Ais 3G Reception Cut By Strange Incoming Signal - Anybody Know What This Is?

[jko]

I have an AIS 3G aircard which I use in a countryside location where there is a strong (90-97%) HSDPA signal. This works fairly well, but quite often I hear a buzzing noise coming through my speakers which sounds like that of an incoming call from another mobile. This immediately cuts my HSDPA to EDGE, and very often breaks the AIS connection completely.

I'm right in the boondocks here - no military installations power lines or other electrical inteference. Also I can go for weeks without any problem - until it suddenly starts again.

No special times of day either - nights same as day. As I write this, it's happening every few minutes, and I've been cut off twice already whilst composing this. I let an AIS (1175 service centre) person listen to the speaker noise, but they were clueless. It's a nuisance and makes internet banking impossible.

Does anybody know what this is? Better still how to solve it?

Grateful for advice.

[barryw52]

Possible a Radar installation or high powered Radio transmitter. Are you near the sea (a ships radar) or from over the boarder other military activity in Laos, Cambodia Burma? Over the horizon radar can have effects a very longway from the source. Another thought is a Radio frequency forming of plastic in a factory manufacturing some product. It could even be a fault electrical appliance in your own house. A motor or microwave oven, fluroesent light etc or even just the switched mode power supply in your PC playing up. Lots and lots of possibilities!! have you tried moving around the house when it happens does it decrease if you move?

[lomatopo]

Does it sound like this:

http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&ved=0CC8QFjAA&url=http%3A%2F%2Faudiojungle.net%2Fitem%2Fcell-phone-incoming-interference%2F166226&ei=E9ukUOjrKtChiAerrICICg&usg=AFQjCNG9HJ1SInAnZyNQtoE_9z7YKyBiQA

If so, this is pretty common, your speaker wires are effectively acting like an AM antenna - you still hear this a lot during big presentations. But not sure why it messes up your data connection - maybe shield the speaker wires, and try to isolate the aircard. Can you use an external antenna? In many cases vocie calls have priority, so if it is a nearby incoming GSM call this might affect your channel but it seems weird. AIS has a real hodge-podge of equipment; they used to shake down suppliers for free evaluation gear, and built their network with a lot of free stuff.

Is this a new occurrence? Any background info? How long have you had the plan? Which SIM/Plan? Aircard make/model? Any other AIS/One-2-Call phones in the house? Nearby?

[talk2sam]

I am having same problem with my Truemove 3G, been using it for 6 months, but it just started this nov. I stay behind a military fort.

[RKASA]

I recall something like this back when I was using AIS GPRS. I would get over the speakers a beep beep beep but more an electronic sounding Buzz and then disconnected. I live near nothing and it came from over the modem. I am guessing it was something to do with spamming sms messages wanting to connect to the number. Now with dtac incoming sms messages 99% of which I don't want - will often hang up my connection after they are received - I hate that. I have it down to just a few per month and most come form dtac telling me I am low on time before refill.

[jko]

Does it sound like this:

http://www.google.co...QtoE_9z7YKyBiQA

If so, this is pretty common, your speaker wires are effectively acting like an AM antenna - you still hear this a lot during big presentations. But not sure why it messes up your data connection - maybe shield the speaker wires, and try to isolate the aircard. Can you use an external antenna? In many cases vocie calls have priority, so if it is a nearby incoming GSM call this might affect your channel but it seems weird. AIS has a real hodge-podge of equipment; they used to shake down suppliers for free evaluation gear, and built their network with a lot of free stuff.

Is this a new occurrence? Any background info? How long have you had the plan? Which SIM/Plan? Aircard make/model? Any other AIS/One-2-Call phones in the house? Nearby?

First - my thanks to all for the replies.

Thanks particularly to lomatopo, for the helpful & detailed advice. The sound you considerately linked to is the same, but there are longer 'buzzes' mixed with the short clipped ones, whatever that indicates. I've had this AIS aircrd for two years, and it has worked well apart from these interludes, which began and continued on and off about six months ago. I'm beautifully isolated on elevated ground in a forested area with no houses, factories or other buildings around, and not near any miitary installation.

Re speakers - you could well be right. I've now plugged them in to a different power socket and - so far so good - it hasn't happened since. That might be a coincidence, but I'll report back on this.

Renewed thanks meanwhile - much appreciated!

[bobl]

I think many people will have heard this noise, if they've ever left their phone too close to the speakers, hifi, tv... Basically your radio (aircard) is too close to your speakers and/or the wires connecting them.

What you're hearing is the 'handshake' between your device and the telco - the noise will vary depending whether it's just a handshake ("hello?" "yes I'm still here"), or an incoming text or phone call. In fact often it's like an early warning system and you can tell you're about to receive a text or a phone call.

The range at which speakers are affected is usually quite short even with a cheap pair of usb or mains powered laptop/pc speakers. Simply moving your aircard a couple of feet would fix it. If it's plugged directly into USB, simply get an extension cable or something slightly more exotic like this:

Edit: Forgot a part

(It's not uncommon for a high speed connection to drop off for whatever reason. The disconnect is usually transient and the thing locks onto the hs carrier again quite quickly. In your case it's the negotiation for a reconnection you're hearing. Coincidentally, my speakers in the laptop are doing exactly this right now, because I have the phone sitting on top of it where I connected it to transfer that photo)

Edited November 17, 2012 by bobl

[jko]

I'd like to report that since plugging my speakers into a different electrical socket, the problem has not recurred.

Wonderful.

Simple solution - I should have thought out of the box maybe - but my thanks to all who responded!