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Old 25-02-2014, 19:54   #31
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I have a question about filters and the M802.

I was quite surprised to learn that this radio has very sophisticated filters for digital modes, including three filters for J2B mode, which is used for PSK31. This is something you have to pay extra for with even pretty good ham transceivers.

Yet there is no mention of any filters for any phone modes. What's up with that? Is filtering all done in DSP (how?)? Does channelization in the marine bands make it unnecessary? But then how about the amateur bands? Is this a problem for operation in the amateur bands?
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Old 26-02-2014, 03:04   #32
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Re: Icom M-802 Instr Videos(basic-adv) & LIVE DSC-Distress Call

Quote:
Originally Posted by Dockhead View Post
I have a question about filters and the M802.

I was quite surprised to learn that this radio has very sophisticated filters for digital modes, including three filters for J2B mode, which is used for PSK31. This is something you have to pay extra for with even pretty good ham transceivers.

Yet there is no mention of any filters for any phone modes. What's up with that? Is filtering all done in DSP (how?)? Does channelization in the marine bands make it unnecessary? But then how about the amateur bands? Is this a problem for operation in the amateur bands?

The tight voice spec makes filtering unnecessary, in ham land , cause you can put all sorts of junk on the line , you tend to get more filtering options

Dave
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Old 26-02-2014, 03:06   #33
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Re: Icom M-802 Instr Videos(basic-adv) & LIVE DSC-Distress Call

Quote:
Originally Posted by ka4wja View Post
Dave,
Yes, you are correct that nomenclature is important...and yes, "signaling" might not be part of the official GMDSS master plan...
But, I hope you don't mind if I defend myself a little bit here...

1) These videos are NOT designed to be a study guide for a GMDSS certificate, but rather are just what I stated up front (and in the videos themselves), they are designed to assist non-technical sailors in the operations of their Icom M-802's....
That's it....

(oh, and they are FREE....and anyone can comment on 'em, for free....and I'll try to address anyones' comments/queries....)



2) And, you do know that on this side of the Atlantic, we ignorant Americans sometimes "invent" our own language / nomenclature...


3) And, finally I was just "winging it"....speaking extemporaneously....
I had NO script, nor outline....
So, sometimes the words spewing out of my mouth, might not have been precise enough for 'ya....


Dave, thanks again for helping....and please take note of my use of smiley faces ....



Fair winds,

John
s/v Annie Laurie




P.S. One of the only comprehensive GMDSS videos I've seen on-line is from 1992!!! (and they even have the old, now defunct, INMARSAT-E beacons)....
The video is okay, but in addition to those old beacons, it has some errors / oversights....


Sure , sure . I'm always surprised at the lack of GMDSS knowledge amongst US radio users. It's one of the reasons I bemoan the lack of formal radio training. So much is misunderstood in the US about DSC , GMDSS and the interaction of all the jigsaw pieces. Wasn't helped by USCG confusion and the late arrival of Rescue 21.

Dave
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Old 26-02-2014, 15:11   #34
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Re: Icom M-802 Instr Videos(basic-adv) & LIVE DSC-Distress Call

Terry,
You're an observant guy!!
But I made a "judgment" call on this one...
Quote:
Originally Posted by TLSparks View Post
One question. When I did a similar Distress test, I was in DSC Watch when I pushed the button and it went through all 6 frequencies.
I've spent quite a bit of time over the past 10 years impressing on cruisers / M-802 owners that the M-802's dedicated DSC receiver operates in-the-background, the whole time the unit is ON, continuously monitoring the 6 int'l GMDSS DSC safety, urgency, and Distress freqs (assuming they have an antenna connected to the DSC receiver jack)....and that "DSC Watch Mode" configures the "main unit" scan 6 different DSC freqs (which for 99.99% of cruisers have no use).
So, in making the videos I thought if I was to mention the "DSC watch mode", etc. this might add confusion...

And, even here I don't wish to drift this around too much, and ad to any confusion!!

[remember that a "Simple" DSC-Distress Call is a "single-freq" DSC-Distress Call, sent out at 8414.5khz.....and a "Regular" DSC-Distress Call defaults as a "6-freq" DSC-Distress Call, or you can select any one of these 6 freqs, as well as specify a Distress "type" such as "fire", "sinking", etc.]

Further, I wanted to show that if desiring to send a "regular DSC Distress call" (a 6-freq distress call) by pressing the DSC button, then pressing "SET" button and verifying that "DITRESS" is selected and then pressing "enter" 3 times...you can also select/specify any one of the 6 freqs if desired, as well as specify the "type" of Distress....



Others may have a different opinion here on whether or not to mention the "DSC Watch Mode", but I decided to avoid any confusion and not mention it in the videos....

But, for those actually reading all of this (????), Terry's observations are correct that by just pressing "DSC" and entering the "DSC Watch Mode", and then pressing and holding the red "Distress" button for 5 seconds, you will set-off a 6-freq DSC call...

So, yes Terry, all M-802's do that...



Fair winds and thanks for being so observant!!

John
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Old 26-02-2014, 17:40   #35
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Re: Icom M-802 Instr Videos(basic-adv) & LIVE DSC-Distress Call

Dockhead,
No worries here....

Yes, the M-802 is a full IF-DSP radio...designed in tandem with the IC-756ProII....
Quote:
Originally Posted by Dockhead View Post
I have a question about filters and the M802.

I was quite surprised to learn that this radio has very sophisticated filters for digital modes, including three filters for J2B mode, which is used for PSK31. This is something you have to pay extra for with even pretty good ham transceivers.

Yet there is no mention of any filters for any phone modes. What's up with that? Is filtering all done in DSP (how?)? Does channelization in the marine bands make it unnecessary? But then how about the amateur bands? Is this a problem for operation in the amateur bands?
The M802's first IF is at 64.455mhz, and there is a first IF crystal filter (nowadays called a "roofing filter") of 15khz wide.

The M-802's second IF is at 455khz, and there is a 2nd IF ceramic filter of approx. 10khz wide.
(note that ceramin filters at 455khz perform very well, and are usually as good or better than crystal filters in the typical 9mhz or 10.7mhz range)

The M-802's third IF is at 12khz, and here is where the DSP module does all the work of mode filtering, demodulating various modes, etc.
The DSP (Digital Signal Processor) circuit enables digital IF filtering, digital noise reduction, digital PSN (Pulse Shift Network), phase demodulation, digital automatic notch, etc.
(as well as does all the "modulating" and "speech compressing" during transmission)


The M-802 is designed (both hardware and firmware) to conform to the FCC Part 80, 87, and 90 standards, and therefore there is no feature for changing any of the transmit filtering....
And, in receiving:
--- the SSB voice bandwidth is controlled at 2.4khz wide....
--- the AM voice bandwidth is 6khz (I think??)
--- the CW and FSK-Narrow(F1B) and AFSK-narrow (J2B) bandwidth is 500hz...
--- the AFSK/J2B-middle bandwidth is 1khz...
--- the FSK/F1Bwide bandwidth is 1khz...
--- the AFSK/J2B-wide bandwidth is 2.4khz...

In "e-mail mode", the filter bandwidths are:
--- narrow is 500hz...
--- middle is 2.4khz...
--- wide is 2.8khz...

And, since the IF-DSP filtering is very tight and sharp ("steep skirts") with what is referred to as "brick-wall" filter shape, the actual perceived bandwidths in operation are the best of both worlds, I.e. allowing the entire desired signal to pass thru without distortion (IMD) nor excess group delay, AND reducing/eliminating unwanted signals, just a few dozens of hz away from the filter edges...

Also, be aware that the M-802's main receiver (as opposed to the narrow-band DSC receiver) uses no RF amp in the receive chain...just like my beloved (and 35 year old) Drake TR-7's, the "front-end" of the M-802 IS the first mixer (a hi-level DBM), so and with hi-quality, low-phase noise LO's (and a good 15khz wide 1st IF filter, and 10khz 2nd IF filter), actually places the M-802 in the very top end of HF receivers on the market today (actually even better than radios selling for twice or three times the price!)...

The fact is that there are NOT "variable bandwidth" filters in the DSP module, but rather are "fixed" filters for the mode used...
And, hence it just get the blood of many "hams" flowing!!!
'cause there just ain't enough knobs and controls!!!


Bottom line:
It's a great receiver, but unless you're a software engineer and/or have access to the IC-756ProII firmware, etc, there is little you can do about the "fixed" bandwidths...

I hope this helps...

73,
John, KA4WJA
s/v Annie Laurie
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Old 26-02-2014, 19:20   #36
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Re: Icom M-802 Instr Videos(basic-adv) & LIVE DSC-Distress Call

Sorry about this...
Quote:
Originally Posted by ka4wja View Post
And, hence it just get the blood of many "hams" flowing!!!
'cause there just ain't enough knobs and controls!!!


What I meant to write was that it DOESN'T get the blood of many hams flowing...'cause there just ain't enough knobs and controls!!!

Fact is the M-802 has a GREAT receiver, which outperforms probably > 99% of the "ham" transceivers out there, including many that cost 2 - 3 times the price!!
It doesn't have phase noise issues like many modern $3000 - $5000 ham rigs have, and hence doesn't suffer from noise-limited IMD...it does not suffer from recip mixing IMD, etc.

I could go on....but fact is, it is a great radio.....just doesn't have enough knobs, buttons, and "whiz-bang" features to attract a cult following...


Surprisingly, and actually, most modern HF (ham or marine), made/sold in the past 10 years or so, have receivers that perform more than adequately for HF Voice (SSB) on the ham radio bands these days....mainly because of two reasons:
a) the occupied bandwidth of the voice/SSB signals prevent stations from operating too close in frequency to each other...
b) the truly horrible transmit IMD and wideband transmit noise produced by ham transceivers (even $3000 - $6000 ham transceivers), produces so much noise and IMD products on the air (and inside the receiver's passband), that most receiver's ultimate specs (when using wide-bandwidth modes such as SSB), are fairly moot these days!!
(Meaning that, in SSB service, these receiver's are not pushed to their ultimate maximums, due to the above reasons...)



{Note that, unlike SSB, with CW, and especially CW contesting, and other narrow-band modes, such as PSK31 contesting, etc. the ultimate receiver spec's of the high-end units (such as the M-802) actually CAN be of great use...}



Fair winds...

73,

John
s/v Annie Laurie
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Old 27-02-2014, 21:00   #37
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Quote:
Originally Posted by ka4wja
Dockhead,
No worries here....

Yes, the M-802 is a full IF-DSP radio...designed in tandem with the IC-756ProII....
The M802's first IF is at 64.455mhz, and there is a first IF crystal filter (nowadays called a "roofing filter") of 15khz wide.

The M-802's second IF is at 455khz, and there is a 2nd IF ceramic filter of approx. 10khz wide.
(note that ceramin filters at 455khz perform very well, and are usually as good or better than crystal filters in the typical 9mhz or 10.7mhz range)

The M-802's third IF is at 12khz, and here is where the DSP module does all the work of mode filtering, demodulating various modes, etc.
The DSP (Digital Signal Processor) circuit enables digital IF filtering, digital noise reduction, digital PSN (Pulse Shift Network), phase demodulation, digital automatic notch, etc.
(as well as does all the "modulating" and "speech compressing" during transmission)


The M-802 is designed (both hardware and firmware) to conform to the FCC Part 80, 87, and 90 standards, and therefore there is no feature for changing any of the transmit filtering....
And, in receiving:
--- the SSB voice bandwidth is controlled at 2.4khz wide....
--- the AM voice bandwidth is 6khz (I think??)
--- the CW and FSK-Narrow(F1B) and AFSK-narrow (J2B) bandwidth is 500hz...
--- the AFSK/J2B-middle bandwidth is 1khz...
--- the FSK/F1Bwide bandwidth is 1khz...
--- the AFSK/J2B-wide bandwidth is 2.4khz...

In "e-mail mode", the filter bandwidths are:
--- narrow is 500hz...
--- middle is 2.4khz...
--- wide is 2.8khz...

And, since the IF-DSP filtering is very tight and sharp ("steep skirts") with what is referred to as "brick-wall" filter shape, the actual perceived bandwidths in operation are the best of both worlds, I.e. allowing the entire desired signal to pass thru without distortion (IMD) nor excess group delay, AND reducing/eliminating unwanted signals, just a few dozens of hz away from the filter edges...

Also, be aware that the M-802's main receiver (as opposed to the narrow-band DSC receiver) uses no RF amp in the receive chain...just like my beloved (and 35 year old) Drake TR-7's, the "front-end" of the M-802 IS the first mixer (a hi-level DBM), so and with hi-quality, low-phase noise LO's (and a good 15khz wide 1st IF filter, and 10khz 2nd IF filter), actually places the M-802 in the very top end of HF receivers on the market today (actually even better than radios selling for twice or three times the price!)...

The fact is that there are NOT "variable bandwidth" filters in the DSP module, but rather are "fixed" filters for the mode used...
And, hence it just get the blood of many "hams" flowing!!!
'cause there just ain't enough knobs and controls!!!


Bottom line:
It's a great receiver, but unless you're a software engineer and/or have access to the IC-756ProII firmware, etc, there is little you can do about the "fixed" bandwidths...

I hope this helps...

73,
John, KA4WJA
s/v Annie Laurie
OK, so if I understood all this correctly, the filtering in phone modes is perfectly fine; its just not adjustable, correct? And this is perhaps a result of FCC standards for marine SSB? And it sounds like much of the filtering IS done in DSP - very interesting.
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Old 27-02-2014, 21:40   #38
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Re: Icom M-802 Instr Videos(basic-adv) & LIVE DSC-Distress Call

Dockhead,
Sorry I did address this directly...
Quote:
Originally Posted by Dockhead View Post
OK, so if I understood all this correctly, the filtering in phone modes is perfectly fine; its just not adjustable, correct? And this is perhaps a result of FCC standards for marine SSB? And it sounds like much of the filtering IS done in DSP - very interesting.
1- Yes, the filtering for SSB (or even AM rec) is a fixed bandwidths (2.4khz) and is perfectly fine...and with the IF-DSP's steep skirts, and the low-phase-noise LO's, and lack of recip mixing rec IMD, etc. the results are BETTER than almost any ham transceiver currently on the market (including those costing 2 - 3+ times the price of the M-802), with "adjustable" DSP filter bandwidths...

Also, there is no "if-shift" or "low-end-cut", or "high-end-cut", etc. etc. that so many ham transceiver's DSP firmware have thesedays....but the high-quality (low-phase noise) LO, and the well-designed IF-DSP, along with a DSP-driven AGC, etc. make the M-802's receiver work better than 99% of the ham transceivers on the market today....which proves that all the "bells 'n whistles" can't make up for crap design/manufacture...and that excellent design/manufacture doesn't need too many "bells 'n whistles"...



2 - Yes, the overall excellent performance (receive and transmit) is the result of designing / building to comply with a stringent standard, rather than building to what the marketing dept. says what will sell the most/fastest...
(understand that the standards are almost all pertaining to transmit, but in order to get the transmitter up to the standard, and still having a feature-rich radio rather than stripped-down/bare-bones rig, this aids in obtaining excellent receiver performance...)

You may wish to check out this thread for some info on transmit spectral purity and transmit IMD of marine HF vs. ham HF transceivers...
Icom 725, switch to SSB




3 - Yes, ALL the filtering takes place in the IF-DSP module....
Although there are first and second IF filters ahead of the 3rd IF DSP module, they do NOT set nor "control" the receiver (nor transmitter) bandwidths, the IF-DSP module provides the filtering...




I hope this helps clarify things...

John
s/v Annie Laurie
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Old 02-06-2014, 09:45   #39
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Re: Icom M-802 Instr Videos(basic-adv) & LIVE DSC-Distress Call

John

These are fantastic videos!! I learned so much even after using the 802 for more than 10 years. A BIG Thank you and I am sure I echo everyone else who has a M802 and struggles with the manual.

I couldn't catch the type of headphones you recommend. I have a pair that are falling apart and want to get another set.

Regards

Chuck
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Old 02-06-2014, 10:02   #40
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Re: Icom M-802 Instr Videos(basic-adv) & LIVE DSC-Distress Call

Chuck,
You're very welcome...
(btw, heard 'ya on the MMSN the other day, I think you had just anchored in Panama....sounded great..)


As for headphones...
Quote:
Originally Posted by chouliha View Post
I couldn't catch the type of headphones you recommend. I have a pair that are falling apart and want to get another set.
a) Just about any will do...but, a comfortable pair of "communications" headphones rather than hi-fi music headphones can make a difference if you're using a crappy radio (not the M-802)...

b) Do NOT spend a lot of money on them....
A great pair of headphones will be $50 - $80...and even a cheap, non-name pair will work okay...
NO need to look at noise-cancelling phones, etc....(they will not do much for 'ya on a sailboat, nor will they do much that the M-802 is already doing...)

c) In warm weather I prefer "on-ear" headphones, rather than "over-the-ear" headphones....it makes them easy to wear (and allows you to also hear if an alarm/horn sounds while you're on the radio)...

d) As for specifics....
I use a pair of Kenwood HS-6 headphones on-board.....been using for years (both on-board and on-shore at home)...
They're about $50 - $60, and although they're lightweight, they do last!!
Kenwood HS-6 Headphones HS6

e) I also have a pair of cheap (free) headphones from United Airlines...that I carry as a spare pair....and they work good as well....
(I also have a cheap pair of no-name phones, $5....in a locker somewhere??)



So, to sum up...
I use the Kenwood HS-6 phones and love 'em....but on the M-802, just about any set will work better than trying to use the speaker when signals are weak / noisy...


Fair winds..

John
s/v Annie Laurie
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Old 02-06-2014, 20:38   #41
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Re: Icom M-802 Instr Videos(basic-adv) & LIVE DSC-Distress Call

Thanks John

I do have some of those cheap headphones so they will do for now. Currently up in NW panama getting ready to do the slog to Ecuador next week.

Kind regards

Chuck
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Old 03-11-2014, 16:00   #42
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Icom M-802 "Open Mode" (Open/Ham/Dial vs. Standard "marine mode")

Earlier this year, I heard that new Icom M-802's are being delivered to retailers in the "Standard Marine Mode" (which does not allow for user programming of various frequencies into your user channel list, nor use of "VFO Mode", etc.) rather than the "Open Mode" (which is what is described in the manual, and allows you to not only use the M-802 on the ham radio bands / in "vfo mode", but also allows front panel programming of the "user channels"), but unfortunately this info just went in one ear and out the other....

Then yesterday, I had a gentleman on-the-air ask me how to program his "user channels", and a second sailor popped-up right then and asked the same thing...(both were new M-802's and both sounded good on-the-air)

After a few minutes of on-air discussion, it became apparent that both of these guys' radios were not set up the same way (different software versions?) as earlier M-802's....

It was Sunday and I was advising contacting Gary at Dockside Radio in the morning (Monday), and/or Icom tech support.....and even said that Gary probably has something about this on his website...

It was a few minutes later that the first sailor came back on-the-air to tell us that he fixed the problem by placing his radio in "Open Mode" and said that he got the procedure from Dockside Radio's website...
(Thank you Gary!!)

So....
So, if you have an Icom M-802 and cannot program your "user channels", nor use the "VFO Mode" on the ham radio bands, it is because your radio is in "Marine Mode", rather than the "Open Mode" (even though the "Open Mode" is what the Icom manual shows!)
And, the good news is that switching your M-802 to "Open Mode" is VERY easy and takes just 2 seconds, literally!!

Gary Jensen, Dockside Radio, has the exact procedure for programming the M-802 (including placing the radio into "Open Mode"),laid out for you on his website...

Icom M-802 Programming Instructions


But in brief, you're turning the radio OFF...
Then pressing and holding down three different buttons, and then while holding those three buttons down, pressing the power button, turning the radio ON....


And, that's it....
Your M-802 is now in "Open Mode", and you'll be able to program your "user channels" and use the "VFO mode" on the ham bands, etc...


With the radio OFF, the three buttons you press and hold down are:
"Mode", "2", "TXF/TX"
And, while holding those buttons down, turn the radio ON by then pressing the "Power" button...
And, you're done....the radio is now on and in the "Open Mode"



I want to say a big thank you to the skipper/radio op of s/v Corsair, who not only brought this back to my attention, but also provided the solution to us!!!
(and a big thank you to Gary at Dockside, as well...)


I hope some find this useful...

Fair winds...

John, KA4WJA
s/v Annie Laurie, WDB6927
MMSI# 366933110
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Old 15-01-2015, 13:29   #43
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Re: Icom M-802 Current Draw

I have some additional info to share...


Working with a ham radio manufacturer who is looking into improving their transceiver's transmit IMD, he mentioned that it seems the M-802 used a fair amount more power than typical "100-watt" ham rigs did, and asked me if I had the current draw figures (which I did for the most part, but I went ahead and did a new round of tests..)

Here are the Icom M-802 current draw figures (normal production run tolerances might be reflected in other M-802's having minor variations on different bands/freqs, but overall these should be very close for all M-802's...)

The stand-by and receive current draw...
Under stand-by, radio turned off, the TCXO draws about 100-110ma (~0.1amps), and on receive w/ audio, in all modes, it draws about 2.1 amps....all at 13.7vdc


My M-802 is run off a large (1125 A/H) battery bank, charged via a large solar array....and early this morning the battery voltage was 13.7vdc....a short run of 2ga wire powers the radio, with typ. max voltage drop of about 2%...giving me about 13.3-13.4vdc at the radio this morning, at the max current draw of 29.4 amps...


So, here are the overall current draws of the radio on the various bands (subtract 2.1 amps, the current draw in receive, for transmitter-only current draw), at approx. 140-150 watts output...

The zero-signal, mic-keyed but no modulation, current draw was 5.4 to 5.5 amps on all bands, 160m - 10m...

Band ```` SSB-whistle````` FSK Carrier (PACTOR-I)
160m````` 25.6amps`````` 25.6amps
80m ``````28.7 ````````` 28.7
40m ``````25.6`````````` 25.6
20m ``````28.7``````````28.8
17m```````24.7 `````````24.6
15m```````29.3 ``````````29.4
12m ``````24.4```````````24.3
10m ``````24.6``````````` 24.5


PACTOR-II is an approx. 50% duty-cycle mode, so "average" current draw in PACTOR-II would be about half of the FSK PACTOR-I figures....and PACTOR-III's duty-cycle varies from ~ 30% to ~65% (depending on speed), so your "average" current draw in P3, will be 30% - 65% of the FSK PACTOR-I figures...

(FYI, the M-802 is spec'd at 30 amps, max current draw @ 13.6vdc....and all of these figures are about typical for a 150-watt marine HF transceiver....and yes, that is more than your typical "100-watt" HF ham rig...)


All measurements were done near the radio, with a fairly new Klein clamp-on meter (which has proven to be within 0.1 amps of other meters I have tested it against), at ambient temp of about 70*F....with battery voltage of 13.7vdc, and voltage at radio of approx. 13.3-13.4vdc under full current draw of ~ 29amps...

So, when people tell 'ya that you need to figure on 30 amps of current draw from a Marine SSB radio, they are correct....judge and size your wiring run accordingly...



I hope this helps...



Fair winds to all....

John, KA4WJA
s/v Annie Laurie, WDB6927
MMSI# 366933110
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Old 17-02-2015, 08:38   #44
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Re: Icom M-802 Instr Videos(basic-adv) & LIVE DSC-Distress Call

Hello to all,

Since posting my earlier series of videos about HF Maritime Communications (and specifically delving into the details of operating the Icom M-802), "Icom M-802 Instr Videos(basic-adv) & LIVE DSC-Distress Call", http://www.ssca.org/forum/viewtopic.php?f=5&t=16779 , I've had some questions regarding DSC (Digital Selective Calling)...

Some of these questions about DSC came from those who truly had no understanding of what DSC was, nor how it works, let alone how to use it.
And, some recent discussions with some SSCA folks has showed that there are many sailors / cruisers out there (and many more prepping or dreaming) that have gotten little practical education from expensive "communications webinars", let alone any free boat show seminars!

These facts promoted me to make some new videos, the first group of which tackles HF-DSC (Long-range Digital Selective Calling), which are designed to educate non-technical layperson-sailors in how "these blasted radio things" work, as well as show real-world LIVE demonstrations of actual on-air use!

(But, like my earlier series of videos, I suspect that many seasoned radio operators will also find them to be helpful...)

Here are links to my new DSC videos....
(Please note that the last two videos are ONE video, just couldn't upload it all at once so it ended up having to be broken into 2 parts....But, you should watch these last two videos back-to-back, in order to fully understand each of them....)

HF-DSC - Digital Selective Calling, Basic Explanation

http://www.ssca.org/forum/viewtopic.php?f=5&t=16779



I hope everyone enjoys them!

I'm also working on some videos showing simple/easy, and very reliable ways to "get weather" info/forecasts while at sea and in remote areas....without breaking your budget!
Hope to post 'em soon!




Fair winds to all!


John, KA4WJA
s/v Annie Laurie, WDB6927
MMSI# 366933110
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Old 17-02-2015, 10:20   #45
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Re: Icom M-802 Instr Videos(basic-adv) & LIVE DSC-Distress Call

Again, not sure about the Cruiser's Forum software, but here is the other HF-DSC video (that didn't show up above), describing how-to call another boat on HF-DSC..


Fair winds...

John, KA4WJA
s/v Annie Laurie, WDB6927
MMSI# 366933110



"Calling other boats using HF-DSC"

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