Modding the WRTSL54GS

Work was a mess this week, due to an office move and other issues, so I've fallen a bit behind on where I wanted to be on the wireless project. I finally got some time to work on the project late this week. After a run down to the local Fry's, I had all the parts I needed to modify the main board on the WRTSL54GS. I dove into this the other night and found that I was in for more trouble than I expected. First, I pulled out my practice PCB and started soldering again, trying to get warmed up before working on some of the more important parts of the project. Next, I assembled the RS232 adapter and managed to avoid botching the soldering. That made me feel pretty good, so I pressed on... and started wrecking some parts.

The WRTSL54GS uses a very poor antenna in its stock form. It is rated at 1.5 dBi gain, which did not fill me with enthusiasm. So I decided to replace it, but I have a problem The antenna is connected directly to the main board with no way to detach the stock antenna cleanly. Since I was feeling brave after successfully soldering the RS232 adapter, I pulled out the wire cutters and clipped the antenna wire close to the antenna. I wasn't quite brave enough to attempt soldering a new antenna smack in the middle of the board. I had picked up two SMA connectors at Fry's, which I figured would be sufficient. When I attempted to crimp the center pin to the coax cable, I damaged both of them. They would not even come close to sliding up the center of the adapter. Now what? Today, I did another run to Fry's and purchased three more connectors. When I got home, I found that I had the wrong models. The center pins were hollow and I needed the solid ones. So, I needed to salvage the pins I had from the previous night. A bit of dremeling cleaned up one the center pins enough to be usable. Instead of crimping, I soldered the pin to the antenna wire, crimped on the outside of the connector and it all looked pretty good.

Next, I started hooking up the connector to the serial ports on the main board. This sounds straight forward, but Linksys decided to make it more complex. They filled the holes with solder. *sigh* After 30 minutes of messing around the holes were cleared out and I was able to solder in the new head block.

I was a bit nervous again about this because I had to apply a fair bit of heat to get the solder out. I took it up stairs, attached a 10 dBi gain antenna and booted up the router. Sure enough, it booted up cleanly! Needless to say, I'm very happy with this. But was the new antenna working? Fortunately it was. Here's a screen cap of the signal strength.



The SSID of Elune is my access point and WRT is my newly modded router. Both Linksys SSIDs are neighbors, one of which is inviting trouble. Any how, I was on the other side of the house when this cap was taken. Note the huge difference in signal strength of WRT using the new antenna when compared to Elune! Both devices were sitting right next to each other. Mission accomplished.

Here's the modded main board.