Antenna connector Linksys WRT

Since my D-link DI-614+ died, I've replaced it with a Linksys WRT54GL
router. I had an external D-link AN24 antenna on my old router. The
antenna has a cable with an N connector and a (reversed?) SMC connector
and the latter one connected with the router.

Now my new Linksys WRT54GL has a reversed TNC connector. Can I use my
old external antenna after replacing the SMC connector with a TNC
connector or are the antenna's with different types of connectors
inherently different?

"Sjeng" <sjengs2000@yahoo.com> wrote in message
> Since my D-link DI-614+ died, I've replaced it with a Linksys WRT54GL
> router. I had an external D-link AN24 antenna on my old router. The
> antenna has a cable with an N connector and a (reversed?) SMC connector
> and the latter one connected with the router.
>
> Now my new Linksys WRT54GL has a reversed TNC connector. Can I use my
> old external antenna after replacing the SMC connector with a TNC
> connector or are the antenna's with different types of connectors
> inherently different?


You should have no problem using that antenna on your new router as long as
you can get the correct adapters.
I can't remember off top if the 614 has two antennas or not but i know the
linksys does. You'll be better off if you have two of the same antennas.

Adair

Adair Witner wrote:
> "Sjeng" <sjengs2000@yahoo.com> wrote in message
>> Since my D-link DI-614+ died, I've replaced it with a Linksys WRT54GL
>> router. I had an external D-link AN24 antenna on my old router. The
>> antenna has a cable with an N connector and a (reversed?) SMC connector
>> and the latter one connected with the router.
>>
>> Now my new Linksys WRT54GL has a reversed TNC connector. Can I use my
>> old external antenna after replacing the SMC connector with a TNC
>> connector or are the antenna's with different types of connectors
>> inherently different?
>
>
> You should have no problem using that antenna on your new router as long as
> you can get the correct adapters.
> I can't remember off top if the 614 has two antennas or not but i know the
> linksys does. You'll be better off if you have two of the same antennas.
>
> Adair
>
>

I have an extension cable for the antenna with N-connectors, so finding
the appropriate N-female to rp-TNC connector is not a problem. I've seen
it in a webshop for 6 euros.

I had an ancient 614 with two antennas (newer models only have one). I
even have the idea that they had different functions. The old set-up was
actually a mess and the performance of the 614 a disaster. The WRT
performs far superior without an external antenna in signal quality then
the 614 ever did with or without an external antenna.

Regrettably I only have a single external antenna. Due to the thick
walls the supplier has installed it in our home; otherwise the range
would be very limited. However they never mentioned the advantage to
have two antennas.

It's just a in-house solution does it matter much that I only replace
one default antenna with an external one in a different room? Or is is
better to ditch the old external one and use the extension cable to
mount one of the default Linksys antennas in a different room?

Joel

On Fri, 08 Dec 2006 15:42:38 +0100, Sjeng <sjengs2000@yahoo.com> wrote
in <79557$457979dd$8978b1ad$15980@news2.tudelft.nl> :

>I had an ancient 614 with two antennas (newer models only have one). I
>even have the idea that they had different functions. The old set-up was
>actually a mess and the performance of the 614 a disaster. The WRT
>performs far superior without an external antenna in signal quality then
>the 614 ever did with or without an external antenna.
>
>Regrettably I only have a single external antenna. Due to the thick
>walls the supplier has installed it in our home; otherwise the range
>would be very limited. However they never mentioned the advantage to
>have two antennas.
>
>It's just a in-house solution does it matter much that I only replace
>one default antenna with an external one in a different room? Or is is
>better to ditch the old external one and use the extension cable to
>mount one of the default Linksys antennas in a different room?

You'd probably be better off replacing the Linksys with a router that
takes only one antenna; e.g., Buffalo WHR-HP-G54. Recommended.

--
Best regards, FAQ for Wireless Internet: <http://Wireless.wikia.com>
John Navas FAQ for Wi-Fi: <http://wireless.wikia.com/wiki/Wi-Fi>
Wi-Fi How To: <http://wireless.wikia.com/wiki/Wi-Fi_HowTo>
Fixes to Wi-Fi Problems: <http://wireless.wikia.com/wiki/Wi-Fi_Fixes>

John Navas <spamfilter0@navasgroup.com> hath wroth:

>You'd probably be better off replacing the Linksys with a router that
>takes only one antenna; e.g., Buffalo WHR-HP-G54. Recommended.

The WHR-HP-G54 has two antennas for diversity, one of which is an
internal PCB antenna at the top of the unit. See photo on the FCC web
pile at:
<https://gullfoss2.fcc.gov/prod/oet/forms/blobs/retrieve.cgi?attachment_id=569034&native_or_pdf=pd f>
It's the almost blank area between the push button and the external
antenna connector. The "extra" antenna can be disabled in firmware
(using DD-WRT) on both the Buffalo and Linksys devices.

[Hmmmm... I really don't like the LONG trace from the radio section
to the R-SMA connector on the WHR-HP-G54. G10 is rather lossy.]

--
Jeff Liebermann jeffl@comix.santa-cruz.ca.us
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

On Fri, 08 Dec 2006 10:42:10 -0800, Jeff Liebermann
<jeffl@comix.santa-cruz.ca.us> wrote in
<h2cjn2l5k1rdaklhrkevk2jk2oi0ccbl7s@4ax.com>:

>John Navas <spamfilter0@navasgroup.com> hath wroth:
>
>>You'd probably be better off replacing the Linksys with a router that
>>takes only one antenna; e.g., Buffalo WHR-HP-G54. Recommended.
>
>The WHR-HP-G54 has two antennas for diversity, one of which is an
>internal PCB antenna at the top of the unit. See photo on the FCC web
>pile at:
><https://gullfoss2.fcc.gov/prod/oet/forms/blobs/retrieve.cgi?attachment_id=569034&native_or_pdf=pd f>
>It's the almost blank area between the push button and the external
>antenna connector. The "extra" antenna can be disabled in firmware
>(using DD-WRT) on both the Buffalo and Linksys devices.
>
>[Hmmmm... I really don't like the LONG trace from the radio section
>to the R-SMA connector on the WHR-HP-G54. G10 is rather lossy.]

My understanding and experience is that the WHR-HP-G54 firmware favors
the external antenna. Otherwise, it wouldn't make sense for Buffalo to
sell higher-gain external antennas. ;)

--
Best regards, FAQ for Wireless Internet: <http://Wireless.wikia.com>
John Navas FAQ for Wi-Fi: <http://wireless.wikia.com/wiki/Wi-Fi>
Wi-Fi How To: <http://wireless.wikia.com/wiki/Wi-Fi_HowTo>
Fixes to Wi-Fi Problems: <http://wireless.wikia.com/wiki/Wi-Fi_Fixes>

On Fri, 08 Dec 2006 22:46:30 GMT, John Navas
<spamfilter0@navasgroup.com> wrote:

>On Fri, 08 Dec 2006 10:42:10 -0800, Jeff Liebermann
><jeffl@comix.santa-cruz.ca.us> wrote in
><h2cjn2l5k1rdaklhrkevk2jk2oi0ccbl7s@4ax.com>:
>
>>John Navas <spamfilter0@navasgroup.com> hath wroth:
>>
>>>You'd probably be better off replacing the Linksys with a router that
>>>takes only one antenna; e.g., Buffalo WHR-HP-G54. Recommended.
>>
>>The WHR-HP-G54 has two antennas for diversity, one of which is an
>>internal PCB antenna at the top of the unit. See photo on the FCC web
>>pile at:
>><https://gullfoss2.fcc.gov/prod/oet/forms/blobs/retrieve.cgi?attachment_id=569034&native_or_pdf=pd f>
>>It's the almost blank area between the push button and the external
>>antenna connector. The "extra" antenna can be disabled in firmware
>>(using DD-WRT) on both the Buffalo and Linksys devices.
>>
>>[Hmmmm... I really don't like the LONG trace from the radio section
>>to the R-SMA connector on the WHR-HP-G54. G10 is rather lossy.]
>
>My understanding and experience is that the WHR-HP-G54 firmware favors
>the external antenna. Otherwise, it wouldn't make sense for Buffalo to
>sell higher-gain external antennas. ;)

Buffalo could probably sell it without an external antenna as the
internal antenna PCB works well enough. For example, the Linksys
WRT54GC:
<http://www.linksys.com/servlet/Satellite?c=L_Product_C2&childpagename=US%2FLayout &cid=1115416825655&pagename=Linksys%2FCommon%2FVis itorWrapper>
has an internal PCB antenna, an R-SMA jack hidden under a hinged
panel, and is delivered with no external antenna (to save perhaps one
dollar). Works well enough, but adding an external antenna does help
the coverage considerably.

Another common question about the WRT54G antenna system is which
antenna is "left" and which is "right" in the setup. The answer is
that the designations are from viewing the back of the router.


--
# Jeff Liebermann 150 Felker St #D Santa Cruz CA 95060
# 831-336-2558 jeffl@comix.santa-cruz.ca.us
# http://802.11junk.com jeffl@cruzio.com
# http://www.LearnByDestroying.com AE6KS

Jeff Liebermann <jeffl@comix.santa-cruz.ca.us> hath wroth:

>Another common question about the WRT54G antenna system is which
>antenna is "left" and which is "right" in the setup. The answer is
>that the designations are from viewing the back of the router.

Oops. I got it backwards. WRT54G right and left are looking at the
*front* of the router. (So much for my photographic memory).

--
Jeff Liebermann jeffl@comix.santa-cruz.ca.us
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

Well thanks for the replies...
The point is that I haven't seen the Buffalo routers for sale in the
Netherlands and I've just bought the new WRT54GL...
The range of the new router is acceptable (not really good) as is, so
the point is: is it sensible to connect the one external antenna that
I've got (by replacing the connector), or is it better to stick with the
standard antenna's and forget about the old external one?

"Sjeng" <Sjengs2000@yahoo.com> wrote in message
> Well thanks for the replies...
> The point is that I haven't seen the Buffalo routers for sale in the
> Netherlands and I've just bought the new WRT54GL...
> The range of the new router is acceptable (not really good) as is, so
> the point is: is it sensible to connect the one external antenna that
> I've got (by replacing the connector), or is it better to stick with the
> standard antenna's and forget about the old external one?

If you have a GL put DD-WRT on it and you can play with which antennas do
you the best job..

Adair

On Sat, 09 Dec 2006 21:15:19 +0100, Sjeng <Sjengs2000@yahoo.com>
wrote:

>The point is that I haven't seen the Buffalo routers for sale in the
>Netherlands and I've just bought the new WRT54GL...

In my opinion, the radio section of the WRT54G/GS/GL are not so
wonderful. Adequate, but not great. I compensate somewhat by
cranking the tx power up from the default 35mw to about 100mw.

>The range of the new router is acceptable (not really good) as is, so
>the point is: is it sensible to connect the one external antenna that
>I've got (by replacing the connector), or is it better to stick with the
>standard antenna's and forget about the old external one?

Leave the WRT54GL unit alone and get an adapter between whatever
external antenna you currently have and the R-TNC on the WRT54GL. From
your original posting, you claim to have a DLink AN24 antenna. My
guess it's an ANT24-XXXX where XXXX is any one of 10 different models.
Could I trouble you to properly identify what you currently have?
However, it's not terribly important as all the DLink antennas use
R-SMA connectors. So, what you need is an R-SMA jack to R-TNC plug
adapter. This adapter usually comes with most replacement antennas,
but can be purchased on eBay:
<http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=170058455233>
<http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=270065479853>
Lots more. That should allow you to use whichever antenna you have
without butchering the WRT54GL.

--
# Jeff Liebermann 150 Felker St #D Santa Cruz CA 95060
# 831-336-2558 jeffl@comix.santa-cruz.ca.us
# http://802.11junk.com jeffl@cruzio.com
# http://www.LearnByDestroying.com AE6KS

At my mother's house, I had a spare 5 dbi omni on a short cable and
hooked it up to one side of her linksys WRT54G and got improved
reception. I left the other antenna in place. There is no choice
availible for antenna selection in the stock firmware for the Linksys.
Still, it seems to work it out more or less with it's diversity antenna
selection. Technically, I understand that it's not quite right this
way, but it worked.

It was just temporary to get reception in a distant room, while I was
visiting. But it made the difference.

Here in our community system, I've got a panel antenna hooked to one
side of a linksy WRT54G. Again, it's temporary. I will pull it soon
and put in a Buffalo router, but for now, the Linksys here is also
working fine with the stock antenna on one side and the 12 db antenna
(on a long low-loss cable) on the other. I got about a 6-10 db
improvement when I put the high-gain antenna on. Some of that is from
better positioning with a remote antenna.

So yes, you can do it with one antenna on the Linksys and it will work.
Two matching antennas are not needed. Still, to make it work
correctly with one, I understand that it's best to turn off the other
antenna. To do this, you need to install a different firmware (DD-WRT
for example) on the linksys that allows for antenna selection. Then
you can turn the weak antenna off so the radio does not "see" it.

I read somewhere that you still want to leave the "dead" stock antenna
connected in order to "terminate" the line or "balance the load", or
some such thing.

Steve

Actually, hearing from Jeff that the Buffalo also has a second antenna
and, I presume, a diversity system, it makes me wonder.

When Buffalo sells you a single higher gain antenna for their router,
are you supposed to turn off the internal?

Or does it matter much? I'm guessing that they don't expect you to know
or do anything about the hidden internal. And I can't remember if
their stock firmware has an antenna managment section.

Steve

"seaweedsteve" <seaweedsteve@gmail.com> hath wroth:

> I read somewhere that you still want to leave the "dead" stock antenna
>connected in order to "terminate" the line or "balance the load", or
>some such thing.

If you disable one antenna in the firmware, it doesn't matter what you
do with the unused antenna port. It does nothing, goes nowhere, has
no effect. No need to terminate it.

If you do NOT disable the unused antenna port, there's a small chance
that diversity reception will select the wrong antenna. See the golf
course case study at:
<http://www.cisco.com/en/US/tech/tk722/tk809/technologies_tech_note09186a008019f646.shtml#cases tudy>

--
Jeff Liebermann jeffl@comix.santa-cruz.ca.us
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

"seaweedsteve" <seaweedsteve@gmail.com> hath wroth:

>Actually, hearing from Jeff that the Buffalo also has a second antenna
>and, I presume, a diversity system, it makes me wonder.
>
>When Buffalo sells you a single higher gain antenna for their router,
>are you supposed to turn off the internal?

Good question with no simple answer. My guess(tm) is that the
internal antenna should theoretically be disabled, but if it's left
enabled, it doesn't do much good for diversity.

Diversity reception works to help solve frequency selective fading.
That's where you have two paths from the xmitter to one of the receive
antennas that are 180 degrees out of phase, resulting in cancellation.
That usually happens only in a highly reflective environment as
commonly found indoors. Outdoors, there are fewer opportunities for
reflections and multipath.

Diversity reception works best if the antennas have roughly identical
patterns and roughly identical gains. That's a fair approximation of
the Buffalo router, with it's internal PCB antenna with about 2dBi
gain, and a short coaxial external antenna with the same gain. No
problems. However, if we replace the external 2dBi rubber ducky
antenna with perhaps an 8dBi panel antenna, the patterns and gains
become radically different. Diversity reception fails as per the
previous mentioned golf course example, especially when the client is
moving in and out of the pattern.

If the external antenna ends up on a rooftop, but the internal antenna
is still functional, then there's a *SMALL* possibility that the
client will connect to the wrong antenna and end up with rather rotten
connection. It will persist until the AP firmware declares the
connection to be useless and switches to the other antenna. It can
happen, I've seen it happen, but I guess(tm) that it's not a big deal
and should not precipitate a mass reconfiguration of everyone's access
point.

>Or does it matter much? I'm guessing that they don't expect you to know
>or do anything about the hidden internal. And I can't remember if
>their stock firmware has an antenna managment section.

My two Buffalo routers have DD-WRT firmware so I can't check.

--
Jeff Liebermann jeffl@comix.santa-cruz.ca.us
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558