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Updated Signal Check Database

Hello everyone, here’s an updated Signal Check Pro database dump covering Sprint towers.

Mostly Complete
Linn County, Johnson County

Partially Complete
Cedar County, Butler County, Muscatine County, Mercer County (IL)

Please feel free to email me with your own updates to the database, if you identify sites I’ve not yet captured, please do send me an email with the information and I will get it added to the next database update! Continue reading

RTL-SDR Based LTE Signal Analyzer

Have you ever wanted to detect what network is installed at what tower?  screenshot_01Interested to see how a network upgrade or overlay is progressing?  Or, maybe you are interested in getting a better idea of the relative signal strength of multiple LTE networks, with a passive receiver?  If so, this is the blog post for you.

This post will explain how to build a custom application for the Kali Linux system which will allow you to use a RTL-SDR DVB TV tuner chipset to perform spectrum analyzer functions on LTE signals.  Using the E4000 chipset, I have decoded LTE signals in 700MHz, 800MHz, 1900MHz (PCS) and 2300MHz (AWS) frequencies. Continue reading

Hamming it up in the Toyota Prius

With the warm weather I took a few days to fix up the ham radio install in my Prius.

Equipment:
Radio: Yeasu FT7900R 50w VHF / 40w UHF Radio
Antenna: Diamond NR770NMO (for trips) and/or Comet SS-460NMO (for urban)
Mount: Diamond K412CNMO

Hatch Antenna Mount

Hatch Antenna Mount

The Prius is a fairly straightforward car to install a radio in.  Obviously as a hatch back, a special hatch antenna mount must be purchased.  I opted for the K412 from Diamond as it adjustable on 3 axis, so I was certain I could get the antenna exactly vertical. The manual suggests this mount is good for antennas up to 42″ in height.  The mount attaches to the car by the use of two “set” screws.  Make sure to read the instructions for the antennas you are using.  If your antenna requires a ground plane, make sure that the set screws make it through the paint and are touching the metal of the car chassis itself to form an electrical connection to ground. Continue reading

Cell Phone Network Analysis With the Nexus 5

The Nexus 5 may have been discontinued by Google but the phone still packs a powerful punch for those interested in analyzing the cell network they are connected to.  This blog post is the first in a series of posts explaining how to better understand the cellular network.

Screenshot_2015-04-30-13-31-46To properly review the network information, you will need to purchase the app Signal Check Pro.  The pro version contains many logging features, which will make exploring the network much easier.

Signal Check Pro, when launched, will display information such as what is displayed on the left.  Depending on the network you are connected to, you may see various different pieces of data.  In this example, I am connected to the Sprint LTE network, running on Band 25 (1900MHz)

The signal strength bar graph at the top is self explanatory, and the RSRP and RSRQ are signal strength indicators.  Each panel (or directional antenna) will have a unique GCI to identify the panel, however Sprint conventionally assigns all panels on a specific tower the same first 6 hexadecimal numbers.  For instance, in the example to the left, the Coralville water tower, all the panels will share the same beginning GCI of 08A067xx.  Each panel will have a PCI ID as well, but these may not be unique with some PCIs being repeated.  The TAC represents a regional code shared among all sites within a geographic area. Continue reading