Maybe a dumb GPS quesiton

[TwoBallScrewBall]

If I set the cruise control and a waypoint on my GPS in my RV, can I leave the wheel to make a sandwich in the back?<br /><br />No, seriously... here's the question.<br /><br />I have a Garmin GPSMAP 230. No WAAS. Any way to make it WAAS enabled, with maybe a WAAS antenna? Or is that coded into the unit's firmware? I emailed Garmin Tech support but never got a reply. <br /><br />Thanks!

 

[18rabbit]

Re: Maybe a dumb GPS quesiton

If I set the cruise control and a waypoint on my GPS in my RV, can I leave the wheel to make a sandwich in the back?

Others have tried it. I suspect you will have similar results. <br /><br />I have an Icom non-WAAS chartplotter. I talked to ICOM about what you are asking...so I don't consider it a dumb question. I was told any WAAS enable antenna would work. The WAASing is done in the antenna, not the chartplotter. You should check with Garmin but my understanding is you should be able to do it. The difference in NMEA interfacing of a generic GPS and a WAAS GPS antenna is a single identifying character in a data field. It has nothing to do position, direction, course speed, etc. That character is used to flip a soft-switch that enables features in some more advanced chartplotters, like Simrad’s.

 

[TwoBallScrewBall]

Re: Maybe a dumb GPS quesiton

Man that would be good news. I love my Garmin big screen GPS but for night navigating I use my handheld because it's that much more accurate for tight channels and such. <br /><br />I hope to get a definitive answer from Garmin. But thanks for the ray of hope!

 

[chuckz]

Re: Maybe a dumb GPS quesiton

Error correcting is done in the antenna? I'm skeptical to say the least. Signal receiving may be done in the antenna but I think the signal processing and subsequent error correction has to be performed in the GPS. I beleive the GPS is either WAAS enabled or it isn't.<br /><br />18rabbits response seems to indicate that in his unit the WAAS software, already in the GPS, is toggled on and off automatically by the antenna interface. Garmin's website lists models that are WAAS enabled. The conclusion being those that aren't listed aren't WAAS enabled.<br /><br />Look at it this way. If you connect a FM antenna to your GPS, the antenna will receive local FM broadcasts but the GPS won't "decode" them.

 

[BillP]

Re: Maybe a dumb GPS quesiton

My old 12 channel Eagle gps has a menu option to enable/disable WAAS.

 

[jlinder]

Re: Maybe a dumb GPS quesiton

My GPS lets me turn WAAS on and off. They state that if you do not have a valid WAAS signal you should turn WAAS off for better accuracy.<br /><br />I agree with L.I. Chuck - WAAS is in the receiver, not in the antenna. It maybe that the wrong antenna will not receive WAAS and that is what they are talking about.

 

[18rabbit]

Re: Maybe a dumb GPS quesiton

It might be as you guys are suggesting.<br /><br />See this WAAS antenna. Furuno web site requires you accept cookies.<br /><br />]&Product=com.webridge.entity.Entity[OID[2E09C896387BC6408F30D6B732C70C8F]]&ProductCategory=com.webridge.entity.Entity[OID[014ED823A9FA064CA568056E604A5267]]&Tab=com.webridge.entity.Entity[OID[610B2768C391FB40A6D1D849554A5C1A]]]http://www.furuno.com/Furuno/Rooms/DisplayPages/LayoutInitial?Container=com.webridge.entity.Entity[OID[966441EBECC7854FB1A76AF8520AC6FE]]&Product=com.webridge.entity.Entity[OID[2E0 9C896387BC6408F30D6B732C70C8F]]&ProductCategory=com.webridge.entity.Entity[OID[014ED823A9FA064CA568056E604A5267]]&Tab=com.webridge.entity.Entity[OID[610B2768C391FB40A6D1D849554A5C1 A]]<br /><br />Page 12 of the manual tells you how to hook it up for non-Navnet (Furuno) applications. The WAAS-GPS receiver is built into the antenna. Output is NMEA0183. The antenna’s GPS data will transmit to any chartplotter that accepts NMEA.<br /><br />DTM – geometric datum<br />GGA – global positioning system fix data<br />ZDA – UTC date / time <br />VTG – course and ground speed<br />GLL – graphic position lat/lon<br />RMC – recommended minimum specific GPS/transit data (update freq)<br /><br />Also NOTE 3 on page 12 states the antenna is not receiving in WAAS mode when connected to a DGPS beacon antenna. Doesn’t say if it is when not connected to a DGPS beacon.<br /><br />If connected to a Furuno RD-30 (remote display), the antenna does not receive in WAAS mode. Nothing about the RD-30 says it is WAAS enabled. So maybe there is something to the suggestion the chartplotter must be designed WAAS enabled to receive WAAS with this antenna.

 

[jlinder]

Re: Maybe a dumb GPS quesiton

The manual for the antenna refers to "any NavNet product capable of receiving WAAS and GPS information". See link http://www.furuno.com/Furuno/Doc/0/A7J3Q0IHE23KL9QQEP9KAQCB60/NavNet+Brochure+4-12-04.pdf , page 8.<br /><br />WAAS is built into the receiver.

 

[TwoBallScrewBall]

Re: Maybe a dumb GPS quesiton

Garmin said no. So that's the answer.

 

[Triton II]

Re: Maybe a dumb GPS quesiton

They're right... A friend of mine tried it with his 230 attached to my 188's (Waas capable) antennae. Didn't give him Waas.

 

[gss036]

Re: Maybe a dumb GPS quesiton

Jack L, have you been able to verify the part about turning off the WAAS if you don't get a good signal, that it is more accurate? I am up here in the Pacific Northwest, Puget Sound, right at the Candadian border and I very seldom have a decent signal om my 176C.

 

[18rabbit]

Re: Maybe a dumb GPS quesiton

My understanding is the WAASing is processed in the receiver. In the case of that Furuno antenna, it is active; takes a 12-24v supply for the GPS receiver inside the antenna. It does the WAASing there. The Furuno antenna/receiver outputs NMEA so it should be able to provide GPS data to any unit that can accept NMEA GPS data sentences.<br /><br />If the antenna is hooked up to Furuno equipment you have the option of turning the antenna/receiver’s WAASing function on/off at the equipment, but the equipment does not do the WAASing. In the event of GPS correcting done by another source (land beacon i.e. DGPS), the antenna/receiver defaults to its default state…WAAS disabled.<br /><br />This may be why the Furuno RD-30 does not receive WAAS GPS from that antenna, although that is the only plug-n-play GPS antenna Furuno makes that is compatible with the no-internal-GPS-functions RD-30. It does not have the ability to toggle the antenna/receiver’s WAASing. The default state for the Furuno WAAS-GPS antenna/receiver is the WAAS function is disabled.<br /><br />It might be that you can hook up the Furuno WAAS-GPS antenna/receiver to another piece of Furuno NavNet equipment and enable the WAAS function, then remove the antenna receiver and place it on a generic GPS display and get WAAS-GPS accuracy. This creative thinking comes from what I’ve read in the manuals on Furuno’s website. I have not asked Furuno about this so it could be that it doesn’t work this way.<br /><br />I have asked ICOM and they Said “yes” any WAAS antenna can be used to receive WAAS accuracy in their chartplotter. The ICOM manual says the chartplotter is WAAS enabled so I am presuming the WAASing is done internally to the ICOM chartplotter. If your Garmin has a NMEA input, that is where you would connect the Furuno antenna/receiver, not at the GPS antenna input. You would need to know you could enable the WAAS function in the Furuno antenna/receiver or your plotter would be receiving generic GPS data.<br /><br />EDIT: Forget it. I just off the phone with Furuno. You can take the antenna/receiver to a different Furuno NavNet system and enable the WAASing, and then disconnect it and take it your generic display and hook it up, but you won’t get the WAAS corrected GPS data. Once NavNet enables the WAASing, the antenna/receiver is looking for other NavNet data sentences as input and when it doesn’t get them it reverts back to its default non-WAAS-GPS mode. Good news! I’m not the first person to ask about this. Possible future upgrade to the Furuno WAAS-GPS antenna/receiver will have a default WAAS-enabled mode, due to a lot of people calling and asking for this feature.<br /><br />Yes, that Furuno GPS antenna/receiver will communicate with any brand of equipment that can receive the NMEA standard GPS data sentences.

 

[chuckz]

Re: Maybe a dumb GPS quesiton

18Rabbit,<br /><br />Ah, What you say makes sense. The GPS receiver is built into the antenna. The NMEA is a digital output containing the decoded GPS data. Basically whatever is plugged into the NMEA output is a display unit. <br /><br />Plugging into the antenna output gives you an analog signal which then needs to be decoded by a GPS receiver. The antenna output acts like any other antenna and does not do any error correcting or decoding.

 

[Boatist]

Re: Maybe a dumb GPS quesiton

WAAS is just an error correction for the other satellites.<br />Many fixed ground stations receive the signals from GPS satellites.<br />Since the station knows it position it can determine the error form the GPS Satellties.<br />Fixed station then sends the error information to the WAAS Satellite.<br />WAAS satellite then send out that GPS satellite XX is off by this much time in fixed station area.<br />Now it is up to your unit to receive the error correction sent out from stations in your area.<br />Then it correct signals for that satellite if you in the same area as the fixed station.<br />This is done in the computer portion of your GPS not in the antenna.<br />Anttena only function is to recieve the signal the WAAS birds send out.<br />Both WAAS birds are Geostationary meaning they are over the Equator at a fixed location.<br />The two WAAS birds for the USA are Pacific Ocean Region (POR) at 178 degrees East longitude Garmin # 47.<br />The second one is Altanic Ocean region west (AOR-W) at 54 degrees west Longitude garmin # 35.<br />If your have WAAS enabled on your unit two channel are reserved these two WAAS birds.<br />So your receiver is 10 GPS birds and two WAAS birds.<br />If you turn off the WAAS then all 12 channels are used for GPS birds so in some cases may help.<br />Since all the WAAS birds are Geostationary at 0 degrees latitude people in the <br />far North or far South may have trouble receiving the WAAS correction signal.<br />The farther North or South you are the lower on the horizon the signal is and the more likely it<br />will be block by mountians, trees, something on your boat ect.<br />I do not belive adding a WAAS antenna will make any difference unless you <br />also change the firmware so the unit knows what to do with the signal.