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Old 29-03-2015, 19:26   #1
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Please help me test DSC calling with the SSB

Hello everyone

I am in the US East Coast (Maryland)and just finished the whole setup for DSC calling with the Icom IC-M802.

Can anyone please call me to check if the thing works? I will be monitoring 2177, 4219.5, 6331, 8436.5, 12657 and 16903 for the next couple of hours. My MMSI is 367566560 (s/v Live Wide).

I tried USCG test call (003669999) on 4207.5 at various times of the day but had no luck. I wonder what is happening because I have no problem checking into various ham nets..

Thanks

Charlie
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Old 31-03-2015, 12:54   #2
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Re: Please help me test DSC calling with the SSB

Charlie,
1) First off, before you do anything else, please watch these videos and read this thread....
It WILL help you out a LOT!!

https://www.youtube.com/playlist?lis...ga2zYuPozhUXZX


New HF-DSC Explanation and LIVE Demonstration Videos
(I wanted this thread to be a sticky, and placed up top, so that everyone can find it....but the mods haven't gotten around to making it a "sticky" yet...)


DSC DISTRESS



2) Secondly, you CAN test your HF-DSC system with any station / vessel, anytime you desire, using one of the six intn'l GMDSS DSC freqs, that applies to the time-of-day and range/distance of communications....but, they might not have the time/inclination to respond to you....which is why some stations have automated test/reply systems...

So, if you desire to use the automated test/reply system set-up just for testing HF-DSC signaling, you'll need to use the freqs that those stations are set-up for and the time-of-day that you'll be within range of them on those freqs...

So, for example if you desire to use the USCG's automated DSC test/reply system, which they have elected to install for only 4207.5khz at only NMN, NMG, and NMC (Virginia, New Orleans, and Pt. Reyes, respectively), then you'll need to be within 4mhz range of one of those 3 stations at the time you want to test, or rather do your test during the times that you're within 4mhz range of one of those stations...

While you can do tests 24/7 with the USCG (there in VA, or New Orleans, or Pt. Reyes, CA), unfortunately only on 4207.5khz ('cause that's all their system is set-up for)....assuming you're within 100 - 200 miles of the USCG's NMN receivers (near Chesapeake VA), your best bet propagation wise, for actual on-air testing with them, is going to be mornings or afternoons on 4207.5khz...
But, be aware that your on-board noise level (both natural atmospheric and man-made RFI) is probably going to be rather high on 4mhz, especially at the dock!!
So, you may find early evening to be your best bet, overall!
{If you watch the videos above, you'll see that being in S. FL, I needed to wait until about 4 hours after sunset to make 4mhz DSC contact with the USCG (600 - 800 miles from me), just for me to show the "USCG Test" on my videos!!}


But, since public coast station WLO, uses the 8mhz and 12mhz GMDSS DSC Freqs (8414.5khz and 12577khz), as their DSC watchkeeping freqs, AND WLO is set-up to automatically reply to Routine TEST calls (not "safety" calls or "safety test" calls, as their website reads), so you can use WLO as your DSC testing station, if you desire...
Depending on exactly where in Maryland you are, you're about 850-950 miles from WLO....and that means that 12mhz is going to good during the day, and 8mhz at night....
(specifically, 12mhz will be good from approx. 1300z thru 0100z, with less noise / better signals usually nearer to the early mornings or early evenings.....and 8mhz will be usable from approx. 2200z thru 1300z....)



The EXACT procedures for both of the above (USCG and WLO) DSC Test calls (and "Safety" calls, as well) are outlined in the above referenced videos, as well as LIVE, REAL DEMONSTRATIONS, of the exact calls...showing precisely how-to do them, and the results / replies, etc...
Watch the videos!!




3) Next here are some specifics for you, in red...
Quote:
Originally Posted by svlamorocha View Post
I am in the US East Coast (Maryland)and just finished the whole setup for DSC calling with the Icom IC-M802.
Sorry to blow my own horn here, but if you haven't watched the videos yet, 'ya haven't "finished" the whole set-up...

Seriously, watch the videos referenced above, and read over the threads as well...
It WILL be of great help to you!!



Can anyone please call me to check if the thing works? I will be monitoring 2177, 4219.5, 6331, 8436.5, 12657 and 16903 for the next couple of hours.
NOBODY is using those freqs, and unless you had specifically reprogramed another radio in reverse duplex, and were using that radio for the other station, you're not going to get any response to any calls on those freqs....(note that 2177 is simplex, but the others you write are the rec freq of a duplex pair)

Your M-802 (like all M-802's) is ALWAYS monitoring 2187.5khz, 4207.5khz, 6312khz, 8414.5khz, 12577khz, and 16804.5khz DSC, ALL THE TIME the radio is powered On!!

These are the six international GMDSS DSC freqs, and the M-802 has a built-in, dedicated, DSC receiver that operates in the background ALL THE TIME, scanning all six of these freqs, using your separate DSC Receive antenna (you do have one of those, yes??)...

This has NOTHING at all to do with the "DSC Watch Mode" (which was designed into the radio almost 15 years ago, when Icom, etc. assumed that HF-DSC would be used for regular/routine and especially "public correspondence" signaling between many ships at sea, and public coast stations....but low-cost sat comm gear curtailed 80-90% of that, so for all practical purposes the "DSC Watch Mode" is useless as it comes out of the box....although you CAN easily reprogram it to be more useful, such as using DSC simplex freqs adjacent to the GMDSS DSC freqs....unfortunately that has not caught on...so, for the time being, you can just ignore the freqs that you wrote about as well as the "DSC Watch Mode" altogether...)



My MMSI is 367566560 (s/v Live Wide).
Although by the time I get on-board my boat in S. FL. this weekend, I'm sure you'll have this all worked out and working (Watch the videos and heed my advice/recommendations above), I'd be glad to help you out around Easter...


I tried USCG test call (003669999) on 4207.5 at various times of the day but had no luck.
Again assuming you're within 100 - 150 miles of them, you should have good luck in mornings or afternoons, early mornings or late afternoon is better for propagation....but remember your noise level may be quite high!!

If you have tried the test, as I show in the videos, on 4207.5khz, and you don't have too high of a noise level, you should have had success....so, if not, then I need to inquire on what you are using for a DSC receive antenna???
And, what is you regular SSB noise level like, on 4146khz (4A)??


I wonder what is happening because I have no problem checking into various ham nets..
Hard to say for sure with the limited info I have....but my guess is that it is combination of factors...

In no particular order...
a) Poor DSC receive antenna...
b) Not actually sending a DSC call out on 4207.5khz (see item "e")...
c) High 4mhz noise level (especially at the dock)...
d) Improper time-of-day for 4mhz, at that range...
e) Operator infamiliarity with the M-802 and HF-DSC signaling...

Thanks
Charlie

Charlie, I do hope this helps....
But, before you do anything else please watch these videos!!

https://www.youtube.com/playlist?lis...ga2zYuPozhUXZX

https://www.youtube.com/playlist?lis...rC-8QKVyMb4tVr

https://www.youtube.com/playlist?lis...zdjTJjHlChruyY

https://www.youtube.com/playlist?lis...ZDo_Jk3NB_Bt1y


And, read these threads...

New HF-DSC Explanation and LIVE Demonstration Videos

Icom M-802 Instr Videos(basic-adv) & LIVE DSC-Distress Call

Marine SSB Stuff (how-to better use / proeprly-install SSB, & troubleshoot RFI, etc.)




Fair winds...
John
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Old 31-03-2015, 15:15   #3
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Re: Please help me test DSC calling with the SSB

Quote:
Originally Posted by ka4wja View Post
But, since public coast station WLO, uses the 8mhz and 12mhz GMDSS DSC Freqs (8414.5khz and 12577khz), as their DSC watchkeeping freqs, AND WLO is set-up to automatically reply to Routine TEST calls (not "safety" calls or "safety test" calls, as their website reads), so you can use WLO as your DSC testing station, if you desire...
Depending on exactly where in Maryland you are, you're about 850-950 miles from WLO....and that means that 12mhz is going to good during the day, and 8mhz at night....
(specifically, 12mhz will be good from approx. 1300z thru 0100z, with less noise / better signals usually nearer to the early mornings or early evenings.....and 8mhz will be usable from approx. 2200z thru 1300z....)
Thanks for taking the time for all this. I have no problem getting an automated acknowledgement from WLO in 8MHz and 12Mhz at various times of the day when propagation between here and there is OK.
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Old 31-03-2015, 15:26   #4
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Re: Please help me test DSC calling with the SSB

Charlie,
You're very welcome.
And, since you've been able to connect with WLO on 8mhz and 12mhz, things seem okay...BUT...
But, there are 3 short points I'd like to make...
Quote:
Originally Posted by svlamorocha View Post
Thanks for taking the time for all this. I have no problem getting an automated acknowledgement from WLO in 8MHz and 12Mhz at various times of the day when propagation between here and there is OK.
I'd like to politely suggest:
a) that you watch the whole video playlist for HF-DSC Comms, as well as for the M-802 specific instructions....
https://www.youtube.com/playlist?lis...ga2zYuPozhUXZX

https://www.youtube.com/playlist?lis...rC-8QKVyMb4tVr

(yes, that will take you an hour or so...but I tried to make the videos understandable to all, including novices/laypersons, but have also heard from fellow radio nuts like myself w/ 40+ years of experience that have also learned something from the videos...heck it's FREE, so why not!)

b) after you watch the videos, try a test call to the USCG on 4207.5khz...

c) report back here, details on your set-up...particularly what you are using for a DSC receive antenna, and what your 4mhz noise level is...

Please do these 3 things before you conclude that everything is 100% regarding your HF-DSC set-up...



And, you may also find the offshore weather series useful as well...

https://www.youtube.com/playlist?lis...zdjTJjHlChruyY



Fair winds..

John
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Old 31-03-2015, 15:27   #5
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Re: Please help me test DSC calling with the SSB

Quote:
Originally Posted by ka4wja View Post
NOBODY is using those freqs, and unless you had specifically reprogramed another radio in reverse duplex, and were using that radio for the other station, you're not going to get any response to any calls on those freqs....(note that 2177 is simplex, but the others you write are the rec freq of a duplex pair)

Your M-802 (like all M-802's) is ALWAYS monitoring 2187.5khz, 4207.5khz, 6312khz, 8414.5khz, 12577khz, and 16804.5khz DSC, ALL THE TIME the radio is powered On!!

These are the six international GMDSS DSC freqs, and the M-802 has a built-in, dedicated, DSC receiver that operates in the background ALL THE TIME, scanning all six of these freqs, using your separate DSC Receive antenna (you do have one of those, yes??)...

This has NOTHING at all to do with the "DSC Watch Mode" (which was designed into the radio almost 15 years ago, when Icom, etc. assumed that HF-DSC would be used for regular/routine and especially "public correspondence" signaling between many ships at sea, and public coast stations....but low-cost sat comm gear curtailed 80-90% of that, so for all practical purposes the "DSC Watch Mode" is useless as it comes out of the box....although you CAN easily reprogram it to be more useful, such as using DSC simplex freqs adjacent to the GMDSS DSC freqs....unfortunately that has not caught on...so, for the time being, you can just ignore the freqs that you wrote about as well as the "DSC Watch Mode" altogether...)
Thanks for pointing out the nonsense in the "DSC Watch Mode". I heard about that several years ago and thought it had been fixed. It is a pity it has not caught up, I understand it is bit messy to do from the control panel but I have already entered the "revised" simplex frequencies that I think come from you and (using the Icom software, the CI-V cable and a little adapter to make it an OPC-478) I can clone them to other boat that we may want to be in HF contact with...

I will be back on this boat in late April and will get in contact with you to test a routine DSC call, which is what I really wanted to try before I start cloning other people´s radios with the same setup.

Thanks again

Charlie
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Old 31-03-2015, 15:43   #6
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Re: Please help me test DSC calling with the SSB

[QUOTE=ka4wja;1789967]Charlie,
You're very welcome.
And, since you've been able to connect with WLO on 8mhz and 12mhz, things seem okay...BUT...
But, there are 3 short points I'd like to make...
I'd like to politely suggest:
a) that you watch the whole video playlist for HF-DSC Comms, as well as for the M-802 specific instructions....
https://www.youtube.com/playlist?lis...ga2zYuPozhUXZX

https://www.youtube.com/playlist?lis...rC-8QKVyMb4tVr

(yes, that will take you an hour or so...but I tried to make the videos understandable to all, including novices/laypersons, but have also heard from fellow radio nuts like myself w/ 40+ years of experience that have also learned something from the videos...heck it's FREE, so why not!)

b) after you watch the videos, try a test call to the USCG on 4207.5khz...

c) report back here, details on your set-up...particularly what you are using for a DSC receive antenna, and what your 4mhz noise level is...

Please do these 3 things before you conclude that everything is 100% regarding your HF-DSC set-up...
/QUOTE]

The setup is:
  1. IC-M802 with AT-140 tuner and 23-ft Shakespeare whip.
  2. Radio connected to tuner with fat 50-ohm coax
  3. Dynaplate connected to tuner with 4ft of 3-in copper tape.
  4. Tuner directly below whip and connected via 2 feet of GTO cable.
  5. Radio ground terminal not connected to anything. Shield of tuner control cable is connected to tuner ground terminal (and Dnaplate via tape).
  6. Radio ground terminal is not connected to anything.
  7. DERA receive antenna is a Metz WEFAXDSC mounted on the stern arch and connected to the radio by 35ft of RG8X. I do not know of a way to test the antenna when plugged into the right spot, but I tested it receiving various Weatherfax frequencies when plugging it into the "normal" antenna connector.


So far so good. Only goofy detail I see is that the whip is very close to a stainless arch/davit structure and when I send out 120 or 130W (say whistling in phone mode) out in 40 meters I push lots of RF into the DC wiring. Tried a few of the usual tricks from the home shack but the only thing that has worked is shifting the antenna away from the arch or replacing it with a wire from tuner to close to the masthead (just for test, cannot do that underway because of roach). I do not see how this issue may affect my 4Mhz USCG DSC acknowledgement issue, hence I want to try DSC calls in various bands to narrow down the problem, whcih may be related to 4MHz or to something specific to the USCG stations..

I will appreciate any insight.






I do not see how this
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