RE:
previous Thunderbolt had better 3G connection than your current Razr M.
From various postings I have read by other users, this may be typical. Possibly related to the smaller profile of the Razr M, and the fact that there are MORE antenna duties in the smaller package (Razr M runs all the antenna and radio requirements of larger Thunderbolt - plus - also has both 2.4GHz AND 5GHz WiFi antennas in smaller package - almost forgot they also put in a NFC Radio & Antenna too). The other day I was thinking/wondering if the location of the NFC antenna (on the back-side so hip-people can bump-transfer between devices ... to the awe-amazement of their iPhone brethren) is possibly obscuring the 4G/3G antenna reception. If so, and user does not care about NFC (me for one), then possibly the NFC antenna could simple be removed from the device & NFC software left de-activated. I know other Razr now also come with NFC antenna, but in larger package with more room to effectively place all the various antenna more optimally ...
RE:
prl 15154
I would not be attempting to switch this PRL (your references related to
"Tried #22899 or was it *22899" and/or possibly *228. If this were to actually take hold, I believe it would change your PRL to a 5xxxx number that would effectively set the phone to 3G mode and NO 4G (for folks who are in fringe areas of 4G coverage, and/or those who do not want the always on battery drain of 4G - on unless airplane mode).
RE:
"I didn't know you could update your prl on a 4g phone."
It is my understanding that you can update 4G PRL (typically it's automated process when the phone boots, but there is manual update procedure if this is the problem).
I do not think this is issue on your device because of the PRL you mention.
Exception (previously mentioned in eariler post - if you can not get 4G in area of known strong 4G coverage, check the PRL to see if the phone may have "auto-updated" to a 5xxxx PRL). This could indicate a trouble spot to focus some attention trouble-shooting. This be be one of those device that you may want to focus on PRL updating.
RE:
"It goes from 4g to 3g at -116dbm."
Device switches to and from 4G at -116dbm?
I watched signal strength on my Razr today in areas of good to moderate 4G converage (ranged from -82dbm to -108dbm with no switching out of 4g).
As I sit here typing in location I do not typically get 4G & is typically very weak 3G I've got 4G.
Moving around and obscuring device from cel-tower in various ways I got the following readings:
4G -107-115dbm 2-bars & -116-128dbm = 1-bar
Actually got device down to -133dbm with 1-bar before switched from 4G to 3G then also lost 3G into 1x.
Device would not register 3G or 4G (somewhat typical performance because coverage is very weak here).
Switched device into "airplane mode" (turning off data radios), and switched back on, and 4G signal pops up at -110dbm (same as it was in same location earlier).
In my mind this seems like explainable and acceptable behavior to me.
RE:
"Is it safe to switch it to a higher decible and what is the threshold for the thunderbolt?"
Switching threshold for the Thunderbolt is a good question. Maybe someone with active Thunderbolt could respond (my daughter will not be home from college again till next month, I will try and remember to check her Thunderbolt then).
I think the real question here is does the Razr M actually not receive signal as strongly (as say the Thunderbolt), or is it a matter of how the device signal is calibrated in the software. If the problem is that the device does not pick up signals as well, then focus probably should be on hardware improvements and/or software that can "enhance" the signal strength in the device. If on the other hand, the problem is that the signal is picked up ok but that the software calibration is set so as to switch from 3G to 4G prematurely then it would seem a simple registry edit to effectively change the switching threshold might be in order. Reasons the threshold may be set artificially low could include like to save battery, or make sure that the transition back and forth is seamless without dropping data connection. Considering the Razr M is a new device (and that packing in the secondary WiFi 5GHz radio & antenna - significant reason for my purchase of Razr M), I would think Motorola would error on the side of making sure the switching between 3G & 4G happens without dropping data signal for a fraction of second (so hopefully on the conservative side, and maybe room for future improvement via simple software update ...).
RE:
"Coverage map for my area http://www.verizonwireless.com/b2c/C...IRTON&state=WV
Even in areas that are dark red I am lucky I get 4g."
You are reading that map to show 3-levels of red (3G, 4G Extended, 4G Coverage), correct (not just 2-levels of red)?
When I zoom in your push-pin, it's in 4G Extended and near border of 3G.
It took me a little bit of time to asses the zoom levels in my area map coverage, and to see detail that actually illustrated detail down to 4G outdoors vs. inside buildings. The map where I am is fairly consistent with the coverage I experience in with my primary Razr M.
I am not advocating that the Razr M has superior 4G Data coverage. I did not select this device for 4G. My priorites - dual-band WiFi and the small form factor, along with 4.3" screen that looks great and exterior support for SD-Card were all high on my priority list. Oh, lets not forget somewhat minimal overlay onto the OS.
Hopefully, some of this makes sense and can be of help to you trouble shooting perceived and/or real problems (and differentiating between).
Regards,