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Re: [TowerTalk] Fw: Multi-band dipoles

To: towertalk@contesting.com
Subject: Re: [TowerTalk] Fw: Multi-band dipoles
From: K8RI on TT <k8ri-on-towertalk@tm.net>
Date: Fri, 22 Apr 2011 16:05:25 -0400
List-post: <towertalk@contesting.com">mailto:towertalk@contesting.com>
On 4/22/2011 2:23 PM, Gene Fuller wrote:
> ----- Original Message -----
> From: "Gene Fuller"<w2lu@rochester.rr.com>
> To: "K8RI on TT"<k8ri-on-towertalk@tm.net>
> Sent: Friday, April 22, 2011 2:21 PM
> Subject: Re: [TowerTalk] Multi-band dipoles
>
>
>> Perhaps to the contrary Roger, The trapped antennas use somewhat less
>> lossy L's and C's whereas the BBD's are more likely using R's. A
>> horizontally deployed BBD might however be a little less noisey than a
>> vertical.

Wellll...perhaps, but I've always found the gain for trap verticals to 
be on the negative side and performance to be sadly lacking where I 
could run comparisons with dipoles in an A/B arrangement.
Multi band like the hy-tower, AV640 and Cushcraft version seem to work 
quite well. The AV640 (which I consider fragile) will beat the sloping 
half wave dipole at times and the dipole will beat it at times which is 
what I'd expect.
*Sometimes* the vertical is more noisy than the dipole and other times 
it's not. Oft times on 40 it cuts down on stateside QRM and QRN allowing 
me to hear the DX better.  I've only used 1/4 wave verticals on 40 and 
75 but have found that to be true with them as well.  Like other things, 
some times they do and some times they don't, while some are better than 
others. OTOH a lossy (the worst antenna) antenna can be wonderful 
compared to no antenna at all. <:-))

Many simple antennas get broad band by being lossy. Others use top hats, 
capacity hats on the ends  and other techniques to broaden the 
bandwidth.  Most of these do not lent themselves well to rapid and easy 
deployment.

Sure, you can find those who swear by the equivalent of a wet noodle and 
have even made DXCC (I hear tell), but I think their success was due to 
skill and/or perserversence in spite of the antenna they were using 
rather than because of the antenna's great capabilities.  I worked a guy 
in Central America who was testing his rig on the work bench with just a 
short wire laying on the bench and stuck in the coax connector (on 
6-meters)  I once worked Hawaii on 20 using the the copper pipe in the 
hot water heating system of my folks house.  I used to short out the 
coax from the rig to the hot water pipes when I'd shut down. I'd been 
listening on 20 and was shutting down due to an approaching storm. When 
I stuck the center pin on the pipe signals came up. <:-))  I can see the 
adds now and the possible (and unexpected) side effects of using the 
plumbing for antennas.

73

Roger (K8RI)

>> This thread is getting pretty thin.
>> Gene / W2LU
>> ----- Original Message -----
>> From: "K8RI on TT"<k8ri-on-towertalk@tm.net>
>> To:<towertalk@contesting.com>
>> Sent: Friday, April 22, 2011 1:26 PM
>> Subject: Re: [TowerTalk] Multi-band dipoles
>>
>>
>>> On 4/22/2011 12:39 PM, Jim Lux wrote:
>>>> On 4/22/11 9:18 AM, Bill Aycock wrote:
>>>>> Joe--
>>>>> You mention "actually tested" and "actually measured" in your post. Who
>>>>> did this, how was it done, and where is it published? I have never
>>>>> heard
>>>>> that these antennas were very good, and would like to hear any thing
>>>>> different.
>>>>> Bill--W4BSG
>>>> "good" can mean different things to different people.
>>>>
>>>> If you aren't concerned about efficiency (i.e. Tx Power vs Radiated
>>>> power) then these are a convenient solution to wideband operation,
>>>> installation in a variety of places, etc.
>>>>
>>> Probably not a great deal different than some trap verticals other than
>>> radiation angle?
>>>
>>> 73
>>>
>>> Roger (K8RI)
>>>
>>> _______________________________________________
>>>
>>>
>>>
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