Hi everyone,
Though this hasn't been mentioned in the recent threads, I've found the no
counterpoise antenna and 20 foot crappie pole combo to work well. The
shorter version is 25 feet of zip cord (two conductor insulated wire) you
can split the two conductors apart from one end to the 12.5 foot point and
remove the 12.5 foot section of one conductor thus freed. The goal is to end
up with zip cord with a 25 foot conductor and a 12.5 foot conductor. I load
this quite successfully through a 4-1 balun into my IC-703+ It will work
from 6-20 meters and requires no counterpoise. If you don't want to split
the zip cord and remove half of one conductor, you can remove a few inches
of one of the conductors, creating the necessary 12.5 foot wire, just be
sure to make a gap big enough to ensure no coupling. You can make longer
versions to be able to load lower bands, the technique is the same, simply
remove 1/2 of one of the conductors and make it 50 feet, 100 feet, etc. My
plan is to make a 50-foot version as an inverted l so that I can try it on
40-meters and I'd really like to try a 100-foot version and see how it works
on 80. This is, as I understand it, another twist on the end-fed zepp.
You can buy these 20-foot fishing poles for less than $20, I got mine for
$12 and change. You could lash it vertically to the top of the motor home,
perhaps on the rail at the top of the ladder which is on the back of many
motor homes. That would get the top of the pole a good 30 feet off the
ground and make it easy to deploy the 25 or 50 foot version and the 100-foot
flat top would be within reach, as well.
73 all
Ron Miller
-----Original Message-----
From: For blind ham radio operators [mailto:[log in to unmask]]
On Behalf Of Tom Behler
Sent: Monday, July 02, 2012 10:23 PM
To: [log in to unmask]
Subject: Re: End Fed Zep Antenna
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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