Which app do you use to scan/debug GSM/CDMA cellular tower s

[JF Mezei]

On 2017-02-17 14:44, nospam wrote:

> t-mobile's coverage is steadily getting *better*, not worse.

Unfortunately, T-mobile was abandonned for a few years, while waiting to
be absorbed into AT&T, and AT&T didn't want t-mobile to fix areas where
AT&T had existing coverage.

Once the merger was killed, then t-mobile had no choice but to fend for
its survival and start investing to fix its network instead to of
preparing to shutdown every area where AT&T was already covering.

So yes, T-mobile has improved significantly since the merger was killed,
but those years of abandonment are still felt because it hasn't caught
up fully yet.

As a note of comparison:

in 1998/1999, at a motel in upstate NY, I had Omnipoint coverage on a
Nokia 1900-only phone.

In 2010, I had none. Nothing. Nada. (T-Mobile bought Voicestream which
had bought Omnipoint). I reckon T-Mo had shutdown that antenna because
AT&T was already covering the area.

Unfortunately, AT&T SIMs disable the ability to manually check for
available networks on iphone, so with an AT&T SIM I can't check if
T-Mobile has regained coverage there.

 

[Stijn De Jong]

On Fri, 17 Feb 2017 21:06:50 -0500, nospam wrote:

vast areas of california have no att, sprint or verizon coverage.

no carrier covers *everywhere*.

if where *you* go lacks t-mobile, then get another carrier. for others,
t-mobile works just fine, even in out of the way areas.

For once, nospam and I agree in principle and in practice.

 

[Stijn De Jong]

On Fri, 17 Feb 2017 18:00:11 -0800, sms wrote:

Those maps don't really show the coverage holes, nor are they
up-to-date. I.e. Verizon just put in a tower right next to Cupertino
City Hall (a fake tree) that has improved coverage.

I completly understand that the data I showed (which implied that the
coverage was about the same) could be bad data.

But you have to realize I've heard a lot of bs on the net where people who
have one brand think it's better than the other two brands (of anything),
even though they, themselves, have never even tested brand B or C. (It just
happened on the digital photo group, for example, where people said
"preview" was better at X than Paint.NET and then we find out that all
those people who said that had NEVER even used Paint.NET once in their
entire lives).

My point is that anyone who claims that cellular data sucks for one carrier
than the other generally has lousy data points since almost nobody (not
even me) carries three similar phones with them everywhere they go.

So if the OpenSignal coverage maps suck, the question simply becomes where
can we get good trustworthy coverage data for any particular USA area?

But the issue is not in urban and suburban areas, it's outside of those
areas. Vast areas of California with no T-Mobile coverage at all, and a
lot of those places are places that we like to go.

This may or may not be true.
My experience is with Verizon, AT&T, and T-Mobile, but while I have had all
three (and while I find them about the same in coverage where I live), I
had them sequentially, so the only real comparison was the last day with
the prior carrier and the first day with the next (which isn't all that
scientific).

What we really need is a *reliable* trustworthy coverage map.
Does that exist?

Where can we find it?

 

[nospam]

In article <58a7672f$0$9555$b1db1813$e2fc9064@news.astraweb.com>, JF
Mezei <jfmezei.spamnot@vaxination.ca> wrote:

t-mobile's coverage is steadily getting *better*, not worse.

Unfortunately, T-mobile was abandonned for a few years, while waiting to
be absorbed into AT&T, and AT&T didn't want t-mobile to fix areas where
AT&T had existing coverage.

there was no abandonment.

Once the merger was killed, then t-mobile had no choice but to fend for
its survival and start investing to fix its network instead to of
preparing to shutdown every area where AT&T was already covering.

that's a bit of revisionist history.

t-mobile got a chunk of cash as a result of the merger not going
through, which they used to expand their network.

they also refarmed their network so that aws is not required anymore.

 

[The Real Bev]

On 02/16/2017 07:21 PM, Jeff Liebermann wrote:

On Thu, 16 Feb 2017 19:06:07 -0800, The Real Bev
bashley101@gmail.com> wrote:

I really want to know WHERE the cell towers are. T-Mobile has piss-poor
coverage in out-of-the-way places and rather than driving around in
circles I'd like to at least head toward a tower. Will this do what I want?

I've been thinking of building (and selling) such a device. It can be
done if:
1. You have an RF direction finder.
2. You know the sub-band where to expect the vendors transmissions.
3. You know the SID (system ID) of the vendor.
4. You have a map or database of the vendors service areas.

I used to design direction finders, so I have more than an average
clue as to how this MIGHT be done. I'm not up to speed on cellular,
but I think I can catch up. Basically, an SDR receiver that scans,
looks for a signal direction, identifies it by RF sub-band and service
area, draws a line on a map, and records the line. Drive around a
little and soon you'll have many lines that cross at one point, which
is the cell site. You won't get any ID numbers, but you can get those
from any phone that can display the field service mode.

Marketing research: How much would pay for such a device?

Nothing. I've been hooked on 'free' for a long time, especially since
the paid version is rarely significantly better than the free version.

Exception: EBookDroid. The guy is in Russia and can't take PayPal
directly. We bought the paid version and even wanted to send him some
money, but we can't.

He responds to email and fixes stuff if it needs fixing or improving.
Just what hubby used to do when he was selling software.

--
Cheers, Bev
"If you watch TV news, you know less about the world than
if you just drank gin straight from the bottle."
- Garrison Keillor

 

[JF Mezei]

On 2017-02-17 17:21, nospam wrote:

that's a bit of revisionist history.

t-mobile got a chunk of cash as a result of the merger not going
through, which they used to expand their network.

Prior to the merger being blocked, T-Mo had throun in the towel. T-Mobil
(DE) had signaled it wanted out of US business amd T-Mo (USA) had
stopped investing since it knew its customers would fall onto AT&T's network

Once deal was killed by FCC, T-MO did get cash and spectrum, and that
allowed it to bring itself back to life. But it does not negate the fact
that they had thrown in the towel before, hoping to be bought by AT&T.


> they also refarmed their network so that aws is not required anymore.

The refarming should have been done way before. But wasn't because T-Mo
was expeciting to shutdown its network and move its customers over to
AT&T, at which point, the iPhone would work.

At time of abandonment, T-Mo had 2G on 1900 and 3g on 1700 (aws). No
LTE. Once it got the jolt to bring it back to life, the refarming
allowed it to put 3G on 1900 and LTE on 1700.

The big guys lobbied to limit 1700 to LTE. That left T-Mobile as an
orphan trying to put 3G on 1700, limiting equipmnent and handset
support. (hence no iPhone for so long).

Once FCC killed AT&T purchase of T-Mo, the iPhone magically became
available for 3G on 1700 (benefiting canadian new entrants who only have
1700) and the influx of spectrum allowed T0Mo to start shifting 3G from
1700 to 1900 so it could start to deploy LTE on 1700.

But the only reason it didn't do that before was that it was expecting
to shutdown its network so there was no point spending money to refarm
your spectrum if it will be shutdown not long after AT&T signs the deal
on dotted line.

 

[nospam]

In article <58a7834e$0$61762$c3e8da3$e074e489@news.astraweb.com>, JF
Mezei <jfmezei.spamnot@vaxination.ca> wrote:

that's a bit of revisionist history.

t-mobile got a chunk of cash as a result of the merger not going
through, which they used to expand their network.

Prior to the merger being blocked, T-Mo had throun in the towel. T-Mobil
(DE) had signaled it wanted out of US business amd T-Mo (USA) had
stopped investing since it knew its customers would fall onto AT&T's network

no towel was thrown.

Once deal was killed by FCC, T-MO did get cash and spectrum, and that
allowed it to bring itself back to life. But it does not negate the fact
that they had thrown in the towel before, hoping to be bought by AT&T.

it did get a boost from the cash and spectrum but it was hardly dead.

they also refarmed their network so that aws is not required anymore.

The refarming should have been done way before. But wasn't because T-Mo
was expeciting to shutdown its network and move its customers over to
AT&T, at which point, the iPhone would work.

nope.

At time of abandonment, T-Mo had 2G on 1900 and 3g on 1700 (aws). No
LTE.

there was no abandonment.

Once it got the jolt to bring it back to life, the refarming
allowed it to put 3G on 1900 and LTE on 1700.

nope on that too.

t-mobile uses lte bands 2, 4 & 12, which are 1900, 1700 & 700 mhz,
respectively.

note that at&t and verizon also use band 4, the band that's at 1700 mhz.

The big guys lobbied to limit 1700 to LTE. That left T-Mobile as an
orphan trying to put 3G on 1700, limiting equipmnent and handset
support. (hence no iPhone for so long).

nope. t-mobile got aws because it was cheaper.

Once FCC killed AT&T purchase of T-Mo, the iPhone magically became
available for 3G on 1700 (benefiting canadian new entrants who only have
1700) and the influx of spectrum allowed T0Mo to start shifting 3G from
1700 to 1900 so it could start to deploy LTE on 1700.

nope.

But the only reason it didn't do that before was that it was expecting
to shutdown its network so there was no point spending money to refarm
your spectrum if it will be shutdown not long after AT&T signs the deal
on dotted line.

nope. there was no planned shutdown.

 

[The Real Bev]

On 02/17/2017 08:45 AM, Stijn De Jong wrote:

Moving to T-Mobile, I loved that they did everything differently. I mean
everything. I could buy my own phone. No contract. No data overage charges
ever. Calling Europe was 20 cents a minute. Data is unlimited in Europe. No
roaming charges. And, I didn't have to have data if I didn't want it. I
could get phones from them for an additional $50 over what I could get on
the market, where they'd charge me 1/24th the phone on the bill. I didn't
even have to tell them what phone I was using. Everything about T-Mobile
was different than Verizon & AT&T.

I've used T-Mobile for years just because of their (now defunct, but
grandfathered in for us previous customers) $10/year
unused-minutes-rollover plan. Coverage is limited to interstates and
big cities, but I can live with that. My Verizon friend gets coverage
on the ski slope, but I have to drive to 2 miles away in town before I
can get signal. Minimal, but the incremental jump to a better plan is
far bigger than I'm willing to make.



--
Cheers, Bev
"It is never fallacious to properly cite Donald Knuth in
lieu of providing your own argument." --Sun Tzu

 

[nospam]

In article <o8816k$3nj$1@dont-email.me>, The Real Bev
<bashley101@gmail.com> wrote:

I've used T-Mobile for years just because of their (now defunct, but
grandfathered in for us previous customers) $10/year
unused-minutes-rollover plan. Coverage is limited to interstates and
big cities, but I can live with that.

t-mobile coverage, even on that plan, is *much* more than just
'interstates and big cities'.

My Verizon friend gets coverage
on the ski slope, but I have to drive to 2 miles away in town before I
can get signal.

then why keep it at all?

Minimal, but the incremental jump to a better plan is
far bigger than I'm willing to make.

only because you haven't researched what options exist.

 

[Jeff Liebermann]

On Fri, 17 Feb 2017 14:27:15 -0800, The Real Bev
<bashley101@gmail.com> wrote:

On 02/16/2017 07:21 PM, Jeff Liebermann wrote:
Marketing research: How much would pay for such a device?

Nothing. I've been hooked on 'free' for a long time, especially since
the paid version is rarely significantly better than the free version.

Oh well. It's rather difficult to build a company based on a free
product (unless one sells advertising). Once the DF method is
established by me or someone else, I'm sure it will be cloned, copied,
or distributed as "open hardware". That's why I haven't done anything
with the idea for several decades. Enjoy free while it lasts. I'm
thinking more of a Kickstarter, Indiegogo, or other crowdfunding
project.

--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

 

[sms]

On 2/17/2017 3:34 PM, The Real Bev wrote:

<snip>

I've used T-Mobile for years just because of their (now defunct, but
grandfathered in for us previous customers) $10/year
unused-minutes-rollover plan.

I have one T-Mobile phone with that plan still. I hate to let it go
because it's only $10 per year.

Coverage is limited to interstates and
big cities, but I can live with that. My Verizon friend gets coverage
on the ski slope, but I have to drive to 2 miles away in town before I
can get signal. Minimal, but the incremental jump to a better plan is
far bigger than I'm willing to make.

I recall driving to Yosemite in the winter one year. It was snowing. We
arrived at the place we were staying and they hadn't left the key out
for us. I called the caretaker who brought over the key. No big deal.
But in this area there is only Verizon coverage (native Sprint customers
can roam though). There is no AT&T coverage and no T-Mobile coverage. A
pay phone was probably a 30 minute drive away. This was not out in the
middle of nowhere, it was in a residential development just off one of
the main park roads.

Glad I had a phone that worked on Verizon's network. Even though there
apparently is some spotty AT&T coverage nearby, it would not be
practical to drive around searching for it. See the map at
<http://oi66.tinypic.com/nywmrn.jpg>.

Now, even though I am on an AT&T MVNO, with roaming, I take along a
Verizon network phone on trips. It's worth the $30 per year to keep it
active. I have found several areas in Oregon and California, that are
not terribly remote, where only Verizon works.

Speaking of ski slopes, my wife once foolishly decided that she was
going to ski some moguls at Homewood Ski Area. She injured herself. She
was able to call me to call the ski patrol to come fetch her. On other
carriers, i would not have been possible for her to call me, but on
Verizon it was. That might have saved her life. So remember, if life is
valuable, use Verizon.

 

[sms]

On 2/17/2017 1:12 PM, JF Mezei wrote:

On 2017-02-17 14:44, nospam wrote:

t-mobile's coverage is steadily getting *better*, not worse.

Unfortunately, T-mobile was abandonned for a few years, while waiting to
be absorbed into AT&T, and AT&T didn't want t-mobile to fix areas where
AT&T had existing coverage.

Once the merger was killed, then t-mobile had no choice but to fend for
its survival and start investing to fix its network instead to of
preparing to shutdown every area where AT&T was already covering.

So yes, T-mobile has improved significantly since the merger was killed,
but those years of abandonment are still felt because it hasn't caught
up fully yet.

In the west, there were roaming agreements that T-Mobile had with AT&T
that expired and were not renewed. So coverage that had been available
to T-Mobile customers disappeared. T-Mobile has improved coverage in
urban areas, but they have little interest in building expensive
infrastructure in lightly populated areas, and AT&T demands exorbitant
amounts for roaming and it's not clear what the outcome was of the FCC
ruling
<https://arstechnica.com/business/2014/12/t-mobile-wins-fight-against-att-and-verizon-over-data-roaming-charges/>.
If it's a rural carrier other than AT&T then there is often T-Mobile
roaming.

For users that never travel outside of urban areas T-Mobile is usable,
but if you like to travel to, or through, rural areas, it's not a good
choice.

 

[Jeff Liebermann]

On Fri, 17 Feb 2017 12:02:54 +0100, Mikko OH2HVJ
<mikko.syrjalahti@nospam.fi> wrote:

Jeff Liebermann <jeffl@cruzio.com> writes:

I've been thinking of building (and selling) such a device. It can be
done if:
1. You have an RF direction finder.
2. You know the sub-band where to expect the vendors transmissions.
3. You know the SID (system ID) of the vendor.
4. You have a map or database of the vendors service areas.

You could also add some LTE/UMTS module, some of these can do a network
scan with an AT-command and give you the cell id, technology, channel
number etc. of all 'visible' base station.

Apparently even some USB dongles can do this, so you could connect some
cheap SDR+modem+GPS to an RPi and do your magic.

Thanks. To be uncharacteristically honest, I haven't really thought
about the cellular data extraction and collection aspects. I do RF,
not programming. If this becomes a real project, I'll probably do the
system design, DF antenna, and RF, while someone else is either hired
or invested as the programmist.

I did some light weight Googling and found:
<http://www.rtl-sdr.com/tag/cell-phone/>
<http://www.rtl-sdr.com/rtl-sdr-cell-phone-imsi-tmsi-key-sniffer/>
<http://www.rtl-sdr.com/analyzing-td-lte-rtl-sdr/>

>There are also cell tower location databases like Opencellid.

<https://en.wikipedia.org/wiki/OpenCellID>
Yep. That will certainly be useful. Mostly, what I want is to find a
new cell site with the direction finder, and then determine which
services and vendors are on the tower, building, pole, whatever. A
tower ID to lat-long database will certainly be useful, but the real
problem is what frequency to use. For example, for LTE:
<https://en.wikipedia.org/wiki/List_of_LTE_networks>
the bands in use world wide are many and varied. Same with TDM vs
FDM, full duplex vs half duplex, odd splits. Then, there are
sub-bands for each vendor. Notice the number of question marks in
above tables.



--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

 

[Jeff Liebermann]

On Fri, 17 Feb 2017 20:16:06 +0100, "Carlos E. R."
<robin_listas@invalid.es> wrote:

On 2017-02-17 19:53, JF Mezei wrote:
Cell antennas are very directional.

I know. We installed them at a small company I worked with.
But the antenna on the mobile phone is not. The mobile can not know the
direction of the signal from the signal alone, that's what I said.

Not exactly. The handset has to pass an SAR (specific absorption
rate) test in order to convince the FCC that the handset is not going
to fry the users brain with too much RF. To make that work, handset
antennas are usually located on the side away from the users head, at
the bottom of the phone, or backed by a metal shield. On simulations
and in an RF anechoic chamber, the antenna pattern is somewhat
directional favoring the directions away from the users head.

"Mobile Phone in Vicinity of Human Head - SAR calculation"
<http://www.wipl-d.com/applications.php?cont=emc/sar-calculation>
See Fig 8:

As for the tower antenna patterns being direction, it's a matter of
what you consider directional. In the typical 3 sided tower
configuration, the sector antennas have a horizontal beamwidth of
about 60 degrees. The tower can and does indicate which sector is
being used, but that has a granularity of 120 degrees, which is hardly
accurate enough to determine anyones position. On systems that use
various forms of AGPS (augmented GPS) using TDOA (time difference of
arrival), two different towers can obtain a location fix of a handset.
That requires double the number of available receivers, two towers
that can hear the handset, and the necessary technology. That's why
I've only seen it on demonstration projects. It's also useless for
locating the tower, which I believe was the topic of discussion prior
to this topic drift.

The vertical beamwidth of sector antennas is very sharp. The vertical
beamwidth and downtilt angle are the major contributors to what
determines the coverage area of a cell site. Too narrow, and signal
will go over the heads of users close to the tower. Too wide, and the
tower will be talking to gophers and airplanes, not users on the
ground. For example, a common Andrew HBXX-6517DS-VTM antenna:
http://www.commscope.com/catalog/wireless/product_details.aspx?id=15654
has a horizontal beamwidth of 66 degrees, and a vertical beamwidth of
4.7 degrees. Draw a 5 degree angle on a piece of paper and you'll see
the problem. It's bad enough that there are products to vertically
align sector antennas to about +/-0.1 degrees.
<https://sunsight.com>
<https://sunsight.com/index.php/products/95-sunsight-instruments/products/199-antenna-alignment-tool>
However, that's also useless for locating handsets, unless you want
the altitude.

Dinner... gotta run.
--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

 

[Jeff Liebermann]

On Sat, 18 Feb 2017 01:37:03 -0000 (UTC), Lewis
<g.kreme@gmail.com.dontsendmecopies> wrote:

In message <nkoind-hkg.ln1@minas-tirith.valinor> Carlos E. R. <robin_listas@invalid.es> wrote:
There is no way the phone can determine the location of the tower from
the signal,

Sure they can. The signal include Latitude and Longitude for the tower.

My GSM phones show a valid lat-long. My CDMA phones show no data.
This is with multiple phones on AT&T (GSM), T-Mobile (GSM), Verizon
(CDMA) and Sprint (CDMA) in the Monterey Bay area of California. Your
experience may be different in other parts of the country or with
other system operators.

Finding CDMA towers has been somewhat of a challenge. I tried to map
local sites in the late 1990's and gave up in about 2003 (for medical
reasons):
<http://802.11junk.com/cellular/>
Yeah, I know it's old, awful, ugly, incomplete, and inaccurate, but it
was acceptable for something built 15 years ago using just a text
editor.



--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

 

[nospam]

In article <tjcfacpudfdh1vf3slsh84c254ghif55mb@4ax.com>, Jeff
Liebermann <jeffl@cruzio.com> wrote:

There is no way the phone can determine the location of the tower from
the signal,

Sure they can. The signal include Latitude and Longitude for the tower.

My GSM phones show a valid lat-long. My CDMA phones show no data.
This is with multiple phones on AT&T (GSM), T-Mobile (GSM), Verizon
(CDMA) and Sprint (CDMA) in the Monterey Bay area of California. Your
experience may be different in other parts of the country or with
other system operators.

sprint towers include lat/long everywhere i've tried. not all phones
will show it, however.

 

[Carlos E. R.]

On 2017-02-18 02:37, Lewis wrote:

In message <nkoind-hkg.ln1@minas-tirith.valinor> Carlos E. R. <robin_listas@invalid.es> wrote:
On 2017-02-16 21:57, Stijn De Jong wrote:
The one potentially nice thing that OpenSignal provided on Android was a
compass-like pointer toward the tower it's connected to; however, that
pointer doesn't seem even remotely aligned with where I know that tower to
be, so, I'm not sure if that compass-like pointer is fluff or if there is a
major reflection of radio waves going on off of someone's solar panel array
or expansive windows overlooking the valley below.

There is no way the phone can determine the location of the tower from
the signal,

Sure they can. The signal include Latitude and Longitude for the tower.

That's not the signal.

That's decoding the data on it, and reading it. Then finding via GPS the
exact location of the terminal, then calculating the direction of the tower.

--
Cheers,
Carlos E.R.

 

[nospam]

In article <o88ahl$99g$2@gioia.aioe.org>, Stijn De Jong
<stijndekonlng@nlnet.nl> wrote:

OMG. No way. Verizon is far superior in Silicon Valley and the Bay Area.

they're all about the same.

I've had all three, although not concurrently.
I go camping a lot, and skiing, where I'm with a bunch of guys, all of whom
are on the various carriers.

Over the years, it's been getting better and better on all the carriers,
but sometimes Verizon is the lousy one, sometimes AT&T, and sometimes
T-Mobile.

you left out sprint.

As nospam said, they're all about the same.
And I've had Verizon, AT&T, and T-Mobile (in that order) in the same
location.

However, the only true test would be to have all three similar phones in
your hands at the same time for the tests, which nobody is gonna do.

some do.

So everyone is just guessing with bad data (sort of like how climate change
debates go).

mostly.

 

[tlvp]

On Fri, 17 Feb 2017 00:58:44 +0000 (UTC), Stijn De Jong wrote:

I don't know if a phone can connect to two towers at once
though.

Can it?

A dual SIM phone, with both SIMs active, and using different carriers, not
only *can*, it *must* . 'Zat help? Cheers, -- tlvp
--
Avant de repondre, jeter la poubelle, SVP.

 

[Savageduck]

On 2017-02-18 00:03:15 +0000, sms <scharf.steven@geemail.com> said:

On 2/17/2017 3:34 PM, The Real Bev wrote:

snip

I've used T-Mobile for years just because of their (now defunct, but
grandfathered in for us previous customers) $10/year
unused-minutes-rollover plan.

I have one T-Mobile phone with that plan still. I hate to let it go
because it's only $10 per year.

Coverage is limited to interstates and
big cities, but I can live with that. My Verizon friend gets coverage
on the ski slope, but I have to drive to 2 miles away in town before I
can get signal. Minimal, but the incremental jump to a better plan is
far bigger than I'm willing to make.

I recall driving to Yosemite in the winter one year. It was snowing. We
arrived at the place we were staying and they hadn't left the key out
for us. I called the caretaker who brought over the key.

Was this at Fish Camp, and I guess at some place other than Tenaya
Lodge or the Narrow Gauge Inn?

No big deal. But in this area there is only Verizon coverage (native
Sprint customers can roam though). There is no AT&T coverage and no
T-Mobile coverage. A pay phone was probably a 30 minute drive away.
This was not out in the middle of nowhere, it was in a residential
development just off one of the main park roads.

Usually if I take the Southern route (41) to Yosemite I will spend one
night at either Tenaya Lodge or the Narrow Gauge Inn, both technically
in Fish Camp on hwy 41. I get good Verizon coverage there and both have
free in-house WiFi. In Yosemite, depending on my actual plan and time
of the year I spend one or two nights at the Yosemite Valley Lodge,
which also has free in-house WiFi and Verizon coverage.

Glad I had a phone that worked on Verizon's network. Even though there
apparently is some spotty AT&T coverage nearby, it would not be
practical to drive around searching for it. See the map at
http://oi66.tinypic.com/nywmrn.jpg>.

Now, even though I am on an AT&T MVNO, with roaming, I take along a
Verizon network phone on trips. It's worth the $30 per year to keep it
active. I have found several areas in Oregon and California, that are
not terribly remote, where only Verizon works.

Speaking of ski slopes, my wife once foolishly decided that she was
going to ski some moguls at Homewood Ski Area. She injured herself. She
was able to call me to call the ski patrol to come fetch her. On other
carriers, i would not have been possible for her to call me, but on
Verizon it was. That might have saved her life. So remember, if life is
valuable, use Verizon.

--
Regards,

Savageduck