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Bruce in Alaska
 
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In article .net,
"Doug" wrote:

"Bruce in Alaska" wrote in message
...
In article ,
Wayne.B wrote:

Actually not. My question was, "How can I ensure that my DSC radio is
actually hooked up and working, i.e, is the position information and
identifier being sent correctly?"

The licensing information and issuance of an identifier is an entirely
different topic.


If you knew someone with a ROSS DSC Vhf from a few years back, it will
display the data transmitted from a DSC Radio. This could be done with
the test radio on a "Dummy Load" so as to not radiate a False Distress
Signal. Or, just about any full GMDSS Suite could display the data
transmitted.

Bruce in alaska
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add a 2 before @


I spent a lot of time about a year ago calling the various technical support
people at Standard Horizon, ICOM, SEA, etc., about proper service shop
testing of DSC. What I found out was the "factory" service guys use two
radios, dummy loaded, to talk to each other, just as an on the air chat
between two DSC radios would do. The Distress function may not be done dummy
loaded only. The USCG has issued direction that a shield room or shield box
be used in addition to the dummy load for the recreational type radios.
Remember, dummy loads are not perfect and plastic box radios do radiate
also. The bottom line...there is not proper way for a recreational boat
owner to test the Distress button function, other than built in self test
non-radiating functions some radios have built in. The DSC function itself
can be tested by talking to another DSC, MMSI registered station. The GPS
location shows on the display of modern DSC radio. The GPS location received
from another vessel can be shown on a chart plotter that have the NMEA
OUTPUT from the DSC radio connected to a plotter input (only top of the line
recreational radios have that feature).
I have no actual experience with the $25K full GMDSS test sets used on the
commercial high seas equipment.
73
Doug K7ABX



Very good post Doug....

I would add, that part of the SOLAS Inspoection of any GMDSS Suite is
the testing of the Distree Signal Transmitter RF Output Data Stream
to prove that the required data is correct and encoded correctly.
this happens into a Dummy Load, and NOT during Silent Periods.

Bruce in alaska
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add a 2 before @