You're not stupid! This is a tricky problem, and RF environments can be surprisingly complex. Here's a breakdown of possible causes and why your theory about daytime RF saturation is likely correct, along with some other things to consider

Understanding the Problem
The Symptom

WiFi works great at night over a long distance, but becomes unreliable during the day.

The Context

You know the cables work (so the cameras are generally functional), and you've ruled out ionospheric effects (which are relevant to HF/Shortwave radio, not 2.4 GHz WiFi).

Why Daytime RF Saturation is a Good Suspect



Increased Interference

During the day, many more devices are active, potentially flooding the 2.4 GHz band:

More WiFi Networks

Neighbors use their internet more during the day.

Bluetooth Devices

People are wearing headphones, using wireless mice/keyboards, etc.

Microwave Ovens

Though short bursts, they can cause significant interference.

Cordless Phones

Older DECT 6.0 phones often operate close to 2.4 GHz.

IoT Devices

Smart home gadgets like sensors, lights, and appliances become more active.

Noise Floor Increase

All this activity raises the overall "noise floor" of the 2.4 GHz band. Think of it like trying to hear a whisper in a crowded room versus a quiet one. The same signal strength has a lower Signal-to-Noise Ratio (SNR) during the day.

Why 300+ feet is a problem even at night



2.4 GHz is susceptible to obstacles

The wavelength of 2.4 GHz is relatively short, making it prone to being blocked or weakened by walls, trees, and even moisture in the air.

Power Limitations

WiFi devices, especially those designed for low power consumption in security cameras, have limited transmit power. Over long distances, even small signal losses become significant.

Environmental Changes

Slight changes in foliage (leaves getting heavier with dew) or atmospheric conditions can affect signal propagation.

Additional Factors to Investigate (Beyond General Interference)



Specific Interferers



Look for specific sources of interference near the cameras. Is there a new device that started operating around the time the problem began? A cheap Bluetooth speaker can wreak havoc. Run a WiFi analyzer app on your phone or laptop. These apps show you all the WiFi networks in range, their signal strengths, and the channels they're using. This can help identify potential sources of interference. Look for signals that are especially strong or have a wide bandwidth (which could indicate a non-WiFi interferer). Channel Congestion



2.4 GHz has limited channels. If many networks are using the same or overlapping channels, performance suffers. Your router should automatically choose the least congested channel, but it's worth checking. Consider 5 GHz (if your cameras and router support it). 5 GHz has more channels and is less prone to interference, but it has a shorter range and is more easily blocked by obstacles. Camera Placement and Orientation



Ensure the camera antennas are properly oriented. Experiment with different angles to see if it improves signal strength. Line of Sight

Even partial line of sight can significantly improve performance. Are there any new obstructions that might be blocking the signal?

Router Configuration



Update your router's firmware. Updates often include performance improvements and bug fixes. QoS (Quality of Service)

If your router has QoS settings, make sure they aren't prioritizing other traffic over the security cameras.

Check for Router Interference

Some Routers generate RFI/EMI and can desensitize the receive performance of nearby devices.

Camera Hardware



Antenna Issues

Rare, but sometimes the internal antenna connection in the camera can be loose or damaged.

Power Supply

Ensure the cameras have adequate power, especially if using power over ethernet (PoE). Voltage drops can affect WiFi performance.

Automatic Frequency Selection

Some devices will move channels on their own to try and find the best available signal. This can make finding a channel that works and locking into it for better signal difficult.

What to Do to Improve the Situation

1.

WiFi Analyzer

Use a WiFi analyzer app to survey the 2.4 GHz band and identify congested channels.
2.

Router Channel Optimization

Manually select a less congested channel in your router settings.3.

Move to 5 GHz (if possible)

If your cameras and router support 5 GHz, try switching. Be aware of the shorter range.4.

Reduce Interference

Turn off or move potential interferers (Bluetooth devices, etc.) closer to the cameras.5.

Directional Antennas

If possible, use directional antennas on either the camera or the router to focus the signal in a specific direction. This can significantly increase range and reduce interference. Be careful, as increasing the gain of any antenna may violate local laws.6.

WiFi Repeaters/Extenders

Place a WiFi repeater halfway between the router and the cameras to boost the signal. Use Ethernet and a second wireless access point for a wired backhaul for best results.7.

Re-evaluate Camera Placement

Move the cameras closer to the router or to a location with better line of sight.8.

Consider a Wired Connection

If possible, run Ethernet cables to the cameras. It's the most reliable solution.9.

Camera Firmware

Be sure your camera firmware is up to date.

Why Your Initial Thinking Was Good:

You're right to suspect that the increased daytime RF activity is a key factor. WiFi, especially at 2.4 GHz, is a shared medium, and more users mean more contention and interference. The fact that it works at night is a strong indicator that the problem is related to the changing RF environment.Don't feel stupid! RF troubleshooting can be complex, and there are many variables to consider. By systematically investigating these factors, you should be able to find the cause and improve the performance of your security camera system. Flag for review