[greenhorn]

I was talking from the Digital Radio signal transmission perspective. look at digital TV reception. In analog, when it rained / there was interference to the signal, the picture became granier and grainier until it it became just an outline. With digital, the artefacts ruin entire parts of the picture completely, until the picture stops altogether.
PS : apologies to sam for the thread hijack. maybe the mods can move the discussion on digital communication to another thread

[Samurai]

Originally Posted by greenhorn

I was talking from the Digital Radio signal transmission perspective. look at digital TV reception. In analog, when it rained / there was interference to the signal, the picture became granier and grainier until it it became just an outline. With digital, the artefacts ruin entire parts of the picture completely, until the picture stops altogether.

Boss, we are talking about wired media used in telephones. Sam gets his MTNL service over the same wires we are discussing. Basically it gives him more ammunition when he has to deal with MTNL next. And you go off talking about satellite TV reception which is completely off-topic. Completely different media, different traffic, different dynamics. Now Sam will be really pissed.

Originally Posted by Sam Kapasi

You techie guys have ruined my thread :(

Well Sam, your thread has run it's course, now the thread has gone deeper into specifics of telephony wires, etc. Greenhorn has already apologised for hijacking it to discuss satellite TV reception. Now we will get back to telephony and Internet over telephony lines. I am good at the former, I wish somebody else can discuss the latter.

[greenhorn]

Aight then, back to some more of of MY BSNL woes.

The copper pair to my house has only ONE pair which seem to be fit to carry the ADSL signal.With it , i get about 27 dB SNR , and operation is stable. but then , the guy next door gets a crackling phone line. So he complains and the lineman finds my neighbours fault to be due to a bad copper pair , and -hey look, there is a perfectly fine one right next to it ! I come home and find my connection spradic, and SNR is below 10 dB . Some calls ensue and within a week, I get the good cable pair. Then the whole story repeats itself. We've tried to talk about this to the JTO at the exchange, even tried escalating it. Every time , they give me the good line , and say, It's working , aint it ? and leave , and it works till the day my neighbour decides to call the lineman. My house is at the end of a lane , so they dont want to bother fixing it either.

[tsk1979]

I can talk ADSL all day and all night. As for everything else, its upto you Samu
greenhorn, ADSL is carried over higher frequency(Sound is below 8KHz).
in the 8-30KHz band, you get more susceptible to things like "induction loops", "bad wiring" etc.,
So for improving your 10dB SnR, you have to get the line changed.
If thats not possible, disconnect the splitter.
Am ideal splitter would send 0-8KHz to the phone, and 8-30KHz to the modem. But this is not an ideal world, so splitters rob you of 3-4dB atleast.
So when you get the bad line, till they fix it, use without splitter(you will lose your phone though!)
The permanent solution is not to use BSNL/MTNL as I discovered.

[Thad E Ginathom]

Originally Posted by Hurrycane12

This is a sure way of learning for non techies like me

Even for us ex-techies who once knew what to plug in where, but not much about how it worked!

Originally Posted by vid6639

Nope. Ethernet or LAN is digital. Depending on cable the length can go upto 500metres.

Ethernet is only one kind of LAN, although it is more or less the defacto kind these days. IBM used to install lengths of railway line around your office, and a little train used to chug from machine to machine. If it was empty, a machine could load it with a packet of data to send to another machine --- or something like that

Originally Posted by vivekiny2k

quoting condor's signature, "life is analog, digital is approximation".

what if you get a .3 lux on optical fibre assuming 1 lux is supposed to be 1, and zero lux zero? proves that the medium is analog.

Yes... not as simple as on/off. I thought as much.

What if I telephone you, and read out some data in digital to you: "one, zero, one, one, zero, zero, zero, one....", Is the data I'm transmitting digital or analogue?

Originally Posted by Sam Kapasi

You techie guys have ruined my thread :(

I am sure your literary skills can fix that soon enough!

[Steeroid]

Originally Posted by Sam Kapasi

You techie guys have ruined my thread :(

What thread? Its all wires and cables here now.

I think they are agents sent in by MTNL.

[Samurai]

Originally Posted by tsk1979

ADSL is carried over higher frequency(Sound is below 8KHz).in the 8-30KHz band, you get more susceptible to things like "induction loops", "bad wiring" etc.,

If ADSL is just 8-30KHz, how am I getting 2048KHz internet bandwidth?

[vivekiny2k]

Originally Posted by Thad E Ginathom

What if I telephone you, and read out some data in digital to you: "one, zero, one, one, zero, zero, zero, one....", Is the data I'm transmitting digital or analogue?

trying to imagine how the conversation will go on.

[Thad E Ginathom]

NAK


Oh dear; now I have to break a forum rule!

[mmmjgm]

Originally Posted by Samurai

If ADSL is just 8-30KHz, how am I getting 2048KHz internet bandwidth?

Sorry to bump into the heated techie discussion being an accounts guy am not very much into finite telecom technology.

However Samurai are you equating 1khz = 1 kbps ? Is that what you are trying to say ?

Bytes and Kbs are volumes of data, is the transmission dependent on the frequency of the connection ? i.e. higher the frequency higher the throughput ?

Do clarify this doubt.

cheers

M M

OT what a massacre of the original thread !

[Cyrus43]

I used to have some godforsaken 199 scheme in which i used to get a dwload speed of atleast 75-150 Kbps. my bill used to be in the region of around 5000 Bucks a month including the phone charges. On friday i have shifted to the 2Mbps scheme and it is useless!!! I am getting in the region of 10-30 KBps Dwld Speed. My torrents take ages to download and limewire which used to be blitzingly fast now bores me!!!

[vivekiny2k]

Originally Posted by Cyrus43

my bill used to be in the region of around 5000 Bucks a month including the phone charges.

whoa, I pay around 100$ for digital cable plus internet, 400+ kbps real life download speeds on torrents. Didn't know india is still costly when it comes to internet.

[Samurai]

Originally Posted by mmmjgm

However Samurai are you equating 1khz = 1 kbps ? Is that what you are trying to say ?

If you are talking circuit switched or telephony, it would be roughly same, one has to account framing bits, etc. It is approximate, unlike analog this is not a wave form, well... it is a collection of various harmonics. Hmm, let's not get deeper into fourier analysis here. Besides, I don't remember those theories anymore.

But in packet switched data, as in Internet traffic, the payload kbps will be less than KHz, that is because of the framing/header/error-correction/etc info needed in datalink, network and transfer layer. If the link is more error-prone, the kbps will be much lesser than KHz.

Before any audio guys jump up and say that's not true, KHz should be less than kbps, we are talking about the raw KHz of the link, not the KHz of the music file before PCMing it.

[tsk1979]

Originally Posted by Samurai

If ADSL is just 8-30KHz, how am I getting 2048KHz internet bandwidth?

Originally Posted by mmmjgm

Sorry to bump into the heated techie discussion being an accounts guy am not very much into finite telecom technology.

However Samurai are you equating 1khz = 1 kbps ? Is that what you are trying to say ?

Bytes and Kbs are volumes of data, is the transmission dependent on the frequency of the connection ? i.e. higher the frequency higher the throughput ?

Do clarify this doubt.

cheers

M M

OT what a massacre of the original thread !

Oops my bad!
Its actualy 25KHz-138KHz for upstream and and upto 1108KHz for downstream in standard ADSL!
So its actually 25KHz-1.1MHz and not 30KHz

[Samurai]

So mine is not standard ADSL then.