Re: APRS-IS client - quick questions
- Thanks Lynn - once again showing that Hams are genius material.
On 10/16/09, Lynn W. Deffenbaugh <KJ4ERJ@...> wrote:
> Kevin Jensen wrote:
>> I know you are busy. My background is electrical engineering so I am
>> very curious about the application. Yes I will read more about it in
>> the groups.yahoo page; but am at work where I do not have access. So
>> hope you do not mind a couple questions.
> If you don't mind random delays in getting answers, I certainly don't
> mind answering them! I hope you don't mind that I copied the answer to
> the group so that others might benefit.
>> 1) My cellphone will go into battery save mode after a minute. Will
>> the APRS-IS client still keep sending beacon points? When I look on
>> the APRS GOOGLE map of my activity (I am N1KCG-12) it looks like it
>> stopped after I got on the highway, after about two or three minutes.
> In my experience, when the phone turns "off" in battery save mode, the
> GPS is also turned off. My application doesn't muck at all with power
> settings, so beaconing will stop, but incoming APRS-IS updates will
>> 2) How rapidly will my battery get drained running APRS-IS? Any data
>> on its effect on power in a typical cellphone with a GPRS circuit, and
>> data connectivity?
> The battery with GPS and APRS-IS active will drain quite quickly. I
> always plug my phone into a power adapter in the car and only turn off
> the power savings timer when I KNOW I want to continue tracking. Once
> in power saver with only a modest-radius APRS-IS feed active, it'll last
> longer, but still MUCH less than if the client itself were closed or
> APRS-IS disabled.
> The client also transmits battery level telemetry. You can see mine at:
> The week view has some good days in it and the month or year view shows
> just how mean I've been to my battery. I'm now running an extended
> capacity battery on my AT&T Tilt. I'm happy with the battery life (3-4
> hours with full APRS-IS and GPS, 6 hours with only APRS-IS), but I don't
> like the fact that it no longer fits in my belt clip.
>> 3) I assume that the APRS-IS client needs a GPS circuit in the
>> cellphone, and a unlimited data connection. Is that true?
> Yes, the client relies on a GPSapi-supported GPS unit and sends/receives
> lots of data so an unlimited plan is highly recommended.
>> 4) Since I am running WM6 on my cellphone, will the APRS-IS client
>> run in the background, while I use the phone for other activities?
>> Can I receive phone calls? Supposing it depends on the cellphone, but
>> that most that can run the APRS-IS client under WM6 might be able to
>> handle the multitasking.
> The application will continue to run in the background, but the ability
> to maintain a data connection while receiving calls is up to the
> cellular provider and the infrastructure around you. I've had calls go
> straight to voice-mail in some cells. I've had the data connection stop
> when the phone rang and resume when I terminated the voice call. And
> I've had the data connection continue operating while talking on the
> phone. And these were all on the SAME phone, just in different
> geographical areas.
> Lynn (D) - KJ4ERJ - Author of APRSISCE for Windows Mobile