Why do cell phones have no crosstalk? (and other questions)

I just replaced my old Motorola analog flip phone (#550) with a new digital phone.

I'm disappointed in the sound quality. The analog phone had reasonable sound quality and some crosstalk. The new Motorola digital phone sound is "choppy", as if someone has sliced off bits of the signal. (figuratively and literally). If the other party isn't speaking clearly directly into his phone, it becomes garbled. There is no cross talk at all, and often in the conversation I wondered if we were still connected.

Also, the analog phone had a big LED display that clearly showed signal strength and battery power. The new phone has very tiny little symbols I could barely see.

Is this typical of today's digital phone quality?

Do new digital phones give a warning signal before the battery runs out? My analog did with the older style battery but not with the newer style premium battery.

They say I should "cycle" the battery--charge and discharge. Could someone elaborate?

Thanks!

Reply to
hancock4
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Run the battery down to full discharge and then recharge several times to prevent memory.

Reply to
Steven Lichter

The battery was only partially charged upon receipt. Should I charge it all the way up first, or run it down first?

Thanks again!

Reply to
hancock4

Welcome to digital: low quality sound, dropouts, and latencies so high it's hard to carry on a normal conversation. Sure it sucks, but it's cheap. It's impossible to underestimate the desire of the American public to sacrifice quality in return for quantity. I think television has pretty much proven that beyond doubt.

That's because they did. The more simultaneous calls they cram into their allotted bandwidth, the lower the costs are and the higher the profits are. As you increase calls/MHz, you decrease sound quality. So they go to lower and lower bit-rate codecs and allow more and more simultaneous calls. As a result, digital cellular sounds like crap compared to a quality analog phone.

It'll keep getting worse until it gets to the point where it's hurting sales and causing customer to flee to providers with higher quality connections (if there were any). I have little hope that things will change since there doesn't appear to be any significant market pressure on the providers to provided decent connection quality.

Reply to
Grant Edwards

[sigh]

As an aside, I remember all the grand claims they made for cable TV, how educational and cultural it would be. It turned out to be lots of commercials (more than broadcast), lots of reruns, and lots of tabloid junk. One "educational" channel now runs boob jobs all day long.

I'm afraid most consumers don't know or don't care. After all, many have installed cheap crappy landline phones in their homes where the quality was far worse than Western Electric 500 sets. Someone once said to me, "You sound very clear. What kind of phone are you on?" I happened to be on a 302 set ("F" handset) from 1948, but that sounded better. So it goes.

The big carriers advertise like crazy they offer better quality but do they really?

Hmm, I wonder if I set my new phone to analog only if it will sound better.

So far I wish I hadn't switched, but the batteries on my old analog phone were shot. I used it mostly in the car off the adapter, which was my original intent all along. But there were times I wanted to have a phone with me.

Reply to
hancock4

It might, but the battery will die pretty quickly.

Most of the carriers are forcing analog customers onto digital plans whether they want to go or not. The carriers are going to pull the plug on analog service one of these years (I don't remember when, exactly).

Reply to
Grant Edwards

Verizon will kill analog in February 2008.

Getting back to the new battery of my phone, should I _first_ discharge it completely or charge it completely? It was delivered half charged. Thanks.

Reply to
hancock4

You'll get 50 different answers from 25 different people. Don't sweat it.

Reply to
danny burstein

Is it CDMA (Verizon or Sprint), GSM (Cingular/ATT or T-Mobile), or iDen (Nextel)?

It is my impression that GSM sounds slightly less awful because the channnels are of fixed size, as opposed to CDMA which can be adjusted dynamically to squeeze in as many as the signal conditions will support.

Re the battery, I agree, don't worry about it. I haven't observed much memory effect in recent phones, since the batteries are not nicads.

Reply to
John L

Mine told me to charge it 24 hours then discharge it 4 times to prevent memory effect. I would guess all new phones are about the same.

Reply to
Steven Lichter

I agree, my old Panasonic Bag phone being 3 watts worked just about everywhere, my Analog hand held being 1 watt also worked most of the time, my new Digital works almost the same, but I agree the sound does not seem to be as good and it a lot of areas when it goes roaming it is in Analog. But the batteries work longer and last longer then the old ones.

Reply to
Steven Lichter

Years ago the same was said when the IMTS phone, you know the large tube type phone in the trunk. Years ago GTE put one of their old systems back on the air for company use having found that even the Analog phones did not work right in the mountains. Don't know if it is still working as I have long since retired.

Reply to
Steven Lichter

Sigh. Tech writers.

NiMH batteries need a few cycles to get to full capacity, but this isn't memory. (Neither is what folks commonly call "memory" in nicad. That's technically voltage depression caused by overcharging the nicad. Real nicad memory is *fixed* by overcharging the battery.)

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And yea, my $20 Moto C139 came with a mostly discharged NiMH cell too. It took a couple of hours charging before I noticed that the phone said "charged". (Talk about wasteful pricing, it was cheaper to buy a second identical phone and charger package than buy a spare factory battery.)

-wolfgang

Reply to
Wolfgang S. Rupprecht

danny burstein skrev:

With the risk of giving you an 51st differing answer, I'd say it depends what type of battery and what type of charger you have. My personal rule of thumb for new rechargeable batteries (regardless of type) is as follows:

o Charge it completely, preferrably using a slow, "standard" type of charger (sadly though, most cellphones tend to come with rapid/quick chargers, but there are exceptions).

o Discharge it completely by normal use, i.e. use it as you intend to use it, until the device shuts down due to low batteries, at which point you plug in the charger and do step #1.

I always "break in" my new batteries this way the first half a dozen or so first charges, then I repeat the above cycle whenever I feel like my batteries need it (happens on average 1-2 times a month).

I also have the rule of thumb to avoid running a rechargeable device connected to a external powersource if I can avoid it, as it is my experience that it shortens the life of the battery. I've learnt this the hard way with my previous cellphone (a Nokia2110/GSM), and strictly following this rule with my new one (Nokia3110/GSM) gave me three years before I had to buy a new battery (though the age of the battery has been frustrating the last 6 months or so).

As to the sound quality of digital cell phones that was the topic a little earlier in this thread, I have two general tips I can give, which should be applicable to digital cell phone standards other than GSM (which is the predominant (if not only) standard here in Europe).

The first tip is to use an external antenna if you're in a car or in an area where the cell base stations aren't as densely packed as in cities. It has its basis in the fact any digital signal tends to have an abrubt quality drop when you reach low signal levels, and your description of the sound being "choppy" suggests (at least to me) that you might have a signal level problem, which can be resolved (within reasonable limits) by improving the signal strength by using some other antenna than the poor one built into the phone.

The second tip is one I read in a technical book about GSM. It has its basis in the fact that all digital cell phone services (not just GSM) use error correcting codes. Simply move the phone a little, directly or indirectly (by moving yourself), causing the bit errors to move about, making it easier for both your phone and the cell station to detect and correct the errors. I've used it myself, and 2" to 3" seems to be sufficient.

And since we're on the subject of cell phones, I have a question on an idea I have on resolving a signal strength issue of a friend of mine, whose flat apparently is located right in a "dead spot", cell-phone-wise. My idea is to direct a yagi antenna (with 15dB or so of amplification) towards a base station, but instead of connecting it to the phone, I'd like to connect it to a good quarter or half-wave antenna, located centrally in her flat. I'm not expecting miracles, only to have a spot within a handful of yards of the 1/2 or 1/4 wave antenna where reception is good.

The length of the cable between the antennas won't be more than 10 to 15 feet or thereabouts, so I won't expect the signal to drop more than a couple of decibels. Is my hunch correct, that it would give the cell phone signals an artifical path to follow, and thus improve the signal strength locally? Has anyone of you tried something like this?

/Teo.

Reply to
Teodor Vään

There are commercial passive antennas made (in a normal signal strength area) that feed into a building that stops the signal. Just the other day saw a powered one that a customer uses to get signal into/out of their sheet metal building.

TerryS

Reply to
Terry

Terry skrev:

It's the passive approach I'm thinking of. Thanks for letting me know that my hunch was right. I think you can do it yourself with a good Yagi (10 dB+) on one end and a good 1/2- to 1/4-wave with enough amplification to cancel out the loss in a low-loss cable. The only problem I see now is to direct the Yagi properly and get the connectors right, and depending on if I can "sell" the solution to my friend (she was doubtful if the numbers would add up properly), I might report back on the results (I think there has to be someone else on this newsgroup that has the same problem).

Thanks again,

/Teo.

Reply to
Teodor Vään

~ I just replaced my old Motorola analog flip phone (#550) with a new ~ digital phone. ~ ~ I'm disappointed in the sound quality. The analog phone had ~ reasonable sound quality and some crosstalk. The new Motorola digital ~ phone sound is "choppy", as if someone has sliced off bits of the ~ signal. (figuratively and literally). If the other party isn't ~ speaking clearly directly into his phone, it becomes garbled. There ~ is no cross talk at all, and often in the conversation I wondered if ~ we were still connected.

I think you meant to say "sidetone" (you hearing yourself talking) not "crosstalk" (you hearing sounds from OTHER calls in your channel.) I don't think crosstalk is something you would seek out.

Aaron

Reply to
Aaron Leonard

Yep, I meant to say sidetone. Crosstalk is bad, we don't want that.

Anyway, the new phone has no sidetone. However, there is a slight bit of crosstalk.

On the old analog phone, if the call was dropped, I'd know from loss of sidetone.

Reply to
hancock4

Yep, the lack of sidetone in Cellphones is definitely a step backwards and no doubt responsible for people shouting into their phones in public places. With cheap (mostly Chinese) VOIP phones also lacking sidetone it's a phenomenon that's likely to spread to the home/office. Somehow, not hearing yourself back through the receiver is even more disconcerting on a "landline".

Liam

Reply to
Telephoneman

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