CSL Signal Analyser 2 – 4G Signal Tester

CSL Signal Analyser 2

The CSL Signal Analyser 2 is a handheld cellular signal tester that surveys 2G and 4G networks to find the strongest signal before you install a router, alarm, or IoT device. It runs without a SIM, pairs with a companion app over Bluetooth, and exports PDF survey reports on site. Use it to check every mobile network at a location, compare bands, and choose the mounting position that gives the most reliable connection. Note that it measures 2G and 4G only, not 5G, so treat it as a coverage-survey tool rather than a 5G meter.

Key features

• 2G and 4G survey: Measures live signal strength across 2G/GSM and 4G/LTE networks.
• No SIM required: Runs network scans with no SIM card fitted.
• Single and multi-network modes: Test one network or compare several at once from a single device.
• Live analytic mode: Plots signal over time so you can pinpoint the best installation spot.
• PDF reporting: Exports a shareable survey report after a minimum four-minute monitoring run.
• App paired over Bluetooth: Connects to a companion mobile app that also handles firmware updates.
• External aerial support: Connects to an existing aerial through the MMCX port, with an MMCX to SMA adaptor supplied.
• Wide LTE band coverage: Supports LTE bands 1, 3, 5, 7, 8, 20, 28 and more across common UK and EU frequencies.
• Rechargeable and portable: USB-C charged, 73 g, 150 mm x 74 mm x 18 mm.
• Multilingual: App available in 11 languages.

What is the CSL Signal Analyser 2 used for?

Pre-install site surveys for cellular routers

Before mounting a Teltonika 4G router or Proroute router, survey the location to confirm which networks and bands are usable. The report shows signal strength per network, so you fit the router and antenna where the connection is strongest rather than where it is convenient.

Alarm and fire signalling installations

Security and fire installers use it to verify coverage for alarm signalling devices before commissioning. Confirming signal at the panel location reduces failed transmissions and repeat site visits.

Antenna placement and cable runs

Compare signal at several candidate mounting points to decide where an external antenna should sit. This matters most in metal cabinets and plant rooms, where signal can change over a short distance. Once surveyed, choose from our 4G antennas range.

Remote and rural telemetry sites

At low-coverage sites, check every available network to find the one that holds up. The tool suits telemetry, sensor, and utility monitoring installs where a marginal signal causes ongoing dropouts.

Multi-network coverage checks

Because it scans multiple networks without a SIM, it shows which operator gives the best coverage at a site. That informs the SIM or roaming choice before a router is deployed.

Pro tip

Run the analyser in the exact position and orientation the router antenna will sit, not just roughly nearby. Signal can change by several dB across a short distance inside a cabinet or against a wall. Let it monitor for at least four minutes so the app has enough data to build a proper report, then save the PDF against the job. If you plan to use an external aerial, connect it through the MMCX port and enable the external aerial toggle in settings before you survey, so the reading matches the installed setup.

Frequently asked questions

Does the CSL Signal Analyser 2 measure 5G?

No. It measures 2G and 4G only. For a 5G deployment, use it to confirm 4G fallback coverage at the site, then verify 5G separately. If you are still specifying hardware, see our guide on choosing a Teltonika router.

Do I need a SIM card to use it?

No. The Signal Analyser 2 scans networks with no SIM fitted, so you can survey a site before you have chosen a network or ordered connectivity.

What connector does it use for an external antenna?

The aerial port is MMCX. An MMCX to SMA adaptor is supplied, so you can connect to most standard 4G antennas. Browse compatible options in our 4G antennas range.

How does it connect to the app?

The device pairs with the companion app over Bluetooth. Turn Bluetooth on before pairing. The app also delivers firmware updates and stores your saved reports.

Can I get a report from a survey?

Yes. After at least four minutes of monitoring in single network, multi-network, or analytic mode, the app generates a PDF report you can share and file against the job.

How is this different from a router with a signal readout?

This is a dedicated survey tool, not a router. It has no SIM and does not carry data. Use it to plan an install, then deploy a cellular router such as a Teltonika 4G router for the live connection.

Related products and further reading

Pair the Signal Analyser 2 with a Teltonika 4G router and a suitable 4G antenna once your survey is done. See the full 4G signal analyser range for alternatives, and read our guide to choosing a Teltonika router if you are still specifying hardware.

Example Report Summary Page