the Butternut.)
On 40, I worked DX QRP with the B'nut. On 80, I was lucky to work ANYONE even
QRO.
73, Kelly ve4xt
Sent from my iPad
> On Oct 24, 2015, at 6:23 PM, Roger (K8RI) on TT <K8RI-on-TowerTalk@tm.net>
> wrote:
>
> From my experience with the AV640, I am impressed with it on 40 meters (Its
> lowest band) mounted at 25 and 32 feet with it matching the center
> fed,sloping half wave on average for DX. Due to its sensitivity to nearby
> objects I wouldn't recommend it as a limited space antenna. OTOH if that's
> the only space available, I'd use one. Get it as high as possible, or
> convenient. Tripod roof top mount, short pole or tower.
>
> I do have one caveat for both antennas. There are a lot of mechanical
> connections for jumpers, coils, traps and stubs subject to corrosion. I'm not
> down wind from any nearby industry, but I still get a lot of degradation of
> solder and Al to Al connections. The solder turns grey and just crumbles
> away. Al to Al held by screws often gets a buildup between the Al pieces. I
> have needed to redo a number of the coil and jumper connections on the AV640.
> I've had good luck with liquid Electrical tape. Around here the clear Krylon
> doesn't last long. YMMV
>
> As a comparison, All of my C3i antennas (one 7L 6-meter, two 12L 147, and two
> 11L 440s) have had all solder joints for the matching networks fail. What
> solder was left would crumble to powder when rubbed between my thumb and fore
> finger. Those all had several coats of clear Krylon. They are getting
> liquid electrical tape.
>
> 73
>
> Roger (K8RI)
>
>
>> On 10/24/2015 6:48 PM, Jim Brown wrote:
>>> On Sat,10/24/2015 6:49 AM, Daniel Danny Horvat wrote:
>>> There is no R6 antenna, there is a R-6000 antenna which I designed for
>>> Cushcraft followed by R8 antenna which was covered in K7LXC & N0AX report
>>> with high score.
>>
>> Congrats on your work, Danny. It's not easy getting good performance with
>> small size!
>>
>>> I was against implementing a 80m on R8 vertical back then (1998) due low
>>> efficiency and narrow bandwidth. MFJ has no problem to claim anything just
>>> to sell.
>>
>> N0AX acknowledged this in his write-up of their tests. Only a fool would
>> expect otherwise. :) His advice for all of these antennas as a class was to
>> buy one rated for at least one band lower than you intend to operate with
>> it. That is, if you want to work 40, buy one that will work 80, and don't
>> expect good performance on 80M from a 30 ft vertical.
>>
>>> Verticals, R5/R7 R6000 R8 and also clones AV620, AV640 are IMO better
>>
>> My friend K9OR, a very good op on a very small lot in Evanston (near
>> Chicago), has done very well with an AV640 on the roof of his small
>> ranch-style home.
>>
>>> than 43 foot verticals or even worse CHA250 and clone verticals.
>>
>> I suggest that anyone considering an HF vertical or other antennas for
>> limited space take a look at these pieces on my website.
>>
>> http://k9yc.com/VerticalHeight.pdf
>>
>> http://k9yc.com/43FtVertical.pdf
>>
>> http://k9yc.com/VertOrHorizontal-Slides.pdf
>>
>> 73, Jim K9YC
>> _______________________________________________
>>
>>
>>
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>
>
> --
>
> 73
>
> Roger (K8RI)
>
>
> ---
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