View Full Version : PC kills cellphone reception

04-01-2018, 12:50 PM
Talking on my mobile phone while sitting at my computer frequently drops the call. Text messaging is delayed as well. I have wired VDSL. My cellphone provider signal is in a marginal reception area. 95% of the time it works OK, providing I'm not within a couple of metres of the computer.
It has been like this for some years only now I want to quit my landline phone handpiece so I need better performance from the Samsung Galaxy.
I thought about putting the PC in another room and running appropriate cables. Also placing the tower inside a metal box, allowing it to breath of course.
Is there some better ideas or workarounds??

04-01-2018, 02:27 PM
Where are you located, and who's your mobile provider? When I was at my ex's beach house back-of-beyond any cell phone reception was marginal, but found that Spark's signal was the strongest.

Terry Porritt
04-01-2018, 02:32 PM
Like as not the switching in the PSU is generating RF and transmitting it into the mains leads, and there may also be GHz frequencies floating around too.

The first place to start is by adding an RF filter where the mains lead is plugged into the PSU:

Stopping RFI is not easy, and "some suck it and see" is usually needed, like winding leads through toroids.

Terry Porritt
04-01-2018, 02:46 PM
Jaycar sell a 6 amp filter which is what would be needed for a PSU https://www.jaycar.co.nz/iec-emi-power-line-filter-6-amp/p/MS4003

04-01-2018, 02:50 PM
Where are you located, and who's your mobile provider? Outskirts of Hamilton. Provider is Skinny which is a division of Spark.

04-01-2018, 03:15 PM
Jaycar sell a 6 amp filter which is what would be needed for a PSU https://www.jaycar.co.nz/iec-emi-power-line-filter-6-amp/p/MS4003Thanks. Worth a try.

It's like my house is in a shadow, reception-wise. I have learnt to leave my phone on the kitchen table where it gets one bar. I sometimes get two bars if I walk out to the deck. Three bars on a good day if I simply stroll out to the road. Walk either way along the road and reception improves..
If I'm sitting at the PC with phone in pocket, the moment I walk away is when a text comes in. Reality is it's been trying to connect for the last 20mins.

OK, so I've decided to swap VDSL providers and go with Skinny. I'll save $37 a month not having the landline phone. Not many calls coming in the phone anymore, only Microsoft calling about problem with your Windows PC sir! Haha, yeah, you know what I mean!

I have to try things. It would be great to be able to use the cellphone and look at the PC screen at the same time. Funnily the suggestion elsewhere was a lead kryptonite barrier.

Suggestions appreciated. Thanks.

04-01-2018, 03:41 PM
Iíd be inclined to disconnect the PC from the power point and see if your reception improves.

Then plug the PC back in but donít turn PC on and check again.

Finally, fire your PC up and check again.

You will have to leave your phone in the position you intend to leave it for all tests.

All Iím trying to establish is if indeed your PC is in fact effecting your reception.

It may well be that the PC has nothing to do with the problem, itís just your location in the house and relocating your office might be necessary.

Thatís where Iíd start anyway. :)

04-01-2018, 09:35 PM
You could try using a power cord with a ferrite bead in it, or adding one to your power cord. They used to be fairly common on power cords but most people ignore them so you might have one and not know it - the cylindrical bulge at one end of the cable. I think this is the same as what Terry was meaning with a toroid but the inline cylindrical version is a little easier although probably less effective. Add on ones look like this https://www.jaycar.co.nz/u25-ferrite-voltage-spike-protectors-noise-suppressors-each/p/LF1290

Interference goes both ways, when I was on vodafone I could hear a txt coming on the PC before the phone received it. I've heard that same noise on tv shows so I know it's not just me.

04-01-2018, 11:44 PM
I tried the suggestion by B.M. It appears to be the PC though we're only talking about a one bar signal that fluctuates at the best of times. Today is a particularly poor signal I suppose due to weather. Anyway I'll re-conduct the experiment and look for result consistency.

The ferrite choke idea is an easy one. Thanks Dugimodo. I'd have some of those amongst my pile of old PC stuff. Perhaps there might even be a cord with one of those already fitted. Otherwise are they fussy how they're fitted? else I'd have find a 3pin plug to re terminate.

Ok, the plan so far.
1/. fit ferrite bead/s.
2/. Move the tower further away. Perhaps adding 1m or more distance.
3/. Erect a tin barrier.

05-01-2018, 03:47 AM
Try setting the phone into signal strength mode, bars are a pretty meaningless way of measuring signals.

Your room will be a deadspot if your only getting 1 bar. Any large metalic objects nearby, or led screen etc will be enough to knock it out

05-01-2018, 08:19 AM
Interference goes both ways, when I was on vodafone I could hear a txt coming on the PC before the phone received it. I've heard that same noise on tv shows so I know it's not just me.

I haven't had this happen for years but it used to happen a lot.

05-01-2018, 01:42 PM
I think the ferrite choke should be near the equipment end, but I don't know the specifics of how they work.
If you try a metal barrier it will work best if you put an earth on it.

05-01-2018, 03:03 PM
I found the Signal Strength Meter in my Galaxy J5.

Outside on road frontage 93 dBm , 10 asu (best reading within 2 mins period)
On deck at back of house 101 dBm , 6 asu (best reading within 1 min period)
Room where PC is (range) 101 dBm , 6 asu - 113 dBm , 0 asu (range of readings over 2 hours)

It didn't seem to make much difference whether the PC was powered up or not. At this moment I think poor signal strength is the main problem. Will do the things mentioned earlier as I find the parts and time. Hopefully with good weather and some small improvement/s it might just swing the odds my way.

Ideal would be "wifi calling", studying it atm along with other apps. Looks like I gotta upgrade the J5 for a start..

05-01-2018, 08:17 PM
Have you tried WhatsApp or one of its its equivalents? You would then be on data instead of cellular - presuming of course the person you call has the same App, and not subject to the same reception problems

05-01-2018, 10:22 PM
Have been studying WhatsApp. Probably go with it. Review once wifi calling becomes available.

06-01-2018, 12:37 PM
But do you have WiFi at home with your VDSL? If so just load WhatsApp from the play store and use it. You will be surprised how many of you contacts have it

06-01-2018, 05:34 PM
What's app Viber and plenty of others allow that, few of us use WhatsApp but most of us use Viber inour circle so find out what your friends and family use first

06-01-2018, 06:51 PM
Turned out about 15 contacts use WhatsApp. Before I installed, I cleaned out lots of old contacts. It seems that at some stage my email handler decided to add people to my contact list on an "if in doubt basis".

10-01-2018, 09:55 PM
2degrees brings wifi calling to NZ (http://www.stuff.co.nz/business/industries/99252388/2degrees-brings-wificalling-option-to-nz)
2degrees will first offer wifi calling as an option to about 30,000 customers who have Samsung S8 and S8+ handsets.
It's a start...!

10-01-2018, 10:08 PM
BTW does your computer have a cordless mouse or keyboard?

10-01-2018, 10:38 PM
BTW does your computer have a cordless mouse or keyboard?
No, neither.