"robert casey" wrote in message
link.net...
For some strange reason, wifi connectors are not compatible with normal
SMA coax connectors. The center pin is a male in an otherwise female
connector. And visa versa.

But you probably have accumulated a few wifi "rubber duck" antennas.
Inside the plastic "duck" is just some thin teflon coax cable and a dipole
antenna with a 1/4 wave shroud around the coax and 1/4 wave exposed center
conductor. It's easy to separate the plastic duck off the antenna, just
bend it at the joint just above the elbow and it should just pop off.
Being teflon, you don't have to worry about melting it with the soldering
iron. This coax looks to be 50 ohm impedance. Get a BNC connector and
attach it like you would to coax of this thin type. To deal with the
extra thin coax, I used a small solderable metal washer to give the shield
clamping connector pieces (the funny looking washers) something to grab
when you tighten the threaded on the outside bushing you tighten into the
connector. As the connectors I had were meant for fatter coax. Don't
forget to place the washers and such on the coax before you solder the
washer to the coax shield.

As a test, I inserted two such adapters into the feedline for my wifi
antenna, and looked at the wifi utility software window that reports
signal strength, and saw no desernable extra signal loss (less than a dB).
(I scrapped out a bad wifi booster module to get its reverse SMA
connectors to get the mate for the antenna side connector)

Once you have built this adapter, you can then use regular good quality
coax cable with BNC connectors (or N or other connector good for microwave
work) to connect a homebrew wifi antenna to the wifi computer card.
There's also a ham band that shares part of the wifi band, so we could
conceivably run high gain high power ham to ham using wifi based
equipment.

Hi Robert

I'd like to know more about how well your extended range WiFi performs.
What type of antenna seems to be the most effective?
Why did you decide to not use a reverse SMA adapter like ShowMeCables
sells for about $5.00?
How do you measure "signal loss" to within a dB?

Jerry