Scanner Antennas available
 

I wouldn't normally advertise here, but I seen a post or two in recent times
looking for an antenna.

Have 2 types available. A Discone and a Ground Plane. Both good for 25 -
1000 MHz. Both have a 1 year Factory Warranty. Both have a UHF Female
Connector, the latter model having an 18" lead.
The discone is an Antenna Specialist MON 64, the Ground Plane is a MONR-31

Should you wish more information, please feel free to write to


Thanks,

CL

CL schrieb:

Have 2 types available. A Discone and a Ground Plane. Both good for 25 -
1000 MHz.

On technical reason a ground plane antenna can NEVER work as a broadband
antenna. It is limited to some frequencies or relatively small frequency
ranges with acceptable gain.

A discone has some gain above 0dBi on the wohle specified range up to 2
dBi. A groundplane has some gain up to 3 or 4 dBi on resonant
frequencies and dramatic loss down to -(!)15dBi on nonresonant ranges.

odo

I'm not saying I "disagree" - though I've never fully gotten into the design
basics/performance, but "I" didn't "design" them - I only sell them! The
last customer who bought a discone from me was very pleased with it - for
whatever that is worth. I have the previous version of the ground plane I
now handle, it didn't cover past 400 MHz, but it seemed to work well. I was
just answering a need of sorts. Trying to be helpful. CL

"Volker Tonn" wrote in message
...


CL schrieb:

Have 2 types available. A Discone and a Ground Plane. Both good for 25 -
1000 MHz.

On technical reason a ground plane antenna can NEVER work as a broadband
antenna. It is limited to some frequencies or relatively small frequency
ranges with acceptable gain.

A discone has some gain above 0dBi on the wohle specified range up to 2
dBi. A groundplane has some gain up to 3 or 4 dBi on resonant
frequencies and dramatic loss down to -(!)15dBi on nonresonant ranges.

odo

CL schrieb:

I'm not saying I "disagree" - though I've never fully gotten into the design
basics/performance, but "I" didn't "design" them - I only sell them!

Bad enough that you believe in the sheet (=****) of the manufacturer. A
professional seller you should know the technical basics on the products
he sells.
Never(!) believe in the "specs" a manufacturer gives, without some
verification of plausibility on it. Name these "broadband groundplane"
antennas JUNK and send them back to the manufacturer. Or keep them on
1/20 of the price and sell them as 'groundplane with gain some*where*
between 25 and 1300Mhz' at 1/10 of the original price. This should
satisfy everybody but the manufacturer :-)

regards,
Volker

Eh, I did say I had tried a "previous" version of the ground plane. It did
"seem" to work ok. At that time, I didn't have 1/4 of the equipment I now
have. I've not really had time or space to prove anything in or out. I'm
preparing to move to a new location, then I can play all I want. More room
for antennas and so on. Here, there hasn't been room for much of anything.
No, I do "not" agree with all they write. There is always room for
disagreement. I suppose it comes down to the point of IF that is the only
product out there, and you need it, what choice do you have ESPECIALLY if
you're not capable of building antennas like some of us are? Not much of a
choice from that perspective. It's up to the individual. I'm not "pushing"
anything. If they want to buy - they will, if not - so be it! That is their
choice. CL.

"Volker Tonn" wrote in message
...


CL schrieb:

I'm not saying I "disagree" - though I've never fully gotten into the
design
basics/performance, but "I" didn't "design" them - I only sell them!

Bad enough that you believe in the sheet (=****) of the manufacturer. A
professional seller you should know the technical basics on the products
he sells.
Never(!) believe in the "specs" a manufacturer gives, without some
verification of plausibility on it. Name these "broadband groundplane"
antennas JUNK and send them back to the manufacturer. Or keep them on
1/20 of the price and sell them as 'groundplane with gain some*where*
between 25 and 1300Mhz' at 1/10 of the original price. This should
satisfy everybody but the manufacturer :-)

regards,
Volker

CL schrieb:

Eh, I did say I had tried a "previous" version of the ground plane. It did
"seem" to work ok. At that time, I didn't have 1/4 of the equipment I now
have.

Your initial posting implied (to me) that you are a professional seller
of this antennas (and maybe other equipment).
Sorry when I was wrong. As a "normal user" you may have trusted the
manufacturers "promises".

regards,
Volker

I DO handle equipment (seller) but though I may tend to agree with you in
your point, if that equipment is the only game in town and someone is in
need, what are they going to have a choice of? Some antennas do work better
than others. That is a given. I've just not had space to experiment on my
own to find out for my self - their claims. Very little room here for
antennas and most of my area is all aluminum siding, high voltage lines and
no way to go above it or away from it. "I" am not "pushing" any particular
product. I merely mentioned I have them. I did say a previous customer had
good results with the discone model. So, that is as far as I'm going. As I
said, if someone wants to buy - ok, if not, that is ok too. I'm a bit more
educated than the average RS sales person, but I am NOT going to get into a
war of technicalities over designs "I" had nothing to do with. I don't have
time for that. CL

"Volker Tonn" wrote in message
...


CL schrieb:

Eh, I did say I had tried a "previous" version of the ground plane. It
did
"seem" to work ok. At that time, I didn't have 1/4 of the equipment I
now
have.

Your initial posting implied (to me) that you are a professional seller
of this antennas (and maybe other equipment).
Sorry when I was wrong. As a "normal user" you may have trusted the
manufacturers "promises".

regards,
Volker

"Volker Tonn" wrote:

On technical reason a ground plane
antenna can NEVER work as a broadband
antenna. It is limited to some frequencies
or relatively small frequency ranges with
acceptable gain.

A discone has some gain above 0dBi on
the wohle specified range up to 2 dBi. A
groundplane has some gain up to 3 or 4
dBi on resonant frequencies and dramatic
loss down to -(!)15dBi on nonresonant
ranges.


You set an unreachable standard, Volker. There is no antenna made that is
not more resonant on some frequencies and less resonant on others. Certainly
some do perform better than either the ground plane or discone, but these
antennas have their place also. Few antennas can beat the utter bandwidth of
a discone and the ground plane is ideal where an even less intrusive antenna
is desired. Indeed, I've had success with a simple wire that is probably not
directly resonant on any desired frequency. In other words, any antenna is
clearly better than nothing.


Dwight Stewart (W5NET)

http://www.qsl.net/w5net/

Dwight Stewart schrieb:

... Few antennas can beat the utter bandwidth of
a discone and the ground plane is ideal where an even less intrusive antenna
is desired.


Giving a specification(!) on a groundplane from 25-100Mhz is taking a
customer for a ride. An antenna specified(!) for a frequency *range*
implies at least that it has gain over an isotropic radiator wich is
simply not true for a groundplane "25-1000Mhz".
It would be a different thing in konjunktion with some active elctronics
-wich is not the case-.
And yes, you can have very much success on a simple antenna design. A
CB-whip with top loading coil (in europe known as DV27S -length of
1.4mtr-) is known to be a good performer on _some_ "interesting"
frequency ranges. It works on the same principle like the mentioned
groundplane when installed on a metal sheet ...at a fraction of cost
(less than 10EUR/ 13US$).

Volker

As "I" had stated, if those antennas are the only game in town and people
are wanting to buy them, not knowing how to make one, what choice is left?
Though I can build one myself and have, most people won't want a "homemade"
antenna. SO...... No antenna is "perfect". Antennas for the most part are
tested in a set of conditions usually fixed, whereas their use out side
those conditions can vary greatly. Type of cable, length, height of
installation, surroundings, etc... NO antenna can work "as" the factory
suggests, even if there are good points to the antenna. You're setting the
bar way too high. If you've got ideas for better antennas, I'm sure they'd
love to hear from you. CL.

"Volker Tonn" wrote in message
...


Dwight Stewart schrieb:

... Few antennas can beat the utter bandwidth of
a discone and the ground plane is ideal where an even less intrusive
antenna
is desired.


Giving a specification(!) on a groundplane from 25-100Mhz is taking a
customer for a ride. An antenna specified(!) for a frequency *range*
implies at least that it has gain over an isotropic radiator wich is
simply not true for a groundplane "25-1000Mhz".
It would be a different thing in konjunktion with some active elctronics
-wich is not the case-.
And yes, you can have very much success on a simple antenna design. A
CB-whip with top loading coil (in europe known as DV27S -length of
1.4mtr-) is known to be a good performer on _some_ "interesting"
frequency ranges. It works on the same principle like the mentioned
groundplane when installed on a metal sheet ...at a fraction of cost
(less than 10EUR/ 13US$).

Volker