Dumb question about Mini PCI cards

Looking at one of these cards there are two ports where you would plug in your antenna wires. My question is does it matter how they are hooked? You have a black wire and a white or red wire. Do the cards have some sort of polarity where it won't pick up signals if hooked up wrong? Also, would it make a difference if only one of the two wires were hooked up.

My Specs NEC Versa LitePad With Windows Tablet PC and SP/2 UGJZ 11a/b MIni PCI card

I am also thinking about getting a different card then this for my wireless needs. So Any suggestions as far as that goes would also be appreciated. Thanks in advance!

Reply to
OrionM31
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I think the two connections are like diversity antennas on wireless routers, where the device chooses the strongest signal.

It doesn't matter. My computer only has one antenna, and I have to connect it to the aux point because it won't reach the main spot. Works fine.

Reply to
Jerry Park
[POSTED TO alt.internet.wireless - REPLY ON USENET PLEASE]

One connector is for the Main antenna. The other is for the Aux (auxiliary) antenna. They should be marked on the card. The antenna cables should also be marked.

You should get best results with both antennas, due to "diversity." See

* *

If you only have one antenna, connect it to Main if possible, although it may work fine on Aux (depending on the particular Mini PCI product).

Be sure to make good antenna connections -- I've seen a number of cases of "Wi-Fi not working!" simply because the antenna connector came off.

Reply to
John Navas

Thanks! I will give wiki a look later. The Card that is in this Tablet PC didn't apear to have any labels on or near the plugs. I will take a closer look and post my findings later.

Reply to
OrionM31

Usually doesn't matter which antenna cable goes to which connector. Diversity reception is symmertical.

However, there's a possible catch. Some cards only transmit on one antenna. If the antennas at the ends of the black and white cable are roughly identical, it can go either way. However, if one is positioned horizontally, while the other vertically, you will probably want to connect the vertically polarized antenna to the "main" port. I don't recognize the NEC Versa card so I can't tell if this card works this way.

The easiest test is to try one MiniPCI port at a time. If one cantenna to board connection works fine, but the other acts like the card is sick, then the xmitter is only connected to the first port. However, if both ports work just fine, it transmits on both ports.

Reply to
Jeff Liebermann

That short stubby red wire is most likely the antenna itself. A quarter wavelength at 2.4GHz is about 1.2 inches.

David

Reply to
David
[POSTED TO alt.internet.wireless - REPLY ON USENET PLEASE]

Wouldn't have good gain. Perhaps it's a (shorter range) Bluetooth antenna, rather than a (longer range) Wi-Fi antenna.

Reply to
John Navas

" snipped-for-privacy@gmail.com" hath wroth:

That's common for diversity installations. The metal bulk of the LCD display tends to block signals in some directions. So, the manufacturers install the main antenna (black cable) in the LCD section. The aux antenna (red cable) is in the base unit. This separation should give the radio a better chance of picking up a signal from any direction.

Now we get complicated. The diversity algorithm methinks is used by the radio may have a bias toward reverting to the main antenna connector if the signal gets lost. What little reverse engineering I've done seems to show that the radios do NOT scan back and forth between antennas trying to find the best signal. It tends to sit on the main antenna and only switch antennas if it gets valid data with a high error rate. I really don't understand the logic, but that's what I'm seeing. Therefore, if your MiniPCI card works this way, it would tend to favor the main antenna port, which should therefore be connected to the better (black cable) antenna.

Just to drive everyone insane, the antennas ports are often labeled in the setup software as "right" and "left" instead of "main" and "aux" or "primary" and "secondary". I note that Cisco corrected this mistake several years ago, but the low cost vendors apparently still don't know their right from their left.

The tiny u-FL connectors are good for only a few insertion/removal cycles. Be VERY careful or they will break. It can also be a driver issue. Installing multiple network drivers from different vendors is not a great idea. I had a test laptop where I had installed about 10 different drivers for various cards I was using. At no time could I get more than a few of them to work at the same time. I eventually had to resort to using Windoze Profiles and Netswitcher to switch configurations. Unfortunately, I didn't track which driver stomped on which other driver.

Yes, there's a difference per previous discussion. However, that has nothing to do with your current problem. Even if the antennas were totally disconnected, the board leaks enough RF that you can make a connection to a wireless access point from a few feet away. If you can't make a connection at all, or see any other SSID's, then it's not the antennas and something else is wrong.

Hint: Kindly disclose what problem you're trying solve when asking a question. It makes the answer somewhat more relevant.

Reply to
Jeff Liebermann

On 2 Jun 2006 08:23:03 -0700, " snipped-for-privacy@gmail.com" wrote: : Looking at one of these cards there are two ports where you would plug : in your antenna wires. My question is does it matter how they are : hooked? You have a black wire and a white or red wire. Do the cards : have some sort of polarity where it won't pick up signals if hooked up : wrong? Also, would it make a difference if only one of the two wires : were hooked up. : : My Specs : NEC Versa LitePad With Windows Tablet PC and SP/2 : UGJZ 11a/b MIni PCI card : : I am also thinking about getting a different card then this for my : wireless needs. So Any suggestions as far as that goes would also be : appreciated. Thanks in advance!

Dell's instructions tell you to connect the white wire to the main terminal and the black wire to the auxiliary terminal. But in every Dell laptop I've ever opened, both wires are black.

Reply to
Robert Coe
[POSTED TO alt.internet.wireless - REPLY ON USENET PLEASE]

Doesn't seem to fit the available facts:

  • "Little stubby wire that is only about two inches long" (red) would make for a poor Wi-Fi antenna.

  • SOP in the better quality notebook computers I've examined is to have both antennas in the LCD cover, one at each vertical edge, which would seem to be better in most cases than having a horizontal antenna in the base.

Reply to
John Navas
[POSTED TO alt.internet.wireless - REPLY ON USENET PLEASE]

No identifying color on just the connector?

Reply to
John Navas

John Navas hath wroth:

I beg to differ with your available facts.

I have seen some that are far smaller than that. One Toshiba laptop had two small PCB antennas mounted on the lower part of the hinge assembly. I took some photos but can't find them. Note the size of the actual antenna element: |

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the photo. I frequently make such coaxial antennas by simply peeling back the braid, cutting it to length, and embalming the antenna in shrink tube. Works fine.

Incidentally, 1/4 wavelength at 2.4GHz is 3.13cm long, which would make a decent antenna. Add a counterpoise (ground) and you have a coaxial antenna as found in most rubber ducky antennas. See: |

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think that antenna came with a DI-514 before I destroyed it.

Yep. See: |

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|
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how it's done in an IBM T40 and T23 laptop. Unfortunatly, many laptops simply don't have enough room in the hinge area to handle a total of 3 coax cables. I've done 2 repairs so far on Toshiba lapops that have had the coax cable crunched or cut by the hinge. Most of these antenna installation are retrofits by the manufacturer.

In some cases, the diversity is rather minimal, as in this combined antenna: |

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Note the length of the coax cables on this pair of antennas: |
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interesting data on dual band antennas. Looks like the average gain at 2.4GHz is about -2.5dB for the various types.

Incidentally, I looked at every MiniPCI wireless card I had in stock or handy and found that they all had a "main" and "aux" label on the connectors.

Reply to
Jeff Liebermann
[POSTED TO alt.internet.wireless - REPLY ON USENET PLEASE]

Again, this is just a "little stubby WIRE that is only about two inches long." [emphasis added] Commercial 2.4 GHz antennas are generally easy to distinguish from plain wiring, as shown in the pictures you linked.

Exploded view of ThinkPad T30 LCD showing size and locations of dual Wi-Fi antennas (part #4):

That's a single antenna. Read Features.

Me too.

Reply to
John Navas

Look again at the photos and count the cables. That's two antennas, with a common ground connection, and two coax cables. Allegedly, the antennas are sufficiently seperated by being at right angles to each other, to provide some level of diversity. I'm suspicious but I do recall the reading IEEE Ant and Prop proceedings where some tests were run demonstrating that such a contrivance really does work tolerably well.

Reply to
Jeff Liebermann

On Mon, 05 Jun 2006 14:27:09 GMT, John Navas wrote: : [POSTED TO alt.internet.wireless - REPLY ON USENET PLEASE] : : In on Sun, 04 Jun 2006 19:12:29 : -0400, Robert Coe wrote: : : >On 2 Jun 2006 08:23:03 -0700, " snipped-for-privacy@gmail.com" wrote: : >: Looking at one of these cards there are two ports where you would plug : >: in your antenna wires. My question is does it matter how they are : >: hooked? You have a black wire and a white or red wire. Do the cards : >: have some sort of polarity where it won't pick up signals if hooked up : >: wrong? Also, would it make a difference if only one of the two wires : >: were hooked up. : >: : >: My Specs : >: NEC Versa LitePad With Windows Tablet PC and SP/2 : >: UGJZ 11a/b MIni PCI card : >: : >: I am also thinking about getting a different card then this for my : >: wireless needs. So Any suggestions as far as that goes would also be : >: appreciated. Thanks in advance! : >

: >Dell's instructions tell you to connect the white wire to the main terminal : >and the black wire to the auxiliary terminal. But in every Dell laptop I've : >ever opened, both wires are black. : : No identifying color on just the connector?

Not that I remember seeing. So what I typically do is connect each wire to its nearest connector on the card. Seems to work OK.

Reply to
Robert Coe

OK -- I first thought that was a shadow or reflection.

Perhaps, but I'm skeptical.

Reply to
John Navas

Sorry it took me so long to find out by switching these cables around it would fix the issue because that is exactly what I did and now I can see the two open wireless points in my neighborhood/ :) Although I am only getting one bar. I had decided to go for a Broadcom Mini PCI card to replace the one that I have in the NEC Laptop I have. Once I reopen it, I will post some pictures of the card so you can see for yourselves that I didn't see any marking on this card. It could be that it was a first gen card and since there is no access panel to easily get to the card to replace it that it was never thought that someone would change it. :) It is quite a hassle to tear the Tablet apart just to get to the card since it is on the backside of the unit. That means that everything has to be pulled out in order to change the card. UGH! I have tore this silly thing apart so much that it I could do it in my sleep practically. Thanks for all your help everyone!

Phil

Reply to
OrionM31

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