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double biquad
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miso
Apr 25, 2012, 12:02:46 AM4/25/12
to
> http://martybugs.net/wireless/biquad/double.cgi
OK, the biquad parallels two 100 ohm loops to make 50 ohms. How does the
double biquad get away with 4 loops?
OK, the biquad parallels two 100 ohm loops to make 50 ohms. How does the
double biquad get away with 4 loops?
Jeff Liebermann
Apr 27, 2012, 12:32:53 AM4/27/12
to
If you look carefully at the double biquad, the outer two quads are
connected in series with the opposite ends of the inner two quads. The
result is 200 ohms on each side of the coax or 100 ohms in paralle.
If you look at the NEC2 results at:
<http://802.11junk.com/jeffl/antennas/DoubleBiquad/>
you'll notice that the impedance is 100 ohms, not 50 ohms with a
resultant VSWR of 2:1. (I'll make the above URL look pretty later).
--
# Jeff Liebermann 150 Felker St #D Santa Cruz CA 95060
# 831-336-2558
# http://802.11junk.com je...@cruzio.com
# http://www.LearnByDestroying.com AE6KS
miso
Apr 28, 2012, 4:09:55 AM4/28/12
to
On 4/26/2012 9:32 PM, Jeff Liebermann wrote:
> On Tue, 24 Apr 2012 21:02:46 -0700, miso<mi...@sushi.com> wrote:
>
>>> http://martybugs.net/wireless/biquad/double.cgi
>
>> OK, the biquad parallels two 100 ohm loops to make 50 ohms. How does the
>> double biquad get away with 4 loops?
>
> <http://www.lecad.fs.uni-lj.si/~leon/other/wlan/biquad/>
> If you look carefully at the double biquad, the outer two quads are
> connected in series with the opposite ends of the inner two quads. The
> result is 200 ohms on each side of the coax or 100 ohms in paralle.
> If you look at the NEC2 results at:
> <http://802.11junk.com/jeffl/antennas/DoubleBiquad/>
> you'll notice that the impedance is 100 ohms, not 50 ohms with a
> resultant VSWR of 2:1. (I'll make the above URL look pretty later).
>
>
I get it. Seems to me we need a double double biquad. Next time I'm at
> On Tue, 24 Apr 2012 21:02:46 -0700, miso<mi...@sushi.com> wrote:
>
>>> http://martybugs.net/wireless/biquad/double.cgi
>
>> OK, the biquad parallels two 100 ohm loops to make 50 ohms. How does the
>> double biquad get away with 4 loops?
>
> <http://www.lecad.fs.uni-lj.si/~leon/other/wlan/biquad/>
> If you look carefully at the double biquad, the outer two quads are
> connected in series with the opposite ends of the inner two quads. The
> result is 200 ohms on each side of the coax or 100 ohms in paralle.
> If you look at the NEC2 results at:
> <http://802.11junk.com/jeffl/antennas/DoubleBiquad/>
> you'll notice that the impedance is 100 ohms, not 50 ohms with a
> resultant VSWR of 2:1. (I'll make the above URL look pretty later).
>
>
In and Out, I will see if they have one.
Jeff Liebermann
Apr 28, 2012, 11:18:12 AM4/28/12
to
loop element and break the end opposite the feed. That gives two 50
ohm sections. Put another 100 ohm quad loop across the break point,
and we have:
50 + 100 + 50 = 200 ohms.
Put two of those in parallel, and we have a 100 ohm antenna.
You could probably get it back to 50 ohms by taking two such
double-double biquad antennas, placing them 1 wavelength apart on a
common reflector, and connecting them together using two odd multiple
of 1/4 wavelength, 75 ohm coax cables as is commonly done in collinear
dipole antennas.
Here's one attempt:
<http://www.digdice.com/diy-wifi-antenna-double-dual-biquad-16-17-dbi/>
which I think has a problem as he's assuming a 50 ohm feed point for
each double biquad.
Now, what the deleted expletive does this have to do with In and Out
burger?
--
Jeff Liebermann je...@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
alexd
Apr 28, 2012, 3:45:37 PM4/28/12
to
Jeff Liebermann (for it is he) wrote:
> Now, what the deleted expletive does this have to do with In and Out
> burger?
Does "double double" not mean anything to you? The cry of "Eight meat down!"
> Now, what the deleted expletive does this have to do with In and Out
> burger?
when you order two four by fours is priceless.
--
<http://ale.cx/> (AIM:troffasky) (UnSoEs...@ale.cx)
20:43:45 up 107 days, 23:15, 5 users, load average: 0.10, 0.31, 0.30
Qua illic est reprehendit, illic est a vindicatum
Jeff Liebermann
Apr 28, 2012, 6:56:52 PM4/28/12
to
On Sat, 28 Apr 2012 20:45:37 +0100, alexd <trof...@hotmail.com>
wrote:
>Jeff Liebermann (for it is he) wrote:
>
>> Now, what the deleted expletive does this have to do with In and Out
>> burger?
>
>Does "double double" not mean anything to you? The cry of "Eight meat down!"
>when you order two four by fours is priceless.
Sorry, but I'm culturally retarded.
I haven't been to an In and Out Burger in maybe 30 years. I might eat
two burgers per year, and that's usually at a barbeque. I have no
clue what "eight meat down" means. Google didn't help. However, I do
know what's a 4 by 4. I use 4 by 4 lumber to support my house.
wrote:
>Jeff Liebermann (for it is he) wrote:
>
>> Now, what the deleted expletive does this have to do with In and Out
>> burger?
>
>Does "double double" not mean anything to you? The cry of "Eight meat down!"
>when you order two four by fours is priceless.
I haven't been to an In and Out Burger in maybe 30 years. I might eat
two burgers per year, and that's usually at a barbeque. I have no
clue what "eight meat down" means. Google didn't help. However, I do
know what's a 4 by 4. I use 4 by 4 lumber to support my house.
amdx
Apr 28, 2012, 8:16:27 PM4/28/12
to
On 4/28/2012 5:56 PM, Jeff Liebermann wrote:
> On Sat, 28 Apr 2012 20:45:37 +0100, alexd<trof...@hotmail.com>
> wrote:
>
>> Jeff Liebermann (for it is he) wrote:
>>
>>> Now, what the deleted expletive does this have to do with In and Out
>>> burger?
>>
>> Does "double double" not mean anything to you? The cry of "Eight meat down!"
>> when you order two four by fours is priceless.
>
> Sorry, but I'm culturally retarded.
>
> I haven't been to an In and Out Burger in maybe 30 years. I might eat
> two burgers per year, and that's usually at a barbeque. I have no
> clue what "eight meat down" means. Google didn't help. However, I do
> know what's a 4 by 4. I use 4 by 4 lumber to support my house.
>
>
That's all beyond my cultural experience also. Oh, I used 4x4s to
> On Sat, 28 Apr 2012 20:45:37 +0100, alexd<trof...@hotmail.com>
> wrote:
>
>> Jeff Liebermann (for it is he) wrote:
>>
>>> Now, what the deleted expletive does this have to do with In and Out
>>> burger?
>>
>> Does "double double" not mean anything to you? The cry of "Eight meat down!"
>> when you order two four by fours is priceless.
>
> Sorry, but I'm culturally retarded.
>
> I haven't been to an In and Out Burger in maybe 30 years. I might eat
> two burgers per year, and that's usually at a barbeque. I have no
> clue what "eight meat down" means. Google didn't help. However, I do
> know what's a 4 by 4. I use 4 by 4 lumber to support my house.
>
>
hold up a fence.
But Jeff, you could do the wifi DIY's a big help if you could perfect
the double double and still keep it simple.
I wonder if the pcb is a stripline that is used to transform the
impedances? That would be the most difficult part for many.
If you can't design it to eliminate the stripline transformer (if that's
what it is) you could sell the pcb!.
I like it because the construction is so simple.
Can you really get 16-17 db gain in 7" x 7"? :-)
Mikek
miso
Apr 28, 2012, 9:39:56 PM4/28/12
to
On 4/28/2012 3:56 PM, Jeff Liebermann wrote:
> On Sat, 28 Apr 2012 20:45:37 +0100, alexd<trof...@hotmail.com>
> wrote:
>
>> Jeff Liebermann (for it is he) wrote:
>>
>>> Now, what the deleted expletive does this have to do with In and Out
>>> burger?
>>
>> Does "double double" not mean anything to you? The cry of "Eight meat down!"
>> when you order two four by fours is priceless.
>
> Sorry, but I'm culturally retarded.
>
> I haven't been to an In and Out Burger in maybe 30 years. I might eat
> two burgers per year, and that's usually at a barbeque. I have no
> clue what "eight meat down" means. Google didn't help. However, I do
> know what's a 4 by 4. I use 4 by 4 lumber to support my house.
>
>
It is part of the secret menu at In and Out. It isn't so secret since
> On Sat, 28 Apr 2012 20:45:37 +0100, alexd<trof...@hotmail.com>
> wrote:
>
>> Jeff Liebermann (for it is he) wrote:
>>
>>> Now, what the deleted expletive does this have to do with In and Out
>>> burger?
>>
>> Does "double double" not mean anything to you? The cry of "Eight meat down!"
>> when you order two four by fours is priceless.
>
> Sorry, but I'm culturally retarded.
>
> I haven't been to an In and Out Burger in maybe 30 years. I might eat
> two burgers per year, and that's usually at a barbeque. I have no
> clue what "eight meat down" means. Google didn't help. However, I do
> know what's a 4 by 4. I use 4 by 4 lumber to support my house.
>
>
you can find the "off the menu" items on the internet. Technically, I
don't believe a double double is a legit meal, which is why google
didn't help. You would ask for a four by four.
Jeff Liebermann
Apr 28, 2012, 10:29:40 PM4/28/12
to
On Sat, 28 Apr 2012 19:16:27 -0500, amdx <am...@knologynotthis.net>
wrote:
> But Jeff, you could do the wifi DIY's a big help if you could perfect
>the double double and still keep it simple.
My idea of simple is the Franklin/Amos antenna. See various examples
near the top of:
<http://802.11junk.com/jeffl/antennas/>
The main problem with building a double-double biquad or AMOS is the
wire standoffs. Cheezy nylon doesn't work. Custom ceramic or glass
are tempting if you're into pottery or working glass. It's really
tempting to make the entire AMOS wire antenna out of a polysufone (not
G10/FR4) PCB (printer circuit board). That's easy for the AMOS as it
could be single sided, but with the double-double biquad, it would
need to be etched on both sides to deal with the crossover. If you're
going to build just one, all this is irrelevant. If you're going to
manufacture, it's vital.
I'll throw together a proper NEC model and offer some construction
ideas for do-it-thyself constructions. With semi-rigid coax, the
double double biquad is quite easy. However, no now. I'm busy with
paying work.
> I wonder if the pcb is a stripline that is used to transform the
>impedances? That would be the most difficult part for many.
I can't figure out what he's trying to do. Each double biquad section
has a 100 ohm feed point impedance. One could parallel two of these
to get 50 ohms, if they were on top of each other, or separated by any
multiple of 1/2 wave sections of mythical 100 ohm coax cable. (75
ohms would be close enough). Yet, the stepped PCB strip line in the
photo is doing something else, which I can't guess without dimensions
or a description.
The original design apparently came from this site:
<http://www.zero13wireless.net/foro/forumdisplay.php?46-Antenas-Direccionales-Wireless&s=761a47b653870eb321cd3ed14ca58cb7>
but I can't find it.
>If you can't design it to eliminate the stripline transformer (if that's
>what it is) you could sell the pcb!.
No thanks. I can make money selling expensive antennas (or expensive
consulting), but not cheap antennas for experimenters. If you want
cheap and easy, think about multiple patch antennas on PCB material.
For example:
<http://www.ebay.com/itm/170778036572>
14dBi gain is a bit optimistic, because it ignores matching section
losses. My guess is 12dBi maximum on a 5.5" x 5.5" PCB. I have
several of these, but have never bothered to measure the gain or sweep
the VSWR.
>I like it because the construction is so simple.
I don't think it's that simple. Permit me to remind you that things
become more critical as the gain goes up. One can be rather sloppy
when building antennas with gains of less than about 12dBi. Higher
gains require a pile of test equipment and some precision
construction.
>Can you really get 16-17 db gain in 7" x 7"? :-)
<http://802.11junk.com/jeffl/antennas/DoubleBiquad/index.html>
Close. Doubling the size of an antenna yields 3dB more gain. The
model for the original double biquad claims 13.5dBi gain. Two of
these, properly combined, minus about 1dB combiner loss, would yield:
13.5 + 3.0 - 1.0 = 15.5dBi gain
Using lossy materials (i.e. leaky standoffs, lossy coax, and lossy PCB
material) will reduce this some unknown amount. The 15.5dBi is the
very best that can be done. Your mileage will be less.
wrote:
> But Jeff, you could do the wifi DIY's a big help if you could perfect
>the double double and still keep it simple.
near the top of:
<http://802.11junk.com/jeffl/antennas/>
The main problem with building a double-double biquad or AMOS is the
wire standoffs. Cheezy nylon doesn't work. Custom ceramic or glass
are tempting if you're into pottery or working glass. It's really
tempting to make the entire AMOS wire antenna out of a polysufone (not
G10/FR4) PCB (printer circuit board). That's easy for the AMOS as it
could be single sided, but with the double-double biquad, it would
need to be etched on both sides to deal with the crossover. If you're
going to build just one, all this is irrelevant. If you're going to
manufacture, it's vital.
I'll throw together a proper NEC model and offer some construction
ideas for do-it-thyself constructions. With semi-rigid coax, the
double double biquad is quite easy. However, no now. I'm busy with
paying work.
> I wonder if the pcb is a stripline that is used to transform the
>impedances? That would be the most difficult part for many.
has a 100 ohm feed point impedance. One could parallel two of these
to get 50 ohms, if they were on top of each other, or separated by any
multiple of 1/2 wave sections of mythical 100 ohm coax cable. (75
ohms would be close enough). Yet, the stepped PCB strip line in the
photo is doing something else, which I can't guess without dimensions
or a description.
The original design apparently came from this site:
<http://www.zero13wireless.net/foro/forumdisplay.php?46-Antenas-Direccionales-Wireless&s=761a47b653870eb321cd3ed14ca58cb7>
but I can't find it.
>If you can't design it to eliminate the stripline transformer (if that's
>what it is) you could sell the pcb!.
consulting), but not cheap antennas for experimenters. If you want
cheap and easy, think about multiple patch antennas on PCB material.
For example:
<http://www.ebay.com/itm/170778036572>
14dBi gain is a bit optimistic, because it ignores matching section
losses. My guess is 12dBi maximum on a 5.5" x 5.5" PCB. I have
several of these, but have never bothered to measure the gain or sweep
the VSWR.
>I like it because the construction is so simple.
become more critical as the gain goes up. One can be rather sloppy
when building antennas with gains of less than about 12dBi. Higher
gains require a pile of test equipment and some precision
construction.
>Can you really get 16-17 db gain in 7" x 7"? :-)
Close. Doubling the size of an antenna yields 3dB more gain. The
model for the original double biquad claims 13.5dBi gain. Two of
these, properly combined, minus about 1dB combiner loss, would yield:
13.5 + 3.0 - 1.0 = 15.5dBi gain
Using lossy materials (i.e. leaky standoffs, lossy coax, and lossy PCB
material) will reduce this some unknown amount. The 15.5dBi is the
very best that can be done. Your mileage will be less.
isw
Apr 29, 2012, 12:34:19 AM4/29/12
to
In article <jng8kc$ho1$1...@speranza.aioe.org>, miso <mi...@sushi.com>
wrote:
Be sure to ask for it "Animal Style".
Isaac
wrote:
Isaac
alexd
Apr 29, 2012, 8:40:15 AM4/29/12
to
miso (for it is he) wrote:
> It is part of the secret menu at In and Out. It isn't so secret since
> you can find the "off the menu" items on the internet. Technically, I
> don't believe a double double is a legit meal, which is why google
> didn't help. You would ask for a four by four.
double double = two meat, two cheese
> It is part of the secret menu at In and Out. It isn't so secret since
> you can find the "off the menu" items on the internet. Technically, I
> don't believe a double double is a legit meal, which is why google
> didn't help. You would ask for a four by four.
four by four = four meat, four cheese
You order two four by fours and they'll need to grill eight patties.
13:38:05 up 108 days, 16:09, 5 users, load average: 0.09, 0.14, 0.46
miso
Apr 29, 2012, 8:13:11 PM4/29/12
to
> Be sure to ask for it "Animal Style".
>
> Isaac
don't like a lot of sauce on my food. IIRC, animal style used a lot of
mustard.
Incidentally, you can ask for the fries to be well done.
While we're at it, the last tidbit of In and Out useless trivia is the
bottom of the cups have bible verses on them. One of the previous CEOs
was quite the bible thumper, not that it saved his arse from dying in a
plane crash.
amdx
Apr 29, 2012, 8:49:38 PM4/29/12
to
And I guess everyone else on the plane too.
Funny how he got them all on the same plane,
but I guess he can do that too.
Mikek, in an agnostic mood
I think there ain't no heaven but I pray there ain't not hell.
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