There are some who say no way you want ladder line in the shack, others say
bring it all the way to the tuner if possible. I've never brought it all the
way to the tuner but with the cobra ultralite I did bring about 5 feet of
ladder line in when that was up and then connect a balun and coax around to
the radio, mainly because it has to run along base board heating and I
didn't think the ladder line would agree with that, but I never had a
problem with RFI and I ran the amp there too, I never had any problem,if
anything that was the one time I had the least RFI even with computer
speakers or anything. Maybe if I ran the rest of the way around I might
have, I don't know but given the option I'd do it again. I ran that through
a window in fact, shut the window on it and it never complained. I find a
lot of that stuff depends more on your setup, what works for one person at
one qth may not work at another. I find every time I move I have to do
things a little different from sometimes having to do everything I can to
prevent RFI to my last 2 QTH's doing absolutely nothing, not even an RF
ground and not having any problem. This is the first place I even could run
an RF ground if I even wanted to but I'm almost afraid to mess with what
works so as long as I have the lightning ground outside which I do, I may
not bother. It's just another thing to cause an issue, if it's not broke I'm
not going to fix it.
----- Original Message -----
From: "Colin McDonald" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Friday, November 02, 2012 4:51 PM
Subject: Re: Re_ladder line missmatch and quick deploy 40/10M portable
antenna
> is it ladder line, twin lead, or window line?
> Window line, which is basically the insulated version of ladder line, will
> be 450 ohms, though apparently it does come in 300 ohm versions, which is
> smaller, narrower in width, than the 450 ohm stuff.
> Twin lead is flat cable without the open spaces and will be 300 ohm.
> I suspect a 4 to 1 balun will deal equally as well with whatever kind of
> line you have.
> I like the idea of a short run of coax out of the shack connected to the
> ladder line through a 4 to 1 balun. Less RFI and less swr and tuning
> issues
> that way.
> Of course, this can all be argued endlessly lol.
> If you can get the ladder/window/twin lead to the tuner, go for it, but if
> not, just use the coax with or without a 4 to 1 balun...the tuner will
> take
> care of it either way.
>
> 73
> Colin, V A6BKX
> ----- Original Message -----
> From: "Michael Ryan" <[log in to unmask]>
> To: <[log in to unmask]>
> Sent: Friday, November 02, 2012 11:51 AM
> Subject: Re_ladder line missmatch and quick deploy 40/10M portable antenna
>
>
>> Hi John and all:=20
>>
>> The ladder line in question came from a commercial type G5RV sold at =
>> Radio World in Toronto. It lists the line as 300 ohm. This line also has
>> =
>> a transformer attached to it with 50 feet of coax.=20
>> Now, to my next post: I'm researching an antenna solution for my =
>> apartment. I'm only a casual op, where my 102 station is currently set =
>> up at my parents QTH and I'd like to move it into my spare bedroom of my
>> =
>> apartment.=20
>> I'd like a quick deploy 40 to 10M antenna. something that I could place =
>> out side my window and temporarily run my coax in and when finished, =
>> simply take it down and put it away until next time.=20
>> Of course, it would be a bit of a pain to put up and take down each time
>> =
>> I'd want to operate but that's life in an apartment. An antenna that =
>> doesn't require constant fiddling with alligator clips and coils for =
>> operating on each band but I suppose I could have a switch box built to =
>> handle that.=20
>> Our club uses a Hy-gain vertical which one of the members did this kind =
>> of mod. I'm checking into the model # but don't think Hy-gain makes this
>> =
>> antenna any more. the house! LOL=20
>>
>> 73:=20
>>
>> Michael De VO1AX=20
>
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