So, I went to add an external connector to my notebook last night for bluetooth and/or for wifi. I had it almost totally taken apart in order to see where I wanted to mount my SMA connector.
Well, I finally figured out where to mount it (perfect spot by the way), and then I went to solder the wire to the connector itself. I realized I didn’t know exactly where the ground wire was supposed to go. The whole thing was metal, if my case was metal the ground of the antenna would be grounded to case, unless I insulated the base from the case. (my sma connector had holes to bolt it to whatever)
That didn’t sound right to me so I took apart my screen so I could look at the internal antennas, and from what i could see, both ends of the wire solder to each end of a piece of metal, which acts as the antenna. I measured the resistance at the other end of the cable where you would attach it to the card, and it shows, I think .7 ohms. All 3 internal antennas where the same resistance and looked identical, just one after another on top of my screen.
So, I decided I was going to solder the outside wire shield of the coax I got to the casing of the SMA connector, but I couldint really see a good way of soldering it where the middle wire couldin’t possibly ground itself out if the wiregot moved. It also appeared that the middle wire thing coming out of the connector was created to stick inside the insulation part of the middle wire in the coax, but the coax I bought was too small to do that.
What is the proper way to solder the coax cable to a SMA connector? Both ends (female and male) I take it most of you have experience with solder to pcb type connectors.
Also, I bought a set of new wifi antenna’s from radio shack, they were on clearance for 5.00 for both. From what I googled it they should work for blue tooth, both are 50ohm specs and operate in the 2.4ghz spectrum. Well I went to measure the resistance of the antenna’s and I got 0.0. In otherwords, the outside metal part of the connector was not in anyway connected to the middle wire. I took it apart (but had to destroy it, oh well, good learning experience) and I couldin’t see how they could have ever been connected. I also measured from the bottom of the inside whip part to the top and got .7 ohms, same as the ones in my notebook. But there was no way that a wire connected to it could ever see .7 ohms since the ground was not connected to the top of the whip, if that is in fact how it’s supposed to work.
Can anyone give me the run down on wireless antenna’s and how they are supposed to function electrically? I googled the best I could, but I couldin’t find anything that really explained it well.
Thanks much!