Garmin 18 xHD Radome versus Simrad 4G

[Dtrombley]

I've been reading posts for several months now and learning a TON. Thanks for all you've taught me so far. Here's my situation: Our new vessel (a 35' trawler) is now under construction. The builder says he is going to install Garmin electronics. My understanding is that Garmin's 18 xHD Radome still uses microwave technology which can be harmful to people if they are too close to it. However, I've read that you can wrap your arms around Simrad's 4G unit when it is operating and not be harmed. For this safety factor, I'd prefer to use Simrad's electronics. I'm expecting that Simrad's radar cannot be integrated in an otherwise all Garmin environment. (Let me know if that's not right.) So, I did more research on Garmin.

In a link to "Important Safety and Product Information" regarding this Garmin radar, I found the statement in the attached file which makes it sound not as 'toxic' as I believed. So, I'm a bit confused. Please enlighten me!

In case the attachment does not make it, here's the statement that caught my attention: "To comply with RF exposure compliance requirements, the device should be installed and operated with a minimum of 20 cm (7.87 in.) between the device and your body."

[Redline452]

Any radar uses microwave energy... some less than others, but I'd install any radar well above crew as much for coverage as for safety. No point in hugging any of them.

[tanglewood]

DTrombley, I applaud you attention to detail. You are absolutely correct about the difference in safety exposure between 4G and a pulse radar like the Garman - i.e. there is almost no difference, and there is zero practical difference.

At 7" away from the Garmin, that RF exposure is down to the same level as the 4G. So unless you plan to make-out with your radar, it simply makes no difference at all. This notion that there is a material difference in RF exposure between a 4G and any other similar sized radar is a firestorm of miss-information.

If you like the garmin system, move forward and don't look back. You aren't missing anything.

[DotDun]

Originally Posted by tanglewood

DTrombley, I applaud you attention to detail. You are absolutely correct about the difference in safety exposure between 4G and a pulse radar like the Garman - i.e. there is almost no difference, and there is zero practical difference.

At 7" away from the Garmin, that RF exposure is down to the same level as the 4G. So unless you plan to make-out with your radar, it simply makes no difference at all. This notion that there is a material difference in RF exposure between a 4G and any other similar sized radar is a firestorm of miss-information.

If you like the garmin system, move forward and don't look back. You aren't missing anything.

What he said!

[a64pilot]

While I like Garmin and think that there is no realistic danger from their Radome if any sense at all is employed, I disagree that the RF output is the same.
It took forever, but I finally found out the output power of a 4G Radar, and its .17 watts, to put that into perspective your VHF output is 25 watts or 147 times times greater.

Last boat I had a Garmin 18HD and a Garmin 740S, a very excellent machine, beauty of a Garmin is ease of use, you don't even have to read the book, it's so intuitive.
My Simrad is likely a better machine in that it has more capabilities etc., but a year later and I'm still figuring the thing out, and I have read the book, over and over.

[tanglewood]

Originally Posted by a64pilot

I disagree that the RF output is the same.

Just to be clear, I didn't say they were the same.

Safety standards look at the RF power per square meter. The Simrad 4G safety claims are based on an industry accepted level of 100W per sq meter, and that is achieved at 0m distance from the dome.

By comparison, a Furuno 4kw dome radar achieves 100W per square meter at 0.1m, which is about 4". The OP quoted specs from Garmin of 7". This is the basis for my statement that "unless you plan to make-out with your radar, it simply makes no difference at all". Another way to say it is that the RF exposure for a Furuno 4kw array at 4" is the same as a 4G array if you are kissing it. So if you want to make-out with your dome, then by all means get the 4G. Otherwise RF exposure is a complete non-issue and shouldn't influence your purchasing decision.

The fundamental difference that generates all this miss-information is that the 4G transmits a continuous, lower power signal, where a pulse radar transmits an intermittent higher power signal. Clever marketing and sales people compare the instantaneous power output of the continuous low power radar with the instantaneous power output of the intermittent high power radar, and the unwary listener concludes there is a huge difference. I mean after all, 4KW vs 250 mw? Holy crap, that's huge, right? It's a marketing managers wet dream. Well, no, it really isn't when you complete the story and look at the RF emitted over a full second, or minute, or hour..... The distance to the 100W/m2 power level tells the whole story, and it's a difference of between 4 and 7 inches from the dome. That's 4-7 inches, not feet, not meters. Inches.

[Nagromxam1]

Originally Posted by tanglewood

Just to be clear, I didn't say they were the same.

Safety standards look at the RF power per square meter. The Simrad 4G safety claims are based on an industry accepted level of 100W per sq meter, and that is achieved at 0m distance from the dome.

By comparison, a Furuno 4kw dome radar achieves 100W per square meter at 0.1m, which is about 4". The OP quoted specs from Garmin of 7". This is the basis for my statement that "unless you plan to make-out with your radar, it simply makes no difference at all". Another way to say it is that the RF exposure for a Furuno 4kw array at 4" is the same as a 4G array if you are kissing it. So if you want to make-out with your dome, then by all means get the 4G. Otherwise RF exposure is a complete non-issue and shouldn't influence your purchasing decision.

The fundamental difference that generates all this miss-information is that the 4G transmits a continuous, lower power signal, where a pulse radar transmits an intermittent higher power signal. Clever marketing and sales people compare the instantaneous power output of the continuous low power radar with the instantaneous power output of the intermittent high power radar, and the unwary listener concludes there is a huge difference. I mean after all, 4KW vs 250 mw? Holy crap, that's huge, right? It's a marketing managers wet dream. Well, no, it really isn't when you complete the story and look at the RF emitted over a full second, or minute, or hour..... The distance to the 100W/m2 power level tells the whole story, and it's a difference of between 4 and 7 inches from the dome. That's 4-7 inches, not feet, not meters. Inches.

Navico seem very good at deceptive marketing throughout there different brands.

[Maine Sail]

Originally Posted by Dtrombley

I've been reading posts for several months now and learning a TON. Thanks for all you've taught me so far. Here's my situation: Our new vessel (a 35' trawler) is now under construction. The builder says he is going to install Garmin electronics. My understanding is that Garmin's 18 xHD Radome still uses microwave technology which can be harmful to people if they are too close to it. However, I've read that you can wrap your arms around Simrad's 4G unit when it is operating and not be harmed. For this safety factor, I'd prefer to use Simrad's electronics. I'm expecting that Simrad's radar cannot be integrated in an otherwise all Garmin environment. (Let me know if that's not right.) So, I did more research on Garmin.

In a link to "Important Safety and Product Information" regarding this Garmin radar, I found the statement in the attached file which makes it sound not as 'toxic' as I believed. So, I'm a bit confused. Please enlighten me!

In case the attachment does not make it, here's the statement that caught my attention: "To comply with RF exposure compliance requirements, the device should be installed and operated with a minimum of 20 cm (7.87 in.) between the device and your body."

Why would you not look include the 18" Garmin Fantom domes in your research? Their new Doppler target identification is quite amazing in that it can highlight targets moving towards you in one color and targets moving away in another & stationary targets in a third color.

Garmin Fantom - Panbo

[Dtrombley]

Thanks, Maine Sail and to all others who contributed to this thread. Some more research and the influence of your replies caused us to go with Garmin equipment. The Garmin GMR Fantom 18 dome radar is the one we chose.