A conversation occurred today in the bar after a friend returned from
Waitrose in Weybridge.
Apparently (and some say it's becoming common!?) when you enter a
Supermarket the signal strength of your mobile drops off - or is blocked -
perhaps to avoid you making/receiving mobile telephone calls in a
Supermarket!
Before I list a few comments, may I first say that I am/was a techy in the
RF and Satellite frequency fields and that is why this bloke addressed me
first:-
My comments then to him and others and now to you guys were and are thus:-
1. What Commercial reason would they have to do that? My wife calls me to
confirm the shopping list (whoever is doing the shopping) ie: no fresh
Salmon - how about Trout - or don't forget Nappies etc....... or I'm nearly
finished, pick Baby and I up in 20 minutes, or - where the feck are you -
and they/she or I always get through (so far in Tesco's, Addlestone).
2. If it was a Cinema or Library then fine - get a broadband blocker to stop
assholes who answer calls in silent areas.
3. If above (2) was the case then what about Doctors on Call whilst Shopping
or adjacent dwellings being denied public mobile communications?
4. Forget the Hospital/Petrol Station Theory of interfering with equipment:-
as broadband blockers would too hinder such equipment (not to mention
Hospitals renting their roofspace to T-Mobile/Orange/O2/ etc (see Ashford
Mddx).
5. Maybe the "trollies that can't be taken further than 100m from the
Supermarket" - well that's my best offer but my mobile still works in Tescos
Addlestone which had the highest number of trash shoppers pushing the
trollies to their homes across the road until that branch installed the "you
can't move it far - locked trolley wheel" a few years ago - whereas Waitrose
in Weybridge has never really had a "nicked trolley" problem.
> Hi folks,
>
> A conversation occurred today in the bar after a friend returned from
> Waitrose in Weybridge.
>
> Apparently (and some say it's becoming common!?) when you enter a
> Supermarket the signal strength of your mobile drops off - or is blocked -
> perhaps to avoid you making/receiving mobile telephone calls in a
> Supermarket!
Complete crap.
My job takes me in and out of around 20 supermarkets a week. In about
25-30% of them, I can use my phone. In some of the rest, I can use it in
some areas of the store (mainly back areas), in the remainder I can't
get a signal at all.
I haven't looked at the building design and construction materials and
compared it with the phone signal yet, but I have a feeling that's
partly the reason why my phone works in some and not others.
If you look at the roof-space of any supermarket without a suspended
ceiling, you'll see why a phone probably wouldn't work in there.
--
SteveH 'You're not a real petrolhead unless you've owned an Alfa Romeo' www.italiancar.co.uk - Honda VFR800 - Hongdou GY200 - Alfa 75 TSpark
Alfa 156 TSpark - B6 Passat 2.0TDI SE - COSOC KOTL
BOTAFOT #87 - BOTAFOF #18 - MRO # - UKRMSBC #7 - Apostle #2 - YTC #
On 11 Feb, 21:50, "Mark Jones Laptop2" <m...@btinternet.com> wrote:
> Hi folks,
>
> A conversation occurred today in the bar after a friend returned from
> Waitrose in Weybridge.
>
> Apparently (and some say it's becoming common!?) when you enter a
> Supermarket the signal strength of your mobile drops off - or is blocked -
> perhaps to avoid you making/receiving mobile telephone calls in a
> Supermarket!
>
> Before I list a few comments, may I first say that I am/was a techy in the
> RF and Satellite frequency fields and that is why this bloke addressed me
> first:-
>
> My comments then to him and others and now to you guys were and are thus:-
>
> 1. What Commercial reason would they have to do that? My wife calls me to
> confirm the shopping list (whoever is doing the shopping) ie: no fresh
> Salmon - how about Trout - or don't forget Nappies etc....... or I'm nearly
> finished, pick Baby and I up in 20 minutes, or - where the feck are you -
> and they/she or I always get through (so far in Tesco's, Addlestone).
none - our tesco sells phones and is happy to show you them working !
> 2. If it was a Cinema or Library then fine - get a broadband blocker to stop
> assholes who answer calls in silent areas.
i take it you mean a mobile phone blocker - not practical for
emergency reasons
> 3. If above (2) was the case then what about Doctors on Call whilst Shopping
> or adjacent dwellings being denied public mobile communications?
> 4. Forget the Hospital/Petrol Station Theory of interfering with equipment:-
> as broadband blockers would too hinder such equipment (not to mention
> Hospitals renting their roofspace to T-Mobile/Orange/O2/ etc (see Ashford
> Mddx).
mobile phones interfere with maybe 5% of hospital equipment at close
range (5m or closer ) and that tends to be older equipment. Risk
factor ban mobiles on hospital sites.
> 5. Maybe the "trollies that can't be taken further than 100m from the
> Supermarket" - well that's my best offer but my mobile still works in Tescos
> Addlestone which had the highest number of trash shoppers pushing the
> trollies to their homes across the road until that branch installed the "you
> can't move it far - locked trolley wheel" a few years ago - whereas Waitrose
> in Weybridge has never really had a "nicked trolley" problem.
>
> Any ideas of is this a new Urban Myth?
>
> Mark
If its anything like my local Tesco then its a giant metal bin upside
down, question answered.
In an earlier contribution to this discussion,
systemtek <duncan@systemtek.co.uk> wrote:
>
> mobile phones interfere with maybe 5% of hospital equipment at close
> range (5m or closer ) and that tends to be older equipment. Risk
> factor ban mobiles on hospital sites.
>
Far more likely that the ban is to force patients to use the grossly
over-priced in house phone system.
--
Cheers,
Roger
______
Email address maintained for newsgroup use only, and not regularly
monitored.. Messages sent to it may not be read for several weeks.
PLEASE REPLY TO NEWSGROUP!
> In an earlier contribution to this discussion,
> systemtek <duncan@systemtek.co.uk> wrote:
>
> >
> > mobile phones interfere with maybe 5% of hospital equipment at close
> > range (5m or closer ) and that tends to be older equipment. Risk
> > factor ban mobiles on hospital sites.
> >
>
>
> Far more likely that the ban is to force patients to use the grossly
> over-priced in house phone system.
Is the right answer....
--
SteveH 'You're not a real petrolhead unless you've owned an Alfa Romeo' www.italiancar.co.uk - Honda VFR800 - Hongdou GY200 - Alfa 75 TSpark
Alfa 156 TSpark - B6 Passat 2.0TDI SE - COSOC KOTL
BOTAFOT #87 - BOTAFOF #18 - MRO # - UKRMSBC #7 - Apostle #2 - YTC #
"Mark Jones Laptop2" <maj66@btinternet.com> wrote in message
news:KYednfID2p40ElLYRVnyhgA@bt.com...
> Hi folks,
>
> A conversation occurred today in the bar after a friend returned from
> Waitrose in Weybridge.
>
There you have it, too much drink. If you want a lesson in RF design,
technology and propagation I can give it. To keep it simple, look at the
building then find out where the nearest phone mast is for the company you
use. 800/900MHz is severely attenuated by brickwork and metal -
1800/1900MHz even more. In my local Tesco I can't use Tmobile but can use
Vodafone, it all depends on where the masts are and what is blocking the
signal. If I go near the door I can use Tmobile.
Simple as that. Phone jammers are illegal and their presence is monitored
by OFCOM who have a remote monitoring and location system in each town now
covering 100KHz to 10GHz. Everything links to their spectrum monitoring
facility in Baldock.
"Roger Mills" <watt.tyler@googlemail.com> wrote in message
news:539jrgF1qk3luU1@mid.individual.net...
> In an earlier contribution to this discussion,
> systemtek <duncan@systemtek.co.uk> wrote:
>
>>
>> mobile phones interfere with maybe 5% of hospital equipment at close
>> range (5m or closer ) and that tends to be older equipment. Risk
>> factor ban mobiles on hospital sites.
>>
>
>
> Far more likely that the ban is to force patients to use the grossly
> over-priced in house phone system.
> --
> Cheers,
> Roger
> ______
I know a number of NHS hospitals that are paid by phone networks for siting
their equipment and aerials on the roof. Medical equipment should be up to
the current standards and if it isn't then the manufacturer must have lied
or sold it illegally as they must meet a minimum requirement. Mobiles do
not interfere with genuine medical equipment, I have tested this a number of
times. It is only equipment with a lack of filtering and shielding and were
the manufacturer used cheap badged imports and cut corners that suffers.
One hospital I looked at had a sign warning people to switch off their
mobiles, but only 50ft above had a mobile aerial and equipment on the roof.
It's a load of crap and the media scare tactics. Large manufacturers don't
want people to know what corners they cut and which particular equipment
lacks RF immunity from anything nearby. That includes legal radio stations
and their own pager systems.
maj66@btinternet.com declared for all the world to hear...
> Hi folks,
>
> A conversation occurred today in the bar after a friend returned from
> Waitrose in Weybridge.
>
> Apparently (and some say it's becoming common!?) when you enter a
> Supermarket the signal strength of your mobile drops off - or is blocked -
> perhaps to avoid you making/receiving mobile telephone calls in a
> Supermarket!
It's not deliberate, but a by-product of the way the building is
constructed (large metal-frame cage - Faraday)
--
Regards
Jon
duncan@systemtek.co.uk declared for all the world to hear...
> > 2. If it was a Cinema or Library then fine - get a broadband blocker to stop
> > assholes who answer calls in silent areas.
> i take it you mean a mobile phone blocker - not practical for
> emergency reasons
dev@audiospecialists.net declared for all the world to hear...
> One hospital I looked at had a sign warning people to switch off their
> mobiles, but only 50ft above had a mobile aerial and equipment on the roof.
I agree with you, however consider that in a hospital with transmission
equipment on the roof none of the power from that equipment will enter
the hospital itself as it radiates outwards parallel to the ground,
maybe with 5-10 degrees downward tilt. It does not radiate straight
down.
--
Regards
Jon
"Schtop!" <matt.bowden1@gmail.com> wrote in message
news:1171272538.619318.11180@j27g2000cwj.googlegro ups.com...
> Isn't the thing about the Supermarkets that they have huge freezers
> and that this blocks the mobile phone signal?
>
> I always notice that my signal drops as I move into frozen food...
>
> Maybe it's the potato waffles? They are notoriously versatile...
If they were *diversatile* maybe they would improve reception?
(Diversatile, diversity, get it? No? I better get my coat).
"Mark Jones Laptop2" <maj66@btinternet.com> wrote in message
news:KYednfID2p40ElLYRVnyhgA@bt.com...
> Hi folks,
>
> A conversation occurred today in the bar after a friend returned from
> Waitrose in Weybridge.
>
> Apparently (and some say it's becoming common!?) when you enter a
> Supermarket the signal strength of your mobile drops off - or is blocked -
> perhaps to avoid you making/receiving mobile telephone calls in a
> Supermarket!
>
>
I think you will find that the reason is to do with the fact that
supermarkets are getting bigger and have metal roofs. Often they have metal
sides too.
Google "Faraday cage" to understand why you get no signal.
Dave {Reply Address In.sig} wrote:
> As for having a mast on top of the hospital, that will be radiating most
> of its power to the sides, not down. As such, it's probably better to
> have it on the roof than on the roof of an adjacent building. Also,
> provided it has been tested and found to be OK, having a good signal
> will tend to result in mobiles in the building reducing their output
> power and so giving less chance of the mobiles interfering with hospital
> kit.
Urrr, you can't have it both ways. If the signal radiates outwards then
mobile phones in the building below will not see the mast at all and so
will need to be pushing out masses more radiation than if it were in the
next building.
Roger Mills wrote:
> In an earlier contribution to this discussion,
> systemtek <duncan@systemtek.co.uk> wrote:
>
>> mobile phones interfere with maybe 5% of hospital equipment at close
>> range (5m or closer ) and that tends to be older equipment. Risk
>> factor ban mobiles on hospital sites.
>
> Far more likely that the ban is to force patients to use the grossly
> over-priced in house phone system.
My GP's surgery has a large sign above Reception stating that all
mobiles must be turned off due to the risk of interfering with medical
equipment... I know for a fact that that's total rubbish, and that it's
nothing more than the "irritation factor" of mobiles which has provoked
the ban.
And when you hear that patients who are actually in the surgery having
their 5-min appointment will quite happily answer their phone and launch
into a chat mid-consultation, you can understand the reasoning!
"Lobster" <davidlobsterpot601@hotmail.com> wrote in message
news:zg4Ah.17451$Da4.9932@newsfe6-gui.ntli.net...
>
> My GP's surgery has a large sign above Reception stating that all mobiles
> must be turned off due to the risk of interfering with medical
> equipment... I know for a fact that that's total rubbish, and that it's
> nothing more than the "irritation factor" of mobiles which has provoked
> the ban.
>
By the same token I've noticed a few "tourist" places lately, starting to
request all mobiles are switched off before going in (even citing "security
reasons" in one pace) - I was in Hampton Court Palace only yesterday where
they had it.
- Not liking photography indoors for the commercial security of protecting
their revenue-streams... they wouldn't sell so many postcards if you could
take cameras inside. I don't agree with this, but at least there's some
logic to it. I'd rather they're just honest though, and say "no cameras or
camera phones"
- The distraction factor of people nattering away. Entirely fair enough.
- The "interference with sensitive equipment" argument really doesn't
apply...
So then, if your phone is in silent mode and has no camera facility there's
every reason to just, er, not get caught...
>
> Any ideas of is this a new Urban Myth?
>
> Mark
>
>
>
It's a new urban myth. However it's a good idea, as half of
the morons on mobile phones in supermarkets end up stood in
the way yapping away like something posessed, and being
generally irritating.
So bring it on supermarkets, introduce these frequency
blockers I think it's a great idea, even though it's currently
illegal I beleive to interfere with radio signals this way.
On Mon, 12 Feb 2007 07:49:58 +0000, "Dave {Reply Address In.sig}"
<"noone$$"@llondel.org> wrote:
>
>As for having a mast on top of the hospital, that will be radiating most
>of its power to the sides, not down.
Thats a shame. Perhaps they could kill two birds with one stone by
resiting the antennae so that maximum radiation is downward,crank up
the power to a couple of Kw then everyone would receive a cracking
phone signal AND the MRSA superbugs and CDIFF may just get irradiated.
Mark Jones Laptop2 <maj66@btinternet.com> wrote:
> 2. If it was a Cinema or Library then fine [...]
No, it's not fine. I take my phone with me to the cinema so that the
babysitter can contact my wife and I in an emergency. It /is/ on vibrate,
though, and I wouldn't answer it in the auditorium itself.
Dev <dev@audiospecialists.net> wrote:
> I know a number of NHS hospitals that are paid by phone networks for
> siting their equipment and aerials on the roof.
....in which case the phones notice and reduce their power output
accordingly. This can then make for /less/ interference, not more!
"Lobster" <davidlobsterpot601@hotmail.com> wrote in message
news:zg4Ah.17451$Da4.9932@newsfe6-gui.ntli.net
[snip]
when you hear that patients who are actually in the
> surgery having their 5-min appointment will quite happily
> answer their phone and launch into a chat
> mid-consultation, you can understand the reasoning!
Not to mention the surgeons on the phone in the operating theatres whilst
still in the middle of somebody's innards..!
"Chris Davies" <chris-usenet@roaima.co.uk> wrote in message
news:kc79a4-cv9.ln1@news.roaima.co.uk
> Mark Jones Laptop2 <maj66@btinternet.com> wrote:
> > 2. If it was a Cinema or Library then fine [...]
>
> No, it's not fine. I take my phone with me to the cinema
> so that the babysitter can contact my wife and I in an
> emergency. It /is/ on vibrate, though, and I wouldn't
> answer it in the auditorium itself.
What did you do before mobiles..? If it was a real, genuine emergency, the
babysitter could ring the cinema and they could come and get you
discreetly, you having previously told them that you may receive a call in
an emergency and where to find you in the auditorium.
"Chris Davies" <chris-usenet@roaima.co.uk> wrote in message
news:kc79a4-cv9.ln1@news.roaima.co.uk...
> Mark Jones Laptop2 <maj66@btinternet.com> wrote:
>> 2. If it was a Cinema or Library then fine [...]
>
> No, it's not fine. I take my phone with me to the cinema so that the
> babysitter can contact my wife and I in an emergency. It /is/ on vibrate,
> though, and I wouldn't answer it in the auditorium itself.
>
> Chris
"Chris Davies" <chris-usenet@roaima.co.uk> wrote in message
> I take my phone with me to the cinema so that the babysitter can
> contact my wife and me [...]
Ivor Jones <ivor@despammed.invalid> wrote:
> What did you do before mobiles..?
Um, well, let me see. Travelled around the world, phoning back to
the UK only every couple of weeks to say we were still alive.
I don't see the relevance of your question, though.
> If it was a real, genuine emergency, the babysitter could ring the
> cinema and they could come and get you discreetly
The OP wasn't commenting on being contacted in a cinema 10+ years ago. I
could equally ask you what you did before VOIP allowed you to have many
lines to your home(?)/office, but it's irrelevant to the present day.
Having a mobile on vibrate means that the babysitter can contact me
directly instead of having to chance the cinema staff remembering my
request and being able to find me.
"Chris Davies" <chris-usenet@roaima.co.uk> wrote in message
news:mi1ba4-n9q.ln1@news.roaima.co.uk
> "Chris Davies" <chris-usenet@roaima.co.uk> wrote in
> message
> > I take my phone with me to the cinema so that the
> > babysitter can contact my wife and me [...]
>
> Ivor Jones <ivor@despammed.invalid> wrote:
> > What did you do before mobiles..?
>
> Um, well, let me see. Travelled around the world, phoning
> back to
> the UK only every couple of weeks to say we were still
> alive.
>
> I don't see the relevance of your question, though.
The relevance is the fact that people today seem to be totally unable to
function without mobile phones.
Think back to what you would do if you didn't have one and do that.
Ivor Jones <ivor@despammed.invalid> wrote:
> The relevance is the fact that people today seem to be totally unable to
> function without mobile phones.
If some people have a dependence on technology then that is their
lookout. How many people would object if they didn't have a TV / PC /
Internet connection / whatever for more than a few days?
> Think back to what you would do if you didn't have one and do that.
> Problem solved.
I didn't have children 10 years ago, but I do now. I didn't have a mobile
phone back then either; I do now. My preference is to have the phone
on, but switched such that it doesn't offend anyone else's experience
[of cinema]. Should I be contacted, I still believe that this would be
less intrusive for others than a member of staff trying to find me.
Supermarkets blocking phone signals? 
Linear Mode
