Steve,
How does Hypower shorten that 160 meter antenna, with loading coils? Lou
----- Original Message -----
From: "Steve Forst" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Sunday, July 18, 2010 7:07 PM
Subject: Re: need some input on wire antennas for the Michigan House
> 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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