Adding an Antenna to a Underpowered Router

I have a D-Link router of the 2.4 gHz type. It supports 802.11b and I use it for all of the laptops I repair and test. I occasionally want to push the signal to the other end of the house, and I chose to do this, rather than buy a new add-on antenna.
Recycle, man...Recycle.

Step 1: Getting Started...

I chose to keep the D-Link and cannibalize the Linksys for two reason, the first being that the Linksys uses a weird propietary 50-pin header to connect the card to the motherboard of the router. The second is that the D-Link uses a mini-PCI card as the receiver. I have a future use also, and this will make an upgrade easier, by far.
I also note the mini-PCI actually HAS two antenna inputs soldered on the card. The second one terminates in a little strip of metal that is stuck to the inner side of the case with double-back tape.

Step 2: Proof of Concept...

This is a photo meant to help actualize the concept we are attempting. I just soldered the end of the antenna to the mini-PCI card, leaving almost the length of the second lead intact. I energized the router out of it's plastic shell, and according to the Cisco tables, a -30 dBm gain in strength. I have measured the signal strength in a before and after walk-around and the signal AFTER is well worth the time to do this mod. I see gains incidental of location (on my property) and an overall signal strength increase
of 225%. (from 4 dB to 7 B for the second antenna.)

Step 3: Adding the Antenna...

Here we just cut the donor antenna lead.

Step 4: Removing the Second Pigtail Lead...

isolate and remove the second pigtail lead...

Step 5: Stripping...and Attaching

Strip, tin and prepare the donor antenna lead. Clean with alcohol and either heat lamp or can-dry to remove moisture.

Step 6: Attaching the Second Lead...

Use alcohol and a toothbrush for pre-cleaning, dry with heat lamp, and then solder the leads to the perspective places. Shield to outside, center lead to center space.
You will want to check for continuity and solder flow.

Step 7: Plastic Shell

Remove the motherboard from the plastic shell and mark on tape a circle of the approx. size the antenna end requires. I used a plastic washer to mark the I.D. of the circle, and a drill bit to SCORE
the outside edge. I did NOT just drill into the case, I stopped the drill bit shy of cutting through to better control breakthrough of the thin plastic. I used a center pin drill with a cutting edge to best effect.

Step 8: Hole Drilled...

I cut the remainder of the hole with a sharp X-Acto knife. This is TERRIFICALLY thin plastic, very fragile.

Step 9: Check for Interference...

The motherbord should now be placed back as well as the new antenna to check for interference. The photo shows the fiberglass motherboard was trimmed with a file to accommodate the new antenna.

Step 10: Finishing Up...

1) Replace motherboard in shell 2) Replace mini-PCI card in motherboard 3) Lead Dress

Step 11: Ready to Use...

Plug it in...and enjoy 7 dB around the house. I hope anybody else who does these steps has the same result as I. Your mileage will vary, some features not available in all localities... : )