GMDSS Radio Survey Blog


Recent article

Evolution of MF/HF/VHF GMDSS Testers

Category: GMDSS Radio

The MF/HF/VHF radio stations with DSC (Digital Selective Calling) are an essential component of modern communication systems operating within the GMDSS.

DSC is used for initial calling of ship and shore stations for the purpose of further communication by radiotelephone or radiotelex. This system involves the transmission of short formalized messages, represented in encoded form using binary characters in the MF, HF and VHF bands.

The International Maritime Organization (IMO) requires all GMDSS equipment be regularly tested and maintained. Therefore, the inspection of the MF/HF/VHF radio stations is mandatory. 

Each type of such equipment must meet the requirements of SOLAS, as well as the relevant technical demands and standards. They are developed by recognized international organizations such as IMO, ITU-R. 



Marine communication has long history and continues developing to this day. For the last years this field have been changed and innovated greatly. 

At the first stages of its evolution semaphores and flags were used, later mariners began using radio for transmitting distress ...



The NAVTEX system provides the automatic dissemination of local Maritime Safety Information (MSI) by Narrow Band Direct Printing (NBDP) operating in the Forward Error Correction (FEC) broadcast mode (see Section 0 for more details on FEC operation). Depending on the geographical features of its ...


Subscribe to be updated with the most interesting news and articles on GMDSS radio survey once a month


Portable two way VHF radiotelephone equipment is used for communications between survival craft and rescue vessels. It may also be used for onboard communications on channels 15 and 17. Newer models automatically reduce the power to 1 W when these channels are selected. The equipment typically ...


Password Recovery
* By submitting the data, you agree ✓ to our privacy policy
* By submitting the data, you agree ✓ to our privacy policy