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bmoore314
Mini
Stumbler

Registered: Jun
2002
Location: south bay area, california
Posts:
19

Nice antenna
there lincomatic, maybe I'm gonna have to try that design
next. It looked really difficult from the guerilla.net
instructions, so I stayed away from it. Your page makes it
look easy. I am guessing the reason you signal strength was
fluctuation so much was from excess noise, and such. With a
larger antenna, especially an omni, you amplify the noise as
well as the signal. My waveguide with a collector was pretty
erratic during the day, and solid during the night. My new
dish one gives a strong signal during the day, and even
stronger at night. Probably due to the narrow beamwidth of a
dish, blocks out more noise than just a plain waveguide. Just
my $0.02

Brian

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07-22-2002 04:51
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lincomatic
Squaawwkkk!

Registered: Apr
2002
Location: Congo
Posts: 1062

i hope i made
it a bit more understandable. I was kind of skeptical of the
design at first, and it looked like a lot of work to build,
but seeing that it matched the Lucent/Maxrad convinced me that
it was a good design.

I didn't have any screws handy to
aid in winding the coils...man my fingers still hurt! some
people have suggested building a jig by driving the screw into
a block of wood and drilling a small hole into the wood beside
it to catch the wire. it still takes hours to build compared
to my other antennae which were pretty easy & fast. but i
am pretty impressed w/ the results.

as for the signal
fluctuation, i often get that during the day. it was
fluctuating with both the built-in antenna and the omni.
usually i get the most stable readings late at nite when it's
cool like after 2am.

stupid me...left the omni out on
my deck to bake the epoxy in the sun...the wind blew it off
and it fell to the ground 40ft below and completely fell
apart. argh! had to spend over 1/2 hr reassembling it after
that.

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07-22-2002 04:59
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sparafina
semiotech

Registered: May
2002
Location: AUS/LAX/DCA
Posts: 223

Re: collinear omni
rocks

quote:

Originally posted by lincomatic
I finally
built the gnet low power collinear. Took forever, but it's
done, and it works great. full story:

http://www.geocities.com/lincomatic/collinear.html

I'm
going to try closing my sunroof onto it and stumbling with
it when i run some errands today.

Way cool page, much better than the
original instructions. Have sent you the g.net archives I
have.

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07-23-2002 02:17
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lincomatic
Squaawwkkk!

Registered: Apr
2002
Location: Congo
Posts: 1062

for anyone
who wants to do antenna modeling with NEC2,
here is
a great tutorial:

http://www.antennex.com/w4rnl/

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07-23-2002 02:49
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norm
Mini Stumbler

Registered: May
2002
Location: UK
Posts: 19

will you
consider building a WaveGuide next Linomatic, it looks a
really clean/efficient design

http://www.narx.net/~mike/projects/waveguide/

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07-23-2002 09:07
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lincomatic
Squaawwkkk!

Registered: Apr
2002
Location: Congo
Posts: 1062

norm,

yes, slotted waveguides are very cool.
trevor marshall has a design too:

http://trevormarshall.com/waveguides.htm

but
it will probably be a while before i build one of these
because:
1) it doesn't fit my idea of cheap (that mike guy
spent $250!) and here i was moaning about the collinear
costing me $11 ... i have yet to find a good source for the
extrusions...
2) the thing is huge! i don't really have a
use for such a beast at the moment.

but the coolness
factor beckons...don't tempt me

i'm going to at least wait until
sparafina builds his first.

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07-23-2002 09:45
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norm
Mini Stumbler

Registered: May
2002
Location: UK
Posts: 19

i think that
may have been $250 (Austrailian dollars) which works out as
about $135 US

need to find a place to machine it for a
similar price now

i like your collinear article btw.

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07-23-2002 09:56
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lincomatic
Squaawwkkk!

Registered: Apr
2002
Location: Congo
Posts: 1062

quote:

Originally posted by norm
i think that may
have been $250 (Austrailian dollars) which works out as
about $135 US

need to find a place to machine it for
a similar price now

i like your collinear article btw.

if you can get an affordable source for
the extrusion (some guys bought them for $USD35-50, you can
save a lot of $$ by cutting the slots yourself. trevor
marshall just used hand tools on his.

glad you found my
collinear article useful. it's been such a big chore digging
up info from the internet on building 2.4GHz antennae....i'm
trying to build up a repository of info now. seems like sites
are disappearing all the time.

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07-23-2002 10:04
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sparafina
semiotech

Registered: May
2002
Location: AUS/LAX/DCA
Posts: 223

quote:

Originally posted by lincomatic
yes, slotted
waveguides are very cool.
i'm going to at least wait
until sparafina builds his first.

I'm still looking around for usable
aluminum extrusion, I need to pay a visit to the local junk
yards for car parts anyway.

I'm thinking of using foil covered foam core
for a prototype, a la Christoph Catelain's (http://users.skynet.be/chricat/BT.html)
experiments (see bottom of page). I'll try an meet up with him
in September, need to brush up on my technical french.

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07-24-2002 06:17
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lincomatic
Squaawwkkk!

Registered: Apr
2002
Location: Congo
Posts: 1062

quote:

Originally posted by sparafina
I'm thinking of
using foil covered foam core for a prototype, a la Christoph
Catelain's (http://users.skynet.be/chricat/BT.html)
experiments (see bottom of page). I'll try an meet up with
him in September, need to brush up on my technical french.

that's a great idea! or how about
foil-covered corrugated cardboard? maybe we can sell them on
ebay!

have u made contact w/ Christoph Catelain?
that would be cool to meet him ... he must have a lot of
knowledge from all that experimenting he's done.

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07-24-2002 09:00
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sparafina
semiotech

Registered: May
2002
Location: AUS/LAX/DCA
Posts: 223

got motivated
and did some lateral thinking after reading the herf and
microwave threads.

these links are archives from
homepower magazine for building a microwave leakage detector.
The scanned diagram is crap, but a good tease. Will need to
find a dead tree edition if possible.

http://www.ibiblio.org/pub/academic/environment/alternative-energy/energy-resources/homepower-magazine/archives/35/35p68.txt

http://www.ibiblio.org/pub/academic/environment/alternative-energy/energy-resources/homepower-magazine/archives/35/35p72.gif

http://www.ibiblio.org/pub/academic/environment/alternative-energy/energy-resources/homepower-magazine/archives/35/35p72.txt

here's
the interesting stuff from the first article:

Some
Technical Notes About Microwaves and Their
Measurement
Microwaves are a non-ionizing radiation
comprising part of the
electromagnetic spectrum from about
0.3 GHz to 300 GHz. GHz
stands for gigahertz or one
billion vibrations per second. All
electromagnetic waves
travel through free space at a speed of
about 300 million
meters per second. The length of any given
wave in space
(LAMBDA) is the speed of propagation divided by
its
frequency (Ÿ),
Or: LAMBDA = 30/Ÿ
Ÿ = 30/ LAMBDA
for
wavelengths in centimeters and frequency in gigahertz
For a
microwave oven:
Ÿ = 2.45 GHz, LAMBDA = 30/Ÿ, LAMBDA =
30/2.45, LAMBDA =
12.24 cm or 4.82 inches
Microwave
power is measured in units, and in units per area
space.
For example, a typical microwave oven will generate
about
700 total watts of power and the leakage, measured 5 cm

from the unit might be 0.1 milliwatt per square centimeter

(cm2), or 100 microwatts per cm2. One milliwatt = 1/1000

watt and microwatt = 1/1,000,000 watt. Ideally microwaves

radiate from a source in spherical waves the power density
of
which is proportional to the inverse square of the
distance to
the source. If the distance is doubled (D = 2)
power is 1/2^2 or
X1/4. If the distance is halved, (D =
0.5) power is 1/(0.5)^2 or
X4. Power measurements made
within one wavelength or so of a
source (near field) will
exhibit irregularities due to power
storage and exchange
in the elements of the radiating part.
The natural
microwave power level
It is challenging to compare a single
frequency modulated
signal such as a microwave oven
leakage to the complex sum of
microwave power exposure
from nature. For this article I have
assumed that the
power of natural microwave radiation at 2.45
GHz can be
estimated as a an audio bandwidth modulation of
290øK [THE
POWER OF NATURAL MICROWAVE RADIATION AT 2.45
GHZ CAN BE
ESTIMATED AS] an audio bandwidth modulation of
290øK
microwave noise centered on 2.45 GHz is analogous. This

may or may not be true. Natural microwave noise power = PN
=
kTB where:
PN = noise power (watts)
k =
Boltzmann's constant (J/K)
B = bandwidth (Hz)
T =
temperature (K)
Given T = 290øK, B = 20 kHz, PN = 8 x 10-17
watts.
The "Cantanna" is a circular waveguide to coaxial
transition
with a point contact diode mounted as a shunt
element. The
extended wire serves as an E (electrostatic)
field probe. For the
TEll mode the circular guide exhibits
cutoff at a wavelength
equal to 1.7 times the diameter.
The next mode will exist at 1.3
times the diameter. The
coffee can is optimized for frequencies
near 2.45 GHz but
is sensitive to others as well. It has a
polarization axis
parallel to the E field probe and should be
rotated during
measurement for the strongest detected signal.

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07-24-2002 09:23
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lincomatic
Squaawwkkk!

Registered: Apr
2002
Location: Congo
Posts: 1062

cool. that
looks like a low-cost version of trevor marshall's microwave
detector he demoed @ the first SocalWUG meeting.

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07-24-2002 09:28
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sparafina
semiotech

Registered: May
2002
Location: AUS/LAX/DCA
Posts: 223

quote:

Originally posted by lincomatic

that's
a great idea! or how about foil-covered corrugated
cardboard? maybe we can sell them on ebay!

have u made contact w/ Christoph Catelain?
that would be cool to meet him ... he must have a lot of
knowledge from all that experimenting he's done.

I live in fairly humid area, so I've
ruled out carboard. I need to stick the foam core into the
microwave and see if it absorbs the waves, the foil should be
fine but the slots may need to be covered.. Another thought is
the foil covered sheathing they put on new housing
construction, a trip to the construction dumpster is in
order.

I'd love to sell cantennas on ebay, spray paint
them olive drab with flat black print to make them look
surplus, but that's an awful lot of beans to eat.

Actually a light weight slotted waveguide
built with foamcore and reinforced with fiberglass or monoque
would be pretty cool.

I just bought the ticket to
Amsterdam, so I'll email Christof and see if we can meet for a
beer in Liege.

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07-24-2002 09:54
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lincomatic
Squaawwkkk!

Registered: Apr
2002
Location: Congo
Posts: 1062

my roof has
this rigid foam insulation sandwiched in aluminum sheeting on
both sides. wonder if it would be good for a waveguide. next
time i'm at home despot i'll pick some up. maybe i'll be
making a waveguide after all

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07-24-2002 10:12
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sparafina
semiotech

Registered: May
2002
Location: AUS/LAX/DCA
Posts: 223

quote:

Originally posted by lincomatic
my roof has
this rigid foam insulation sandwiched in aluminum sheeting
on both sides. wonder if it would be good for a waveguide.
next time i'm at home despot i'll pick some up. maybe i'll
be making a waveguide after all

that's the stuff I'm thinking of. BTW, on
trevor marshall site the plans for the 16 slot are also
available, but not linked. You can get it here:

www.trevormarshall.com/wave16.zip

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07-24-2002 11:11
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lincomatic
Squaawwkkk!

Registered: Apr
2002
Location: Congo
Posts: 1062

thanks for
the link. man, inside dimensional tolerance 0.5%. that's going
to be tough with foam since it's so floppy. i wonder how
critical the outside dimension is, or if it even matters. i
like your fiberglass ideas...thinking of some groovy paint
jobs like on surfboards...antennas don't have to be ugly
anymore

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07-24-2002 11:56
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sparafina
semiotech

Registered: May
2002
Location: AUS/LAX/DCA
Posts: 223

quote:

Originally posted by lincomatic
thanks for the
link. man, inside dimensional tolerance 0.5%. that's going
to be tough with foam since it's so floppy. i wonder how
critical the outside dimension is, or if it even matters. i
like your fiberglass ideas...thinking of some groovy paint
jobs like on surfboards...antennas don't have to be ugly
anymore

Presenting the 20 dbi Mulletboy slotted
waveguide!

sparafina has attached this image:

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07-24-2002 12:22
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bmoore314
Mini
Stumbler

Registered: Jun
2002
Location: south bay area, california
Posts:
19

I think
picking up an ap from 4 miles away is pretty cool. The link
I'm working on is a couple blocks away, through some nasty
trees, much interference. Maybe I'll take a pic of the area
that my dish is aimed at. If I got me a pole large enough to
get above the trees, I could pick up the ap from my
work(apple) cause they have a large airport network, with some
big ass omni's on the roof of each building. You can get a
signal from anywhere on the grounds. Unfortuneately, my
parents barely allow me to have my satelite on the roof as it
is. Oh well, when I move out maybe I'll have better mounting
options.

Brian

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07-25-2002 09:06
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slunk
Mini
Stumbler

Registered: Jun
2002
Location:
Posts: 8

I'm finally
getting into this. I ordered my pigtail the other day, and now
I am looking for female N connectors. I can't find any in my
town. Radio Shack has no idea what I'm talking about, and I
can't find anything on their shelves. Does this look
good:

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07-25-2002 10:40
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lincomatic
Squaawwkkk!

Registered: Apr
2002
Location: Congo
Posts: 1062

that appears
to be an N-female jack

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07-25-2002 10:48
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lincomatic
Squaawwkkk!

Registered: Apr
2002
Location: Congo
Posts: 1062

more slotted waveguide
info

here is some
more info on slotted waveguide design, including programs for
calculating dimensions:

http://www.ij.net/packrats/Slot_Antenna/slot.html

i
think i'm going to put off the waveguide and build another
collinear with more sections first. i'm a bit apprehensive
about the 1mm tolerance for the internal dimension on the
slotted waveguides, and haven't yet found a good source for
the aluminum foil/foam sandwich yet.

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07-25-2002 10:56
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Thorn
Part man, part
machine...

Registered: Apr
2002
Location: Tír na nÓg
Posts: 508

quote:

Originally posted by slunk
I'm finally getting
into this. I ordered my pigtail the other day, and now I am
looking for female N connectors. I can't find any in my
town. Radio Shack has no idea what I'm talking about, and I
can't find anything on their shelves. Does this look
good:

It looks like a female, panel mount N.
But what does the catalogue or web page say? You need a N
rated for microwave connections. Most are, but check the
specs.

BTW, Rat Shack CAN order N connectors. They are
a special order out of the "Archer" catalog (Archer is RS's
professional supplies division. You have to ask to even know
it exists.) Ask for the Manager, and tell them that's what you
want to do. You pay then (about $3.00 ea) and RS will ship the
order directly to you.

Most of the people that RS hires
are only good for selling a CD player or something. They know
zilch about electonic components. The managers are usually
slightly better. They at least know the Archer catalog is
available. If you find a geek working at a RS, (usually a ham)
they can be worth their weight in gold. They are the ones who
will know a resistor from a diode, and can help you get the
right items.

Good luck.

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07-26-2002 06:08
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lincomatic
Squaawwkkk!

Registered: Apr
2002
Location: Congo
Posts: 1062

coil antenna

thesovereign has posted a couple of interesting
designs in this thread:
http://forums.netstumbler.com/showthread.php?s=&postid=21554

would
someone pls join the fun and build one?

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07-29-2002 09:37
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biko
Mini Stumbler

Registered: Jul
2002
Location:
Posts: 4

MIT chemicals
can

I built an
antenna from an old chemicals box I found at my lab. It has a
diameter of approx 6.5 inches (16 cm) and is 11 inches (27.5
cm) long. I built it with the instructions from this
site:

http://www.turnpoint.net/wireless/cantennahowto.html

I
get about a gain of 20db, although I don´t have an AP myself
so I don´t know exactly.

If anyone is interested I can
mail pics of the antenna.

What do you guys think ? Is
that reasonable or did I screw the design up somehow
?
Thanks a lot
biko

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07-29-2002 03:23
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lincomatic
Squaawwkkk!

Registered: Apr
2002
Location: Congo
Posts: 1062

welcome,
biko,

+20dB for a cantenna is wishful thinking.
especially for the large diameter can you are using. 16cm is
too big. the TE11 cutoff is 1098MHz and TM01 cutoff is
1434MHz. your antenna is tuned too low.

btw you an
attach a pic to your post if you like.

and please,
crossposting is a no-no. each message should go to only
1 thread. pls delete the other one.

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07-29-2002 04:52
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biko
Mini Stumbler

Registered: Jul
2002
Location:
Posts: 4

hey,
thanks for the answer...sorry for the
cross-posting, i deleted the other thread !
this is the way
i tried to estimate my gain: i sat in front of a house with an
AP and got about 10 reading on the Orinoco software for
signal/noise ration.
With the antenna plugged in, I got
about 30 reading ! I thought this meant a 20db gain, but
correct me if I´m wrong.
You are right, my antenna IS tuned
too low, but on this site (my link 2 posts before) it says you
can go bigger:

The size doesn't have to be exact. I
made a good antenna with a Nalley's "Big Chunk" Beef Stew can
that was 3.87" in diameter. Others have reported good results
with big 39oz. coffee cans that are 6" in diameter

So I
think I should try a smaller can and compare the
readings.
Any more hints are very welcome though
!!
Thanks
biko

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07-29-2002 05:28
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Thorn
Part man, part
machine...

Registered: Apr
2002
Location: Tír na nÓg
Posts: 508

quote:

Originally posted by biko
hey,
thanks for
the answer...sorry for the cross-posting, i deleted the
other thread !
this is the way i tried to estimate my
gain: i sat in front of a house with an AP and got about 10
reading on the Orinoco software for signal/noise
ration.
With the antenna plugged in, I got about 30
reading ! I thought this meant a 20db gain, but correct me
if I´m wrong.
You are right, my antenna IS tuned too low,
but on this site (my link 2 posts before) it says you can go
bigger:

The size doesn't have to be exact. I made a
good antenna with a Nalley's "Big Chunk" Beef Stew can that
was 3.87" in diameter. Others have reported good results
with big 39oz. coffee cans that are 6" in diameter

So
I think I should try a smaller can and compare the
readings.
Any more hints are very welcome though
!!
Thanks
biko

Welcome biko.
You are correct in
measuring the signal increase it the rough way to get an
estimate of the antenna's gain. But I really question 20db on
a cantenna. You say " i sat in front of a house with an AP and
got about 10 reading on the Orinoco software for signal/noise
ration." Tell me, are you inside a vehicle when you take your
initial reading? Is the cantenna then pointed out the window?
That, or some other obstruction between the card and the AP
might account for the difference.

A better method it to
use an external antenna of a known gain, to take an initial
reading. Then replace the known attenna with the cantenna,
using the same placement, the same pigtail and the same
connecting coax. In other words, reduce the varaibles to just
the antenna. Then subtract the initial reading from the
(hopefully) increase. Don't forget to factor in the gain of
the first antenna, too. Doing this in an open area, with
nothing between you and the AP is also the best
practice.

BTW, don't assume that because someone got
something to work, that the correct size isn't critical. "The
size doesn't have to be exact." Sure, it may work, but does it
work well? The more exact, the better the performace. Size is
very important in this stuff for good results. Being 1mm off
at these frequencies is enough to degrade performance. Try to
be as exact as possible.

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07-29-2002 06:18
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Thorn
Part man, part
machine...

Registered: Apr
2002
Location: Tír na nÓg
Posts: 508

Re: coil
antenna

quote:

Originally posted by lincomatic

thesovereign has posted a couple of
interesting designs in this thread:
http://forums.netstumbler.com/showthread.php?s=&postid=21554

would
someone pls join the fun and build one?

OK linc, I am intrigued.

I've got
some 12 ga left over from the last remodeling. All I need to
do is find a 7.5 mm form.

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07-29-2002 06:23
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lincomatic
Squaawwkkk!

Registered: Apr
2002
Location: Congo
Posts: 1062

Re: Re: coil
antenna

quote:

Originally posted by Thorn

OK linc, I
am intrigued.

I've got some 12 ga left over from the
last remodeling. All I need to do is find a 7.5 mm form.

c00l. i went thru my box of drill bits
until and found one exactly 7.5mm ... my screwdrivers were all
too small.

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07-29-2002 06:35
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lincomatic
Squaawwkkk!

Registered: Apr
2002
Location: Congo
Posts: 1062

biko,
one thing people often forget when
comparing antenna gains is taking orientation and polarization
into account. carefully experiment with the positioning and
rotation of each antenna until you get the maximum value.
record the maximum value for each antenna, and then subtract
them to get the gain.

for instance, the cantenna's
polarization is dependent on the orientation of the internal
probe. rotate the antenna about its axis, and the polarization
changes from horizontal to vertical, and the gain changes
dramatically. similarly, with the orinoco built-in antenna, if
hold the card parallel to the ground or vertical, you will get
dramatically different readings. the orinoco antenna actually
works best when held vertically, with the flat part facing the
AP, and even then you need to rotate it until you get the max
reading.

you need to be careful that you're not
penalizing one antenna due to its orientation.

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07-29-2002 08:03
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biko
Mini Stumbler

Registered: Jul
2002
Location:
Posts: 4

hey
lincomatic and thorn,
thanks again for the answers ! i
wouldn´t have thought that you guys take so much care of
newbies ! great to be here !

to describe it a little
more in detail:
i had the laptop with the orinoce on the
car roof and the card facing the house (where i assume the AP
is). i didn´t hold the card vertically though (that might look
a little strange, but i will try).
with this setup, about
60 feet from the house, i got a 10db reading at maximum. it
was fluctuating between 7-10. with the antenna plugged in, and
the antenna pointed direvtly towards the house ( i rotated the
antenna to get the best gain) i got a max of 30.
i tried
another can yesterday - not on the same house though - and it
seems to have the same or better gain. it is a 26oz pasta
sauce can - 3.2 inches diameter and 5.5 inches long.
maybe
i´ll go to that house again and try, but i am satisfied with
the results for now.
in the next days im gonna buy some
more chassis connectors and cans and try a real cantenna
shootout !
thanks again guys.
take
care
biko

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07-30-2002 02:10
PM

biko
Mini Stumbler

Registered: Jul
2002
Location:
Posts: 4

sorry, i
forgot something:
i don´t have an antenna of known gain and
not even the money to buy one right now !
when i get done
with my studies, and get to work i might be able to afford one
!
since im going back to germany then and the laws over
there are not so strict, i might buy a real huge one !
something like that satellite truck...
biko

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07-30-2002 02:16
PM

lincomatic
Squaawwkkk!

Registered: Apr
2002
Location: Congo
Posts: 1062

biko,
you're on the right track now
i don't have an antenna of known gain, either.
most of us don't. that's why you'll often see gains of
homebrews posted relative to the built-in ORiNOCO
antenna...that's what i always do because everyone has one of
those. Of course, the cabling will also factor in some loss,
most people just have a short pigtail connected when taking
the readings.

btw, i do most of my measurements with a
PocketPC, so it's easier for me to play w/ the orientation of
the ORiNOCO card, but to give you an example, from where i am
sitting now, the SNR jumps from 30 to 43 just by facing the
flat part of the antenna towards my AP (antenna vertical)
instead of having it in the normal position one would have in
a laptop computer.

__________________
~lincomatic

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07-30-2002 02:38
PM

sparafina
semiotech

Registered: May
2002
Location: AUS/LAX/DCA
Posts: 223

Commercial version of
antenna on FRARS

A friend of
mine was nice enough to send pictures of his antenna. Its
similar to antenna described in FRARS. I don't know the
manufacturer, but will post soon as I found out.
sparafina has attached this image:

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07-30-2002 07:20
PM

sparafina
semiotech

Registered: May
2002
Location: AUS/LAX/DCA
Posts: 223

Commercial version of
antenna on FRARS

Another
picture:
sparafina has attached
this image:

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07-30-2002 07:21
PM

lincomatic
Squaawwkkk!

Registered: Apr
2002
Location: Congo
Posts: 1062

Re: Commercial version
of antenna on FRARS

quote:

Originally posted by sparafina
A friend of
mine was nice enough to send pictures of his antenna. Its
similar to antenna described in FRARS. I don't know the
manufacturer, but will post soon as I found out.

any idea about advertised gain or other
specs?

__________________
~lincomatic

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07-30-2002 07:41
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slunk
Mini
Stumbler

Registered: Jun
2002
Location:
Posts: 8

Re: Re:
@lincomatic

quote:

Originally posted by lincomatic

i got
mine at a local radio supply house. it was in an unmarked
bag so i don't have a part number but you can get it
here:

http://www.pl-259.com/page1.html

it's
the N female chassis mount, 4-hole $2.00

btw
which antenna are you going to build?

Anybody order from them before? I was
thinking about a couple of the above posted and an "N female
chassis mount, with nut" (directly below chassis mount on web
site). Will those be all I need, n connector wise, to build a
few antennas? I can't justify buying these from fab-corp, when
TE has them much cheaper.

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07-31-2002 10:50
PM

lincomatic
Squaawwkkk!

Registered: Apr
2002
Location: Congo
Posts: 1062

Re: Re: Re:
@lincomatic

quote:

Originally posted by slunk

Anybody order
from them before? I was thinking about a couple of the above
posted and an "N female chassis mount, with nut" (directly
below chassis mount on web site). Will those be all I need,
n connector wise, to build a few antennas? I can't justify
buying these from fab-corp, when TE has them much cheaper.

not directly, but they were recommended
to me. you can get either style N jack. it's a good idea to
get 2-4. you will use 1 for each antenna and if you're not
careful you can melt them when soldering the center conductor,
so spares are nice.

__________________
~lincomatic

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07-31-2002 10:59
PM

sparafina
semiotech

Registered: May
2002
Location: AUS/LAX/DCA
Posts: 223

Re: Re: Commercial
version of antenna on FRARS

quote:

Originally posted by lincomatic

any
idea about advertised gain or other specs?

He thinks its an Enterasys, but I
couldn't find a matching one on their website. Fungus used to
sell these on ebay as well as mobile mark.

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08-01-2002 10:48
AM

lincomatic
Squaawwkkk!

Registered: Apr
2002
Location: Congo
Posts: 1062

Re: Re: Re: Commercial
version of antenna on FRARS

quote:

Originally posted by sparafina

He
thinks its an Enterasys, but I couldn't find a matching one
on their website. Fungus used to sell these on ebay as well
as mobile mark.

looks very similar to this maxrad
MUF24005 - "open coil" 8.75" antenna height, 5dBi.

http://www.maxrad.com/maxrad_products/broadband/2-6ghz/pdf/mobile_series_24_ghz.pdf

lincomatic has attached this image:

__________________
~lincomatic

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08-01-2002 11:30
AM

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