Steve:
I have an Alpha Delta DXCC here at the house. It's for 40 through 10
meters, although it does cover 80 meters if you work at it. So, I am very
familiar with that line of antennas.
The Alpha Delta DXCC is 82 feet long, and I had considered one for the RV.
But again, my problem is a lack of nearby trees in the right locations.
This is why I was thinking of something that would be "end fed", in that I
could maybe get away with needing fewer supports.
I'll keep at it here.
73 from Tom Behler: KB8TYJ
----- Original Message -----
From: "Steve" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Monday, July 02, 2012 4:06 PM
Subject: Re: End Fed Zep Antenna
> Tom,
>
> Why don't you look at one of the antennas from Alpha-Delta? They have a
> 40-10 meter dipole that is 40 feet in length, and a DXDD for I think
> 160-10
> that is 82 feet long. They are a bit pricey but well-constructed.
>
>
> ----- Original Message -----
> From: Tom Behler
> To: [log in to unmask]
> Sent: Sunday, July 01, 2012 10:23 PM
> Subject: Re: End Fed Zep Antenna
>
>
> Mike:
>
> I actually have a 102-foot G5RV, just sitting here doing nothing, but my
> concerns in using it are as follows:
>
> 1. I don't have 102 feet of space to work with, and
>
> 2. I don't think I could get it high enough to work well, especially on
> 40
> meters.
>
> If you have other suggestions for easy-to-deploy wire antennas, feel free
> to
> send them my way.
>
> I'm looking for something to cover 40 through 10, and 80 through 10 if at
> all possible, although I realize that is a very tall order.
>
> 73 from Tom Behler: KB8TYJ
>
> ----- Original Message -----
> From: "Mike Duke, K5XU" <[log in to unmask]>
> To: <[log in to unmask]>
> Sent: Sunday, July 01, 2012 10:16 PM
> Subject: Re: End Fed Zep Antenna
>
>
>> Tom,
>>
>> I ran one on 80 meters for several years.
>>
>> They work, but the internal automatic tuners are not likely to be able
>> to handle them.
>> For those who do not know what this antenna is, it is a half wave
>> length of wire at the lowest frequency you wish to work. As the name
>> implies, it is fed at one end by connecting one side of a piece of
>> open wire line or more likely now days, 450 ohm window line to the end
>> of the half wave length of wire. The other wire in the window line is
>> left un-terminated at the antenna end, but connected to the ground
>> terminal, or to the other side of the balun of the antenna tuner. This
>> un-used conductor basically works much like a counterpoise, and thus
>> becomes more or less the second half of the antenna.
>>
>> The advantages of the end fed Zep are that it will tune on several
>> bands above the design frequency. Also because it is end fed, it is
>> often much easier to keep all or most of it hidden from the antenna
>> police.
>>
>> One disadvantage is that it tends to be a little less efficient than a
>> center fed, although it certainly works well enough if you can get it
>> tuned.
>>
>> The biggest disadvantage, however, is that matching the end fed zep is
>> very tricky.
>>
>> The matching problem occurs because the antenna is fed at the end of a
>> half wave. This means the impedance is extremely high. Also, because
>> it is fed at a high rf voltage point, rather than at the high current
>> point in the center, not all tuners will handle the high voltage, even
>> at the 100 watt power level.
>>
>> The one I ran was cut for 80 meters. It would tune fine on 40, 20, and
>> parts of 10 meters, but not well anywhere else.
>>
>> There are some end fed zeps on the market that have a matching network
>> for one specific band, and that match the antenna directly to coax.
>> There is also at least one out there that claims to work on 40, 20,
>> and 10 meters.
>>
>> We were trying to use that multi band model for our GOTA station at
>> field day last weekend. However, when we changed to a G5RV Junior, it
>> blew the end fed right off the planet on both 40 and 20 meters.
>>
>>
>>
>> ----- Original Message -----
>> From: "Tom Behler" <[log in to unmask]>
>> To: <[log in to unmask]>
>> Sent: Sunday, July 01, 2012 4:18 PM
>> Subject: End Fed Zep Antenna
>>
>>
>> Hi, all.
>>
>> As many of you know, I have been struggling with the Predator
>> screw-driver
>> antenna on my 31-foot Holiday Rambler RV, ever since my N2VZ
>> Turbo-tuner
>> became non-functional back about a year ago.
>>
>> The Turbo-tuner issue is another story for another day, but suffice it
>> to
>> say that, due to the fact that N2VZ won't honor is "Lifetime
>> Warranty", it
>> is now not a viable option for me.
>>
>> Anyway, in the interest of moving on, and pursuing other
>> possibilities, I am
>> wondering if something like an end-fed zep antenna might be an
>> easily-deployable HF antenna for the RV. There is not much room in
>> our RV
>> spot for a traditional half-wave dipole, or even an antenna like the
>> Alpha
>> Delta DXCC, but I thought an end-fed zep might be fun to try.
>>
>> Does anyone have experience with these?
>>
>> How much wire would I need to get up and running, say on 40 through
>> 10
>> meters?
>>
>> How easy or dificult would it be to make one?
>>
>> I think I could run the antenna from the RV to a tree on the other end
>> of
>> our RV lot, if that would help.
>>
>> Just exploring options here.
>>
>> With the North American QSO Party CW contest coming up in early
>> August, I'd
>> like to have something up and running from the RV by that time, even
>> if it
>> is temporary.
>>
>> 73 from Tom Behler: KB8TYJ
>>
>
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