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<DocScrutinizer>
another reason why you should ignore tech specs originated in USA, and better do your own technically based specs for anything you want to build
<DocScrutinizer>
if you don't get it what I'm talking about, look at GSM vs the mess they got over in USA with mobile phone bands
<DocScrutinizer>
and they managed to mess it up despite GSM got invented and defined over here in Germany, in a proper decent way
<DocScrutinizer>
now figure where you end with anything invented and specified in USA
<DocScrutinizer>
or simply read that pdf to get an idea
<chrisb>
DocScrutinizer: my, my let's not generalize.
<chrisb>
DocScrutinizer: there is a business case as well as a technical case here
<DocScrutinizer>
sure
<chrisb>
DocScrutinizer: are you familiar with LightSquared and its financial backer?
<DocScrutinizer>
but the business case is always more important than the technical one, when the story starts in USA
<DocScrutinizer>
and no, I never heard of lightsquare before I read that paper some 30min ago
<DocScrutinizer>
but I'm familiar with quite some of the technical headache that got quoted in that paper
<DocScrutinizer>
regarding GPS performance
<DocScrutinizer>
as well as general mindset in industry regarding how to implement sth like a RF rx filter
<DocScrutinizer>
you usually simply copy the reference design
<DocScrutinizer>
not validate the technical fundamentals that it's based on, like sidebands that need to either be included or better cut off by such a filter
<DocScrutinizer>
and I know the quality of reference designs originating in USA vs those e.g. done in Germany
<DocScrutinizer>
and the totally differnet mindset that speaks to me from those schematics
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<chrisb>
the US has lots of experience with the difference between bands for signalling position and bands for two way communication
<chrisb>
LightSquared is trying to *innovate* on some unused bandwidth it managed to uncover
<chrisb>
they probably have to pump alot of power into a small band, 50MHz, and it bleeds or rings out into well used bands for positioning
<chrisb>
i hope LightSquared can succeed, but not at the expense of lots of GPS receivers now in service
<chrisb>
i'm sure very few of these are built in the US
<chrisb>
it seems to me like a typical issue of innovation in the US
<chrisb>
it is a similar business case to voice-over-IP and video-over-landline
<chrisb>
cable TV and telco fight
<chrisb>
but innovation mostly wins
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<qi-bot>
Jon Phillips: @robmyers that is great you have a @milkymistvj @qihardware. We need more great owners like you to make it better! Free service for buyers! ( 176140596107427841@rejon - 17s ago via web )
<kristianpaul>
lol,
<kristianpaul>
(“I’m not listening! I can’t
<kristianpaul>
hear you!”)
<kristianpaul>
oh god.. this old school way to work, is a shame..
<kristianpaul>
lol, politicians may be doing more noise that the one that the poor filter desing let pass
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<DocScrutinizer>
well, actually I think lightsquared is a bit... squared to consider using Watts-of-TX BTS in a spectrum next to GPS
<DocScrutinizer>
the original culprit of all this mess of course is FCC, what else ;-P
<DocScrutinizer>
for WLAN you have a clear definition of the allowable TX power for each channel, incl crosstalk to adjacent freq. If FCC had considered equally precise specs for GPS band, L^2 never would've thought of such idiotic thing like implementing a terrestrial network some 25MHz next to GPS signals
<DocScrutinizer>
or - depending on that FCC better specs - GPS manufacturers from beginning would've considered using proper filters to get the needed crosstalk resilience into their designs
<DocScrutinizer>
but since, according to FCC general policy, everybody can build crap as long as it simply fails passively and doesn't actively interfere with any other service, the second assumption might as well be incorrect
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<Artyom>
DocScrutinizer: BTW Have you heard about very similar situation with GLONASS+GLOBALSTAR like with GPS+lightSquared.
<DocScrutinizer>
nope
<DocScrutinizer>
never heard of globalstar either until now
<DocScrutinizer>
all this brought to my attention by whitequark - thanks for the pointers :-D
<Artyom>
It works in L-band also. It's frequencies are aproximately from 1610 to 1625 for uplink. (And GLONASS previously used frquencies up to 1609.4 MHz, but now up to 1605,4MHz)
<Artyom>
And maximum power of user terminal is up to 26 dBm...
<chrisb>
interesting
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<whitequark>
DocScrutinizer: fun fact: here, if someone says "smth is of German quality", then s/he means THE quality
<whitequark>
like for example there are still some metalworking machines in basements of Moscow State University, which originate from 1940's
<whitequark>
they still work and are actively used
<DocScrutinizer>
yeah, some time ago we had a record for building that class of stuff
<DocScrutinizer>
even more fun fact: here the almost same term is "Russian tank"
<whitequark>
rofl
<DocScrutinizer>
it works like a Russian tank
<DocScrutinizer>
or is built like one
<DocScrutinizer>
not very commonly used term though
<DocScrutinizer>
also usually implies you need a hammer to start the unit
<whitequark>
very true indeed
<whitequark>
there are a whole lot of Soviet-era tales about different kinds of equipment which won't work unless kicked mercilessly
<whitequark>
supercomputers, icbms, etc.
<whitequark>
there's a thing I miss about that, through. each device came with the full printed schematics, even ones as complex as TV's
<whitequark>
and you could just get your soldering iron and fix it if it has broken
<whitequark>
there are still chunks of solder sold marked as "for domestic use"
<whitequark>
(through I don't really get how you could fix a TV with a soldering iron where tip d=8mm and a cylindrical chunk of solder d=12mm)
<roh>
whitequark: that was that way in western europe too. something like 30-40 years ago
<roh>
i have repaired radios from then (with tubes) which even had the schems on the backpanel
<DocScrutinizer>
err radio with electron valves, 40 years old?
<DocScrutinizer>
NAH! ;-)
<roh>
DocScrutinizer: yes. sure
<roh>
but the majority is older. youre right there
<DocScrutinizer>
40 years ago all radios had transistors
<DocScrutinizer>
30 years ago for sure
<DocScrutinizer>
new ones
<DocScrutinizer>
of course there were 40 year old valve radios 40 years ago ;-)
<DocScrutinizer>
but yeah, that schematics inside the device were a nice surprise whenever you opened one of those
<DocScrutinizer>
when you were lucky, they didn't fall apart on unfolding them :-P
<DocScrutinizer>
I think they stopped that habit after several houses burnt down XP
<DocScrutinizer>
then the schematics came with the user manual
<DocScrutinizer>
btw a contemporary fridge of a friend of mine came with a user manual with schematics, marked "for Spain only"
<DocScrutinizer>
maybe there it's still mandatory to ship schematics with some classes of appliances?
<DocScrutinizer>
oh sure, on electric stoves you still frequently see schematics
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<whitequark>
DocScrutinizer: burnt down XP?
<DocScrutinizer>
XP == emoticon
<DocScrutinizer>
like :-P ++
<DocScrutinizer>
maybe better: X-P
<DocScrutinizer>
rather like ;-P * 2
* roh
must admit he started to like pioneer hifi stuff lately. somehow i can find service manuals online as pdf a lot
* wpwrak
had a valve radio some 35 years ago. mono. a bit bass-heavy but smooth sound if i recall correctly. i think that was the last critter with such technology in our household. i think the B&W tvs already had transistors
<whitequark>
err, the accompanying text was in Russian, but approximately this: "a part of L^2's occupied spectrum reaches the L1 band and interferes with M-signal"
<whitequark>
the M-signal is IIRC the high-precision military code
<DocScrutinizer>
from " 3 GPS Satellite Signals" in menu of first link
<DocScrutinizer>
can't find M-code
<DocScrutinizer>
but yeah, P-code is "precision code" which probably is not used in regular consumer grade devices
<DocScrutinizer>
for your convenience: >>The P-Code (Precise) modulates both the L1 and L2 carrier phases. The P-Code is a very long (seven days) 10 MHz PRN code. In the Anti-Spoofing (AS) mode of operation, the P-Code is encrypted into the Y-Code. The encrypted Y-Code requires a classified AS Module for each receiver channel and is for use only by authorized users with cryptographic keys. The P (Y)-Code is the basis for the PPS.<<
<DocScrutinizer>
PRN == Pseudo Random Noise (iirc)
<kristianpaul>
lightsquared, sqaured, well, we need more cools applications around L1 Band
<kristianpaul>
s/sqaured/squared
<qi-bot>
kristianpaul meant: "lightsquared, squared, well, we need more cools applications around L1 Band"
<kristianpaul>
I'm not totally sure but you should confirm the lenth of that cryptographic bits to be sure is something worth to be classified :-)
<kristianpaul>
lenght*
<kristianpaul>
sure is 7 days... i mean in the navigation message
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<wpwrak>
DocScrutinizer: fun problem: assume you want to design a digital probe (for a logic analyzer). it should be high-impedance (>= 1 MOhm), good up to at least 200 MHz, operating at 3.3 V (but larger input range desirable). probe and cable should be as small/thin as possible. also, the thing should be very low-cost. to the point that you can consider it disposable. how would you do it, with industrially available components ?
<wpwrak>
DocScrutinizer: i.e., would you make the probe active ? if yes, how to keep the cable thin ? or passive ? if yes, how to maintain the high impedance ?
<wpwrak>
DocScrutinizer: would you go directly to the LA (maybe 1 m away) or to a bridge board close to the circuit with additional circuit ?
<wpwrak>
(the bridge board could be more complex/expensive. of course, better if it's not needed)
<wpwrak>
as far as "small" is concerned, ideally below 2.5 mm wide/diameter
<wpwrak>
less if possible :)
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<wpwrak>
the simplest would be just a coax, with a FET at its end. then measure the current. but ... how much power does it have to burn ? if i model this as a low-pass RC filter with 10 pF parasitic, it would seem, quite a lot. in the order of 80 Ohm -> 130 mW
<DocScrutinizer>
bridge board, with ~10cm passive wires to DUT
<DocScrutinizer>
and I don't follow your power evaluation, the FET either is closed then n Volt * 0 Ampere, or it's open then 0.0n Volt * ~10mA
<DocScrutinizer>
the main power dissipation only happens during switching
<DocScrutinizer>
which ideally takes no time at all :-)
<wpwrak>
if closed, you'd still need to send a current through it to detect it. and that current would work against parasitic capacitance.
<wpwrak>
that would be a single FET, not a pair
<DocScrutinizer>
??
<wpwrak>
i.e., open drain
<DocScrutinizer>
sure, what else
<wpwrak>
the pull-up resistor (on the bridge board) would need to pull the signal up quickly enough
<DocScrutinizer>
yeah sure
<DocScrutinizer>
you usually use current source termination for that
<DocScrutinizer>
I.E. a PNP with a emitter R and basis to a common constant voltage
<DocScrutinizer>
via that common constant vltage you can tune your circuit to give proper rise time with arbitrary parasitic C load (coax cable length) and still not consume more power than needed
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<wpwrak>
hmm, that would be considerably more than just a FET at the probe, no ?
<DocScrutinizer>
the emitter R typically is very low, like maybe 10 Ohm
<wpwrak>
and more than GND plus signal, too. i.e., you'd have at least also a supply voltage
<DocScrutinizer>
the current source is at your bridge board
<wpwrak>
is there another name for each a circuit ?
<DocScrutinizer>
the probe has just the FET, maybe a gate pulldown R
<wpwrak>
s/each/such/
<qi-bot>
wpwrak meant: "is there another name for such a circuit ?"
<DocScrutinizer>
or pullup
<wpwrak>
i googled for it and what i found has a current source at the sender and a comparator at the receiver
<DocScrutinizer>
so your FET in probe is from collector of that constant-current source (inner of coax) to GND (shield of coax)
<DocScrutinizer>
R1/R2 probably common for all N probe inputs of your bridge board
<DocScrutinizer>
and make it a poti
<DocScrutinizer>
so you can tune the current like I mentioned above
<wpwrak>
;-)
<DocScrutinizer>
Re is very low, you want the current source be able to deliver some nn mA to a voltage very close to the emitter voltage
<DocScrutinizer>
or you add in a voltage limiter
<DocScrutinizer>
simplest case: a Zener
<DocScrutinizer>
this way you can define the voltage at FET's source and thus the logic level where it will detect a 1
<wpwrak>
hmm, pwm-drive the supply voltage ?
<DocScrutinizer>
of course a simple clamp diode to a constant voltage source common to all probe inputs would be way more versatile and cool
<DocScrutinizer>
the basic benefit regarding current source of such a clampdiode+CV is that your supply voltage for the current source (at Re/emitter) can be several volts higher than the probe high-level voltage, thus guaranteeing that your current source will properly pull up with full current until high level get reached
<wpwrak>
hmm, that would be for M1. we have a 5 V supply. and signals (to the M1) are 3.3 V
<DocScrutinizer>
your parameters for the evaluation then are: 1/(200MHz *(2 + 1for_margin)) rise_time; 10 pico As/V parasitic capacity; 3.3V high level; solve for current needed
<DocScrutinizer>
calculate with 100pF max C_parasit, and evaluate the Re for the resulting needed current @ 5 - 3.3 V
<DocScrutinizer>
then you reduce that current via R1/R2
<wpwrak>
1.6 ns rise time. hmm, what kind of FET has that ?
<DocScrutinizer>
HF FET?
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<wpwrak>
aah, right. RF FET is the product category :-)
<wpwrak>
kewl, and they go up to 7 A ;-))
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<wpwrak>
if i have a FET in the probe, is it safe to have a probe cable > 10 cm. e.g., 50-100 cm ?
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<DocScrutinizer>
sure, why not
<DocScrutinizer>
all your probes should have same length though, to eliminate propagation delay diffs
<wpwrak>
yeah, it would be tragic to get that bit wrong :)
<DocScrutinizer>
your signal will move along the coax to the "bridge" at typical cable specific sub-light-speed, and arrive there in the same shape and sequence you fed them into the cable with your FET. Theoretically the cable could be 100s of meters length, and several signal edges traveling along it
<wpwrak>
very good. now, to find a really thin coax cable ...
<DocScrutinizer>
of course you want to terminate the coax with the right R, to avoid reflections
<DocScrutinizer>
since your current source is basically zero impedance, your termination will be series to cable
<DocScrutinizer>
this kinda actually defeats the purpose of the current source somewhat, but meh
<wpwrak>
;-)
<wpwrak>
i wonder how all those terminations of data lines really work. e.g., to RAM address lines. those inputs don't look like zero impedance to me.
<DocScrutinizer>
assuming your current source is set to deliver less than 50R/3V3 Ampere, it seems still like a good design to me
<DocScrutinizer>
oh yeah, now it makes sense when my colleague informed me that the Lauterbach debug connector cable is some 200EUR - it's two 16wire flat cables with coax, about as thin as the one you dug up there. ~10cm length, with two nasty plugs, one each end
<whitequark>
I called the module, answered the call on it and hold it for a minute or two
<whitequark>
it's hardly warm
<whitequark>
*held it. not in the telco sense, just left my phone lying with the call going on
<DocScrutinizer>
whitequark: you can't really control the OTA situation, so you have no clue how much of its theoretical 100% power the TX actually had to use for your 1min call
<DocScrutinizer>
if you didn't talk, odds are it didn't send much at all (silence TX cancellation)
<DocScrutinizer>
when you're close to the BTS, odds are your TX worked with power correction factor like *0.0001 or sth
<DocScrutinizer>
there'S basically no decent way to test those things, that's why a decent datasheet mentions the heat sink requirements of such a component. They have means to test worst case at that fab where those modules got developed
<DocScrutinizer>
silence TX cancellation probably aka pasue compression or sth like that
<DocScrutinizer>
pause*
<DocScrutinizer>
basically means that TX doesn't wase power to TX data that's just transporting silence
<DocScrutinizer>
waste*
<whitequark>
well, this datasheet is indeed not "decent"
<whitequark>
and I indeed did not talk
<whitequark>
hm
<whitequark>
would a microwave oven work?
<whitequark>
that is, I put the module in the (turned off) oven which is basically a faraday cage
<whitequark>
and then open it a bit
<viric>
oh
<viric>
microwave
<whitequark>
viric: wat?
<viric>
I was waiting for the time when microwave ovens appear at #qi-hardware
<viric>
;)
<whitequark>
what's so special about them?
<viric>
they can kill
<whitequark>
indeed
<whitequark>
almost anything can kill, if used properly
<viric>
nicer, if killing with open hardware
<whitequark>
well, you indeed need to keep it open to kill anyone...
<viric>
:)
<viric>
sorry for the pause in your conversation. go on go on
<whitequark>
nah, I said whatever I wanted
<viric>
Isn't there any kernel patch that can make the kernel remember the backlog buffer of every virtual console, regardless of switching'
<viric>
?
<viric>
is this so high tech?
<whitequark>
oh, just go to lkml and troll them a bit
<whitequark>
faster than just asking
<viric>
hm could work
<viric>
I've a 80x25 console, switched the vc, and I lost my valuable 8KiB of backlog... what is this trying to optimise?!
<whitequark>
memory consumption?
<whitequark>
that is
<viric>
on a 7MB kernel?
<whitequark>
the consumption of users' memory by this behavior
<viric>
haha
<viric>
modprobe pcspkr takes more memory
<whitequark>
sigh. DCD is "circuit 109", and DTR is "circuit 108/2"
<whitequark>
crazy telcos
<whitequark>
where's circuits 0..99 ?
<viric>
100 is a good start for a three digit number
<whitequark>
why not 000 ?
<viric>
that may mean writing %03i instead of %i
<whitequark>
I could argue that DCD and DTR were invented before printf
<whitequark>
yea, RS232 is of 1969
<viric>
history is full of coincidences
<DocScrutinizer>
whitequark: yes, a good idea, just don't open it. You won't believe it but microwave ovens are all but tightly sealed for 900/1800MHz
<viric>
DocScrutinizer: the magic space frequency of the grid of holes of the front door
<whitequark>
DocScrutinizer: er. did I understand you correctly? microwave oven kills 2.4g but allows 900m/1800m to pass?
<DocScrutinizer>
yes
<whitequark>
huh
<DocScrutinizer>
lamda/2 seals
<whitequark>
but won't lambda/2 seal it for lambda*2 ?
<DocScrutinizer>
maybe they're caled lamda/4 seals, dunno. but yes, they should also work for subharmonics
<DocScrutinizer>
so 2400/2, */4, etc
<whitequark>
hm, I meant a bit different thing. if my math is any good, then λ(2.4g)=.125m, and λ(1.8g)=.166m
<DocScrutinizer>
whatever
<whitequark>
why would holes made to seal .125m pass .166m?
<DocScrutinizer>
not holes
<viric>
the cage size
<DocScrutinizer>
resonating gap between door and case
<whitequark>
oh. so it isn't sealed tightly?
<DocScrutinizer>
not at all
<whitequark>
... weird. I'd rather not stand near microwaves anymore
<DocScrutinizer>
hehehe
<whitequark>
well, at least it explains why 900m/1.8g escapes
<DocScrutinizer>
yup
<whitequark>
hm, but why gap and not a close connection?
<DocScrutinizer>
then place some electric toothbrush or whatever into the oven as well, to make some noise the phone can transmit
<DocScrutinizer>
very first microwave had seals. They were extremely expensive, unconvenient, and easily broke by a simple 0.5mm of random dirt between the elastic metal fibre and the case frame
<whitequark>
hm, so the sealed approach requires seal to be maintained at all times or the radiation would escape
<whitequark>
and the gapped one allows for any shit to accumulate in the gap as long as it's precisely the required size
<whitequark>
cool
<whitequark>
can you also explain this... if I'd put a %metal_thing% to an oven and turn it on, I'd get a nice discharge and a small lake of molten metal
<whitequark>
but if I put a %metal_cup_for_microwave% into it, I won't see any of the effects. it won't get even slightly hot
<whitequark>
why?
<whitequark>
I never really understood this
<viric>
there is a 'metal cup for microwave'?
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<whitequark>
yeah
<viric>
I've never seen one
<whitequark>
google for "microwave compatible metal [cup]"
<whitequark>
you can run arbitrary code on the CPU of this module
<whitequark>
well, "SIMCom Core Software and Embedded Application manage their own RAM areas. Access from
<whitequark>
one of these programs to another’s RAM area is prohibited and will cause fatal error.
<whitequark>
but it's still interesting. I bet they have quite a few holes there
<whitequark>
you can also easily downgrade firmware, nothing prevents you from doing that
<DocScrutinizer>
whitequark: depending on architecture, you hardly will find any hole
<whitequark>
ARM926EJS
<whitequark>
afaik it's embedded in an ASIC
<DocScrutinizer>
on STE modules we have PSEL and PSEL_SECURE to access peripherals in secure and unsecure mode. Same for RAM access
<whitequark>
"The ebdat4_04Wdtkick function kicks the watch dog."
<whitequark>
poor animal :/
<DocScrutinizer>
we got 3 ARM cores, one for network stack (aka GSM/LTE/*), one for communications between all the subsystems on SoC, and one App core
<whitequark>
in this case, looks like everything is running on the single core
<whitequark>
well, at least that's what I think after looking at a vast amount of docs
<DocScrutinizer>
and even the 4words deep FIFO 5 chan "mailbox" function block has 3 nonsecure and 2 secure channels
<DocScrutinizer>
our customers never get to know about NS and COM core or the functions/processes running there
<whitequark>
err, I bet the "display interface" present in this module is made for Nokia 3310 display or equivalent one
<GNUtoo>
ah baseband....
<GNUtoo>
what about that:
<DocScrutinizer>
they might think the whole M7400 modem SoC has just one ARM core to run some general purpose things like AT interpreter and their custom 'apps'
<DocScrutinizer>
and thus find out where you are, without GPS
<whitequark>
err, it has such a command
<DocScrutinizer>
given you got an idea about where BTS are
<DocScrutinizer>
I'd probably not try to do this during a cal, though in theory it should work (and call shouldn't stall)
<DocScrutinizer>
dang, is this actually already 4 years in the past?
<whitequark>
hm, how do I get GK readings?
<whitequark>
*G-K
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<whitequark>
DocScrutinizer: huh, google can locate by cellids
<DocScrutinizer>
those are special for O2-germany I guess. They are via cellbroadcast SMS channel 221 here
<whitequark>
and there's a db of Russian cellids
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<DocScrutinizer>
wow, so from google we get location of the BTS
<whitequark>
actually your technique is very well known in Russia. there's even an article in "Hacker" (it's the name) journal, which means that a pretty big amount of people knows about it
<whitequark>
yeah, google collected cellids too, apart from wifi ones
<whitequark>
it's quite obvious thing to do I'd say
<DocScrutinizer>
now get TA for 3 or 4 cells (current servicing cell, plus 3 neighbour cells via theis command to select/lock to them) and you got your distance to 4 points on globe
<whitequark>
heh, very interesting. I wonder how precise can this be
<DocScrutinizer>
whitequark: location to a circle around your serving cell is very common and widespread. The triangulation with 3 or 4 or 5 cells however probably isn't as it needs that command you found
<whitequark>
DocScrutinizer: (widespread) I meant the location with a netmonitor tool. there's a lot of stuff on local forums about this
<DocScrutinizer>
hmm
<DocScrutinizer>
whatever, this module is the first one I get to know of, that can do automatic forced cell reselect
<DocScrutinizer>
alias Cell-lock
<DocScrutinizer>
usually modems offer neither engineering mode and for sure not cell-lock
<whitequark>
usually modems don't allow you to change imei arbitrarily
<DocScrutinizer>
that too :-)
<whitequark>
well ok, I can source a bag of these if someone wants
<whitequark>
not a problem, a local supplier will happily sell me any quantity I'd want
<whitequark>
complete with custom fw upgrades service and whatnot
<DocScrutinizer>
well, you could do some sort of improved-location via triangulation when you monitor the the modem closely for service cell data and catch the values at moment of handover from one cell to another. So you get at least 2 cells with distances to them in that moment, which allows a location to something like a parallelogram with 550m sides
<DocScrutinizer>
atually 2 parallelograms, one for 'left' and one for 'right' side
<DocScrutinizer>
unless you're on the line between those 2 BTS
<DocScrutinizer>
and are lucky enough so sum of TA just matches distance between them
<DocScrutinizer>
in which case you get only one parallelogramoid
<DocScrutinizer>
or actually a section of two circles in that special case
<DocScrutinizer>
a very small one
<kristianpaul>
argh, hate race conditions
<whitequark>
DocScrutinizer: I could also use rssi
<whitequark>
as in "random signal strength indication"
<DocScrutinizer>
??
<whitequark>
for distance measurement
<DocScrutinizer>
distance from signal strength? muhahaha
<whitequark>
or, hm, maybe not
<whitequark>
for wifi that did not make much sense
<DocScrutinizer>
maybe in an ideal world
<DocScrutinizer>
without trees and without buildings
<DocScrutinizer>
and with ideal antenna on your phone
<DocScrutinizer>
and of course without you covering half the perimeter of sight from that antenna
<DocScrutinizer>
look at the dB values for neighbour cells from the post I linked above. Do they look like steady or correlated to the TA value that *really* gives distance OTA to BTS?
<whitequark>
ok ok I understood it :)
<DocScrutinizer>
esp look at that pair of neighbour cell readouts where I moved just 3 meters
<DocScrutinizer>
chan:706, max:-35dB, min_-62dB -- device moved by 60cm(!)
<whitequark>
DocScrutinizer: btw that trick is confirmed not to work during call
<whitequark>
it just displays one BTS in the +CENG URC
<DocScrutinizer>
well, that's just enough, as we're not interested in neighbour cell data once we got the channels. We're just 'roaming' to the next cell by forcing it with that command you found
<DocScrutinizer>
and that shouldn't (but might nevertheless) interrupt the call
<whitequark>
ah. hm, I'll test
<whitequark>
hm weird, it just stopped displaying neighbour cells
<whitequark>
simple, I forgot to remove celllock
<DocScrutinizer>
I think I like to get one or two of those nice modules :-D
<whitequark>
no problems. email your postal address at whitequark@whitequark.org then
<DocScrutinizer>
sure thing
<whitequark>
not sure what method should I use to send them, through
<whitequark>
first-class mail? dhl?
<DocScrutinizer>
hmm, usual letter?
<whitequark>
three words: "Russian Postal Service"
<whitequark>
I bet they have a 10-ton press for these or whatever
<whitequark>
maybe they run with the truck over letters
<DocScrutinizer>
:-S
<whitequark>
(apart from the fact that 12g may be a bit too heavy for a "usual letter". and the electronics inside will arouse customs)
<DocScrutinizer>
nah, 12g are fine
* whitequark
never sent these in his entire life
<DocScrutinizer>
usual letter is either 20 or 50g max, can't reacall
<DocScrutinizer>
well, whatever you think may work best
<whitequark>
hm ok. I think I'll send them maybe at next Sat
<DocScrutinizer>
no hurries
<whitequark>
... you have some Australian friends, don't you? :)
<DocScrutinizer>
er, kinda
<DocScrutinizer>
Raster comes to mind, but he's probably in Korea most of the time
<DocScrutinizer>
why?
<kristianpaul>
12g!! is not heavy IMHO
<whitequark>
DocScrutinizer: "not worries" is a purely Australian English expression afaik
<DocScrutinizer>
ooh, didn't know that
<whitequark>
that's what I thought of reading your message
<kristianpaul>
btw this module you talking about is a modem?
<whitequark>
kristianpaul: yeah. AT interface, analog I/O
<whitequark>
it can GPRS, through, and has full TCP/IP stack inside
<whitequark>
even with HTTP&FTP
<kristianpaul>
does it work with the nanonotr
<kristianpaul>
ahh too bloated (HTTP&FTP)
<kristianpaul>
ok
<kristianpaul>
:)
<whitequark>
er
<whitequark>
you can omit using that
<whitequark>
just use it as a dumb modem with pppd
<kristianpaul>
yeah, i was thinking in that
<whitequark>
I'm sure NN has an uart
<kristianpaul>
soon or later i need som kind of gprs/edge/3G/ for my nanote
<kristianpaul>
some*
<DocScrutinizer>
no 3G
<kristianpaul>
edge?
<whitequark>
but! I seriously doubt its battery can provide the required 2A peak@3.3V (actually 2.7V-4.8V)
<whitequark>
no edge
<DocScrutinizer>
this is 2.5G aka EDGE
<kristianpaul>
wtf 2A!!
<whitequark>
that's GSM
<whitequark>
2A _peak_
<kristianpaul>
yeah, not my field..
<whitequark>
in idle mode it eats 1.5mA
<whitequark>
in tx/rx that may be in range of 10mA-200mA avg
<kristianpaul>
had you tried make it work?
<kristianpaul>
with the nanonote and pppd
<whitequark>
I don't have NN
<kristianpaul>
WHAT?!
<kristianpaul>
;-)
<DocScrutinizer>
me neither
<whitequark>
tuxbrain is kinda slow on delivery
<kristianpaul>
I tought, you... all this time
<whitequark>
well no
<kristianpaul>
OMG still delivering?
<whitequark>
yeah, more than 2 months
<kristianpaul>
oh well..
<whitequark>
I mainly want it as a testbed for 6lowpan
<whitequark>
not that I have much use for NN apart from that
<whitequark>
I have an Android phone
* whitequark
hides from DocScrutinizer
<kristianpaul>
ergh, i havbe dumb phone
<kristianpaul>
but need at least gprs for mutt and irssi when a hurry
<whitequark>
this module is basically what's inside your dumbphone, but without keyboard and screen
<kristianpaul>
rss reader will be cool to
<kristianpaul>
size?
<whitequark>
seriously, you can just add some buttons and a display, and it'll be nokia 3310
<kristianpaul>
i have a sim548 too big
<whitequark>
33x33x3mm
<kristianpaul>
built-atenna?
<whitequark>
nope
<kristianpaul>
ah
<whitequark>
but you can attach any easily if you know how to solder
<whitequark>
srsly, not much of a problem
<kristianpaul>
yes i supose i do :)
<kristianpaul>
well, i'll wait for lightsquare satellites to deploy, lol
<DocScrutinizer>
aen't those already flying?
<kristianpaul>
i guess so, but enought to cover worldwide?..
<DocScrutinizer>
no way
<whitequark>
because?
<kristianpaul>
will crash with GPS ones ;)
<kristianpaul>
(kidding)
<whitequark>
that's the privilege of russian sats
<whitequark>
there was some funny/horrifying story (depending on whether you are a telco engineer) when one of russian sats malfunctioned and kicked an Iridium sat off the orbit
<DocScrutinizer>
hey yeah, we 'recently' had some collision up there X-P
<whitequark>
DocScrutinizer: huh? another one?
<kristianpaul>
decay all days :)
<DocScrutinizer>
I only know of one, can't recall details, but the crash generated like 35000 new tiny objects that all need to get monitored by NASA or whoever is responsible for that
<whitequark>
yep, it's that one
<DocScrutinizer>
they wait for a chain reaction on next or the crash after that
<whitequark>
the count of objects is 500-600 through
<DocScrutinizer>
depends on size where you start to call it an object, I guess
<DocScrutinizer>
maybe the trackable ones are actually only 500
<DocScrutinizer>
the real headache are those you can't track as they are too small to find them with radar
<kristianpaul>
where is(are) that radar(s) btw?
<DocScrutinizer>
NFC, ask NORAD or NASA
<kristianpaul>
;)
<DocScrutinizer>
NORAD probably
<DocScrutinizer>
>>Die Überwachung schließt von Raketen übrig gebliebenen Weltraumschrott sowie das Aufspüren, Validieren und Warnen vor Angriffen auf Nordamerika mit Flugzeugen, Raketen oder Weltraumfahrzeugen ein.<< http://de.wikipedia.org/wiki/North_American_Aerospace_Defense_Command
<kristianpaul>
urgh that sword scares..
<whitequark>
phallic symbol
<DocScrutinizer>
>> To accomplish the aerospace control mission, NORAD uses a network of satellites, ground-based radar, airborne radar and fighters.“ – www.norad.mil — About. Aufgerufen am 17. Juni 2010 <<
<whitequark>
mhm. "airborne radar and fighters"?
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<DocScrutinizer>
>>Aerospace warning includes the monitoring of man-made objects in space, and the detection, validation, and warning of attack against North America whether by aircraft, missiles, or space vehicles, through mutual support arrangements with other commands.<<
<DocScrutinizer>
allegedly playing chess is also one of their duties
<DocScrutinizer>
;-)
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<wpwrak>
kristianpaul: i would worry more about the headless chicken