WiFi Issues & Answers

WiFi 101:

Many years ago the FCC allocated frequencies in the 2.4 Gigahertz (GHz.) range for WiFi.

They gave us eleven channels that are spaced 5 Megahertz (MHz.) apart for a total of 55 MHz. of the radio spectrum.

The people who set the standard for WiFi (the IEEE) in 1999 realised that each 5 MHz. channel by itself could not carry much data.

(The wider the channel, the more data capacity it has.) The answer was to make the signals 20 MHz. wide instead of 5 MHz.

The FCC didn't give them more frequencies, the IEEE had to squeeze the 20 MHz. wide channels into the existing space.

Instead of having eleven channels 5 MHz. wide, we now have only three channels 20 MHz. wide that don't overlap.

Channels 1, 6, and 11 are used in the US almost exclusively for this reason.

A common belief is that if, for instance, channel 1 is in use, you can simply move to channel 2 or 3.

Unfortunately, It doesn't work that way. Channels 2 and 3 are partially covered up by the 20 MHz. wide channel 1 signal.

Two devices that are on, or nearly on the same channel and that are in close proximity will not coexist without problems.

It becomes evident that any unnecessary device spitting out WiFi or radio waves in the WiFi band should be eliminated.

There are also 5 GHz. WiFI routers on the market. 5 GHz. doesn't penetrate walls and floors nearly as well as the 2.4 GHz.

Sometimes it will take three 5 GHz. routers to cover the same size home that one 2.4 GHz. WiFi router will easily cover.

Also, while 5 GHz. devices are becoming more common, some devices in use today will only operate on the 2.4 GHz. frequencies.

Consider any of the following devices to be a potential source of WiFi interference.

Cordless Phones:

There are basically 3 types of cordless phones grouped here by the radio frequencies that they utilize.

Very old cordless phones used the 49 MHz band.

Remember those old cordless phones with the collapsible antennas?

These are very rare today and are generally not any threat to your WiFi, but they should be retired.

Some of the newest cordless phones use the same frequencies as your WiFi (2.4 and 5 GHz.).

Most will utilize all eleven of the 2.4 GHz. channels at once!

Even the newer "Spread Spectrum" models are problematic.

These WILL cause problems and should be replaced.

The best cordless phones use a newer technology called DECT 6.0 and operate in the 1.9 GHz. range.

These will not interfere with WiFi, plus they work much better than any of the older types of cordless phones.

When shopping for cordless phones, only consider DECT 6.0 models. You won't be disappointed!

Baby Monitors, Wireless Cameras, Wireless Speakers and Door Locks

Lots of these devices use the 2.4 and 5 GHz frequency band.

Just like cordless phones, some use all eleven of the 2.4 GHz. channels at once and will cause problems!

Only consider buying ones that do not use these frequencies.

If you can't verify what frequencies they use, avoid them.

Microwave Ovens

All Microwave ovens operate in the 2.4 GHz. range of frequencies. Yes, the same as your WiFi!

One good thing is interference can only occur while the oven is heating and should disappear as soon as the oven stops.

Position computers, routers and other devices as far away from microwave ovens as possible.

Motor Vehicles

Newer GM, Ford, Toyota, and most others have powerful WiFi hotspots built in and they broadcast even when the vehicle is not running.

This is a HUGE problem for campgrounds and motels where they could have hundreds of them spewing out WiFi 24/7.

If you have (or your neighbor has) one in your garage or driveway, it could be a source of interference.

Check your owner's manual, ask your dealer or search the Internet for instructions on how to disable the WiFi in your specific vehicle.

WiFi HotSpots and Range Extenders

All smartphones and tablets can be set up to be a WiFi hotspot.

That means the device is used as a WiFi portal for others to access the Internet using your data plan.

Hotspots should be disabled on every device on the premises and only enabled when needed.

If you have our Internet service, you don't need a hotspot running!

Range Extenders are hotspots that repeat the WiFi signal. They are horribly slow and are rarely set up properly.

Only the most expensive ones are capable of working without causing more problems than they fix.

If a range extender is necessary, it should be professionally installed.

Bluetooth Devices

Bluetooth shares the 2.4 GHz. band too!

Older devices were capable of some serious WiFi interference.

Newer Bluetooth devices coexist much better than the older ones did.

Some older cars have Bluetooth that can cause problems.

If your problem goes away when you turn off your earpiece or your smartphone's Bluetooth capabilities, you need an upgrade.


Neighbors' cordless phones, WiFi, cameras, cars, etc. can cause you problems.

One saving grace is that the signals don't travel great distances without quickly losing strength.

People living in subdivisions or apartment complexes can expect the worst interference from the neighbors' devices.

HP Printers (and others)

I saved the worst offender for last.

Printers are the most common source of WiFi interference problems that I see in homes and businesses today.

Most HP printers offer wireless services that WILL interfere with your WiFi network.

Printers are usually located inside the house near the area where you need YOUR WiFi to work!

Several universities have banned the use of HP printers on campus unless the WiFi is completely disabled.

Other brands may have started doing the same thing. HP is by far the most prolific.

If you unplug your printer from the power source and your WiFi improves, read on...

Here's how to turn this service off on a few HP printers to keep wireless functioning properly in your area.

If your specific printer is not listed, or the generic instructions do not work, search the Internet for model specific instructions.

For most HP models

Use the menu to navigate to Setup, then Network, then Wireless Radio (on some models, this is towards the bottom of the scrollable menu). Turn the Wireless Radio OFF.

For HP Photosmart d110

Some models may allow you to press the blue "wireless" button on the bottom front of the printer to turn the light out and service off. You may need to hold the button for 5 seconds to turn the light out.

If this is not successful, use the menu to navigate to Settings > Wireless > Wireless settings > Disable Wireless > OK

For HP Laserjet p1102w

Press and hold the "wireless" image button on the left-hand button panel for 5 seconds to turn the light out and service off.

For HP Photosmart c4780

From the front panel, choose "Scan". Scroll up or down to find Networking. Select this, then turn off Wireless.

If wireless indicator persists

Shut the printer down. Then, hold the "wireless" and "cancel" buttons together while powering the printer back on. Wait for all the lights to flash together and then let the buttons go.

In Conclusion

The best speed and reliability will always be through a wired connection going straight into the router.

This is not always practical as lots of devices don't have ethernet ports to plug into!

Plus, we all love the portability that WiFi gives us.

Plugging straight into the router with a cable is a great way to see if your problem is WiFi related.

If a cabled connection works much better than the WiFi does, consider possible WiFi interference.