View Full Version : Cable on Dlink cards
bairdc
12-05-2003, 12:56 PM
Sorry if this has been asked already. After searching the archives, I can't seem to find the answer. I'm just wondering what type of cable is used on the Dlink atheros-based cards? More specifically, what N connector will fit it? LMR-100?
Craig
georgew
12-05-2003, 06:34 PM
The cards with the detachable antenna use a reverse polarity SMA connector. You can get lmr400 reverse SMA connectors at www.fab-corp.com. Of course you can also get lmr100 connectors, as well as connectors for most other coax types.
But no, it's not an N connector... the N connectors are the large full-size connectors you see on most antennas.
The dlink cards that operate at 5ghz appear to have two different connectors used, one for the a only cards, and another for the ab cards. But I can't find any specific information, and I don't have one to take apart to look at.
bairdc
12-05-2003, 11:21 PM
I think maybe I didn't word my question very well.
Basically, I'm looking at getting a Dlink DWL-AG520 card. From what I can tell, these cards come with a chunk of coax that protrudes from the card, and there is an antenna attached to that cable. However, the problem is that the antenna is not detachable from the coax, meaning that in order to use an external antenna, you'd have to cut the included antenna off of the coax, and put some kind of connector on it.
Anyway, my question is, if I were to chop off the included antenna, and put an N connector on the included coax, what kind of coax is it, so I can get the appropriate N connector? Is it LMR-100 or something else?
Craig
georgew
12-06-2003, 12:06 AM
Ahh! Now I understand why you said lmr100 N connectors...
You might have to cut the cable and see how the measurements compare to some lmr100... lmr is a brand designation, and there are similar sized cables from other companies that have rg or other part numbers. I would guess that the cable is probably marked with it's type, and you should be able to cross reference a connector for it using google searches.
rg174 and rg316 connectors work well for me on lmr-100 and are much easier to find.
try RF industries part# RFN-1005-B-03 is describes as for "RG-174, RG-188, RG-316, and LMR-100". That's assuming the cable is lmr-100 sized. Tessco part #47312 http://www.tessco.com/products/inv_display.jsp?gsg=41030&selsku=47312&cs=1 Hopefully that link will work for you.
olebno
12-06-2003, 05:44 AM
Hi!
The text on the antenna cable on my DWL-AB520 states the cable is RG-316 and the cable on the DWL-AG520 does not have any text printed on it, but it looks like it have the same diameter as the cable on the AB520 card.
Hope that helps
Best Regards
Oleb
bobbyc
12-08-2003, 12:27 PM
Since I don't have the tiny N-connectors, will I be able to take a orinoco N-male pigtail, cut off the propreitary small connector, and solder the pigtail to a DWL AG520 card?
Thanks,
Bob C
jlawrence
12-08-2003, 12:45 PM
Don't see why not. At the end of the day, so long as you can get at a suitable point on the board you can solder anything to it. It doesn't make it very easy to upgrade/change the board in case of failure though.
bobbyc
12-08-2003, 05:30 PM
Actually I just got back from compUSA and picked up 3 AG520 cards. They have MMCX connectors on the board, I just unplugged the stock antenna and sure enough it looks like a MMCX connector, which I have plenty of pigtails for.
Time to bench test this puppy; I also bought a new "ciscoized" WET11, which has a agere chipset in it. I'm gonna test that too. Busy evening.
Bob C
go.fast
12-08-2003, 06:34 PM
Were you able to unplug the pigtail from the board without the hub falling off the board?
Can you try it a couple times and see if it doesn't fall off fir sure.
I'd like to try those cards again. But mine fell apart when I went to unplug the pigtail.
George
bobbyc
12-08-2003, 06:43 PM
I just realized how weak it is. So far so good though i think.
Bob C
bobbyc
12-09-2003, 06:33 PM
Ok it finally broke off the board.
I'm going to drop it off at a friends house and see if he can solder a pigtail directly to the board and then throw some silicone over it for strength... and then ziptie or heatshrink the pigtail to that little metal tab on the pci card itself that the origional pigtail was attatched to.
Bob C
go.fast
12-09-2003, 09:20 PM
Thats what happened to me...Twice. First to see what would happen second time to confirm.( duh)
Oh well there went my first atheros star-os link.
Rather than fool with it again I''m just gonna cut off the antena and ad an n female, if I can figure out the part number that matches that cable.
George
David L. Vrablic
12-09-2003, 10:02 PM
Yep George, looks like we are all on the same page.
I bought two of the AG520 cards this afternoon for my first dive into the Athros waters.
I was pleased to see the 174 type cable.
Now all I need is a source for a "Bulkhead N/F" connector.
I will be able to retro any of my existing sites with a card swap and a FW upgrade.
I havn't checked to far yet but is that a dual mode antenna that comes with the origional package?
georgew
12-10-2003, 12:24 AM
I got my bulkhead N females from www.fab-corp.com.
David L. Vrablic
12-10-2003, 08:03 AM
Thanks GW,
I'll order some out today.
Can wait to get the test going.
bobbyc
12-11-2003, 01:24 PM
http://www.sonnet.com/bob/wireless/DSCF0068.JPG
We soldered the pigtail to the cards, put heatshrink around the pigtail/metal tab on the outside of the card, and then put a ziptie around that. It is real secure now.
It's a good think I bought 3 cards, because the 3rd card (which was supposed to be a backup card) we lifted the solder off the board accidently.
Do you think we'd get equal signal levels if we used the 2nd antenna connector lead on the side of the original?
Bob C
David L. Vrablic
12-11-2003, 01:59 PM
Don't really know as these type of connections are most likely controlled by the firmware.
It was most likely set up with diversity or a "best signal" switching arrangement in mind.
It might be neat to temp a second pigtail to the other port and swap the antenna to each in turn then use two antennas and watch the sig meter to see what happens.
That could give a clue as to it being hooked up at all.
georgew
12-11-2003, 05:41 PM
Your pigtail is not going to have a 50 ohm connection, so you are going to have a lot of loss at the radio, and it will interfere with other radios in the box.
The unshielded section needs to be as short as possible, a millimeter or two.
Take an exacto and scrape a pad in the ground plane as close as possible to the signal point. Using low-temp solder, tin the shield without folding it back, so that the shield is almost flush with where you strip the center conductor. Solder a short center conductor to the signal point, then solder the braid to the clean ground plane you prepared. You don't want more than a couple millimeters of unshielded coax, otherwise most of the signal won't get into the coax.
At 2.4ghz you are probably loosing 20 to 30% of the signal... at 5ghz it would loose about half with that much unshielded conductor.
You will notice the board traces carrying the signal will have a ground plane below and around them, always in close. As soon as there is any distance between them, the losses increase.