If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below. |
|
|
Thread Tools | Display Modes |
#41
|
|||
|
|||
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) |
#42
|
|||
|
|||
Carrying Skis in a Single...
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? |
#43
|
|||
|
|||
Carrying Skis in a Single...
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 |
#44
|
|||
|
|||
Carrying Skis in a Single...
wrote)
OK, that's enough "cellular 101". If you want more, read my book. Link? Link? Montblack |
#45
|
|||
|
|||
Carrying Skis in a Single...
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. |
#46
|
|||
|
|||
Carrying Skis in a Single...
|
#47
|
|||
|
|||
Carrying Skis in a Single...
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? |
#48
|
|||
|
|||
Carrying Skis in a Single...
(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. |
#49
|
|||
|
|||
Carrying Skis in a Single...
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). |
#50
|
|||
|
|||
Carrying Skis in a Single...
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. |
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
Carrying Skis in a Single... | EridanMan | Piloting | 36 | May 12th 06 05:06 AM |
Mazda single rotor weight? | [email protected] | Home Built | 6 | January 10th 06 06:44 PM |
O2 single pilot and VLJ | [email protected] | Piloting | 5 | August 18th 05 09:15 AM |
Is taking off on single mag bad for engine | flyer | Home Built | 10 | September 21st 03 09:43 PM |
WANTED: partnership, rental or club with fast single or light twin in San Diego | Jim McGarvie | Aviation Marketplace | 0 | September 13th 03 03:55 PM |