Same here, on the other coast, but with the additional text, "Announcement for switch [digit] [digit] [digit] dash [digit]."
(Actual digits redacted to "[digit]" for privacy's sake.) Cheers, -- tlvp
-- Avant de repondre, jeter la poubelle, SVP.
yet you still claim it can't be done??
nonsense.
i don't know about 'nobody else' but it's clear as hell that i know way the f*ck more than you do.
Good question. I guess it's because I've seen so much made-up stuff from the likes of nospam, that you're one of the few people here we can trust.
T-mobile gives out a signal booster where you put on unit in the window and another unit in the middle of the house.
It's supposed to "boost" the signal.
I think this is the case that the signal booster passes through the original tower ID since I don't see any *new* tower ids when I hook up the signal booster. Of course, it could just be that the signal booster isn't working because the signal strength doesn't get any better either.
I do have a femtocell also, and that *does* have its own unique ID which I have identified already.
So the question was just about whether the booster generates its own unique cell id or if it just passes through the cell ID of a tower somewhere in Santa Cruz or San Jose.
Thanks. That made sense. By the way, long ago you helped me set up a Linksys WRT54G as a wired extender (yes, you cautioned against it in favor of better solutions).
Do you think it makes a difference if I hook up the femtocell to the wired extender versus the main router?
The nearest tower is only a couple of miles away, but consistently I get connected to towers that are ten and fifteen miles away. They bounce around as I watch them from the MIT CellTracker app.
Without the booster and without the femtocell, I get horrid signal, roughly minus 90 to minus 105 decibels. With the femtocell, I get minus 60 decibels consistently. I can even have stronger cellular signal strength than wifi signal strength, which is amazing.
And, yes, *all* my neighbors have either a booster or a femtocell or they use WiFi calling (since bad signal is ubiquitous in these hills).
Thanks for showing me how to do the math to approximate the distance to the antenna based on the received signal strength indication.
I must not have stated clearly which is that the only time I get minus sixty decibels is when the femtotower is in place, where it's only a few feet from my phone.
Otherwise, I get around minus a hundred decibels, which sucks.
+27dBm Estimated transmit power from the cell site +10dB My guess of the panel antenna gain-100dBm Receive signal level from your test.
Path loss = 27 + 10 + 100 = 137dB At 700MHz: Puts the antenna at about 2 miles away.
There *are* antennas two miles away (and sometimes I connect to them); so the math isn't as bad as I thought. I also connect to antennas ten and fifteen miles away, but that's driving distance, so I'd have to look at the distance as the crow flies, which could be in the less-than-five-mile range.
I tried it again and got the same thing as you ending in "Announcement for switch 40-6". 40 is the SID (system identifier) for the San Francisco Bay area: The 6 is the NID (network identifier). These numbers also agree with the local VZW tower data as displayed by the NetMonitor app. The phone is NOT activated and therefore shows everything as roaming. Operator: 310 00 (Roaming) Type: CDMA - EvDo Rev A Carrier: Verizon Wireless SID: 40 NID: 6 BID: 4864 Signal: -88dBm
I have some better phones (Samsung S4(?) and S6) in my palatial office that I can try later next week.
-- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558
Well, I screwed up a little. I left out the antenna gain of your cell phone, which I assumed to be 0dB at 700MHz. That's probably optimistic and -3dB would be more reasonable. So, the calcs should be something like:
+27dBm Estimated transmit power from the cell site +10dB My guess of the tower panel antenna gain ??dB Calculated path loss -3dB My guess of the cell phone antenna gain -53dBm Receive signal level from your test. Path loss = 27 + 10 - (-3) - (-53) = 93dB Calculating the distance where the path loss would be -93dB at 700MHz: is about 0.94 miles or about 5,000 ft. The cell tower would need to be rather close to your location or you're getting your signal from the neighbors.The +27dBm (500mw) and +10dBm antenna gain are based on my guess(tm) of the power per carrier for a real cell tower and a typical panel antenna and with some reduction in power thanks to transmit power control. Power levels and antenna gains for DAS (distributed antenna system), small cell, microcell, picocell, analog repeaters, etc are much lower. I can build you a table for the various device that will produce more accurate results.
Also look at the antenna gains on both ends, any RF obstructions including Fresnel zone blocking, and the accuracy of the signal level meter in the cell phone. Remember, in RF real RF power, sensitivity, antenna gains, and path loss, are always worse than calculated.
I don't want to comment on the T-Mobile signal booster due to lack of experience with the device and general lack of info on what's inside. If you can supply an FCC ID number, I might be able to excavate something useful from the FCC ID data dumpster.
-- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558
Just returned from a hike in the mountains. It's freezing in the mountains today. You are sending cold winds from Santa Cruz over the ridges!
T-Mobile calls *everything* a "Personal CellSpot" so, this is a photo of my signal booster from T-Mobile:
On the back of the existing devices are these FCC IDs:
What I'm mostly interested is in figuring out how to tell if they're working, since I can't seem to get different results with or without them hooked up (and, of course, with the femtocell connected to my router turned off).
I'm guessing based on the experimental results (which could be misleading) that they just pass through the cell tower id.
Here's the company that makes it (Nextivity): Methinks that's the model. Here's the "data sheet" which amazingly is devoid of most useful numbers: It does mumble that it uses a 5GHz link between the two boxes.
That's the unit with the cellular radio end. Transmit power is about
100 mw. Doesn't appear to use wi-fi on the 5GHz band so my guess(tm) is that it simply remodulates the received 1700/1800 RF carrier onto 5GHz. You probably won't see the 5GHz line with any of the Android wi-fi tools, such as WiFi Analyzer.I'll look some more after I haul some firewood up the hill, clean off the roof (in the rain), and deal with friends bugging me about their weekend projects. Also, I'm still having problems with the new and improved FCC ID document format, which balkanizes the test results into as many seperate sections as possible in order to make them difficult to download and read.
That would also be my guess(tm). Nothing is demodulated or decoded by the unit. Simply amplified and retransmitted on 5GHz. More later.
-- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558
Here's the basic patent on the system which includes a block diagram and description showing how it works: "CDMA UNII link" That's for CDMA, but I couldn't find anything for GSM, UMTS, and WCDMA. More patents: I'll grind my way through the list later...
-- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558
On Sun, 19 Feb 2017 13:00:11 -0800, Jeff Liebermann wrote, re #878#:
Sure enough, the digits I heard indicate several VZW centers in my state.
My NID digit was "2". Technically, though I'm on the Verizon network, I'm activated on Page Plus Cellular. No idea what difference that may make.
Anyway, thanks for the SID lookup URL. Cheers, -- tlvp
-- Avant de repondre, jeter la poubelle, SVP.
UPDATE:
I know everyone loves OpenSignal but I prefer an app that provides the EXACT cellular source when, in my case, it's often a femtocell that is never going to be on ANY Internet database.
To that end, see this post today on this topic, if it helps others. o Galaxy S9 in UK - poor signal?
I agree for cellular you need to be connected to the carrier, which is a drawback - but luckily you have a second SIM card, where the apps I use can handle two SIM cards (if the phone can handle two SIM cards of course).
I wouldn't suggest OpenSignal since it's an Internet lookup database which uses triangulation (last I checked anyway) ... where I'd use one of the apps in the references that does NOT need any access to the Internet.
I just looked on my phone where I have "Cellular-Z" freeware installed, which seems to work well to show signal strength in RSSI, RSRP, RSRQ, & SINR.
In my case, I test femtocell signal and cellular repeater signals, where my femtocell would never be in an Internet database.
o Cellular-Z, by JerseyHo "Cellular Z is a telecom signal quality and Wifi network info, channel info software, the main functions are as follows:
1.Dual SIM mobile phone network information (SIM card serving cell, serving cell signal quality,neighboring cells). 2.Wifi information (connected, nearby Wifi list, Wifi channel 2.5 and 5 GHz).On 9/14/19 12:01 PM, Arlen Holder wrote: [ Nothing of any use, as always. ]
Go f*ck yourself.
-- "I am a river to my people." Jeff-1.0 WA6FWi http:foxsmercantile.com
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