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Transmitter hunting was my favorite hobby in the late 70s. My wife and I did a lot of that when we were dating. The guys with yagis were rapidly eclipsed by people with Doppler DF equipment. I built a real good unit based on the DopScan kit. It used 8 antennas arranged in a 30 inch circle. The antennas were enabled sequentially around the circle. The produced a virtual "spin" of a single antenna around the circle. The apparent motion created a Doppler offset against an incoming radio signal. The spin rate was around 400 Hz, thus creating a 400 Hz tone in an FM receiver (the Doppler was essentially frequency modulating the incoming carrier). A switched capacitor filter operated by the same clock that runs the antenna provided a narrow 1 Hz wide audio filter. The output of that stage was a sine wave at the clock frequency. The negative slope, zero cross of the sine wave occurred when the selected antenna was closest to the incoming wave front. Accuracy was +/- 22.5 degrees. The relative direction of the signal was displayed on a 16 LED display. The Doppler technique is fairly insensitive to signal strength.

The transmitter hunt was conducted by having all participants gather at the starting point. Odometer readings were recorded. At 5 PM the transmitter is switched on. When the participant finds the transmitter, the time is recorded and mileage is recorded. The sum of miles and minutes is your score. Low score wins. Using the DoppleScAnt, you can get to the transmitter as rapidly as driving conditions permit. Do a Google search for DoppleScAnt to see PDF drawing of the designs.

If you want to get better results on your 2.4 GHz bridge, I recommend using an Ethernet Bridge with Power Over Ethernet to put the transmitter as close to the antenna as possible. Minimize the coax losses with very short runs or select LMR400 with type-N connectors to reduce the losses. I purchase most of my 2.4 GHz "toys" from Hyperlink Technologies. If you have a small order, they have an e-Bay shop. They sell 2.4 GHz inline, pole mounted amplifiers. You'll need to make sure the amplifier is just overcoming the coax loss so your effective radiated power doesn't exceed FCC limits. The amps are available in bi-directional models. Remember than an amplifier amplifies signal and noise. You're ahead to get the Ethernet converter closer to the antenna in preference to a long coax run.

Look for a book called "WiFi Toys" at the bookstore. There are some fun projects in there.