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Cross Country Wireless Sentinel HF SDR Noise Measurement receiver and program

Product discontinued, web page for information only

The RSGB noise measurement project finished on 31 October 2017.

A new version of the Sentinel SDR program without the RSGB noise measurement reporting routine can be downloaded here.

CCW Sentinel HF SDR receiver

CCW Sentinel HF SDR receiver

CCW Sentinel HF SDR noise measurement program screenshot


CCW Sentinel HF SDR noise measurement program screenshot


The Sentinel 2 SDR receiver is now available as an alternative to the original Sentinel receiver.

We no longer manufacture the original Sentinel SDR noise measurement receiver and SDR program. The receiver was designed to accurately measure the HF noise floor and send telemetry reports by APRS.

The Sentinel receiver and program also works well as a general purpose SDR receiver covering 2 to 15 MHz.
The MMVARI digimode program is built into the Sentinel SDR program to allow decoding of PSK, QPSK, RTTY and GMSK HF data modes using the PC internal sound card.

Recent telemetry reports from a prototype receiver can be viewed here. Results after 6 January use the current software and frequency list.

The software scans five HF frequencies and provides the peak, median and minimum levels of 500 measurements per frequency every 10 minutes. The receiver bandwidth is 500 Hz.

The five frequencies used are:

3.499 MHz just below the 80m amateur band
5.258 MHz just below the 60m amateur allocation
6.999 MHz just below the 40m amateur band
10.090 MHz an unused frequency in the aeronautical mobile allocation
13.400 MHz in the radio astronomy allocation

As the receiver uses a built-in sound card the calibration is independent of the PC used and it will be supplied with calibration information traceble back to National Standards. This will allow the RF level and frequency measurements to be calibrated to a professional standard.

The program uses serial port control of the DDS synthesiser. The program runs on Windows 2000 or Windows XP with a low CPU load so that older PCs and laptops can be used.

A final version of the Sentinel SDR program can be downloaded here.

A FAQ sheet for the Sentinel receiver can be downloaded here.

This development ties in with the Noise Measuring Campaign recently launched by Gwyn Williams, G4FKH of the RSGB Propagation Studies Committee. The Noise Measuring Campaign records HF noise levels regularly recorded by many participating radio amateurs.
This development will add a number of calibrated noise measuring receivers to provide additional information to the project.
More information on the Noise Measuring Campaign is available here.

The latest patch for Microsoft XP for the "WannaCrypt" malware can be downloaded here.

Contact Chris Moulding, G4HYG via Email address hidden from spambots for more details.

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