hello all,
is there anybody who can give me detailt information about the
dimensions of a isotron-antenna for the 160m-band? any links or
homebrew-descriptions?
many tzhanks
Ron DG1HVW

Ron wrote:

hello all,
is there anybody who can give me detailt information about the
dimensions of a isotron-antenna for the 160m-band? any links or
homebrew-descriptions?
many tzhanks


Ohhhhhh Noooo!! The dreaded Isotron antenna!!!!!! If you are serious,
the Isotron is kind of like a dummy load on the end of a radiating
feedline. THe signal that is put out is due to the feedline.

If you are joking, Good one!!

- Mike KB3EIA -

Mike Coslo schrieb:

If you are joking, Good one!!

- Mike KB3EIA -
hello,
no joke. i am really interrested in, because i have build a very simple
eh-antenna(microvert) and i have done a few dx with this antenna abt. 3m
over the ground. (you can see it at www.ronald-winkler.de) a few weeks
ago i could not believe, that it is work. but it do. so i am looking for
other small simple antennas for the lowbands.
thank you.
ron DG1HVW

Yep, same principle, radiating feedline !
73, Arend

"Ron" wrote in message ...

Mike Coslo schrieb:

If you are joking, Good one!!

- Mike KB3EIA -
hello,
no joke. i am really interrested in, because i have build a very simple
eh-antenna(microvert) and i have done a few dx with this antenna abt. 3m
over the ground. (you can see it at www.ronald-winkler.de) a few weeks ago
i could not believe, that it is work. but it do. so i am looking for other
small simple antennas for the lowbands.
thank you.
ron DG1HVW

"Ron" wrote hello all,
is there anybody who can give me detailt information about the
dimensions of a isotron-antenna for the 160m-band? any links or
homebrew-descriptions?
============================
Ron, my guess is that none of the replies to your question are from people
who have ever used or have even seen the antenna.

With plenty of idle time to spare they are just repeating old wives' rumours
for a little mischievous amusement.

From its construction I estimate its performance to be marginally worse
than a magloop of the same physical size and operating frequency. And
magloops don't do too badly, do they?
---
Reg

Ron wrote in message ...
hello all,
is there anybody who can give me detailt information about the
dimensions of a isotron-antenna for the 160m-band? any links or
homebrew-descriptions?
many tzhanks
Ron DG1HVW


Try dxzone antenna homebrew pages...

http://www.dxzone.com/catalog/Techni...ence/Antennas/

there is also a section on 160 mt antennas

http://www.dxzone.com/catalog/Techni...Antennas/160M/

73
iw5edi simone

Max schrieb:


Try dxzone antenna homebrew pages...

http://www.dxzone.com/catalog/Techni...ence/Antennas/

there is also a section on 160 mt antennas

http://www.dxzone.com/catalog/Techni...Antennas/160M/

73
iw5edi simone

thank you very much. thats what i want.
Ron

Reg Edwards wrote:
"Ron" wrote hello all,

is there anybody who can give me detailt information about the
dimensions of a isotron-antenna for the 160m-band? any links or
homebrew-descriptions?

============================
Ron, my guess is that none of the replies to your question are from people
who have ever used or have even seen the antenna.

Not used, but I have seen them. Arguably the most attractive antenna out
there. i hop

With plenty of idle time to spare they are just repeating old wives' rumours
for a little mischievous amusement.

I've read a fairly in depth report on one of the EH antennas. They said
it worked. And the feedline radiation seemed to be what made it work. I
haven't used a backpacker, but their work looked good enough to give it
some credibility.

What do you think about the information that they publish

http://www.rayfield.net/isotron/isohow.htm

Claiming the transmit performance is the same as a half wave dipole, and
the noise on receive is 3 db down from a half wave dipole? This would
seem to indicate that the Isotron is a *superior* antenna as compared to
a dipole. They don't mention anything about radiating feedline. So okay,
maybe the feedline doesn't radiate.

Its *hard* to imagine why anyone would use anything else!


From its construction I estimate its performance to be marginally worse
than a magloop of the same physical size and operating frequency. And
magloops don't do too badly, do they?


- Mike KB3EIA -

Reg Edwards wrote:
"Ron" wrote hello all,

is there anybody who can give me detailt information about the
dimensions of a isotron-antenna for the 160m-band? any links or
homebrew-descriptions?

============================
Ron, my guess is that none of the replies to your question are from people
who have ever used or have even seen the antenna.

Not used, but I have seen them. Arguably the most attractive antenna out
there. i hop

With plenty of idle time to spare they are just repeating old wives'
rumours
for a little mischievous amusement.

I've read a fairly in depth report on one of the EH antennas. They said

it worked. And the feedline radiation seemed to be what made it work. I
haven't used a backpacker, but their work looked good enough to give it
some credibility.

What do you think about the information that they publish

http://www.rayfield.net/isotron/isohow.htm

Claiming the transmit performance is the same as a half wave dipole, and
the noise on receive is 3 db down from a half wave dipole? This would
seem to indicate that the Isotron is a *superior* antenna as compared to
a dipole. They don't mention anything about radiating feedline. So okay,
maybe the feedline doesn't radiate.

Its *hard* to imagine why anyone would use anything else!


From its construction I estimate its performance to be marginally worse
than a magloop of the same physical size and operating frequency. And
magloops don't do too badly, do they?


- Mike KB3EIA -


The isotron design is low efficiency, approximately 2-15%, depending on the
frequency/model you have. Efficency isn't everything though in real antenna
systems:
It approximates a point source in a highly multipathed environment. Therefore
there are positions of placement/times where the antenna is in a gain-volume
(as opposed to a null-volume) from the multipath. Ergo it will have a
measureable dBm approximating a dipole in the far field. This is a transient
effect and depends on ground; environment; and height.

However, there are times where an isotron can be placed quite high, whereas the
phase center of a dipole cannot (because the dipole is much bigger; bulkier;
unsightly.) Then the enhancement over higher ground can give a seeming
approximate equality or advantage over the much lower dipole.

In true free space, the isotron is a mediocre/poor antenna, in my opinion. In
real environments, it does have a useful niche, especially if you do 30, 40, or
80 M and can get it 50 or more feet up. There are reports of folks who put
isotrons on top of apartment buildings and really kick butt. I doubt they win
contests, but I'm sure they have a good time!

I have never seen anything deceptive in isotron's ads.

73,
Chip N1IR