[TenTec] G5RV

Bwana Bob wb2vuf at gti.net
Sun Feb 1 16:01:30 EST 2009


There is one design that I saw that uses ladder line and no tuner. It 
uses a series of switches to switch in different lengths of 450 ohm line 
to achieve a good match to coax through a 1:1 choke balun. It's clever, 
but just as easy to use a tuner instead, in my opinion. Check it out at:
http://www.qsl.net/w5dxp/notuner.htm.

					73,

					Bob WB2VUF

Ken Brown wrote:
> Hi Al,
> 
>      You said:
> 
>> The advantage of a 
>> simple dipole, resonant length or not, fed  open line is a perfect 1:1 on 
>> any frequency on any band and you don't have to use coax anywhere.
>>   
> This may be true for a few particular frequencies, with each dipole 
> length/feed line impedance/feed line length combination you may try. And 
> you could modify the lengths to make it true on some different 
> frequencies. It is not true that there is a perfect 1:1 SWR "on any 
> frequency on any band" for one dipole wire length and one open wire feed 
> line length combination, even if you mean the SWR the transmitter sees 
> and not the SWR on the line itself.
> 
> With a matching network, it can be made to be nearly true, or at least 
> appear to the transmitter to be true, by adjusting the matching network 
> for each frequency, or perhaps bypassing it on those few special 
> frequencies where you don't need it. You'll probably be using coax 
> somewhere, like between the matching network and the transmitter, unless 
> your transmitter has a link coupled output to feed open wire feed line 
> directly.
>>> Huh? A perfect 1:1 what? Not SWR
>>>     
>> It wasn't clear but I meant a perfect 1:1 swr looking from the transmitter. 
>> Not on the line itself. The line has a high swr on some bands but the loss 
>> is minimal compared at any other type of feedline arrangement.
>>
>> AL 
>>
>>
>>   
> DE N6KB
> 
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