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dbm's explained?

So wait, is the big issue with the nexus call reception or data reception? If its call reception, im not SUPER concerned. My phone is used as a phone but I RARELY use it for anything other than shot 5 minute phone calls to work, parents, GF ect. And I text more often than not. Im more of a media hound, so data is slightly more important than perfect call reception.

How would one find the dbm's on the phone, or is it a market app specifically? I have a razr and want to have some comparisons. Im in a relatively strong 4G area where I pull between 3 and 5 bars consistently.
 
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How would one find the dbm's on the phone, or is it a market app specifically? I have a razr and want to have some comparisons. Im in a relatively strong 4G area where I pull between 3 and 5 bars consistently.

On the Rezound you'd go to the Settings menu, then About phone, then Network: look under Signal strength. It must be the same or similar on Razr.

Keep in mind that the Galaxy Nexus reports 4G/LTE signal strength dBm when connected to a 4G/LTE signal, while all non-ICS phones report the (usually much stronger) 3G/CDMA strength even when connected to 4G/LTE.
 
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Generally see better signal strength via bars and dDM on my wife's Bionic vs my Nexus. Call quality tended to be better on it (when I was using it). However, I've yet to have any issues for call quality on my Nexus. Certainly, it's not the best spec for it, but it's not horrible (as long as you're in a strong signal area).
 
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On the Rezound you'd go to the Settings menu, then About phone, then Network: look under Signal strength. It must be the same or similar on Razr.

Keep in mind that the Galaxy Nexus reports 4G/LTE signal strength dBm when connected to a 4G/LTE signal, while all non-ICS phones report the (usually much stronger) 3G/CDMA strength even when connected to 4G/LTE.

Gotcha, found it. Im pulling in -66 dbms and its INSANELY fast. From what ive heard the Nexus is pulling in between 70 and 80 in good areas, so it shouldnt be THAT big of a change, correct?

And have we figured out if its hardware or software yet? And again, is this related to data or call quality?
 
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Gotcha, found it. Im pulling in -66 dbms and its INSANELY fast. From what ive heard the Nexus is pulling in between 70 and 80 in good areas, so it shouldnt be THAT big of a change, correct?

Yeah, -66 is excellent. I typically get around -77 at home and have trouble pulling in a fast 3G signal for whatever reason.

Nexus values need to be qualified. -70 to -80 is decent for 3G, and if those are 4G then they'd be excellent since corresponding 3G signals would be roughly(?) 10-15dBm better than 4G. There are some apps that will display both 3G and 4G signal strengths, but they tend not to agree with the phone's built-in readout so I have no idea what to make of that!

And have we figured out if its hardware or software yet?

Entire 300+ post threads have been discussing that, so there's no definitive answer yet. Verizon continues to insist that there's no Nexus connection problem and that any pending fix has to do with reporting bars differently. One thing complicating the issue is that Verizon has had some atrocious network issues recently, so IMO it's very hard to isolate what's a phone problem from a Verizon problem.

Perhaps the only concrete thing one can say right now is that if you get fast and reliable connections on your phone, then it doesn't matter what dBm is reported or how many bars you have. (If your phone works great, then enjoy it and stop worrying!)
 
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Gotcha, found it. Im pulling in -66 dbms and its INSANELY fast. From what ive heard the Nexus is pulling in between 70 and 80 in good areas, so it shouldnt be THAT big of a change, correct?

And have we figured out if its hardware or software yet? And again, is this related to data or call quality?

If you are getting that strong 4G on Razr there, chances are Nexus will be just as good or even faster on 4G. Nexus would be probably -75~-85 there, but keep in mind that's 4G dBm, not 3G like Razr. I heard there is app measuring 3G, 4G dBm separately, so you may try that too.

It's only weak signal areas that data connection can be troubled (dropping 4G or taking long to switch radio) on Nexus. This is mostly for data. Nexus can do calls just fine even when signal bar is zero!
 
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So strange : all widgets and appli on my new android phone says +85 dBm !
so I have no clue to know exactly what's going on...:thinking:

Absolute lower is better? that's only for negative numbers. For very strong signal, dBm value actually becomes positive as shown in Wikipedia link above.

So in general, higher is always better, taking account of sign.;)
 
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Absolute lower is better? that's only for negative numbers. For very strong signal, dBm value actually becomes positive as shown in Wikipedia link above.

So in general, higher is always better, taking account of sign.;)

I was under the impression that dbm was a measurement of losses.
So a perfect signal (lets say you are standing on top of the Verizon Tower) would be (0). There is no such thing as positive losses, and anyone can write on Wiki, that doesn't prove anything. ;-)

I know when we periodically test our fiber-optic cables, they put a known light source on one end, and then measure the light at the other end and the result is a negative dbm value. And that value represents the loss of light over the length of the cable. I know this is apples and oranges, but I think RF signals work the same way. They are broadcasting a known RF level, and the level being recieved by your antenna on your phone minus the original level being broadcast equals your dbm loss, and it's always negative. Even a zero signal isn't really possible, only hypothetically, but a positive value is not even hypothetically possible.
 
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I was under the impression that dbm was a measurement of losses.
So a perfect signal (lets say you are standing on top of the Verizon Tower) would be (0). There is no such thing as positive losses, and anyone can write on Wiki, that doesn't prove anything. ;-)

I know when we periodically test our fiber-optic cables, they put a known light source on one end, and then measure the light at the other end and the result is a negative dbm value. And that value represents the loss of light over the length of the cable. I know this is apples and oranges, but I think RF signals work the same way. They are broadcasting a known RF level, and the level being recieved by your antenna on your phone minus the original level being broadcast equals your dbm loss, and it's always negative. Even a zero signal isn't really possible, only hypothetically, but a positive value is not even hypothetically possible.

You brought up good point. But unfortunately you are mistaken. What you are describing is pure "Decibel" (dB), which is logarithm of inverse transmission. You are correct that dB can't be positive value as it's measure of attenuation of electromagnetic power through device.

However, we are talking about "dBm" here, which is decibels in reference to one mW of power. 0 dBm means 1mW. So any power greater than 1mW means positive dBm. Read the definition/equations in above Wiki page. What matters to wireless radio device is absolute level of power received, not relative attenuation of signal power through antenna. Having good transmission through antenna doesn't necessarily mean it's getting higher EM power to radio.
 
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You brought up good point. But unfortunately you are mistaken. What you are describing is pure "Decibel" (dB), which is logarithm of inverse transmission. You are correct that dB can't be positive value as it's measure of attenuation of electromagnetic power through device.

However, we are talking about "dBm" here, which is decibels in reference to one mW of power. 0 dBm means 1mW. So any power greater than 1mW means positive dBm. Read the definition/equations in above Wiki page. What matters to wireless radio device is absolute level of power received, not relative attenuation of signal power through antenna. Having good transmission through antenna doesn't necessarily mean it's getting higher EM power to radio.

and 1.21 Gigawatts would equal....:eek:

 
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You brought up good point. But unfortunately you are mistaken. What you are describing is pure "Decibel" (dB), which is logarithm of inverse transmission. You are correct that dB can't be positive value as it's measure of attenuation of electromagnetic power through device.

However, we are talking about "dBm" here, which is decibels in reference to one mW of power. 0 dBm means 1mW. So any power greater than 1mW means positive dBm. Read the definition/equations in above Wiki page. What matters to wireless radio device is absolute level of power received, not relative attenuation of signal power through antenna. Having good transmission through antenna doesn't necessarily mean it's getting higher EM power to radio.

I stand corrected. :cool:
 
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Keep in mind..... the GN doesn't report signal strength in 1 digit increments. Its some weird list of specific values. If I recall, its like 65, 73, 83, 93, 103, 113, 120 or something similar. So its also tough to compare devices when you don't know if your 83 is actually an 88 or a 78.....

My GNex only reports odd numbers, 67,69,71 etc...

Looks like reception in the UK is pretty good! :p -51dbm

 
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Apparently, full bars of 3G on my phone is reported as -75 dbm. It it was a really strong signal too, almost 800 kbps in speedtest.

Screenshot_2012-04-08-18-15-13.png
 
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Apparently, full bars of 3G on my phone is reported as -75 dbm. It it was a really strong signal too, almost 800 kbps in speedtest.

Screenshot_2012-04-08-18-15-13.png
Only thing I would point out is signal strength and data speed need not go hand in hand. Your speed is also a function of congestion on the network and probably a host of other things as well. There are times when I have a great signal in terms of signal strength, yet 4G speeds are just "average" at 8-10 Mbps and other times with a lower signal strength data speeds are still really good, and then other times where speed and strength do track with each other.

Personally, I've never seen better than -75 dBm on my GNex. Also, the 4.0.4 update brought with it changes to the representation of bars from signal strength. Now a lower signal strength gives more bars, at least in 4G.
 
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Only thing I would point out is signal strength and data speed need not go hand in hand. Your speed is also a function of congestion on the network and probably a host of other things as well. There are times when I have a great signal in terms of signal strength, yet 4G speeds are just "average" at 8-10 Mbps and other times with a lower signal strength data speeds are still really good, and then other times where speed and strength do track with each other.

Personally, I've never seen better than -75 dBm on my GNex. Also, the 4.0.4 update brought with it changes to the representation of bars from signal strength. Now a lower signal strength gives more bars, at least in 4G.

What do you mean? Those are amazing speeds for 3G here. I normally get around 200 kbps-400 kbps. I would highly doubt it would have anything to do with congestion. The nearest town population was only 800. I know what you mean with the strength to data speed ratio, but that was nothing short of a miracle that I could achieve those speeds on 3G.
 
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lol mine at home when forced to 3G stays at -120.....and it sucks.

edit* just to add though this doesn't affect my call quality at all however. In fact i haven't dropped one call and it sounds just as clear if not more than my DX. Also my DroidX would occasionally drop calls here at home.

Mine is often at -100 to -114 at home yet I don't drop calls. also in my home is a Rezound which reflects -50 ish as I have a network extender. The Nexus dbm numbers are not boosted by the network extender.

I also had similar results as you with the DroidX. I have to say that was the worst phone I've ever had. And I've had/have a lot of phones.:cool:
 
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VZW sent out the RazrMAXX to replace my Nexus after several poor reception issues. Supposedly the Maxx has an amazing antenna in it and VZW claims there is a tower less then 1 mile from my house. So I thought I would check the dbm, went to status and was shocked to see such low numbers as I usually get -105 - -113 with the Nexus and suddenly I am seeing an -86. That was fine and great but I wanted to force the radio in to LTE only and see what we could get. So on the max I dialed ##7764726, pwd:000000, went in to test mode and locked it on to LTE only. I went back to check the signal strength and now it shows -120.

Could I have possibly been sent out a Maxx with a poor radio and antenna? Should I send it back and keep trying or do I just stick with the Nexus? For me, I am not impressed with the Maxx. I am unable to get comfortable with blur and miss the screen of the Nexus. If the signal reception was night and day I could understand. However at this point I am far happier with the Nexus. Am I nuts?
 
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VZW sent out the RazrMAXX to replace my Nexus after several poor reception issues. Supposedly the Maxx has an amazing antenna in it and VZW claims there is a tower less then 1 mile from my house. So I thought I would check the dbm, went to status and was shocked to see such low numbers as I usually get -105 - -113 with the Nexus and suddenly I am seeing an -86. That was fine and great but I wanted to force the radio in to LTE only and see what we could get. So on the max I dialed ##7764726, pwd:000000, went in to test mode and locked it on to LTE only. I went back to check the signal strength and now it shows -120.

Could I have possibly been sent out a Maxx with a poor radio and antenna? Should I send it back and keep trying or do I just stick with the Nexus? For me, I am not impressed with the Maxx. I am unable to get comfortable with blur and miss the screen of the Nexus. If the signal reception was night and day I could understand. However at this point I am far happier with the Nexus. Am I nuts?

Try getting this app:

https://play.google.com/store/apps/...251bGwsMSwyLDEsImNvbS5zZW5zb3JseS52aWV3ZXIiXQ..

As far as I know, it is the only reliable way to view both 3G and 4G signal levels on both gingerbread-based phones (which show 3G bars/dBm when in 4G) and ICS. I'd use that to do your comparisons.

Do you still have the Nexus? If so, use Sensorly with the MAXX and Nexus side by side in a few locations in your house and then you're at least comparing apples and apples. :)
 
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