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Old 14-04-2016, 08:22   #1
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Icom 7300?

I've got my Icom 802 still in the box and now the 7300 comes along. Any comments on why I shouldn't trade up?
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Old 14-04-2016, 09:14   #2
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Re: Icom 7300?

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Originally Posted by Roy M View Post
I've got my Icom 802 still in the box and now the 7300 comes along. Any comments on why I shouldn't trade up?
Yeah, you'd be trading across, not up!

The IC7300 is a ham radio, not a marine radio, and illegal to use on the marine bands.

The M802 is an excellent marine radio which also works well (and is legal) to use on the ham bands if you have a ham license.

Depends on what you plan to do with the radio.

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Old 14-04-2016, 10:04   #3
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Re: Icom 7300?

Yeah, exactly what Bill said. Panbo has a weird article up about the 7300 that seems to be a misunderstanding of what the 7300 actually is: a standard HF + 6 meter Ham radio. The only thing new is that this marks the first time one of the big 3 (Icom, SH, Kenwood) have released a radio with a direct down convert receiver, i.e. SDR instead of an analog superhet receiver. So far it looks very promising in terms of performance but that has really nothing to do with marine SSB. I guess I will point out that there are MARS mods already up around the net for it so that TX can be opened up on marine bands. But as with any Ham radio transmitting on marine ham bands in anything other than an emergency is both illegal and potentially interference generating on adjacent marine channels. I doubt the TX performance of this radio is any better than other Icom radios. There is also no DSC. Stick with the 802.

Icom has announced a new SSB called the GM800 but I don't think it's shipping anywhere yet. There weren't a lot of details on it last I searched, but it appears to be aimed at GMDSS usage, i.e. commercial shipping. So it's possible it's not intended to replace the 802, but instead augment it for the commercial marine market. If that's true it's likely to be a lot more expensive than the 802.
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Old 14-04-2016, 11:03   #4
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Re: Icom 7300?

Roy,
Bill and gjorgensen are correct....
Stick with your M-802....
(and watch the videos and read the stickies)

Icom M-802 Instruction Videos
https://www.youtube.com/playlist?lis...rC-8QKVyMb4tVr


HF-DSC Videos
https://www.youtube.com/playlist?lis...ga2zYuPozhUXZX


Offshore Weather Videos
https://www.youtube.com/playlist?lis...zdjTJjHlChruyY



http://www.cruisersforum.com/forums/...tc-133496.html

http://www.cruisersforum.com/forums/...ll-114734.html

http://www.cruisersforum.com/forums/...os-141406.html






Regarding the Icom GM-800....
Yes, it is a GMDSS compliant HF-DSC-SSB-Radiotelephone (which is what the M-801GMDSS was supposed to be, but when the EU changed some rules, Icom said WTF and stopped production of it)...
BUT....
But, understand that the GM-800 is a 24vdc / 110-250vac radio, NOT a 12vdc radio....and it has some GMDSS features that nobody on a cruising boat needs (or wants)!
(and quite possibly is not capable of out-of-band operation / ham band operation???)
So, for anything smaller than the MegaYacht crowd, it's the M-802 that is THE radio, not the GM-800...(not to mention that the GM-800 is > twice the price of the M-802...possibly even 3 times the price...)
Quote:
Originally Posted by gjorgensen View Post
Icom has announced a new SSB called the GM800 but I don't think it's shipping anywhere yet. There weren't a lot of details on it last I searched, but it appears to be aimed at GMDSS usage, i.e. commercial shipping. So it's possible it's not intended to replace the 802, but instead augment it for the commercial marine market. If that's true it's likely to be a lot more expensive than the 802.



Fair winds..

John
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Old 15-04-2016, 17:42   #5
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Re: Icom 7300?

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Originally Posted by ka4wja View Post
Regarding the Icom GM-800....
Yes, it is a GMDSS compliant HF-DSC-SSB-Radiotelephone (which is what the M-801GMDSS was supposed to be, but when the EU changed some rules, Icom said WTF and stopped production of it)...
BUT....
But, understand that the GM-800 is a 24vdc / 110-250vac radio, NOT a 12vdc radio....and it has some GMDSS features that nobody on a cruising boat needs (or wants)!
(and quite possibly is not capable of out-of-band operation / ham band operation???)
So, for anything smaller than the MegaYacht crowd, it's the M-802 that is THE radio, not the GM-800...(not to mention that the GM-800 is > twice the price of the M-802...possibly even 3 times the price...)
Good point on amateur bands. My understanding is that SOLAS/GMDSS radios from other manufacturers are not capable of operating in ham bands, at least not without a heavy-handed modification. That makes sense given the use case for a GMDSS radio: continuous DSC watch keeping and operation for marine safety and rescue operations on the various marine SSB channels. It would probably be desirable to NOT allow their use on ham bands. The ships couldn't conduct any business on the ham bands, and marine safety would be carried out on the marine bands. I'm with you that I think that radio will be extremely expensive.

As an aside, I think if you want to carry a ham radio in addition to an SSB, the 7300 may turn out to be an excellent choice if it proves to perform as well as it appears to so far. It's compact, the receiver works quite well, although not nearly as good as SDR rigs from smaller manufacturers (e.g. Flex, which are much more expensive), it's easy to use, and the RX power draw is considerably less than most superhet radios including the 802. It's certainly not the first or best SDR rig on the market, but may fill a nice niche for boaters if you don't need the punch of a Kenwood TS-480hx.
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Old 16-04-2016, 13:06   #6
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Icom 7300?

I would recommend an Elecraft K3S if you want a great ham rig to complement an M802. Compact, almost unparalleled receiver performance, and low transmit IMD. Its an SDR with knobs, but omits the flash of most of the "KenYaeCom" rigs. Lots of options you can install yourself or have the factory do it. Ongoing direct factory hardware support and regular firmware upgrades. Made in USA.

OK, Elecraft Fanboy mode Off. 😁

Chip


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Old 16-04-2016, 13:35   #7
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Re: Icom 7300?

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Originally Posted by SoonerSailor View Post
I would recommend an Elecraft K3S if you want a great ham rig to complement an M802. Compact, almost unparalleled receiver performance, and low transmit IMD. Its an SDR with knobs, but omits the flash of most of the "KenYaeCom" rigs. Lots of options you can install yourself or have the factory do it. Ongoing direct factory hardware support and regular firmware upgrades. Made in USA.

OK, Elecraft Fanboy mode Off. ��

Chip


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Chip,

The Elecraft K3S....like all Elecraft products...is a wonderful piece of gear. Unparalleled, really.

However, IMHO it's a poor choice for onboard use, because inter alia:

. it's cost is over $3,000
. it doesn't even have a general coverage receiver, without the option
. it's incredibly complicated and daunting for many hams, particularly new ones
. there are many other ham radio choices which have excellent performance and cost much less.

There are dozens of good ham rigs suitable for marine use, both new and used, priced from about $200 used to $1,500 new.

While I'd love to have the Elecraft K3S in my shack at home, I'd be very unwilling to put this great piece of gear on my boat.

By the way, I see we have somewhat the same taste in boats: I had a Catalina 22 for 10 years & loved it, and I lusted after the Valiant 40 for many years before settling on another Perry-designed boat with a similar underbody: the Golden Wave 42, which I've cruised for 25+ years.

Bill
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Old 08-08-2020, 17:52   #8
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Re: Icom 7300?

Gentlemen,
Please clarify why the IC-7300 is illegal on the marine SSB bands, provided user is properly licensed, and the radio has the mod for wideband operation? Once the signal leaves the antenna, meets all the mod, bandwidth, filtering, etc requirements for the band of operation, it is independent of radio generating the signal. As a licensed ham, I am entitled to mod my radio as long as I meet FCC requirements and don't mind voiding my warranty. Are there some unique requirements for the marine SSB waveform?
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Old 08-08-2020, 21:00   #9
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Re: Icom 7300?

Because by international treaty non-emergency transmission on marine SSB frequencies is only legal using a radio certified for use on those frequencies. No existing ham transceivers are certified for such use, and most will not meet the requirements It is not illegal to modify your radio such that it's capable of using the marine bands, and it's also legal to use it on marine bands in an emergency.
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Old 08-08-2020, 22:48   #10
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Re: Icom 7300?

Bob,

Welcome!
Welcome to Cruiser's Forum!

And, have a seat....we're going to be here a while... LOL


As someone who has spent a good deal (45+ years) of my life dealing with interference issues, in both my career in communications and in amateur radio....whether microwave, satellite, HF, and VHF/UHF....


And, as someone who has spent a good deal (50+ years) of my life on-the-water, cruising, sailing offshore, etc...and dealing with radio communications for decades (both marine and ham), at sea...

Further, as someone who has taught seminars about IMD, etc...

I'll gladly spend a couple minutes answering your question... (hint: it's mostly about the poor IMD and a mic gain control)

(btw, IMD = Inter-Modulation Distortion....which in simple terms is how we measure / quantify level of non-linearity, which causes interference and inefficiencies....and, of course, cannot be "filtered out" by the transmitter, as poor IMD is just the result of poor transmitter design, and a little bit about those with mic gains cranked too high!)




1) Although the IC-7300 is a nice ham rig, neither it, nor any ham radio made in the past 40 some years, has ever been Part 80 Certified for use on anything other than the amateur radio frequencies (nor Certified by any other nation, nor ITU, etc. for maritime use, nor use on any other radio service) ....

Remember, in the amateur radio service (ham radio) there are no specific in-band interference specs/standards, and it is up to the licensed amateur radio operator to adjust their radio properly so they do not cause interference to other stations (and must accept interference from other stations)...

So, it is illegal to use the IC-7300, or any ham radio, on the maritime bands, or on any band/frequency it was not designed/certified for....

Hands down, full stop, period.

Thhhhaaaattss all folks...




2) But, you asked for someone to tell you why....so...

The reason it is not certified for this use (other than Icom didn't design it for, nor did/would Icom submit it for certification) is that it (and all other ham radios made in the past 40 some years), does not produce a clean signal....i.e. its transmit spectral purity is poor....
That's an unfortunate fact, but a fact none-the-less!

The transmit spectral purity / transmit IMD of the IC-7300 is significantly worse than what the Maritime Mobile Service Part 80 (and ITU IMO) specification calls for...in the US, this is governed under US FCC Part 80 rules & regs...

Now, in comparison with other "modern" ham radios made today and in the past few years, the IC-7300 is about average....but worse than ham radios of the 1970's and early 80's...and significantly worse than the maritime specs...


This is commonly known as "splatter"...

And, these "specs" are measured with the radio operated as it is designed to / at its designed settings...and again, it doesn't come close to meeting these specs...

Of course, since the IC-7300 (and all other modern HF ham radios) has a "mic gain" control, and other transmitter controls / adjustments, the IC-7300 (and most other modern HF ham radios) can be adjusted to transmit an even worse signal, with even worse transmit spectral purity / worse transmit IMD....which would be very, very bad...

Understand that this IMD / poor transmit spectral purity is almost never noticed "on-frequency", meaning 99.9999% of the time, you can be talking with someone who says you "sound fine", but off-channel / off-frequency your transmit PA is producing splatter / IMD, and causing problems for others!


Also, let's not forget that Maritime, Aviation, and commercial/Fixed/land-mobile services are "channelized", and the channel usage and assignments are very specifically designed to not cause interference with adjacent users....and since ham radios (such as the IC-7300) are designed with a VFO, and not specifically designed for channeled use (yes, I know it has memories), it can be tuned off-frequency from the designated channels and cause significant interference...


{BTW, there are a few ham rigs made in the past 50 years (but, none in the past 30-35 years) that could pass the stringent transmit spectral purity and IMD specs for maritime operations, such as the old JRC JST-245 and the Drake TR-7....but, note that Drake made commercial versions of the TR-7, with synth digital vfo, to meet the frequency-stability spec, the TR-77 (for maritime use) and the TR-4310 (for commercial fixed/mobile use), which did of course pass....and JRC, used the same basic chassis and guts of the 245 for some of their marine radios of the day....so, it stands to reason that they also passed the spec...but, that's about it...}














3) The radio is designed to operate in the ham bands, and as such, even the relatively poor transmit specs get worse when operated significantly out-of-band....

Understand there is a big difference between operating a few khz outside of the ham bands, such as in MARS / CAP operating...versus operating several mhz outside of the designed band...

It might not seem to be "way out-of-band", but in terms of percentage and partial-octave, 8294khz and 6224khz, are quite aways away from 40 meters....as are 12359khz and 16528khz, way out-of-band of 20 meters....etc., etc...

This is a significant issue that many will never talk about....but it exists and is another reason you cannot operate an IC-7300 on the marine bands...



{BTW, MARS and CAP have fairly strict rules these days on what ham radios can be legally operated on their frequencies....and I'm not sure if they allow the 7300, but think not....as there are only a few HF ham rigs that do qualify, and its a darn easy spec to meet, so that should tell you something...just because you might find a mod on the internet that says you can do this (MARS mod), doesn't make it legal, nor acceptable...}





4) And, specific to our applications, on-board a boat...most ham radios suffer from issues when operated on "battery voltages" of 12.0 to 12.6vdc (at the radio), versus a regulated 13.8vdc....

Please note that to be Part 80 Certified, the radio needs to meet all of its specs, when operated over a wide range of voltages...(11.5 to 15.5vdc, for a 12-volt radio, I think)

And, most ham radios, even in the ham bands, have some transmit issues when voltages fall below 13vdc....and most / all modern hf ham radios (including the 7300) have serious transmit issues (increased transmit IMD, worsening spectral purity) when voltages fall to and below 12.5/12.6vdc....
And, when attempting to transmit in SSB mode, at these lower voltages many will start "fm'ing" (warbling) and cause serious harmful interference....

And, some/many ham rigs will just shut-down when transmit is attempted as voltages fall below these levels...

Oh, and btw, remember that while your batteries might show 12.5vdc, when you figure even a slight 3% voltage drop to the rig, that becomes 12.1vdc at the radio....and that's bad....very bad...
(and, that doesn't take into account the possibility of having a fairly depleted battery bank and/or a too-small battery bank....which will be pulled further down in voltage, when attempting transmit...)


This is why so many hams trying to run HF mobile, need a "battery booster", which not only can cause RFI, but also add inefficiencies in the DC power system (meaning you end up drawing more power from your batteries, draining them quicker, there-by exasperating the problem...and so on and so on...)




5) Further, while you can modify your radio anyway you choose, it is you the licensed ham operator, that is responsible for what you transmit with it....the good, the bad, and the ugly!

And, no....even if you have a Maritime License, you still cannot use a ham radio on the maritime bands, nor the aviation bands, etc. etc!!






6) On a side note, in the past 40 years, I have heard my share of illegally modified ham radios used on the marine bands, and with one or two exceptions, they ALL were interfering off-channel / off-frequency....and many were causing many problems for others on-the-air...(most were oblivious)

As a quick example....recently (late 2018) I heard two sailors using ham radios on the 4mhz marine band....they weren't too strong, but the reason I heard them was that their transmit splatter was interfering with my comms....so, I spun around and found them...

They were yacking away on some non-channeled freq in the marine bands, oblivious to the interference they were causing....I listened for a couple minutes, trying to find a way to politely interrupt and let then know what their radios were doing....
During this time, one mentioned he was using an IC-706 and one was using an IC-718 (one was about 600 miles from me, and the other one was 250-300 miles from me...they were about 250-300 miles apart), and both were splattering...

I was about to say something when they decided to move up to 8mhz, 'cuz they were having trouble copying each other....and the frequency they said they were moving to was 1khz off from an HF Aviation channel used for North Atlantic Route, trans-oceanic HF aviation!!
WHAT!!!

I thought, WTF....and quickly called them to warn them....to no avail....they'd already left for 8mhz band....and sure enough, I followed them up and there they were!

The good news is that while I could copy them both very well (much stronger here on 8mhz), they were a little too close to each other to have good comms on 8mhz, at that time....so, after a few "can't really hear you's", they signed off and disappeared...

Neither boat identified themselves with a callsign, just a boat name....so, while I spent a few evenings looking around the internet trying to find how to get in touch with them, I was never able to do so...

And, I often wonder what they would think of some yahoo interfering with aviation (or maritime) comms, if they or one of their loved ones was on-board a plane or ship, reporting a position, or asking for assistance?



Sorry, for the digression...just wanted you to see that are real world consequences of ignoring simple-to-understand rules...






I do hope this helps answer your question?


And, since a used / discontinued Icom M-802 Marine Radio (IF-DSP-based Marine MF/HF-DSC-SSB Radiotelephone) is now about $700 to $1000....
And, the new Icom M-803 (a new SDR-based Marine MF/HF-DSC-SSB Radiotelephone) is about $2400....
https://www.icomamerica.com/en/products/marine/ssb/m803/default.aspx
http://docksideradio.com/

http://www.icomamerica.com/en/products/marine/ssb/M802/default.aspx


https://www.ebay.com/itm/40234716992...&ul_noapp=true


And, there are NO ham radios made, nor ever made, that have DSC....I think the whole discussion of the 7300 on the marine bands is kinda moot, isn't it?


Fair winds.

John



P.S. Btw, in recent years, the Temp-Comp-Cystal-Ocs (TCXO's) in most ham rigs are usually stable enough to maintain frequency within maritime spec, their actual freq accuracy is not usually within spec....way too large variations in production, and no reason to test/adjust for this...

Oh, and the marine radios have Oven-Controlled-Crystal-Osc (OCXO's), sometimes called Oven-Controlled-Master-Osc (OCMO's), and they are built and adjusted to be within spec...at all times...

I mention these in post script, because they are somewhat important to know, but these days are usually a minor issue...




P.P.S. Bob, while I always appreciate those that wish to learn and ask questions, I am a bit surprised that a fellow Extra is asking this question?
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Old 09-08-2020, 08:09   #11
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Re: Icom 7300?

Bob is legally entitled to use his Ham radio, the IC-7300, on all frequencies formally allocated to Ham radio use. Only those. The specific channels allocated to Marine service do not overlap with Ham frequencies. Perhaps he is thinking about the unofficial volunteer Maritime Mobile Service on 14.300 MHz in the Ham band. Of course Bob can use his IC-7300 communicating on that frequency, since it is within the Ham bands, but it is not an officially designated marine service or frequency. And as gjorgensen mentioned above, in a true emergency Bob may use his IC-7300 to get help on an officially designated marine channel or frequency without penalty.
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