Large scale RF shielding...

[Don Y]

Homes, here, tend to be reasonably opaque to RF. OTA broadcasts
can only be received with a rooftop antenna (despite the fact
that it\'s only a few unobstructed miles to the transmitters).
Indoor FM reception is \"iffy\". GPSs can\'t get a fix (I\'ve tried
2 handheld units, 2 dash-mount plus the one built into the car).
Even the two \"atomic\" clocks that I have spend all of their
time \"looking for signal\" (or so they claim).

And *everyone* steps outside to use their cell phones. (OK,
maybe the neighborhood is a deadspot due to terrain -- despite
antennas being reasonably close by -- though I\'ve no way of
knowing who is \"operating\" each of them)

I.e., the \"problem\" isn\'t confined to our home.

This begs two *different* questions:
1. How to punch holes in <whatever> is attenuating the signal
2. How to identify the cause of the problem to be able to
(willingly) *reproduce* it in other places

Most homes are masonry - 8-12\" thick walls. Interior walls on
the perimeter are firred out with drywall coated with aluminum
foil (moisture barrier?). All internal wiring is overhead, plumbing
in the slab. Different types of roofing so I\'m unsure if there
is a common thread, there.

Ideally, there is a *cheap* way to get this sort of attenuation
that can be retrofitted to existing homes of different construction.

 

[Phil Allison]

Don WHY? wrote:
=============

Homes, here, tend to be reasonably opaque to RF. OTA broadcasts
can only be received with a rooftop antenna (despite the fact
that it\'s only a few unobstructed miles to the transmitters).
Indoor FM reception is \"iffy\". GPSs can\'t get a fix (I\'ve tried
2 handheld units, 2 dash-mount plus the one built into the car).
Even the two \"atomic\" clocks that I have spend all of their
time \"looking for signal\" (or so they claim).

And *everyone* steps outside to use their cell phones. (OK,
maybe the neighborhood is a deadspot due to terrain -- despite
antennas being reasonably close by -- though I\'ve no way of
knowing who is \"operating\" each of them)

** Like all of your trolls, the crucial facts are missing.

If the path to the transmitters is really \" unobstructed \" and short range, your story is 100% non credible.
What is the REAL story ?

BTW:
Do you wear a tin hat ?


....... Phil

 

[John Larkin]

On Thu, 5 May 2022 11:46:13 -0700, Don Y <blockedofcourse@foo.invalid>
wrote:

Homes, here, tend to be reasonably opaque to RF. OTA broadcasts
can only be received with a rooftop antenna (despite the fact
that it\'s only a few unobstructed miles to the transmitters).
Indoor FM reception is \"iffy\". GPSs can\'t get a fix (I\'ve tried
2 handheld units, 2 dash-mount plus the one built into the car).
Even the two \"atomic\" clocks that I have spend all of their
time \"looking for signal\" (or so they claim).

And *everyone* steps outside to use their cell phones. (OK,
maybe the neighborhood is a deadspot due to terrain -- despite
antennas being reasonably close by -- though I\'ve no way of
knowing who is \"operating\" each of them)

I.e., the \"problem\" isn\'t confined to our home.

This begs two *different* questions:
1. How to punch holes in <whatever> is attenuating the signal
2. How to identify the cause of the problem to be able to
(willingly) *reproduce* it in other places

Most homes are masonry - 8-12\" thick walls. Interior walls on
the perimeter are firred out with drywall coated with aluminum
foil (moisture barrier?). All internal wiring is overhead, plumbing
in the slab. Different types of roofing so I\'m unsure if there
is a common thread, there.

Ideally, there is a *cheap* way to get this sort of attenuation
that can be retrofitted to existing homes of different construction.

Must the the foil. What\'s strange is that it\'s really hard to build a
good EMI screen room.

One trick is to run a wire from outside (as a receive antenna) to
inside (as a radiator). I\'ve seen that done in tunnels.

--

If a man will begin with certainties, he shall end with doubts,
but if he will be content to begin with doubts he shall end in certainties.
Francis Bacon

 

[server]

John Larkin <jlarkin@highland_atwork_technology.com> wrote in
news:sfi87htnmuc8c1u3qrj87dltg6ng9468ji@4ax.com:

On Thu, 5 May 2022 11:46:13 -0700, Don Y
blockedofcourse@foo.invalid> wrote:

Homes, here, tend to be reasonably opaque to RF. OTA broadcasts
can only be received with a rooftop antenna (despite the fact
that it\'s only a few unobstructed miles to the transmitters).
Indoor FM reception is \"iffy\". GPSs can\'t get a fix (I\'ve tried
2 handheld units, 2 dash-mount plus the one built into the car).
Even the two \"atomic\" clocks that I have spend all of their
time \"looking for signal\" (or so they claim).

And *everyone* steps outside to use their cell phones. (OK,
maybe the neighborhood is a deadspot due to terrain -- despite
antennas being reasonably close by -- though I\'ve no way of
knowing who is \"operating\" each of them)

I.e., the \"problem\" isn\'t confined to our home.

This begs two *different* questions:
1. How to punch holes in <whatever> is attenuating the signal
2. How to identify the cause of the problem to be able to
(willingly) *reproduce* it in other places

Most homes are masonry - 8-12\" thick walls. Interior walls on
the perimeter are firred out with drywall coated with aluminum
foil (moisture barrier?). All internal wiring is overhead,
plumbing in the slab. Different types of roofing so I\'m unsure if
there is a common thread, there.

Ideally, there is a *cheap* way to get this sort of attenuation
that can be retrofitted to existing homes of different
construction.

Must the the foil. What\'s strange is that it\'s really hard to
build a good EMI screen room.

One trick is to run a wire from outside (as a receive antenna) to
inside (as a radiator). I\'ve seen that done in tunnels.

Yes. Try to build one and it leaks so bad you can \"hear\" a pin drop
onto a magnet halfway around the world.

This sounds more like cell towers that are turned way down on power
due to low utilization of that node.

I remember placing a lot of copper tape to make our quiet cage
\'clean\'. Have to have a pretty heavy tip on that solder iron too.

 

[Phil Hobbs]

John Larkin wrote:

On Thu, 5 May 2022 11:46:13 -0700, Don Y <blockedofcourse@foo.invalid
wrote:

Homes, here, tend to be reasonably opaque to RF. OTA broadcasts
can only be received with a rooftop antenna (despite the fact
that it\'s only a few unobstructed miles to the transmitters).
Indoor FM reception is \"iffy\". GPSs can\'t get a fix (I\'ve tried
2 handheld units, 2 dash-mount plus the one built into the car).
Even the two \"atomic\" clocks that I have spend all of their
time \"looking for signal\" (or so they claim).

And *everyone* steps outside to use their cell phones. (OK,
maybe the neighborhood is a deadspot due to terrain -- despite
antennas being reasonably close by -- though I\'ve no way of
knowing who is \"operating\" each of them)

I.e., the \"problem\" isn\'t confined to our home.

This begs two *different* questions:
1. How to punch holes in <whatever> is attenuating the signal
2. How to identify the cause of the problem to be able to
(willingly) *reproduce* it in other places

Most homes are masonry - 8-12\" thick walls. Interior walls on
the perimeter are firred out with drywall coated with aluminum
foil (moisture barrier?). All internal wiring is overhead, plumbing
in the slab. Different types of roofing so I\'m unsure if there
is a common thread, there.

Ideally, there is a *cheap* way to get this sort of attenuation
that can be retrofitted to existing homes of different construction.

Must the the foil. What\'s strange is that it\'s really hard to build a
good EMI screen room.

It\'s the wallpaper effect--it won\'t stick when you\'re putting it up, and
won\'t come off when you\'re taking it down.

40 dB loss is a pretty crappy screen room, but will reliably make a mess
of cell phone communications.

(We built a test jig out of a big beefy 5x9-inch aluminum die cast box
whose lid attaches with a screw in each corner. Turns out that the
RasPi inside communicates via wifi quite nicely.

One trick is to run a wire from outside (as a receive antenna) to
inside (as a radiator). I\'ve seen that done in tunnels.

Yup. People have made passive VHF repeaters for amateur radio by
putting antennas on each side of a mountain and just wiring them
together with coax.

Cheers

Phil Hobbs


--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510

http://electrooptical.net
http://hobbs-eo.com

 

[Clifford Heath]

On 6/5/22 12:08 pm, Phil Hobbs wrote:

John Larkin wrote:
On Thu, 5 May 2022 11:46:13 -0700, Don Y <blockedofcourse@foo.invalid
wrote:

Homes, here, tend to be reasonably opaque to RF.  OTA broadcasts
can only be received with a rooftop antenna (despite the fact
that it\'s only a few unobstructed miles to the transmitters).
Indoor FM reception is \"iffy\".  GPSs can\'t get a fix (I\'ve tried
2 handheld units, 2 dash-mount plus the one built into the car).
Even the two \"atomic\" clocks that I have spend all of their
time \"looking for signal\" (or so they claim).

And *everyone* steps outside to use their cell phones.  (OK,
maybe the neighborhood is a deadspot due to terrain -- despite
antennas being reasonably close by -- though I\'ve no way of
knowing who is \"operating\" each of them)

I.e., the \"problem\" isn\'t confined to our home.

This begs two *different* questions:
1.  How to punch holes in <whatever> is attenuating the signal
2.  How to identify the cause of the problem to be able to
     (willingly) *reproduce* it in other places

Most homes are masonry - 8-12\" thick walls.  Interior walls on
the perimeter are firred out with drywall coated with aluminum
foil (moisture barrier?).  All internal wiring is overhead, plumbing
in the slab.  Different types of roofing so I\'m unsure if there
is a common thread, there.

Ideally, there is a *cheap* way to get this sort of attenuation
that can be retrofitted to existing homes of different construction.

Must the the foil. What\'s strange is that it\'s really hard to build a
good EMI screen room.

It\'s the wallpaper effect--it won\'t stick when you\'re putting it up, and
won\'t come off when you\'re taking it down.

40 dB loss is a pretty crappy screen room, but will reliably make a mess
of cell phone communications.

(We built a test jig out of a big beefy 5x9-inch aluminum die cast box
whose lid attaches with a screw in each corner.  Turns out that the
RasPi inside communicates via wifi quite nicely.


One trick is to run a wire from outside (as a receive antenna) to
inside (as a radiator). I\'ve seen that done in tunnels.

Yup.  People have made passive VHF repeaters for amateur radio by
putting antennas on each side of a mountain and just wiring them
together with coax.

NASA uses a passive repeater like that for the moon landings,
to get signals from Honeysuckle Creek tracking station to the Deep Space
Network site at Tidbinbilla. They had a wired connection as well (just a
single telecoms cable pair), following the requirement for everything to
be double-redundant. There was a microwave link to Parkes somewhere too.

The repeater tower is probably still there:
<https://goo.gl/maps/Syw2AFNo6fxuqn97A>

There was also a collimating target for aligning the antenna down to the
south-west. It\'s all pretty deep in the mountains, for radio quietness.
The Orroral Valley orbital tracking site is south of Honeysuckle too.
All the structures down to ground level have been removed now, except at
Tidbinbilla.

Clifford Heath.

 

[Jan Panteltje]

On a sunny day (Thu, 5 May 2022 11:46:13 -0700) it happened Don Y
<blockedofcourse@foo.invalid> wrote in <t5162c$s9f$1@dont-email.me>:

Homes, here, tend to be reasonably opaque to RF. OTA broadcasts
can only be received with a rooftop antenna (despite the fact
that it\'s only a few unobstructed miles to the transmitters).
Indoor FM reception is \"iffy\". GPSs can\'t get a fix (I\'ve tried
2 handheld units, 2 dash-mount plus the one built into the car).
Even the two \"atomic\" clocks that I have spend all of their
time \"looking for signal\" (or so they claim).

And *everyone* steps outside to use their cell phones. (OK,
maybe the neighborhood is a deadspot due to terrain -- despite
antennas being reasonably close by -- though I\'ve no way of
knowing who is \"operating\" each of them)

I.e., the \"problem\" isn\'t confined to our home.

This begs two *different* questions:
1. How to punch holes in <whatever> is attenuating the signal
2. How to identify the cause of the problem to be able to
(willingly) *reproduce* it in other places

Most homes are masonry - 8-12\" thick walls. Interior walls on
the perimeter are firred out with drywall coated with aluminum
foil (moisture barrier?). All internal wiring is overhead, plumbing
in the slab. Different types of roofing so I\'m unsure if there
is a common thread, there.

Ideally, there is a *cheap* way to get this sort of attenuation
that can be retrofitted to existing homes of different construction.

Some double glazing also stops RF, I tried my satellite dish inside behind such a window,
almost no signal...

Solution, as the dedicated greens will know, is to live in a tent or what\'s it called \'wigwam\'?

Be glad all that RF is attenuated indoors, it interferes with the brain.
Some people get sick from it.
That said LOL I have been exposed ... a lot, So you see the bad effects it can have.

My 4G internet just uses an USB stick in the window, inserted in an Raspberry Pi programmed as router:
http://panteltje.com/pub/4G_toren_IMG_7385.JPG
Spaghetti is supposed to be in that vase..

phones works indoors here..
If not I would get a landline...
Even DVB-T2 (latest terrestrial TV) works with a simple indoors antenna:
http://panteltje.com/pub/DVB-T2_antenna_IXIMG_0757.JPG
transmitter is miles away....
GPS works, but better upstairs, not always enough sats for positioning downstairs.

Maybe you could get a simple signal strength meter and walk around the house to see where and what attenuates things?
Radio with signal strength indicator, I think even one of my phones
has a signal strength bar?

Depends on the frequency you want to check..
Spectrum analyzer, using a RTL-SDR stick will show a lot from about 20 MHz up to 1.4 GHz..
http://panteltje.com/panteltje/xpsa/index.html
lots of open source software for it, get a 1 ppm one from ebay for about 30 USD.
plug into you laptop with a 15 cm piece of wire as antenna, works perfectly.

 

[Jeff Layman]

On 05/05/2022 19:46, Don Y wrote:

Homes, here, tend to be reasonably opaque to RF. OTA broadcasts
can only be received with a rooftop antenna (despite the fact
that it\'s only a few unobstructed miles to the transmitters).
Indoor FM reception is \"iffy\". GPSs can\'t get a fix (I\'ve tried
2 handheld units, 2 dash-mount plus the one built into the car).
Even the two \"atomic\" clocks that I have spend all of their
time \"looking for signal\" (or so they claim).

And *everyone* steps outside to use their cell phones. (OK,
maybe the neighborhood is a deadspot due to terrain -- despite
antennas being reasonably close by -- though I\'ve no way of
knowing who is \"operating\" each of them)

I.e., the \"problem\" isn\'t confined to our home.

This begs two *different* questions:
1. How to punch holes in <whatever> is attenuating the signal
2. How to identify the cause of the problem to be able to
(willingly) *reproduce* it in other places

Most homes are masonry - 8-12\" thick walls. Interior walls on
the perimeter are firred out with drywall coated with aluminum
foil (moisture barrier?). All internal wiring is overhead, plumbing
in the slab. Different types of roofing so I\'m unsure if there
is a common thread, there.

Ideally, there is a *cheap* way to get this sort of attenuation
that can be retrofitted to existing homes of different construction.

As others have suggested, I\'d also go with the metal foil as the
problem, especially as it seems to cover the whole spectrum from a few
10s of kHz (radio clocks) to the GHz range of cellphones. Do you have
any wooden doors on the cellphone tower side of the house? Is the
cellphone signal level any better \"through\" those doors than through the
house walls? All bets are off if you have metal flyscreens over the doors!

You can get cellphone boosters which have an external antenna and carry
the signal indoors, but they would only help with cellphone frequencies.
Would an external long-wire antenna with a loop wrapped round your radio
clock help with that signal?

--

Jeff

 

[Martin Brown]

On 05/05/2022 19:46, Don Y wrote:

Homes, here, tend to be reasonably opaque to RF.  OTA broadcasts
can only be received with a rooftop antenna (despite the fact
that it\'s only a few unobstructed miles to the transmitters).
Indoor FM reception is \"iffy\".  GPSs can\'t get a fix (I\'ve tried
2 handheld units, 2 dash-mount plus the one built into the car).
Even the two \"atomic\" clocks that I have spend all of their
time \"looking for signal\" (or so they claim).

That\'s a bit surprising.

My house is solid wall three bricks thick and I still get enough RF in
through the windows for it not to be a problem. They are low emissivity
windows too now so I did wonder about it when they were replaced.

The only exception is DAB radio (crock of sh*t) and 2FA texts which
sometimes take forever to arrive (so that the website times out before
it arrives). Voice mobile calls are usually OK indoors.

Trying to get a 2FA code I sometime end up walking around the highest
part of the garden waving my phone high in the air to get signal.

And *everyone* steps outside to use their cell phones.  (OK,
maybe the neighborhood is a deadspot due to terrain -- despite
antennas being reasonably close by -- though I\'ve no way of
knowing who is \"operating\" each of them)

Is there no equivalent of this site in the USA?

https://www.signalchecker.co.uk

Quick overview of what is available and it has links to individual
mobile networks claims as to coverage at your location.

To give is a whirl put in a random postcode like TS1 1AA.
(that\'s a fairly non-descript northern city Middlesbrough)

M2 2AA is in Manchester with much better 5G coverage

SW1A 1AA is in London, PM\'s residence and is as good as it gets.

Or put your phone into engineering diagnostic mode (at your own risk)
and you can see carrier details and signal levels in real time then walk
round to local masts to see which is which. You might need to do it with
a few phones on different networks to get a full picture if they share.

I.e., the \"problem\" isn\'t confined to our home.

This begs two *different* questions:
1.  How to punch holes in <whatever> is attenuating the signal

Glass windows usually do that for you.

2.  How to identify the cause of the problem to be able to
    (willingly) *reproduce* it in other places

Most homes are masonry - 8-12\" thick walls.  Interior walls on
the perimeter are firred out with drywall coated with aluminum
foil (moisture barrier?).  All internal wiring is overhead, plumbing
in the slab.  Different types of roofing so I\'m unsure if there
is a common thread, there.

Ideally, there is a *cheap* way to get this sort of attenuation
that can be retrofitted to existing homes of different construction.

I\'d have thought that a thin layer of aluminium foil or conductive paint
would go a long way to providing a decent level of RF attenuation.

ISTR if you are serious about it then you pretty much have to have
welded sheet metal construction and beryllium spring copper contacts on
all the doors (usually only one double width door on a Faraday cage
room) and fancy suppressors on any cables in or out.

Might be easier to start out with a Ford transit van than a house.

High end car theft gangs in Belgium did a pretty good job with lining a
largish HVG with supermarket grade aluminium foil and if memory serves
lead flashing seals on the opening joints. Good enough Faraday cage to
steal high end cars with notional satellite tracking on them anyway.

--
Regards,
Martin Brown

 

[server]

On Thu, 5 May 2022 22:08:06 -0400, Phil Hobbs
<pcdhSpamMeSenseless@electrooptical.net> wrote:

John Larkin wrote:
On Thu, 5 May 2022 11:46:13 -0700, Don Y <blockedofcourse@foo.invalid
wrote:

Homes, here, tend to be reasonably opaque to RF. OTA broadcasts
can only be received with a rooftop antenna (despite the fact
that it\'s only a few unobstructed miles to the transmitters).
Indoor FM reception is \"iffy\". GPSs can\'t get a fix (I\'ve tried
2 handheld units, 2 dash-mount plus the one built into the car).
Even the two \"atomic\" clocks that I have spend all of their
time \"looking for signal\" (or so they claim).

And *everyone* steps outside to use their cell phones. (OK,
maybe the neighborhood is a deadspot due to terrain -- despite
antennas being reasonably close by -- though I\'ve no way of
knowing who is \"operating\" each of them)

I.e., the \"problem\" isn\'t confined to our home.

This begs two *different* questions:
1. How to punch holes in <whatever> is attenuating the signal
2. How to identify the cause of the problem to be able to
(willingly) *reproduce* it in other places

Most homes are masonry - 8-12\" thick walls. Interior walls on
the perimeter are firred out with drywall coated with aluminum
foil (moisture barrier?). All internal wiring is overhead, plumbing
in the slab. Different types of roofing so I\'m unsure if there
is a common thread, there.

Ideally, there is a *cheap* way to get this sort of attenuation
that can be retrofitted to existing homes of different construction.

Must the the foil. What\'s strange is that it\'s really hard to build a
good EMI screen room.

It\'s the wallpaper effect--it won\'t stick when you\'re putting it up, and
won\'t come off when you\'re taking it down.

40 dB loss is a pretty crappy screen room, but will reliably make a mess
of cell phone communications.

(We built a test jig out of a big beefy 5x9-inch aluminum die cast box
whose lid attaches with a screw in each corner. Turns out that the
RasPi inside communicates via wifi quite nicely.


One trick is to run a wire from outside (as a receive antenna) to
inside (as a radiator). I\'ve seen that done in tunnels.

Yup. People have made passive VHF repeaters for amateur radio by
putting antennas on each side of a mountain and just wiring them
together with coax.

Cheers

Phil Hobbs

RF is hard to believe. My key fob will unlock my car from half a block
away. We get pictures back from Jupiter. Seems improbable.



--

Anybody can count to one.

- Robert Widlar

 

[Jeroen Belleman]

On 2022-05-06 16:08, jlarkin@highlandsniptechnology.com wrote:

On Thu, 5 May 2022 22:08:06 -0400, Phil Hobbs
pcdhSpamMeSenseless@electrooptical.net> wrote:

John Larkin wrote:
On Thu, 5 May 2022 11:46:13 -0700, Don Y <blockedofcourse@foo.invalid
wrote:

Homes, here, tend to be reasonably opaque to RF. OTA broadcasts
can only be received with a rooftop antenna (despite the fact
that it\'s only a few unobstructed miles to the transmitters).
Indoor FM reception is \"iffy\". GPSs can\'t get a fix (I\'ve tried
2 handheld units, 2 dash-mount plus the one built into the car).
Even the two \"atomic\" clocks that I have spend all of their
time \"looking for signal\" (or so they claim).

And *everyone* steps outside to use their cell phones. (OK,
maybe the neighborhood is a deadspot due to terrain -- despite
antennas being reasonably close by -- though I\'ve no way of
knowing who is \"operating\" each of them)

I.e., the \"problem\" isn\'t confined to our home.

This begs two *different* questions:
1. How to punch holes in <whatever> is attenuating the signal
2. How to identify the cause of the problem to be able to
(willingly) *reproduce* it in other places

Most homes are masonry - 8-12\" thick walls. Interior walls on
the perimeter are firred out with drywall coated with aluminum
foil (moisture barrier?). All internal wiring is overhead, plumbing
in the slab. Different types of roofing so I\'m unsure if there
is a common thread, there.

Ideally, there is a *cheap* way to get this sort of attenuation
that can be retrofitted to existing homes of different construction.

Must the the foil. What\'s strange is that it\'s really hard to build a
good EMI screen room.

It\'s the wallpaper effect--it won\'t stick when you\'re putting it up, and
won\'t come off when you\'re taking it down.

40 dB loss is a pretty crappy screen room, but will reliably make a mess
of cell phone communications.

(We built a test jig out of a big beefy 5x9-inch aluminum die cast box
whose lid attaches with a screw in each corner. Turns out that the
RasPi inside communicates via wifi quite nicely.


One trick is to run a wire from outside (as a receive antenna) to
inside (as a radiator). I\'ve seen that done in tunnels.

Yup. People have made passive VHF repeaters for amateur radio by
putting antennas on each side of a mountain and just wiring them
together with coax.

Cheers

Phil Hobbs

RF is hard to believe. My key fob will unlock my car from half a block
away. We get pictures back from Jupiter. Seems improbable.

It screams very loudly in a medium we cannot perceive. Imagine what
it would be like if we could hear RF.

Jeroen Belleman

 

[server]

On Fri, 06 May 2022 17:27:55 +0200, Jeroen Belleman
<jeroen@nospam.please> wrote:

On 2022-05-06 16:08, jlarkin@highlandsniptechnology.com wrote:
On Thu, 5 May 2022 22:08:06 -0400, Phil Hobbs
pcdhSpamMeSenseless@electrooptical.net> wrote:

John Larkin wrote:
On Thu, 5 May 2022 11:46:13 -0700, Don Y <blockedofcourse@foo.invalid
wrote:

Homes, here, tend to be reasonably opaque to RF. OTA broadcasts
can only be received with a rooftop antenna (despite the fact
that it\'s only a few unobstructed miles to the transmitters).
Indoor FM reception is \"iffy\". GPSs can\'t get a fix (I\'ve tried
2 handheld units, 2 dash-mount plus the one built into the car).
Even the two \"atomic\" clocks that I have spend all of their
time \"looking for signal\" (or so they claim).

And *everyone* steps outside to use their cell phones. (OK,
maybe the neighborhood is a deadspot due to terrain -- despite
antennas being reasonably close by -- though I\'ve no way of
knowing who is \"operating\" each of them)

I.e., the \"problem\" isn\'t confined to our home.

This begs two *different* questions:
1. How to punch holes in <whatever> is attenuating the signal
2. How to identify the cause of the problem to be able to
(willingly) *reproduce* it in other places

Most homes are masonry - 8-12\" thick walls. Interior walls on
the perimeter are firred out with drywall coated with aluminum
foil (moisture barrier?). All internal wiring is overhead, plumbing
in the slab. Different types of roofing so I\'m unsure if there
is a common thread, there.

Ideally, there is a *cheap* way to get this sort of attenuation
that can be retrofitted to existing homes of different construction.

Must the the foil. What\'s strange is that it\'s really hard to build a
good EMI screen room.

It\'s the wallpaper effect--it won\'t stick when you\'re putting it up, and
won\'t come off when you\'re taking it down.

40 dB loss is a pretty crappy screen room, but will reliably make a mess
of cell phone communications.

(We built a test jig out of a big beefy 5x9-inch aluminum die cast box
whose lid attaches with a screw in each corner. Turns out that the
RasPi inside communicates via wifi quite nicely.


One trick is to run a wire from outside (as a receive antenna) to
inside (as a radiator). I\'ve seen that done in tunnels.

Yup. People have made passive VHF repeaters for amateur radio by
putting antennas on each side of a mountain and just wiring them
together with coax.

Cheers

Phil Hobbs

RF is hard to believe. My key fob will unlock my car from half a block
away. We get pictures back from Jupiter. Seems improbable.




It screams very loudly in a medium we cannot perceive. Imagine what
it would be like if we could hear RF.

Jeroen Belleman

From the roof of Highland World Headquarters I count about 40 dishes
visible with my terrible eyesight. Wouldn\'t it be cool if the beams
glowed at night.

Our internet service is a small dish. We paid for 50+50 Mbps and get
500+500.



--

Anybody can count to one.

- Robert Widlar

 

[Joe Gwinn]

On Fri, 6 May 2022 10:46:00 +0100, Martin Brown
<\'\'\'newspam\'\'\'@nonad.co.uk> wrote:

On 05/05/2022 19:46, Don Y wrote:
Homes, here, tend to be reasonably opaque to RF.  OTA broadcasts
can only be received with a rooftop antenna (despite the fact
that it\'s only a few unobstructed miles to the transmitters).
Indoor FM reception is \"iffy\".  GPSs can\'t get a fix (I\'ve tried
2 handheld units, 2 dash-mount plus the one built into the car).
Even the two \"atomic\" clocks that I have spend all of their
time \"looking for signal\" (or so they claim).

That\'s a bit surprising.

My house is solid wall three bricks thick and I still get enough RF in
through the windows for it not to be a problem. They are low emissivity
windows too now so I did wonder about it when they were replaced.

The only exception is DAB radio (crock of sh*t) and 2FA texts which
sometimes take forever to arrive (so that the website times out before
it arrives). Voice mobile calls are usually OK indoors.

Trying to get a 2FA code I sometime end up walking around the highest
part of the garden waving my phone high in the air to get signal.

And *everyone* steps outside to use their cell phones.  (OK,
maybe the neighborhood is a deadspot due to terrain -- despite
antennas being reasonably close by -- though I\'ve no way of
knowing who is \"operating\" each of them)

Is there no equivalent of this site in the USA?

https://www.signalchecker.co.uk

There are a number of them, but I don\'t know which ones are most
reliable.

Quick overview of what is available and it has links to individual
mobile networks claims as to coverage at your location.

To give is a whirl put in a random postcode like TS1 1AA.
(that\'s a fairly non-descript northern city Middlesbrough)

M2 2AA is in Manchester with much better 5G coverage

SW1A 1AA is in London, PM\'s residence and is as good as it gets.

Or put your phone into engineering diagnostic mode (at your own risk)
and you can see carrier details and signal levels in real time then walk
round to local masts to see which is which. You might need to do it with
a few phones on different networks to get a full picture if they share.

I had not heard of this \"engineering diagnostic mode\". Turns out that
my iPhone 8 supports it. I didn\'t see anything dangerous, although I
didn\'t look all that hard.

I.e., the \"problem\" isn\'t confined to our home.

This begs two *different* questions:
1.  How to punch holes in <whatever> is attenuating the signal

Glass windows usually do that for you.

Yes, unless they have some kind of conductive film. Some do.

2.  How to identify the cause of the problem to be able to
    (willingly) *reproduce* it in other places

Most homes are masonry - 8-12\" thick walls.  Interior walls on
the perimeter are firred out with drywall coated with aluminum
foil (moisture barrier?).  All internal wiring is overhead, plumbing
in the slab.  Different types of roofing so I\'m unsure if there
is a common thread, there.

That kind of construction is not common in the US.

But my house is stucco over expanded metal lath, so it does a pretty
good job of blocking cellphone signals.

Ideally, there is a *cheap* way to get this sort of attenuation
that can be retrofitted to existing homes of different construction.

I\'d have thought that a thin layer of aluminium foil or conductive paint
would go a long way to providing a decent level of RF attenuation.

Yes, this is one way many big shielded rooms are done. The foil is
quite thick, and there are multiple overlapping sheets, so the
building can expand and contract with seasons without breaking the
shielding.

All wall penetrations are filtered and the filter bonded to the shield
wall.

The floor is more commonly overlapping sheets of thin galvanized
steel.

ISTR if you are serious about it then you pretty much have to have
welded sheet metal construction and beryllium spring copper contacts on
all the doors (usually only one double width door on a Faraday cage
room) and fancy suppressors on any cables in or out.

Yes.

Might be easier to start out with a Ford transit van than a house.

High end car theft gangs in Belgium did a pretty good job with lining a
largish HVG with supermarket grade aluminium foil and if memory serves
lead flashing seals on the opening joints. Good enough Faraday cage to
steal high end cars with notional satellite tracking on them anyway.

Cute. I assume that HVG is some kind of lorry.

Where do they take the cars to? The tracking will start working once
delivered and out in the open, unless they are able to disable all
possibilities. So I\'m assuming that it is some place without
extradition.

Joe Gwinn

 

[Don Y]

On 5/6/2022 2:46 AM, Martin Brown wrote:

On 05/05/2022 19:46, Don Y wrote:
Homes, here, tend to be reasonably opaque to RF. OTA broadcasts
can only be received with a rooftop antenna (despite the fact
that it\'s only a few unobstructed miles to the transmitters).
Indoor FM reception is \"iffy\". GPSs can\'t get a fix (I\'ve tried
2 handheld units, 2 dash-mount plus the one built into the car).
Even the two \"atomic\" clocks that I have spend all of their
time \"looking for signal\" (or so they claim).

That\'s a bit surprising.

My house is solid wall three bricks thick and I still get enough RF in through
the windows for it not to be a problem. They are low emissivity windows too now
so I did wonder about it when they were replaced.

The only exception is DAB radio (crock of sh*t) and 2FA texts which sometimes
take forever to arrive (so that the website times out before it arrives). Voice
mobile calls are usually OK indoors.

Trying to get a 2FA code I sometime end up walking around the highest part of
the garden waving my phone high in the air to get signal.

We only have views of the horizon through our windows. Most tend to have very
*deep* \"coverings\" (like porches) to block the sunlight from entering the house
when overhead. E.g., I can\'t see \"overhead sky\" while indoors. Instead, we
see other neighbors\' homes.

To get a GPS fix, I have to be outside. Likewise, while garaged, the car
doesn\'t know where it is -- beyond remembering its last position. I\'ve
tried this with two (similar) handhelds -- an eTrex Vista and an eTrex
Magellan (hacked to power from an external DC source) -- which I imagine are
very similar in design (?). Likewise, a pair of \"dash mount\" Garmins -- a
Nuvi 260W and a Nuvi 750 that also suggest some similarities between
themselves.

In each case, I set the UUT (only one at a time!) in the center of the living
room floor (the room with the least bit of RFI and nothing on the roof, above).
I waited 30 minutes for a fix. Then, moved on to the next unit. Nada.
Yet all will quickly acquire satellites and yield a fix within a minute or
two of being clear of the building. (84 seconds for the Vista, just now,
from being powered on from a state where \"no batteries installed\")

I suspect there\'s a buttload of RFI in most modern homes -- computers, CFL/LED
lights, dimmers, electronic appliances, etc. -- that contributes to poorer
reception.

And *everyone* steps outside to use their cell phones. (OK,
maybe the neighborhood is a deadspot due to terrain -- despite
antennas being reasonably close by -- though I\'ve no way of
knowing who is \"operating\" each of them)

Is there no equivalent of this site in the USA?

https://www.signalchecker.co.uk

Dunno. I don\'t use a cell phone for communications; I use them as
clocks, PMPs, cameras, TELNET/HTTP terminals... anything BUT a phone!
The idea of people being able to pester me at THEIR convenience,
regardless of where I am or what I am doing is anathema to me!
\"Send me an email, I\'ll get back to you at MY convenience!\" (and,
of course, THEY can reply to that at THEIR convenience)

My cell phone observations come from noticing the behaviors of my
neighbors -- who all step outside to take calls. If they were all
having clandestine \"affairs\" and didn\'t want their spouses to know,
I could understand bearing the \"cost\" of doing that. In the winter,
this is possibly understandable (nice weather) but silly from
~May thru ~Sept (our first 100F day was a week or so ago).

I\'ve no idea as to which carriers they use -- nor the operators
of the nearest cell towers (I can see at least three of them
within ~0.75 mi of my home... not counting others that may be
less noticeable -- or, located away from the roads I typically
travel). But, the topography, locally, is pretty irregular;
some of the antennae are actually *below* me in elevation (so,
I see their signal *through* scores of homes) others above.

There\'s a site that lists antennae/towers in the area -- it
claims 33 towers and 200+ antennae within 3 miles of my location
(no idea why it settled on that 3 mi figure). But, I notice that
it has no record of the three towers that I know for a fact to
be present! <shrug>

Quick overview of what is available and it has links to individual mobile
networks claims as to coverage at your location.

To give is a whirl put in a random postcode like TS1 1AA.
(that\'s a fairly non-descript northern city Middlesbrough)

M2 2AA is in Manchester with much better 5G coverage

SW1A 1AA is in London, PM\'s residence and is as good as it gets.

Or put your phone into engineering diagnostic mode (at your own risk) and you
can see carrier details and signal levels in real time then walk round to local
masts to see which is which. You might need to do it with a few phones on
different networks to get a full picture if they share.

I\'m not that interested :> My interest lies in sorting out what
construction characteristics have had the side-effect of *hindering*
reception -- with an eye towards using those (presumably inexpensive,
run-of-the-mill) approaches to attenuate interference between adjacent
\"RF domains\" (think apartment house, hotel, resort, office building,
etc. where you can expect folks to be operating their own kit
\"very close\" to \"your NONEXCLUSIVE RF-space\")

I.e., the \"problem\" isn\'t confined to our home.

This begs two *different* questions:
1. How to punch holes in <whatever> is attenuating the signal

Glass windows usually do that for you.

One side of the house is essentially \"all/mostly glass\" (floor
to ceiling). Another side has a single small window. The
third has just two windows while the last has *none*.

And, windows only look *out*, not up.

I suspect WWV (our time reference) is problematic due to our
location in the \"RF shadow\" of the nearby mountain range
(it\'s a 6000 ft change in elevation beginning just north of
our location; i.e., we are in the low spot of the valley).

OTOH, I don\'t understand why OTA broadcasts (TV/radio) are
so problematic. If I had a powerful enough laser, I could
illuminate the 5 towers atop that mountain without the beam
touching anything along the way (\"unobstructed\").

If I drop the antennae (from the roof) into the house at the
same points (i.e., so the azimuth to the towers is unchanged
and the elevation only slightly so), I\'ll lose most of the signal.
I.e., the pathlength has only increased by a few *feet*, no
obstructions have been introduced -- just the structure of the
house.

2. How to identify the cause of the problem to be able to
(willingly) *reproduce* it in other places

Most homes are masonry - 8-12\" thick walls. Interior walls on
the perimeter are firred out with drywall coated with aluminum
foil (moisture barrier?). All internal wiring is overhead, plumbing
in the slab. Different types of roofing so I\'m unsure if there
is a common thread, there.

Ideally, there is a *cheap* way to get this sort of attenuation
that can be retrofitted to existing homes of different construction.

I\'d have thought that a thin layer of aluminium foil or conductive paint would
go a long way to providing a decent level of RF attenuation.

That seems to explain many of the \"problems\", here. Had the masonry walls
been the issue, then that would be more challenging to reproduce, elsewhere.

E.g., if a builder can substitute foil-clad drywall for regular drywall
and pick up that level of attenuation, it suggests a minor/inexpensive
change in construction can help tamp down RF sources from neighboring
offices, apartments, suites, businesses, etc. And, something functionally
similar to buffer signals coming through floors/ceilings (think 3D).

ISTR if you are serious about it then you pretty much have to have welded sheet
metal construction and beryllium spring copper contacts on all the doors
(usually only one double width door on a Faraday cage room) and fancy
suppressors on any cables in or out.

Not interested in building a Faraday cage. Rather, would like to be able to
reduce the \"interference\" caused by nearby users who happen to be using
the same sort of kit. Without having to force them (FCC) to take
extraordinary measures to tamp down their emissions.

Might be easier to start out with a Ford transit van than a house.

High end car theft gangs in Belgium did a pretty good job with lining a largish
HVG with supermarket grade aluminium foil and if memory serves lead flashing
seals on the opening joints. Good enough Faraday cage to steal high end cars
with notional satellite tracking on them anyway.

One would think they would sort out where the antennae are located in each
model and simply disable it BEFORE driving off with the goods! Or, pull power.

 

[Don Y]

On 5/6/2022 9:31 AM, Joe Gwinn wrote:

2. How to identify the cause of the problem to be able to
(willingly) *reproduce* it in other places

Most homes are masonry - 8-12\" thick walls. Interior walls on
the perimeter are firred out with drywall coated with aluminum
foil (moisture barrier?). All internal wiring is overhead, plumbing
in the slab. Different types of roofing so I\'m unsure if there
is a common thread, there.

That kind of construction is not common in the US.

Depends on which part of the country you\'re located. Here, wooden-framed
homes are an exception. I\'ve never encountered a home with a basement.
Attic spaces are solely to decorate the \"elevation\" (roof pitch is too
low due to lack of snow carrying requirement).

Some adobe and straw-bale homes have walls 18\" thick.

But my house is stucco over expanded metal lath, so it does a pretty
good job of blocking cellphone signals.

Stucco over masonry, here. Stucco over lath over wood for framed
portions of homes (e.g., exterior wet walls).

High end car theft gangs in Belgium did a pretty good job with lining a
largish HVG with supermarket grade aluminium foil and if memory serves
lead flashing seals on the opening joints. Good enough Faraday cage to
steal high end cars with notional satellite tracking on them anyway.

Cute. I assume that HVG is some kind of lorry.

Where do they take the cars to? The tracking will start working once
delivered and out in the open, unless they are able to disable all
possibilities. So I\'m assuming that it is some place without
extradition.

Or, part them out before they can be found.

Here, a stolen car is in MX in less than an hour. Even cars that have
been legitimately *sold* may never see a formal title transfer (e.g.,
if the buyer intends to use it in a crime; think smuggling).

 

[Don Y]

On 5/6/2022 12:51 AM, Jeff Layman wrote:

On 05/05/2022 19:46, Don Y wrote:
Homes, here, tend to be reasonably opaque to RF. OTA broadcasts
can only be received with a rooftop antenna (despite the fact
that it\'s only a few unobstructed miles to the transmitters).
Indoor FM reception is \"iffy\". GPSs can\'t get a fix (I\'ve tried
2 handheld units, 2 dash-mount plus the one built into the car).
Even the two \"atomic\" clocks that I have spend all of their
time \"looking for signal\" (or so they claim).

And *everyone* steps outside to use their cell phones. (OK,
maybe the neighborhood is a deadspot due to terrain -- despite
antennas being reasonably close by -- though I\'ve no way of
knowing who is \"operating\" each of them)

I.e., the \"problem\" isn\'t confined to our home.

This begs two *different* questions:
1. How to punch holes in <whatever> is attenuating the signal
2. How to identify the cause of the problem to be able to
(willingly) *reproduce* it in other places

Most homes are masonry - 8-12\" thick walls. Interior walls on
the perimeter are firred out with drywall coated with aluminum
foil (moisture barrier?). All internal wiring is overhead, plumbing
in the slab. Different types of roofing so I\'m unsure if there
is a common thread, there.

Ideally, there is a *cheap* way to get this sort of attenuation
that can be retrofitted to existing homes of different construction.

As others have suggested, I\'d also go with the metal foil as the problem,

and SOLUTION! :>

especially as it seems to cover the whole spectrum from a few 10s of kHz (radio
clocks) to the GHz range of cellphones. Do you have any wooden doors on the
cellphone tower side of the house? Is the cellphone signal level any better
\"through\" those doors than through the house walls? All bets are off if you
have metal flyscreens over the doors!

Dunno. As I said elsewhere, *I* don\'t use cellular comms. The *cordless*
phones work everywhere in the house so we have no problem. But, friends
and neighbors seem to resort to \"stepping outside\" when they have to make
a call of any duration.

I suspect they must keep their phones located \"in a sweet spot\" indoors
lest they miss calls/texts (?). Or, resort to post-processing calls
by checking their voicemail (apparently, calls are intercepted thusly
in relatively short order... do they have to \"run\" to answer the phone
sited in that \"sweet spot\"? -- we have \"extensions\" throughout the house)

You can get cellphone boosters which have an external antenna and carry the
signal indoors, but they would only help with cellphone frequencies. Would an
external long-wire antenna with a loop wrapped round your radio clock help with
that signal?

I suspect it will have to be addressed by siting the antenna in a \"good
location\", much like the OTA services (which folks may or may not use).
I\'m replacing it with an SDR so I can handle several different comm needs
with a single radio. E.g., I only need a \"time update\" every month or two
as I discipline my local \"wall clock\" with the AC mains. And, most folks
don\'t worry about the accuracy of time to anything finer-grained than \"a couple
of minutes\" -- largely because they are at the mercy of other folks\' notion
of \"current time\" in most interactions! If your boss thinks it\'s 8:03 when
you show up for that 8:00 meeting, it doesn\'t matter if you pull out your
cesium reference and \"prove\" to him that it\'s really 7:59 -- he\'ll still
consider you late (and a wise-ass to boot!) Likewise, the airline decides
when the 9:00 flight departs.

[You only need better accuracy if you *know* -- e.g., contractually -- what
reference the other party will be relying upon. And, need finer-grained
synchronization only if the parties that must agree on a common time
require such. E.g., most computer networks are fine with 1 second or
worse as different machines are rarely needing to share a notion of
time beyond what their users expect (the file server imposes its notion
of \"now\" when you access/create one of its resources, regardless of
what time YOU -- or your computer -- think it may be!) OTOH, if you have
multiple SEPARATE processors working on a common problem, then tighter
synchronization may be required -- if only to order observations and
actions in time (A did something at A\'s notion of time and B did something
at B\'s notion of time; which came first? Especially as processors get
faster)]

So, check the time at some \"idle\" time of day/night. Use the SDR for
other purposes at other times (listening for pagers, door openers,
broadcast radio, etc.)

 

[Phil Hobbs]

Jeroen Belleman wrote:

On 2022-05-06 16:08, jlarkin@highlandsniptechnology.com wrote:
On Thu, 5 May 2022 22:08:06 -0400, Phil Hobbs
pcdhSpamMeSenseless@electrooptical.net> wrote:

John Larkin wrote:
On Thu, 5 May 2022 11:46:13 -0700, Don Y <blockedofcourse@foo.invalid
wrote:

Homes, here, tend to be reasonably opaque to RF.  OTA broadcasts
can only be received with a rooftop antenna (despite the fact
that it\'s only a few unobstructed miles to the transmitters).
Indoor FM reception is \"iffy\".  GPSs can\'t get a fix (I\'ve tried
2 handheld units, 2 dash-mount plus the one built into the car).
Even the two \"atomic\" clocks that I have spend all of their
time \"looking for signal\" (or so they claim).

And *everyone* steps outside to use their cell phones.  (OK,
maybe the neighborhood is a deadspot due to terrain -- despite
antennas being reasonably close by -- though I\'ve no way of
knowing who is \"operating\" each of them)

I.e., the \"problem\" isn\'t confined to our home.

This begs two *different* questions:
1.  How to punch holes in <whatever> is attenuating the signal
2.  How to identify the cause of the problem to be able to
      (willingly) *reproduce* it in other places

Most homes are masonry - 8-12\" thick walls.  Interior walls on
the perimeter are firred out with drywall coated with aluminum
foil (moisture barrier?).  All internal wiring is overhead, plumbing
in the slab.  Different types of roofing so I\'m unsure if there
is a common thread, there.

Ideally, there is a *cheap* way to get this sort of attenuation
that can be retrofitted to existing homes of different construction.

Must the the foil. What\'s strange is that it\'s really hard to build a
good EMI screen room.

It\'s the wallpaper effect--it won\'t stick when you\'re putting it up, and
won\'t come off when you\'re taking it down.

40 dB loss is a pretty crappy screen room, but will reliably make a mess
of cell phone communications.

(We built a test jig out of a big beefy 5x9-inch aluminum die cast box
whose lid attaches with a screw in each corner.  Turns out that the
RasPi inside communicates via wifi quite nicely.


One trick is to run a wire from outside (as a receive antenna) to
inside (as a radiator). I\'ve seen that done in tunnels.

Yup.  People have made passive VHF repeaters for amateur radio by
putting antennas on each side of a mountain and just wiring them
together with coax.

Cheers

Phil Hobbs

RF is hard to believe. My key fob will unlock my car from half a block
away. We get pictures back from Jupiter. Seems improbable.




It screams very loudly in a medium we cannot perceive. Imagine what
it would be like if we could hear RF.

Jeroen Belleman

The main thing is the ease of getting huge intercepted areas with a
single pair of wires (i.e. one port), and a contributing thing is the
energy per photon.

The etendue (area*solid angle product) of a single electromagnetic mode is

E = lambda**2 / 2.

If you need more etendue than that, i.e. either a wider acceptance angle
or more intercepted arear antenna\'s throughput is higher than that, you
have to use either multiple ports or incoherent detection. The SNR
tradeoff involved in going to much shorter wavelength is fairly
heartbreaking.

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510

http://electrooptical.net
http://hobbs-eo.com

 

[Rich S]

On Thursday, May 5, 2022 at 6:46:43 PM UTC, Don Y wrote:

Homes, here, tend to be reasonably opaque to RF. OTA broadcasts
can only be received with a rooftop antenna (despite the fact
that it\'s only a few unobstructed miles to the transmitters).
Indoor FM reception is \"iffy\". GPSs can\'t get a fix (I\'ve tried
2 handheld units, 2 dash-mount plus the one built into the car).
Even the two \"atomic\" clocks that I have spend all of their
time \"looking for signal\" (or so they claim).

And *everyone* steps outside to use their cell phones. (OK,
maybe the neighborhood is a deadspot due to terrain -- despite
antennas being reasonably close by -- though I\'ve no way of
knowing who is \"operating\" each of them)

I.e., the \"problem\" isn\'t confined to our home.

This begs two *different* questions:
1. How to punch holes in <whatever> is attenuating the signal
2. How to identify the cause of the problem to be able to
(willingly) *reproduce* it in other places

Most homes are masonry - 8-12\" thick walls. Interior walls on
the perimeter are firred out with drywall coated with aluminum
foil (moisture barrier?). All internal wiring is overhead, plumbing
in the slab. Different types of roofing so I\'m unsure if there
is a common thread, there.

Ideally, there is a *cheap* way to get this sort of attenuation
that can be retrofitted to existing homes of different construction.

uh, these homes lack windows?
Last I heard, glass is transparent for RF

 

[Rich S]

On Thursday, May 5, 2022 at 6:46:43 PM UTC, Don Y wrote:

Homes, here, tend to be reasonably opaque to RF. OTA broadcasts
can only be received with a rooftop antenna (despite the fact
that it\'s only a few unobstructed miles to the transmitters).
Indoor FM reception is \"iffy\". GPSs can\'t get a fix (I\'ve tried
2 handheld units, 2 dash-mount plus the one built into the car).
Even the two \"atomic\" clocks that I have spend all of their
time \"looking for signal\" (or so they claim).

And *everyone* steps outside to use their cell phones. (OK,
maybe the neighborhood is a deadspot due to terrain -- despite
antennas being reasonably close by -- though I\'ve no way of
knowing who is \"operating\" each of them)

I.e., the \"problem\" isn\'t confined to our home.

This begs two *different* questions:
1. How to punch holes in <whatever> is attenuating the signal
2. How to identify the cause of the problem to be able to
(willingly) *reproduce* it in other places

Most homes are masonry - 8-12\" thick walls. Interior walls on
the perimeter are firred out with drywall coated with aluminum
foil (moisture barrier?). All internal wiring is overhead, plumbing
in the slab. Different types of roofing so I\'m unsure if there
is a common thread, there.

Ideally, there is a *cheap* way to get this sort of attenuation
that can be retrofitted to existing homes of different construction.

Re \"1. How to punch holes in <whatever> is attenuating the signal \"
These homes do not have windows?
Last I heard, glass is transparent over a wide EM
spectrum including RF...
= RS

 

[John Walliker]

On Friday, 6 May 2022 at 19:03:19 UTC+1, Rich S wrote:

On Thursday, May 5, 2022 at 6:46:43 PM UTC, Don Y wrote:
Homes, here, tend to be reasonably opaque to RF. OTA broadcasts
can only be received with a rooftop antenna (despite the fact
that it\'s only a few unobstructed miles to the transmitters).
Indoor FM reception is \"iffy\". GPSs can\'t get a fix (I\'ve tried
2 handheld units, 2 dash-mount plus the one built into the car).
Even the two \"atomic\" clocks that I have spend all of their
time \"looking for signal\" (or so they claim).

And *everyone* steps outside to use their cell phones. (OK,
maybe the neighborhood is a deadspot due to terrain -- despite
antennas being reasonably close by -- though I\'ve no way of
knowing who is \"operating\" each of them)

I.e., the \"problem\" isn\'t confined to our home.

This begs two *different* questions:
1. How to punch holes in <whatever> is attenuating the signal
2. How to identify the cause of the problem to be able to
(willingly) *reproduce* it in other places

Most homes are masonry - 8-12\" thick walls. Interior walls on
the perimeter are firred out with drywall coated with aluminum
foil (moisture barrier?). All internal wiring is overhead, plumbing
in the slab. Different types of roofing so I\'m unsure if there
is a common thread, there.

Ideally, there is a *cheap* way to get this sort of attenuation
that can be retrofitted to existing homes of different construction.
Re \"1. How to punch holes in <whatever> is attenuating the signal \"
These homes do not have windows?
Last I heard, glass is transparent over a wide EM
spectrum including RF...

Not necessarily when it has a thin metal coating to reflect infra-red
radiation. Such glass is mandatory for all new windows here.

John