DSC Radios

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totopalm

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Does a DSC radio when the May Day button is activated
transmit over hundreds or thousands of miles??
Or is it like a VHF radio and governed for distance by
its aerials
 
It all works via the aerial, its NOT satellite /forums/images/graemlins/wink.gif

If you want that facility get a GPS EPIRB, plenty of previous discussions on them if you do a search, they are life savers, especially the personal ones attached to YOU, if you get thrown overboard, pointless being the GPS EPIRB being on your boat as it drifts away from you. /forums/images/graemlins/crazy.gif
 
Just wot i thought, I'll stick with Ch16 for now,
and me epirb/liferaft/lifejacket/rockets/flares
loudhailer/flags/balls/cones/upside down ensign
shouting/screaming/sobbing/vigorous waving
of arms/mobile phone/handheld gps/radio and
thats just on the Norfolk Broads!!
 
I must file a passage plan with CG, as i intend to set sail
from Brundall to Breydon Water, where according to the
Broom mob,Dragons are found!! I read once a Broom
was found wandering off Gt Yarmouth, with its deluded
grey haired skipper,tottering round deck, muttering
what time is tea served Matron??
 
[ QUOTE ]
Just wot i thought, I'll stick with Ch16 for now,
and me epirb/liferaft/lifejacket/rockets/flares
loudhailer/flags/balls/cones/upside down ensign
shouting/screaming/sobbing/vigorous waving
of arms/mobile phone/handheld gps/radio and
thats just on the Norfolk Broads!!

[/ QUOTE ]

I do that in my bath
 
DSC has much greater range that VHF and it fades like analog with distance, doesn't cut out. DSC transmits position and type of emergency to all ships in vicinity. The MMSI number is assocaited with your radio license so CG will have type of vessel etc. all instantly.
 
[ QUOTE ]
The MMSI number is assocaited with your radio license so CG will have type of vessel etc. all instantly.

[/ QUOTE ]
Thats the theory, and is nothing like the reality (is anything?) The CG has to look the vessel up in a database reknown for its lack of user friendliness.
 
So Talbot whilst the unfriendly CG are looking up my nos
I am still sinking, safe in the knowledge that noboby knows,
or maybe in my case cares.
Thank you for thought for today!!
I tell you we are all Doomed!!
 
Personally I am not a fan of DSC cause it has been designed to fit a commercial vessel requirement, and is not really suitable (IMHO) for the leisure market. If I had a DSC radio in the solent area I would always have it switched off as the alarms are a pain in the ***** Even sending out a proper IMSI message (provided you remember the correct sequence) you still need to send out a voice call. I will stick with my trusty Swiftech for as long as possible, even SWMBO can use it, and it worked perfectly on my last Mayday Relay!
 
Taken from VHF DSC Handbook by Sue Fletcher :
"Digital signals are more streamlined than voice signals and so will almost travel to the limit of the radio horizon whereas voice signals often fade away before they reach the radio horizon. Given the same set of circumstances, digital signals will travel between 10-20% further than voice"

Obviously Radio horizon depends on antenna heights, both transmitting and receiving.
 
[ QUOTE ]
Just wot i thought, I'll stick with Ch16 for now,
and me epirb/liferaft/lifejacket/rockets/flares
loudhailer/flags/balls/cones/upside down ensign
shouting/screaming/sobbing/vigorous waving
of arms/mobile phone/handheld gps/radio and
thats just on the Norfolk Broads!!

[/ QUOTE ]

Dont you have a tar barrel and box of matches just in case the others fail? /forums/images/graemlins/grin.gif
 
[ QUOTE ]
Does a DSC radio when the May Day button is activated
transmit over hundreds or thousands of miles??
Or is it like a VHF radio and governed for distance by
its aerials

[/ QUOTE ]

Seeing as you asked so nicely! /forums/images/graemlins/grin.gif

DSC or Digital Selective Calling can in fact be Tx'd over many miles if you have the right kit. I'm assuming here that you are making specific reference to VHF which will TX within the range based on both the receiving antenna as well as the originating aerial. As has been mentioned already the distance achieved via VHF DSC transmission is further than voice.

Have a look at this Link . OK, it is an Australian site but I think it explains things fairly simply yet clearly.

As I have said before, it is a paging system, your choice to have it as the there is no legal requirement for leisure vessels to be equipped with DSC sets. However the CG advice it and you will find it difficult to buy a non DSC class D set now. In fact since 1999 all class D sets have been required to DSC compatible - normally by adding a separate unit such as ICOM's DS 100 -
MainDS100SOLO.JPG


There is a danger of over complicating the issue so I'll stop at this point. You need to asses your own needs. You've got me thinking if it might be worth while running a half day update course because clearly there are many who while they may have the required Operators Certificate have simply forgotten how to use the system. Now I appreciate you are Norfolk based,so are hardly likely to travel down to the Solent, but I wonder how many others would consider such a course of value?
 
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