Carrying Skis in a Single...

On 12-May-2006, "EridanMan" wrote:

Dual band phones are an absolute must if you want to get service
outside of any major metro area, just understand that in analog mode,
the phone will run out of juice VERY quickly, and in the western
wilderness, your chance of getting a signal is still relatively low...
So make sure not to leave the phone on for very long


The above is possibly misleading. In analog mode a cellphone will draw much
more power only in standby (idle) mode. In conversation mode (i.e. while
engaged in a call) the battery drain is about the same as in digital mode.
Since in the situation under discussion you would be using the cellphone to
call for help, there is no reason to leave it on when not in use



All nextel Iden Phones made in the past four years (starting with the
i88s and i730) have built in SiRF GPS chips that are capable of making
a stand-alone GPS fix... Something to remember if you or your
passengers happen to have one on you (and no other GPS equipment).
Granted, you'll still need some form of communication to transmit that
fix... but it is an option for _getting_ a fix


And virtually all CDMA phones have built-in "assisted GPS" technology that
allows the network to provide accurate location to the local 911 call
handling facility. That said, it's a good idea to be able to report your
position as accurately as possible.


-Elliott Drucker (MSEE, involved in wireless technology development for 27
years)

wrote in message
news:dO89g.2155$UY6.1537@trnddc08...

On 12-May-2006, "EridanMan" wrote:

Dual band phones are an absolute must if you want to get service
outside of any major metro area, just understand that in analog mode,
the phone will run out of juice VERY quickly, and in the western
wilderness, your chance of getting a signal is still relatively low...
So make sure not to leave the phone on for very long


The above is possibly misleading. In analog mode a cellphone will draw
much
more power only in standby (idle) mode. In conversation mode (i.e. while
engaged in a call) the battery drain is about the same as in digital mode.

Hmmm...I was told just the opposite (that analog uses more at idle and MUCH
more during the call). IIRC, an analog system has to transmit and receive
_constantly_, whereas a digital signal _pulses_. Correct?

On 12-May-2006, "Matt Barrow" wrote:

Hmmm...I was told just the opposite (that analog uses more at idle and
MUCH more during the call). IIRC, an analog system has to transmit and
receive
_constantly_, whereas a digital signal _pulses_. Correct?


You were misinformed. The factors that determine "talk time" are complex,
but in the case of digital mode much of the power expended goes into digital
processing of the received signal rather than out the antenna as transmitted
RF energy. That's why the phone gets warm after you've been talking for a
while.

Digital phones conserve power in idle mode by only turning on for a tiny
fraction of the time to receive their specific paging "slot" during which,
if they have an incoming call, the base station will signal them. Analog
phones require far less power to receive in idle mode, but must receive
continuously because the paging channel is not "slotted" like the ones used
for digital. Actually, there is a "standard" for a slotted paging channel
for analog that would extend standby time by a factor of about 10X, but it
has never been implemented.

Analog and CDMA cellphones transmit continuously in conversation mode, with
power varying depending upon path loss to the serving base station. GSM and
iDEN phones do indeed "pulse" -- transmitting 1/8 or 1/3 (or 1/6) of the
time, respectively, but with much, much higher peak power.

OK, that's enough "cellular 101". If you want more, read my book.

-Elliott Drucker

wrote)
OK, that's enough "cellular 101". If you want more, read my book.


Link? Link?


Montblack

Newps wrote:


EridanMan wrote:

Dual band phones are an absolute must if you want to get service
outside of any major metro area,


Bull****. We don't allow metro areas in this state and I have to get
between mountain ranges to lose digital coverage.

Dual band != Analog. Most of the US cellular stuff is split between
the 800 (old analog band, but largely carrying digital traffic) and
1900 MHz. The problem is that there are some 1900MHz only phones
and these won't work well in areas without 1900 MHz service (T-Mobile
is the primary purveyor of these).

Mine's a quad. Never use the additional bands here, but Australia
was 900MHz (and oddly there wasn't any place big enough for a
public airstrip that we didn't have GSM and GPRS (data) service
while we were there. The aussies are way ahead of us on coverage.

wrote:


And virtually all CDMA phones have built-in "assisted GPS" technology that
allows the network to provide accurate location to the local 911 call
handling facility. That said, it's a good idea to be able to report your
position as accurately as possible.


Other than the misuse of the word virtually, all newer cellphones are
going to have some precise location feature by law. It can either be
by GPS or some sort of interferometry work by the base stations. I
like the latter.

wrote in message
newsfV8g.18553$Lh.1985@trnddc01...

As to the issue of carrying skis, there are a very few models that had ski
tube factory options. One that comes to mind is the Bellanca Viking.
There
are probably STCs for some of the more popular models. The good news is
that the new "shaped" skis tend to be quite a bit shorter that the old
"straight" skis.


-Elliott Drucker

Didn't the early Diamond DA40s have a ski tube that went behind the back
seats?

(as an aside, I carry a Globalstar satellite phone when I fly.)

Locating cellphones (various people wrote):
: All nextel Iden Phones made in the past four years (starting with the
: i88s and i730) have built in SiRF GPS chips that are capable of making
: a stand-alone GPS fix... Something to remember if you or your
: passengers happen to have one on you (and no other GPS equipment).
: Granted, you'll still need some form of communication to transmit that
: fix... but it is an option for _getting_ a fix

: And virtually all CDMA phones have built-in "assisted GPS" technology that
: allows the network to provide accurate location to the local 911 call
: handling facility. That said, it's a good idea to be able to report your
: position as accurately as possible.

You can always call the provider, give the phone's ESN, and ask which cell
it is registered with (or was last registered with). You don't have to
be actively making calls for the phone to register, as the registration is
what allows calls made to you to follow you around. I have a huge number
of telemetry devices equipped with CDMA modems that are used by the
electric utility industry. We can, through Verizon, find out which
cell each one is on, when it last transmitted data, what IP it is/was
using, etc. These devices are scattered in places that don't have real
good CDMA coverage, and still work great with data.
This is because the RSSI required to use digital services such as text
messaging is much lower than that required to place calls. This means
that you might be able to get off a text message where you can't get
a call through because of low signal.

Also also note that antenna height is critical with line-of-sight radio
technology (like microwave cellphones). If you can climb a ridge you
will get a much better chance of "seeing" a tower.
--
Aaron C.

Elliotte -

Yes I was over-simplifying, your explanation is more precise.

The primary point I was trying to convey was that-

A- In general, in a low coverage area, you stand a better chance of
getting a signal out with analog

but

B- be careful with analog and don't leave the phone on for hours and
hours in standby like you do with digital, because pretty soon you'll
have no phone at all:-P.

I've been out of the E911 stuff now for ~2 years. You'll have to
forgive my Iden Bias, I worked on the SiRF integration to the Iden
platform (J2ME side). I know E911 Mandates that all carriers be
Location capable, but as you said- most phones have 'Assisted GPS',
meaning that unless the phone must access an ephemers database (and a
precise time-stamp) from the data network, making the GPS worthless if
you have no data network.

I am also unsure how many brands of handset (other than the Iden Line)
allow access to the position system through the phones default
ergonomics (Not require a special j2me App or test mode).

Two different definitions of Dual-Band.

Dual-Band in the CDMA world _generally_ refers to digital and analog
support

You know, I've been out of handsets long enough, its possible Sprint
doesn't even sell the old digital/analog dual band phones any more.

(Dual|tri|quad)-Band in the GSM world is what you describe.