Nice hack to increase signal strength

[PPCGeeks4ME]

More speculation - I am not an RF engineer, these are just my random thoughts:

I don't think these values are changing the "radio power" as we think they are. Here's why:

1. I tried setting the values to 1 and got very high signal strengths (-70dBm and higher). I then tried setting the values to 65535 and also got very high signal strengths (this time as high as -20dBm). If both ends of the scale produce high signal strengths, this could not be a linear setting of power.

2. Battery consumption does not seem to change with these values. If more power was being sent to the radio, power consumption would go up.

3. The output power of the radio is definitely unaffected by these values as that is actually decided by the tower.

After reading about CDMA in general, some things I've learned:

1. "VGA" means Variable Gain Amplifier; it's job is to take RF signals from the antenna and amplify the carrier band while discarding signals outside that band.

2. RX power measures the total amount of RF energy coming out of the VGA, inside or outside the carrier band.

3. Ec/Io is the important number; it is the ratio of carrier signal to total amount of RF energy.

I'm not sure what "offset" means in this context, but I can make an educated guess; when I change these values from their defaults, RX power goes up or down. In general, small changes seem to decrease RX power, while larges chanes seem to increase it. In both cases, Ec/Io becomes worse or at best remains the same. Therefore, I believe these values are somehow controlling the bandwidth of amplficiation by the VGA. In other words, they decide what part of the incoming signal will be kept and what will be discarded. Insane values such as 1 and 65535 probably make the window very large, hence the large signal strength.

Due to electrical differences between phones, these values are probably calibrated at the factory to focus on the carrier band.

Source for most of the above: http://www.cdmaonline.com/interactive04/flash.html

Oh, and according to the folks at XDA, a ##786# will reset these values to their defaults.

[slypher]

Originally Posted by PPCGeeks4ME

More speculation - I am not an RF engineer, these are just my random thoughts:

I don't think these values are changing the "radio power" as we think they are. Here's why:

1. I tried setting the values to 1 and got very high signal strengths (-70dBm and higher). I then tried setting the values to 65535 and also got very high signal strengths (this time as high as -20dBm). If both ends of the scale produce high signal strengths, this could not be a linear setting of power.

2. Battery consumption does not seem to change with these values. If more power was being sent to the radio, power consumption would go up.

3. The output power of the radio is definitely unaffected by these values as that is actually decided by the tower.

After reading about CDMA in general, some things I've learned:

1. "VGA" means Variable Gain Amplifier; it's job is to take RF signals from the antenna and amplify the carrier band while discarding signals outside that band.

2. RX power measures the total amount of RF energy coming out of the VGA, inside or outside the carrier band.

3. Ec/Io is the important number; it is the ratio of carrier signal to total amount of RF energy.

I'm not sure what "offset" means in this context, but I can make an educated guess; when I change these values from their defaults, RX power goes up or down. In general, small changes seem to decrease RX power, while larges chanes seem to increase it. In both cases, Ec/Io becomes worse or at best remains the same. Therefore, I believe these values are somehow controlling the bandwidth of amplficiation by the VGA. In other words, they decide what part of the incoming signal will be kept and what will be discarded. Insane values such as 1 and 65535 probably make the window very large, hence the large signal strength.

Due to electrical differences between phones, these values are probably calibrated at the factory to focus on the carrier band.

Source for most of the above: http://www.cdmaonline.com/interactive04/flash.html

Oh, and according to the folks at XDA, a ##786# will reset these values to their defaults.

Good info. Appears that we may not get much out of the tweak huh? Anyone else try?

-s

[ronaldheld]

So, are there optimal values to set, or is that phone specific?

[ShortBusCandid8]

I wrote down my default values and then halved each of the readings. That worked well for me. Rx Power went from high -90's to high -80's on both Ev & 1X by halving the default values. It now shows Ev in my livingroom consistently with 3-4 bars where it used to bounce back and forth between Ev & 1X and one bar. I can actually watch a pretty smooth SprintTV in my apartment now. Thanks to all the contributors of this thread!

[benanthony]

I agree with Slypher, I don't do CDMA either but I do run a Wireless Internet Provider company using Motorola Canopy so I look at RX and TX values everyday. It makes sense that if we widen the bandwidth by changing these numbers it will work better for some people and I would also guess that it will work better indoors than outside. Your RX signal is what the signal that your phone is receiving from the Cell tower, you don't change a radios RX power level you have what is called Receive sensitivity which is the min RX level the radio will operate. its pretty high on cell phones somewhere in the -100's.

what is probably happening is as the signal travels from the tower to your phone it is passing through objects (wall, trees, etc.) when this happens it distorts and changes the signal, so by telling the radio to use a wider bandwidth sometime you will get a better signal.

Where this is going to fail is if you find yourself in a situation where you have decent signal but end up next to another signal that your phone is now trying to use. My guess is your phone won't know what to do and drop calls and your signal strength will get very wacky.

For those who set it to a value of 1, i would be curious how your phone acts when you are around a 900Mhz coreless phone or the standing next to the microwave when its running, depending on what band your cell company is using.

[schollianmj]

well I just read through this whole thread... Im taking a chance here. I normally have a charger around, and where I work I normally only get one bar or just a bit less, just the EV or 1X with no bars but not quite searching. I just changed all 4 values to 1000. In the Debug menu the DB went from 99-102 on my desk at home to 87-90. and I show 2 bars. if I step outside where I normally show 2 bars, I now show ful bars an the DB goes to low 70's. the RX ec/io is now at 21 sitting on my desk, I forgot to check it before I changed the values, but I believe it was close to what it is now.

I will test it like this for the next three days while Im stuck at work and see how it goes.

[xconwayx]

I cut all of my defaults by 1000, all seemed well until last night where it is very difficult to receive texts. Anyone else experience this?

[schollianmj]

not yet. been running great since i did it. where I normally dont have service at work I now have 2 bars. battery life hasnt seemed to be effected either. Im liking this.

[PPCGeeks4ME]

Man, I wish we had some real info on what this does. It's strange to see that some say lowering the number a little makes things better, some say lowering the number a lot makes things better, some say raising the number a little makes things better, and some say changing the number has no effect.

[cchris81]

Originally Posted by PPCGeeks4ME

Man, I wish we had some real info on what this does. It's strange to see that some say lowering the number a little makes things better, some say lowering the number a lot makes things better, some say raising the number a little makes things better, and some say changing the number has no effect.

Exactly.

This is y i set mine back to what they were, I was one of the few that raised the numbers, I'm waiting for something a little more concrete