How to Build a Low-Cost DIY WiFi Repeater and Signal Booster With Spare Router Parts

Introduction

Having weak WiFi signal in parts of your home can be frustrating. While you can buy commercial WiFi extenders, they can be expensive. Luckily, with a bit of DIY spirit, you can build your own WiFi repeater and signal booster using spare router parts for a fraction of the cost.

In this guide, I'll walk you through the complete process of building a DIY WiFi repeater and signal booster using an old router. This project requires some technical skills, but if you follow the steps closely, you can create your own affordable solution to improve WiFi coverage in your home.

What You'll Need

To build the DIY WiFi repeater and signal booster, you'll need the following:

Spare wireless router - This serves as the heart of the repeater. Look for a dual-band router for wider compatibility.
DD-WRT compatible router - DD-WRT is custom firmware that lets you configure a router as a repeater. Check their router database for compatibility.
Ethernet cable - To connect the main router and repeater router. You'll need long enough cable to run between the two locations.
Tools - Basic tools like screwdrivers, pliers, etc. to take apart the router case.
Drill - If you need to mount the router in a high location.

How It Works

A WiFi repeater takes an existing WiFi signal, amplifies it, and rebroadcasts it to extend the range. Here's a quick rundown of how our DIY repeater will work:

It will connect to your existing WiFi network wirelessly to grab the signal.
It will amplify and rebroadcast the signal with the same SSID and password.
Clients will automatically connect to the stronger repeater signal as they move out of range from the main router.

Flashing the Router with DD-WRT Firmware

The first step is to install DD-WRT custom firmware on the spare router you'll use as the repeater. Here are the steps:

Download the correct DD-WRT firmware for your router model from the DD-WRT website.
Connect your computer directly to the repeater router via Ethernet cable.
Access the router admin interface in your web browser (192.168.1.1 typically).
Navigate to the firmware upgrade section and upload the DD-WRT firmware file.
Let the router reboot and upgrade. This takes 5-10 minutes usually.
Log back into the router admin interface once upgrade is complete.

Configuring the Repeater in DD-WRT

Once DD-WRT firmware is installed, we need to configure the router to function as a repeater:

In the setup tab, go to the Basic Setup section.
Set the router mode to "Repeater".
Enter your main router SSID as the wireless network name.
Choose WPA2 encryption and enter your WiFi password.
Select the repeater bridged mode option.
Disable DHCP server and NAT to avoid conflicts.
Set the IP address to something outside your main router's DHCP range.
Click Save and Apply Settings.

Connecting the Main Router and Repeater

For optimal performance, it's best to connect the main router and repeater with Ethernet:

Run Ethernet cable between your main router location and repeater location.
Connect one end to a LAN port on your main router.
Connect the other end to one of the LAN ports on the repeater router.
This provides backhaul connectivity for maximum throughput.

Positioning the Repeater

Positioning is crucial - you want to place the repeater where it can receive a decent signal from the main router but also sufficiently extend coverage:

Try halfway between the main router and weak coverage area.
Elevation helps - place it as high as possible, like on top of a shelf or mounted to a wall or ceiling.
Avoid obstacles like thick walls, metal objects, pipes, etc. that can degrade WiFi signals.
Fine tune position by checking repeater signal strength in admin interface as you move it around.

Testing and Optimizing Performance

Once it's all set up, test the DIY repeater and make any needed optimizations:

Walk around with a mobile device to check extended WiFi range.
Use a WiFi analyzer app to check signal strength and identify dead zones.
Switch channels on 2.4GHz band if needed to reduce interference.
Enable WMM for better connectivity with multiple clients.
Reboot router and clients if you face any weird issues.

Wrapping Up

That covers the complete process of constructing your own DIY WiFi repeater and signal booster with an old router and DD-WRT firmware. While it requires some technical skill, it's a fun project that can extend your home WiFi coverage on the cheap. With proper positioning and optimizations, you can get performance that rivals commercial WiFi range extenders. Enjoy the satisfaction of tackling your connectivity issues with DIY ingenuity!