The One Thing Most People Miss in Playback

When people first review their overnight playback, the natural instinct is to focus on where the most activity is. That makes sense — a sensor that triggered 47 times feels important. And it is. But it's not the most useful data point.

The most useful data points are the first movement of the night and the last movement before morning.

That's because those two moments tell you something the busy sensors can't: direction of travel. The first trigger shows you where the rodent is coming from. The last trigger shows you where it's going back to. Between those two bookends, you have your trail — and at one end of that trail is either a nest or an entry point.

What the First and Last Movements Reveal

First Movement = Where They're Coming From

The first sensor to trigger each night tells you the direction the rodent is emerging from. They're either leaving a nest inside your home, or entering through an exterior gap or crack. Either way, that first trigger points you toward the source.

Last Movement = Where They're Going Back

The last sensor to trigger before activity stops tells you where the rodent retreats to. In many cases, the first and last movements point in the same direction — toward the same entry point or nest. That convergence is what narrows down the search.

The sensors that fire in between? Those show you their routes — where they travel, where they feed, which rooms they're using. That's valuable context. But the endpoints are what solve the problem.

Setting the Right Monitoring Window

From your dashboard, you can set the monitoring window for each device — the hours during which sensor activity is recorded and displayed in playback. This is more important than most people realize.

Example Scenario

Catching the True First Movement

Let's say you set your monitoring window from 9:00 PM to 6:00 AM. You review the morning playback and see:

9:05 PM Sensor 4 triggers — first event of the night
9:22 PM Sensor 2 triggers
9:41 PM Sensor 6 triggers

The problem: Sensor 4 triggered at 9:05 PM — just 5 minutes after your window opened. Did the rodent emerge at 9:05, or was it already active at 8:45 and you missed the real first movement?

When the first trigger happens close to the start of your monitoring window, you should shift the window earlier — start at 8:00 PM instead of 9:00 PM. Make sure you're capturing the actual first movement, not just the first movement you happened to record.

The same logic applies to the end of the window. If the last trigger is at 5:55 AM and your window ends at 6:00 AM, extend it. You want to see the rodent's final movement before it settles, not have it cut off by your recording window.

Finding the Sweet Spot

Adjust the window over a few nights. Once you see a clear gap between the window opening and the first trigger — say, the window starts at 8:00 PM but the first movement isn't until 10:30 PM — you know you're capturing everything. That 10:30 timestamp is the real departure time.

Why the Focusing Cones Matter

This brings up a practical problem: if you set the monitoring window to start at 7:00 PM to catch early activity, you might also catch yourself walking through the basement to do a load of laundry. Or the kids running through the kitchen. Or the dog.

That's exactly why every RodentRadar kit includes focusing cones for each sensor.

Without a cone, a sensor has a wide detection field — it'll pick up motion anywhere in its vicinity. That's great for broad coverage, but it means human activity in the same room will trigger it. The cone narrows the sensor's field of view, pointing it at a specific area: along a baseboard, behind an appliance, at a gap near a pipe.

Cones + Monitoring Window = Clean Data

The combination of focused sensors and a tuned monitoring window is what removes human motion from the equation. The cone makes sure the sensor is only watching the areas rodents use. The monitoring window makes sure you're only reviewing hours when rodents are active. Together, they give you data you can trust.

Narrowing Down the Source: The Move-and-Split Method

Once you've identified the first movement of the night — the sensor that triggers first, closest to the source — the next step is straightforward. You move sensors toward it and split the difference.

1

Identify the first-trigger sensor

After a night or two, you'll see which sensor consistently fires first. That's your starting point — the rodent is coming from that direction.

2

Move two sensors closer to the source

Take two sensors and reposition them past the first-trigger sensor — one slightly to the left, one to the right. You're splitting the search area in half. Update their positions on your floorplan so playback stays accurate.

3

Wait another night

Review the next morning's playback. Which of the two new sensors triggered first? That tells you which direction to keep moving. The other sensor can be repositioned or used elsewhere.

4

Repeat until you've found it

Keep splitting and moving. Each night narrows the search. Within a few days, you'll be staring at the gap, crack, or opening they're using. The sensors led you right to it.

Don't Forget to Update the Floorplan

Every time you move a sensor, tap its new position on your floorplan in the dashboard. This keeps your playback visually accurate — you'll see the trail of first-triggers literally walking toward the source across your floor plan over several nights.

Example: Tracking a Basement Entry Point

Real-World Example

Night 1 — Initial Placement

Eight sensors spread across the basement — near the stairs, along the far wall, by the furnace, near the water heater, along the foundation walls.

10:12 PM Sensor 7 (far corner, near foundation) — first trigger
10:14 PM Sensor 5 (along wall toward stairs)
10:31 PM Sensor 3 (near furnace)
... Activity continues through the night
4:48 AM Sensor 7 (far corner, near foundation) — last trigger

Takeaway: First and last movement both point to Sensor 7's corner. The source is in that direction.

Night 2 — Move and Split

Two sensors repositioned past Sensor 7's location — one toward the left side of the corner, one toward the right, closer to where a pipe enters through the foundation.

10:08 PM Sensor 2 (right side, near pipe entry) — first trigger
10:09 PM Sensor 8 (left side of corner) — triggers second

Takeaway: The right side, near the pipe. That's the direction. One more night to confirm, then inspect for the gap.

Night 3 — Confirmed

Sensor moved directly adjacent to the pipe entry through the foundation wall.

10:15 PM Sensor 2 — triggers immediately. First event of the night. Daylight inspection reveals a ¾-inch gap around the pipe sleeve where it passes through the concrete. Entry point found.

Closing It Off for Good

Once you've identified the entry point, sealing it is usually the simplest part. Steel wool packed into the gap, covered with caulk or expanding foam. For larger openings, hardware cloth or metal flashing. The important thing is that you're sealing the right spot — not guessing at five different possibilities and hoping one of them was it.

After sealing, leave the sensors in place for a few more nights. If the entry point was the only one, you'll see activity drop to zero. If there's a secondary entry point, the sensors will catch the rodent using an alternate route — and you repeat the process.

That's the Whole Method

Watch for the first and last trigger. Move sensors toward the source. Split the difference. Repeat until you're standing in front of the gap. Seal it. Verify with a few more quiet nights.

Traps catch mice. This process stops them from getting in.

Find the Entry Point

8 sensors + focusing cones. Narrow down the source in days, not weeks.

Get Started — $149

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