Shield / dampen 2.4 GHz WLAN - how?

My (newly moved) neighborhood has a strong 2.4 GHz WLAN installed - probably a new UPC box.

Unfortunately, the neighborhood’s WiFi transmitter is now almost directly behind the wall on which I want to operate my Bluetooth headset - Bluetooth is also on 2.4 GHz.

I would now like to take measures to attenuate the unwanted 2.4 GHz WLAN signal “at my place” so that the interference for Bluetooth is significantly reduced:

a) Install any EMC device (2×2 meters?) on my wall as a damper - e.g. aluminum foil, vapor barrier with aluminum coating, [Naturally: Swiss Shield (swiss-shield.ch)](https://www.swiss-shield .ch/index.php?id=19)

b) Motivate neighbors to install a “damping plate” behind their router

What I don’t know is how effective such a damping device can be. All I really care about is that the 2.4 GHz WiFi cloud no longer radiates omnidirectionally into my Bluetooth.

Is there any practical experience here? Other forums with testimonials?

To differentiate: Of course I’m still looking for other options, e.g. “Bribe: turn off 2.4 GHz” or “Bribe: reduce transmission power” or “Change headset Bluetooth -> DECT”. Spatial relocation is difficult.

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WalterB wrote:

Why do you come to this conclusion that you have a problem?

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I don’t make any assumptions 😉

My problem is that the “foreign” 2.4 GHz transmitter is now installed approx. 60cm from my Bluetooth base. That’s roughly as if I were placing my Bluetooth base directly on my Swisscom Internetbox 2.

The result is that people are now complaining about chopped Bluetooth audio in conference calls, that I’m getting spontaneous Bluetooth disconnects and reconnects, and that my Bluetooth range has dropped drastically.

In other words: the new foreign 2.4 GHz WLAN is a problem for me and my Bluetooth headset at the location where I use it. After reading “Spatial relocation is difficult.” As already mentioned, I’m looking for alternatives to reduce the influence of the new 2.4 GHz WLAN on my Bluetooth.

Based on very rough RSSI measurements, I’m sure I know a place in my apartment where the new 2.4 GHz transmitter wouldn’t be a problem. But: *I* don’t want to go there.

Regarding your neighborhood, it probably doesn’t matter whether the Internet comes from Salt, Wingo, UPC, Swisscom or whatever. What is more important is which WiFi transmitters your neighborhood uses and whether you want to use your Bluetooth headset within 60 cm of exactly this 2.4 GHz transmitter (I doubt that).

I also have other 2.4 GHz transmitters _in the area_, but they are not 60cm away but probably at least 10m (2x) and then through ceilings and walls.

For context, a screenshot from an Android phone with “WiFi Analyzer” taken in the location where my Bluetooth audio wants to survive:

* green == the foreign 2.4 GHz WLAN

* blue == I’m not interested

* red == my Swisscom Internetbox 2, about 5m away, behind very thin material

You can see that I’m basically sitting on the foreign 2.4 GHz WLAN transmitter and I just want to turn it down.

This video provides a bit of context for my question: Shielding RF Radiation with Aluminum Screening - YouTube

I fully recognize the neighborhood’s right to operate 2.4 GHz transmitters (here: a WLAN). At the same time I try to use Bluetooth on 2.4 GHz. Due to the current spatial conditions, this is new / just a bit unfortunate. That’s why I’m checking the path “dampen out foreign WLAN”.

Ultimately, this may come down to me bribing the neighborhood to simply turn off the 2.4 GHz transmitter; Effectively, that probably wouldn’t cause any pain to the newly tamed neighborhood and would keep my Bluetooth happy.

But if the neighborhood doesn’t feel comfortable with “turning off 2.4 GHz” (or reducing power - it’s only 40 square meters over there!), then I need other solutions - and dampening the EMC emissions on my side is what I’m potentially completely under *my* control.

PS: Shared spectrum == bad spectrum. That’s why my other infrastructure is basically connected via cable. Only: I want the headset to be wireless (and, yes, I’m looking at DECT as an option)

I even have a router with 3x RP-SMA. So I buy three Yagi antennas for CHF 30 each, clear out my desk and do a full roast. 🤣

Seriously, an attenuation of -44 dB by 30 dB to, say, -70 dB would probably be enough for me to be able to use the Bluetooth headset at my preferred location without any worries. In the midst of all the… radiation websites… I’m just having a hard time finding really reliable, documented solutions to the problem.

I don’t want to buy a 10 square meter rabbit fence from the Bauhaus, only to find out that it’s not a complete solution either in terms of appearance or shielding technology. I’m looking for statements like “Swiss Shield works in a measurable way” (also a fence or whatever can be functionally integrated) and “you really get the 30 dB attenuation on 2.4 GHz under the following conditions”.

For example, if I go to [https://www.a-zgesund.ch/modules/wbsShop/index.php?cat\_id=19&location\_id=71](https://www.a-zgesund.ch/modules/ wbsShop/index.php?cat_id=19&location_id=71), then I’m missing a little substance behind the “buy me and then you’ll be totally fine” (which may or may not be true - I’m looking for resilient substance, not radiation protection blankets with a “comfortable place” patch). Purely theoretically, yes [https://www.a-zgesund.ch/shops/83/137/71/erwachsene-kinder/tuch-grosses-quadrat-aus-swiss-shield-naturell-250-cm-x-250-cm] (https://www.a-zgesund.ch/shops/83/137/71/erwachsene-kinder/tuch-grosses-quadrat-aus-swiss-shield-naturell-250-cm-x-250-cm) Easy to integrate into the interior, also visually, but CHF 350 for the experiment to see whether the thing really attenuates 30 dB at 2.4 GHz, I think… quite a lot.

PS: The website mentioned is simply some Google hit, no recommendation, criticism or anything similar is implied, just an arbitrary reference.

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hed wrote:

Move your BT base by 1m and it’s good.

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No - my BT base is a significant part of the problem - but my BT headset is also only 80 cm away from the foreign 2.4 GHz transmitter. In other words: I’m sitting exactly opposite the neighbor’s WiFi router.

But I’m definitely looking into moving the BT dongle in a different direction - USB extension for

The printer (which can only do 2.4 GHz) also complains about lousy WiFi, but it prints. That’s enough for 20 pages/year.

I rebuilt my USB world a little experimentally - the USB dongle now hangs around the room more freely (still to be optimized visually), is now roughly one meter further away from the original location, completely isolated from hubs and directly on its own a botched extension.

At the same time, the neighborhood has continued to rein in - I suspect the access point has been restarted and is now on channel 11 (where almost the entire neighborhood meets right now…)

As a result, my Bluetooth audio (Plantronics / Poly Voyager 5200 -> Plantronics / Poly BT600) has just gotten a lot better.

The story will probably continue for a while 😉