You might go look at the antennas that the guy at HY-Power antennas sells
they seem to be good for the money.
I don't have anything to with him except I have one for 40/80/160.
Charles F. Frost
Frosty K5LBU
frosty1@pdq.net
----- Original Message -----
From: "Dick Green WC1M" <wc1m73@gmail.com>
To: "'Mike Fatchett W0MU'" <w0mu@w0mu.com>; <towertalk@contesting.com>
Sent: Wednesday, April 20, 2011 4:35 PM
Subject: Re: [TowerTalk] Inverted V for 160/80 on the same feedline
> I've had good results on CW using a 80/160 trapped inverted vees made with
> a
> pair of Unadilla/Reyco traps.
>
> 73, Dick WC1M
>
> -----Original Message-----
> From: Mike Fatchett W0MU [mailto:w0mu@w0mu.com]
> Sent: Wednesday, April 20, 2011 2:26 PM
> To: towertalk@contesting.com
> Subject: Re: [TowerTalk] Inverted V for 160/80 on the same feedline
>
> In theory then you should be able to get a decent swr for both bands. I
> don't really care about the bandwidth too much as they will be used for
> CW in a contest.
>
> The goal is to have a good match and a single feedline for weight,time,
> baggage considerations for travel.
>
> W0MU
>
> On 4/20/2011 12:20 PM, Jim Brown wrote:
>> On 4/20/2011 10:53 AM, Mike Fatchett W0MU wrote:
>>> This might also be called a Fan dipole.
>>>
>>> Can you run 160 and 80 on the same feedline with decent swr? I have
>>> tried to model this and have not been very successful.
>>>
>> The short answer is yes, sort-of. In general, the longer antenna will
>> show the same SWR bandwdith as it would without the higher one, and the
>> higher one will have it's SWR bandwidth reduced by about half. My
>> experience is with 80/40 fans, and with 20/15/10 fans, and these
>> characteristics show up both in the NEC models and in measurements of
>> real antennas.
>>
>> This is exactly the opposite of what happens with the loaded multi-band
>> dipoles like those sold by Hy Power Antenna Company -- the higher band
>> antenna retains full SWR bandwidth, and the lower frequency (loaded)
>> band has reduced SWR bandwidth. I've also modeled those antennas, and
>> like them a lot. In boht cases, the reduced SWR bandwidth can be
>> compensated with a tuner and losses minimized by using low loss
>> feedlines.
>>
>> For more detail, see my applications notes on Antennas for Limited
>> Space. There are two that compliment each other -- one is text, the
>> other a power point presentation.
>>
>> http://audiosystemsgroup.com/publish.htm
>>
>> 73, Jim K9YC
>>
>> _______________________________________________
>>
>>
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