Wi-Fi Extender question
 

I am looking to improve the signal to my upstairs computer (router/modem is downstairs). Bought a Netgear Wi-Fi extender.

The signal strength went up and the speedtest speed went down. Huh?
What am I missing?

Not an engineer. Seems to make sense. A boosted signal is just that. A boost. There has to be frictional loss in the boost process.

Is your main router dual band?

Signal strength does not always equate 1:1 with performance.

There are two frequencies, 2.5 and 5.

2.5 is for distance and slower

5 for speed but has a shorter range.

Also, wifi extenders do not give you full throughput of the primary router.

Think of the signals like circles.

Closest to the device is 100% and at the edge of coverage is 0%.

If the devices circles overlap in the middle the extender is only repeating 50% of the signal.

Then there is backhual and a host of other things like WIFI penetrates OK in a horizontal but sucks at vertical.

WIFI is meant for convenience, not performance.

It is perfectly normal behaviour.
Extender is a "band aid" that is actually a repeater. It will receive your data, buffer it and then re-send it to the router. It will not "boost" signal from router, it will pretend to be router and then resend the data. By the nature of 802.11 protocol, when one device is sending everyone else must keep quiet.

So in reality repeater will cut bandwidth in half (more than half in practice) and introduce extra latency.

Extenders are generally frowned upon in industry and never used in business. Proper way to cover larger space with WiFi is by using wired Access Points (also called AP's). Prefferably, AP's should be channel-planned and using different channels in order not to interfere with each other. More modern AP's will also use roaming protocol 802.11r which will allow devices to seamlessly roam from one AP to another without dropouts. Basically, see extender as a "cool collar". It can save you in a pinch (make connection possible) but it is a inferior solution in any other way. If you do not want to install proper wired AP solution you can consider mesh system. It is inferior to wired AP but it will at least use different channel for back-haul, providing somewhat better throughput. It is also easier to install for a layman.

Likely a stupid question...but are you sure your upstairs computer is connected to the repeater network?
I use one outdoors on my deck that gives me a full five bars of signal. Every once in a while...prob because I carry my tablet from inside the house while on...the tablet will have a very weak signal. Looking at my settings, I find it's not on the extender network...I just switch it over and good to go.

What you want is a mesh network so each repeater is a receiver and a transmitter.....yes, adding an access point connected via hard-wire is better, but often more difficult to install.

I’ve had great luck at a few friends’ houses with an amazon product called Eero, works, easy to setup, and capable of handling high speed throughout a large or small house

This is what we went to during quarantine when everyone ended up at home connected at the same time.

It’s worked well for us.

I hated the range extender I bought. Every time I went upstairs I had to switch Wifi networks.

Eventually I bought a mesh network system (Google mesh in my case) and now I have full coverage everywhere and the devices that use Wifi see the entire thing as one big access point.

Most of these radios transmit and broadcast on the same frequency. Because of this, it can either broadcast or receive, not both at the same time. Your 'repeater' is likely having to receive information from the computer, then send it to the network below. It effectively cuts your bandwidth in half, but it increases your distance.

Get a mesh system. eero, Google, etc. Simple, works well, fast, easy to add more stations.

I did the multiple networks and extender thing for years. It was a big PITA.

+1. Extenders halve your speed... Mesh all the way ! I get 800+ up and down on the mesh (itself on fiber)

This is the one I use. Works perfectly. Why spend $200 or more when $22 does the same?
https://www.amazon.com/gp/product/B07QWQD37J/ref=ppx_yo_dt_b_asin_title_o02_s00?ie=UTF8&psc=1
I'm just using mine on the outdoor deck...I'm not gaming with it.

Great info - thanks. A little more detail.

ATT router/modem is 2.4/5 ghz. The 5ghz reaches upstairs but sometime I have the signal drop off. I thought an extender would bring in a stronger signal - it did but at the cost of speed. I was trying a Netgear Wi-Fi Mesh Extender Dual band up to 1200 Mbps. No joy. Going back in the morning. Netgear has another Mesh Extender with even higher speeds and distance but I'm thinking it will still yield a drop in speed since my 5ghz is reaching where I need to go.

How do I know it was connecting? Simple plug in, unplug, compare signals and speed. Plugged in I see the stronger signal but the speed test slows down.

I been told that the modem/router setup is a weak link in wi-fi (can have momentary dropoffs) and it is better to use individual pieces. I looked into replacing the modem/router supplied by ATT but was advised that their Fiber system requires a router and modem they supply (it has to be registered with their fiber system or it won't recognize my modem) and I can't upgrade with non-ATT products. Does anyone know if this is set in stone or is there a workaround?

I don't know how old your router is, but often times new firmware is developed after the product has been released. If you know how to get into the administrative function of your router, you may be able to upgrade the firmware. Newer firmware may improve your router's ability to stay connected, may increase the systems power output, and may decrease the signal to noise ratio.

If you can add a larger antenna to your system, that would likely take care of your problem. Don't worry about amplifiers, antennae are the way to go. You can think of an amplifier as yelling, that works to get the message one way, but if the other side is still whispering, yelling isn't going to help. An antenna increases not only your ability to yell, but it increases the size of your ears too.

You went through these steps...right?

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