Tom,
I never used the Cobra. Perhaps one of the other Steve's on the list.
Over the past few years I've used 2 of the shortened dipoles from Hypower
Antenna Company in Pennsylvania. The current one up is full size for 80
and shortened for 160 with a total length of 164 feet. A 40 meter inverted
Vee is fed from the same feedpoint.
Also had a off center type up for a while, but it's unbalanced design gave
me RF problems causing the SS amp to trip on 80 and 40 meters at anything
over 400 watts.
As for the coax loss: Don't get too bent out of shape over it. Of course
the higher the freq and longer the run, the more it comes into play.
Another consideration for dipoles is the weight and visibility of the
larger coax.
I currently use Davis RF Bury-flex. Of course it's been several years and
I'm sure the price has gone up since I bought it.
73 and good luck with the move and new set up, Steve KW3A
----- Original Message -----
From: "tom behler" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Sunday, July 18, 2010 6:49 PM
Subject: need some input on wire antennas for the Michigan House
> Steve:
>
> Well, as usual, you are now causing me to think again on the coax issue.
>
> This is why this is such a great list.
>
> On a related topic, didn't you use one of those Cobra lites for a while?
>
> If so, what did you think of it?
>
> If you want to respond off list, use:
>
> [log in to unmask]
>
>
> 73 from Tom Behler: KB8TYJ
>
> ----- Original Message -----
> From: "Steve Forst"
> <[log in to unmask]>
>
> To:
> <[log in to unmask]>
>
> Sent: Sunday, July 18, 2010 2:43 PM
> Subject: Re: Need some input on HF wire antennas for the Michigan house
>
>
> Tom,
>
> Colin brings up an interesting point regarding loss, and only you can say
> if
> the loss is acceptable in your setup. Below is a link to a online coax
> loss
> calculator.
>
> Choose the type of coax from the drop down menu. Several name brands and
> generics are offered. enter your line length, freq. in mhz, load swr,
> and
> power output. Then let it calculate your losses.
>
> Don't forget that loss goes both ways: RX as well as TX. There is good
> stuff as well as junk stuff in all sizes. If you save a few bucks today
> buy
> buying poor quality coax and then have to replace it in 5 years, it wasn't
> much of a bargain.
>
> http://www.ocarc.ca/coax.htm
>
>
> 73, Steve KW3A
>
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