Buck wrote:
Here is the URL to a home-brew 4:1 balun that should work from 160-10
meters. I am interested in a 6:1 balun.

Could you tell us why you are interested in a 6:1 balun?
--
73, Cecil http://www.qsl.net/w5dxp


----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==----
http://www.newsfeeds.com The #1 Newsgroup Service in the World! 100,000 Newsgroups
---= East/West-Coast Server Farms - Total Privacy via Encryption =---

On Sun, 30 Jan 2005 13:02:08 -0600, Cecil Moore
wrote:

Buck wrote:
Here is the URL to a home-brew 4:1 balun that should work from 160-10
meters. I am interested in a 6:1 balun.

Could you tell us why you are interested in a 6:1 balun?

Sure, thanks for the reply.


I have been looking at OCF dipoles and there are some that don't
appear to need a tuner when using a 6:1 balun. I have this dumb
obsession with learning about and working on multiband antennas that
don't need tuners.

I see some of the designs, and I would like to try them. Since the
4:1 is made from material in which I have an abundance, I would like
to know if I can make a 6:1 balun with the same stuff. While I am
thinking about that, if so, I would like to know if there is a rule of
thumb about making baluns like that so I can experiment with various
versions.

One OCF that I looked at showed an acceptable SWR on all bands between
30 and 6 meters with the exception of 17 meters. That's the kind of
thing I like to see and work with.


--
Buck
N4PGW

Buck wrote:
I have been looking at OCF dipoles and there are some that don't
appear to need a tuner when using a 6:1 balun.

I ran an OCF in college with a 6:1 air core balun from
Heathkit. It worked well but my transmitter had a
built in adjustable pi-net tuner. What are the dimensions
of the above OCF that you have described? Most OCF's that
I have modeled work just as well with a 4:1 balun as they
do with a 6:1 balun.

Jerry Sevick, W2FMI, describes a 6.25:1 balun in "Building
and Using Baluns and Ununs". It is a 1:1.56 UNUN followed
by a 1:4 BALUN.
--
73, Cecil http://www.qsl.net/w5dxp


----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==----
http://www.newsfeeds.com The #1 Newsgroup Service in the World! 100,000 Newsgroups
---= East/West-Coast Server Farms - Total Privacy via Encryption =---

On Sun, 30 Jan 2005 22:24:00 -0600, Cecil Moore
wrote:

Buck wrote:
I have been looking at OCF dipoles and there are some that don't
appear to need a tuner when using a 6:1 balun.

I ran an OCF in college with a 6:1 air core balun from
Heathkit. It worked well but my transmitter had a
built in adjustable pi-net tuner. What are the dimensions
of the above OCF that you have described? Most OCF's that
I have modeled work just as well with a 4:1 balun as they
do with a 6:1 balun.

Jerry Sevick, W2FMI, describes a 6.25:1 balun in "Building
and Using Baluns and Ununs". It is a 1:1.56 UNUN followed
by a 1:4 BALUN.


This is the antenna I want to copy before I start experimenting:
http://hamcall.net/6bandmegpole.html

I don't have a lot of information about baluns. What I have is mostly
related to Toroid baluns. I like the air coil idea in spite of the
size requirements. If additional turns or less turns change the balun
ratio, I would be interested to know as I can experiment and try
variations.

Thanks.


--
73 for now
Buck
N4PGW

Buck wrote:
This is the antenna I want to copy before I start experimenting:
http://hamcall.net/6bandmegpole.html

Hi Buck, they don't give exact building information as far
as I can tell. Here's what they say: Inverted V with the
center at 32 ft and ends at 8 ft. Approximately 135 ft
long fed with 100 ft of RG-213.

Why 32 ft with the ends at 8 ft? Because that is the
configuration that gives the advertised values of SWR.
Why 100 ft of RG-213? Because the losses in the coax
results in the advertised values of SWR. If you deviate
from their configuration including having different
ground conditions, you will, no doubt, need an antenna
tuner for some bands. They have probably fine tuned their
configuration so they can make their claims which you
probably will not be able to duplicate. I don't want to
discourage your experimentation - just make a prediction
based on experience.

If you really want an efficient all-eight-HF-band antenna
requiring no tuner, you can find one on my web page at
http://www.qsl.net/w5dxp/notuner.htm
If you don't want to go to the trouble of varying the
length of your feedline, you can at least learn what
you are up against in your quest.
--
73, Cecil http://www.qsl.net/w5dxp


----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==----
http://www.newsfeeds.com The #1 Newsgroup Service in the World! 100,000 Newsgroups
---= East/West-Coast Server Farms - Total Privacy via Encryption =---

On Mon, 31 Jan 2005 08:42:30 -0600, Cecil Moore
wrote:

Buck wrote:
This is the antenna I want to copy before I start experimenting:
http://hamcall.net/6bandmegpole.html

Hi Buck, they don't give exact building information as far
as I can tell. Here's what they say: Inverted V with the
center at 32 ft and ends at 8 ft. Approximately 135 ft
long fed with 100 ft of RG-213.

Why 32 ft with the ends at 8 ft? Because that is the
configuration that gives the advertised values of SWR.
Why 100 ft of RG-213? Because the losses in the coax
results in the advertised values of SWR. If you deviate
from their configuration including having different
ground conditions, you will, no doubt, need an antenna
tuner for some bands. They have probably fine tuned their
configuration so they can make their claims which you
probably will not be able to duplicate. I don't want to
discourage your experimentation - just make a prediction
based on experience.

If you really want an efficient all-eight-HF-band antenna
requiring no tuner, you can find one on my web page at
http://www.qsl.net/w5dxp/notuner.htm
If you don't want to go to the trouble of varying the
length of your feedline, you can at least learn what
you are up against in your quest.


thanks, Cecil.

I have looked at that before.

( Not to argue with you, but I considered your feedline switches a
form of tuner, just not conventional .

That is definitely a great looking antenna. I am glad you pointed out
the precision needed on the OCF I was looking at. What I am working
towards is a great all-band antenna that can be easily ported and
setup and used without switching (kind of like the T2FD) and no
unique parts required.

I am glad to meet you (and know who you are.) To be honest, I have
spent a lot of time on your site. At one time, I could have answered
many questions about your antenna without looking at it. Your site is
the first place I saw the ferrite beads on the feedline for a choke
and I have investigated them in depth since then too.

One thing I didn't find about the antenna was the bandwidth of 40/80
meters or an SWR chart for each band. (I realize that you might not be
able to do that easily, I'm just stating an observation.)

Also, in addition to the antenna I mentioned to you (It was only one
of several OCF's I am looking at), it seems to be common for OCF
antennas to use 6:1 baluns. Some do use 4:1 and most, regardless of
the balun, require a tuner.

I have several ideas that I am kicking around so being able to easily
be able to build an inexpensive balun at different ratios will come in
very handy for my experiments.

Before the internet there were books. The best one could hope for was
to see a picture of the author on the cover, but now, after all these
years, I am still amazed when I find myself in conversation what use
to be ... the untouchables.

It was great to meet you. Thanks for replying.

Buck.


--
73 for now
Buck
N4PGW

Buck wrote:
( Not to argue with you, but I considered your feedline switches a
form of tuner, just not conventional .

More precisely, a form of tuned feeders.

One thing I didn't find about the antenna was the bandwidth of 40/80
meters or an SWR chart for each band. (I realize that you might not be
able to do that easily, I'm just stating an observation.)

The HF bandwidth of that antenna *plus* the tuned feeders is 27
MHz, all the way from 3 to 30 MHz with an SWR of less than 2:1
(for the ham bands). I haven't measured the SWR outside of the
ham bands. There's a graphic that shows the SWR=2:1 bandwidth
for 40m to be about 160 kHz for a fixed length of ladder-line.
--
73, Cecil http://www.qsl.net/w5dxp


----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==----
http://www.newsfeeds.com The #1 Newsgroup Service in the World! 100,000 Newsgroups
---= East/West-Coast Server Farms - Total Privacy via Encryption =---