SSB HELP for SABA 50

[Pizzazz]

Well, if you remove the cover and look at the amplifier section of any marine HF, you will see how the power splits into two fuses, each driving two transistors, etc. having an independent path for all power components. It is really just for redundancy, you do not want to mess around with fuses, etc. in an emergency. They have other requirements such as fixed microphone (not all but many), ability to override tuned status (i.e. if the tuner fails you can still feed a significant amount of power into the antenna hoping to get at least some of it out, etc. most ham rigs will shut down if not tuned to protect the output power amplifier, etc.). Today, equipment is so reliable that these features are not as important as they were in the past, though.

[Wotname]

Originally Posted by Pizzazz

Well, if you remove the cover and look at the amplifier section of any marine HF, you will see how the power splits into two fuses, each driving two transistors, etc. having an independent path for all power components. It is really just for redundancy, you do not want to mess around with fuses, etc. in an emergency. They have other requirements such as fixed microphone (not all but many), ability to override tuned status (i.e. if the tuner fails you can still feed a significant amount of power into the antenna hoping to get at least some of it out, etc. most ham rigs will shut down if not tuned to protect the output power amplifier, etc.). Today, equipment is so reliable that these features are not as important as they were in the past, though.

Just what country has these requirements as they certainly don't apply to all marine HF radios?

[Paul Elliott]

Originally Posted by Pizzazz

Well, if you remove the cover and look at the amplifier section of any marine HF, you will see how the power splits into two fuses, each driving two transistors, etc. having an independent path for all power components. It is really just for redundancy, you do not want to mess around with fuses, etc. in an emergency.

Sorry, that's not right, at least for the Icom M710 marine transceiver. I just checked the schematic and while the output stage uses two transistors, these are connected in a push-pull center-tapped transformer design. If one transistor dies, the output stage just stops functioning (or functions at a *much* lower power output and with *huge* amounts of harmonic distortion). The driver stage also uses a similar two-transistor center-tapped transformer configuration. And there are no separate fuses for the transistors.

The block diagram may be misleading you -- it shows what *could* be interpreted as independent drivers, but the schematic shows the circuit I described above.

Perhaps the Icom M710 doesn't meet your standards for a marine transmitter, but it was probably the most commonly seen SSB rig in pleasurecraft, up until the introduction of the Icom M802.

FWIW, I just checked the M802 schematics, and it uses a similar push-pull output stage. There's no redundancy in that rig either.

[gjorgensen]

Originally Posted by Paul Elliott

FWIW, I just checked the M802 schematics, and it uses a similar push-pull output stage. There's no redundancy in that rig either.

Beat me to it - I've been inside the 802 (more than once) and it's definitely a single transmitter, with a dual transistor push-pull output stage like you describe. I'd actually describe the transmitter as pretty similar to the IC-746pro, which was around the same vintage, but of course with the crystal oven and some improved filtering.

[Pizzazz]

We'll, the ones I have looked at are the SEA series, the Ray series and Furuno. Icom is more recreationally focused, I believe. On my SEA-235 you have two sets of power wires going to two sets of two transistors (4 altogether), two fuses, giving a total power of 150W. The radio can output either 150W, half that or quarter that. I assumed that all marine radios are like that. My mistake.

[Paul Elliott]

Originally Posted by Pizzazz

We'll, the ones I have looked at are the SEA series, the Ray series and Furuno. Icom is more recreationally focused, I believe. On my SEA-235 you have two sets of power wires going to two sets of two transistors (4 altogether), two fuses, giving a total power of 150W. The radio can output either 150W, half that or quarter that. I assumed that all marine radios are like that. My mistake.

I just checked the service manuals for two different Furuno rigs. Indeed, the FS1575 has two identical power amp sections, connected to a transformer coupler. This is a useful level of redundancy.

On the other hand, the FS1505 has a single push-pull power amp, similar to the Icom 803 and 710. I wonder if the design differences are due to redundancy requirements or just the desire to re-use existing circuitry? But yes, some SSB rigs have a level of redundancy.

[Gerrycooper56]

We had both an Icom 802 and an Iridium phone and although we used the SSB in both Caribbean and Pacific felt the Iridium was more useful. We now have a different boat but bought a new Iridium extreme which transmits gps coordinates on a regular basis which is a useful safety feature. Once NOAA
Phase out the weatherfax then the SSB for us is sort of redundant.

[jimisbell]

Anyone actually use any vintage HAM gear onboard? I am thinking I would like to put my S-Line on board or maybe an old 60s rig.

[TLSparks]

First to answer your question. Commercial ships are required only to monitor the emergency DSC frequencies that the 2nd receiver in the M801E and M802 scan in the background. At this time there is no HF calling frequency that you can hail them directly. A GMDSS task force has recommended what the call the Terry Sparks method to standardize the Individual calling frequencies scanned in DSC Watch. GMDSS plans to change their document in the future, but no schedule for that. As I understand the Australia race clubs have standardized on those frequencies already and have also adopted the Worldwide Group numbers for general calling in regions.


It is always possible to make a Geographical DSC call using one of the emergency frequencies to contact a commercial vessel until GMDSS provides standard DSC Watch frequencies.


With regard to the M801E it is a very good unit, but very overbuilt. Yes it is waterproof, but more importantly, it has a built in DC to DC power supply that will keep the radios voltage constant with battery levels down to 12V if I remember correctly. The down side is it puts out less power, around 100W I believe at all times as opposed to the M802's 150 Watts.



While that may seem like a big deal it is not and the M802 falls off quickly with lower battery levels. 13.2 -> 150 at 12.6 it is down to or under 100W.



There is a very big difference in cost and Icom has stopped delivering the M801E to Europe already and is working on a new HF DCS radio. The commercial version may already be available, but is a 24V unit. It is projected that the M802 replacement will be available in 2020. However, I suspect there will be a significant cost increase with all the new bells and whistles on the new radio.


Since the base Icom assigned channels are more of a sales pitch at everything an M802 can do and I assume the same for an M801E, I created a simple structure that seems to help people get started and have it posted on my web site with a lot of other M802 help. M801E users in Europe tell me the help works fine for M801Es as well. Here is the structure. If you have the programming software, I am happy to send the file. https://www.made-simplefor-cruisers....20Channels.xls


Kind Regards
Terry

[Hoopla]

The decision making process between aquiring a 801e and 802 is quite simple for an Australian flagged vessel.Note the 801e for Europe and Australia used to be identical. That is no longer the case.

1. The 801 has a galvanicaly protected power supply the 802 doesn't.

2. The 801e has a sealed heat sink case with no fan. An 802 is unsealed with a cooling fan and more susceptible to salt laden moisture intrusion.

3. You require a Ships Station Licence that is attached to the ship before AMSA with either issue or attach a MMSI to that DSC device named by model and serial number. They will not accept a 802 or furnish a 802 with an MMSI.

4. If you don't require a HF for either GMDSS security or utilising the DSC polling function both requiring an MMSI then a 802 will suffice, albeit you are operating it contrary to regulation in terms of the Ship Station and Operator Licencing.

5. Communications regulations and enforcement attach to the ships country of registration, not the waters it sits in.

6. Note to the best of my knowledge the only countries that accept the 802 are the USA its territories and affiliates that follow things US. The USA use a dealer MMSI system for one off programming, not the user. Most other countries follow Euro standards or in other words the 801e not the 802. Australia employs a user MMSI multiple programming system independant of the dealer.

7. Australia like a lot of countries no one listens on Marine HF voice any more including commercial vessels, only DSC and for SOLAS vessels that is mandatory world wide over 300 tonne.

[Pizzazz]

I see no logical reason why the MMSI process is so complicated. It may be a lot easier just to use PersonalDSC or a simar software app.

Just out of curiosity, what would happen if I use a US only MMSI number abroad?

[Hoopla]

Originally Posted by Pizzazz

I see no logical reason why the MMSI process is so complicated. It may be a lot easier just to use PersonalDSC or a simar software app.

Just out of curiosity, what would happen if I use a US only MMSI number abroad?

The US system of dealer only unit MMSI programming is a pain but issue of MMSI's appears less regulated than elsewhere.

No problem using authorised MMSI'S outside country of origin, it is an international system administered by each country. See Item 5.

[Paul Elliott]

In the past, and perhaps now, some MMSI numbers obtained in the USA are not recognized by the international database system (ITU?). These are/were obtained through BoatUS and other organizations and were somehow USA-only numbers, typically used with marine VHF radios. MMSI's obtained through the normal USA FCC registration process are recognized worldwide.

[Hoopla]

Originally Posted by Paul Elliott

In the past, and perhaps now, some MMSI numbers obtained in the USA are not recognized by the international database system (ITU?). These are/were obtained through BoatUS and other organizations and were somehow USA-only numbers, typically used with marine VHF radios. MMSI's obtained through the normal USA FCC registration process are recognized worldwide.

That only applies to equipment that does not require a Ships Station Licence and which won't be used outside US waters. To leave US waters with an authorised international MMSI for a HF will first require a Ships Station Licence, other equipment not requiring a Ship Station Licence such as Class B AIS's still require a international MMSI. This is common to most if not all signature countries.

[TLSparks]

There seem to be many on this blog that think the US dealers provide the MSSI number.


The dealer MMSI is only valid for short range/safety devices inside the US waters and is illegal to use on a SSB. Our FCC issues a valid world wide MMSI and the number is sent to the ITU which is input into their database. All GMDSS stations have access to that database.


Seems as though all countries do it differently. US issues with a Ship Station License. Canada issues it separately and uses the M802 as a standard.


My understanding is the M801E is no longer available in Europe and they have not accepted the M802 as a standard. England seems to have the toughest rules on MMSI numbers and mandates they are the only ones that can assign individual and group numbers. I believe this is true in Canada and Hong Kong as well.


If you are not sure if you have an official MSSI and/or to make sure your government sent it t the ITU, go to this site. https://www.itu.int/mmsapp/ShipStation/list