Hi Lou,
Yeah, it has a pair of loading coils. The coil design is similar to the
Alpha Delta's, and the old W9INN antennas, with some enameled wire close
wound on a pvc form.
The first one I had was 160, 75, and 40 at 124 feet long and I worked lot's
of Stateside and a fair amount of DX with 100 watts on 160.
73, Steve KW3A
----- Original Message -----
From: "Lou Kolb" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Sunday, July 18, 2010 7:34 PM
Subject: Re: need some input on wire antennas for the Michigan House
> 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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