It is worth taking a look at the Swiss quad described in the Rothammel Antenna
Book, which as far as I can tell was never for sale in English. The Swiss quad
takes the idea of the HB9CV yagi and applies it to a quad to achieve over 30 db
F/B with a lambda/8 boom. I have personally used a few of the HB9CV yagis and
was amazed by their F/B.
The German version of the Rothammel book is available for free online.
Rudy N2WQ
Sent using a tiny keyboard. Please excuse brevity, typos, or inappropriate
autocorrect.
> On Sep 1, 2016, at 3:23 AM, Martin Sole <hs0zed@gmail.com> wrote:
>
> I've long been a quad aficionado and have generally devoured any information
> I can find on them. The double driven W6PU quad is an example of something a
> little different that suggests it can still be a useful antenna. I still have
> a lightning bolt quad along with lots of extra parts and hope to shortly
> rework it as a 3 element with 30 and 40 added to the other 5 bands together
> with moving the10 and 12m elements to improve on their compromise positions.
> We'll see.
>
> But in all of this the information by Cebik probably stands out as the most
> thorough examination of the quad and it's comparison with the yagi array. My
> take away from his work is whilst the quad might well demonstrate some gain
> advantages in some situations it suffers from 2 seemingly intractable issues.
> Firstly the gain, F:B and SWR responses are somewhat more "peaky" than the
> equivalent yagi curves. Secondly that these responses are less well aligned.
> That great 30dB F:B at the CW end of the band matches to an unfortunate 6 dB
> drop in peak gain whilst up in the SSB end of the band the extra bit of gain
> is matched to a meagre F:B.
>
> I do think that the closed loop antenna tends to be lower noise, there seems
> to be a lot of anecdotal information that makes this hard to ignore and my
> own experience points to much the same. In SE Asia we do get lots of heavy
> monsoon rain and there seems little doubt the quad works better at those
> times.
>
> I definitely would agree that like the newer dynamic antennas the quad really
> needs either a telescopic tower or one with a fast and convenient raising
> fixture. The frailty of both these antenna types on a fixed 80 foot plus
> tower is never going to be ideal.
>
> Martin, HS0ZED
>
>
>
>> On 31/08/2016 20:44, Joe Giacobello, K2XX via TowerTalk wrote:
>> Ed, I have been using quads since the late 70s. My first one was a Skylane
>> tri-bander, which used low strength, flimsy spreaders compared to what's
>> available today. I've also had a couple of six band quads with four
>> elements on 10-20M and seven on 6M with a 24 foot boom. They do indeed work
>> well and, when multibanded, are far less of a compromise than multiband
>> Yagis. A 2 element quad has only about 0.3 dB less gain than a three
>> element monoband Yagi. Going to multielement quads beyond three elements is
>> an exercise in rapidly diminishing returns. The gain increase is relatively
>> small given the increase in expense, complexity and vulnerability. Four
>> element Yagis and beyond are then a better investment.
>>
>> I am currently using a two element duobander on 30 and 40M on a 20 foot
>> boom. It's almost equivalent to a three element monoband Yagi but on a far
>> shorter boom. Cubex's 26 foot spreaders have held up well at this windy
>> QTH, although the combination of ice and wind can be destructive.
>>
>> 73, Joe
>> K2XX
>>
>>> Ed Sawyer <mailto:sawyered@earthlink.net>
>>> Wednesday, August 31, 2016 9:16 AM
>>> The Quad vs Yagi debate is timeless. I always thought there were a number
>>> of things contributing to it:
>>>
>>> - Back in the day before computer optimized gain yagis, the quad
>>> was a simpler way to get more gain on a given boom. The full loop started
>>> it off with something like 1.3dB gain over the dipole element and placing
>>> evenly spaced elements gave good results for a 2 or 3 el quad.
>>>
>>> - The average height of a quad (I have to believe) is the center
>>> point between the top wire and the bottom wire (or diamond tips) so the HFTA
>>> analysis should be the same for a yagi vs a quad at a given height when
>>> horizontal polarization is used.
>>>
>>> - However for the early years, low "towers" of 30 ft or so, if they
>>> were fed for vertical polarization and happen to be in a good to excellent
>>> ground conductivity area, the take off angle was likely better for long
>>> "band opening" DX and impressed their owners.
>>>
>>>
>>>
>>> Today, there is much better ability to get maximum gain out of a longer boom
>>> yagi that is way easier to install and maintain and we understand the take
>>> off angles much better.
>>>
>>>
>>>
>>> I could be wrong on the above folklore, but that's my guess.
>>>
>>>
>>>
>>> Ed N1UR
>>>
>>> _______________________________________________
>>>
>>>
>>>
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