Acquistion Times

I have been using the Nuvi 660 for about 2 months now and acquisistion times vary from several seconds to a few minutes. I do not think I have ever waited more than 4 or 5 minutes to lock on and the norm is much less than that.

I have used various gps devices in rental cars etc. I purchased my nuvi 660 the day after x-mas, i think the unit is outstanding and pretty solid, i have put it through it's paces in the city and out in rural areas and it has responded well so far, if it keeps up this performance for the long hall i'll be happy. I am really pleased with the traffic message channel service, the update responce time is pretty accurate there was an accident on the opposite side of the freeway of a vehicle flipped over and before the EMS/Fire trucks got there it was on my screen within minutes showing the yellow sign with a car flipped over and traffic slowing sign. I thought that was impressive for the amout of time that had passed.

My acquisition times are usually less than one minute if I have open access to the sky. Indoors it takes a little over a minute. Under the guise of skyscrapers, it takes up to 2-3 minutes.

Anyone know details of when the FM transmitter boots up? I have driven as long as 5-10 minutes by which time I have chosen the wrong route to avoid traffic.

Depending upon where I am in Maryland, the indicator light may stay yellow and give no traffic information as it did around BWI airport this morning.

It has a SIRF Star III chipset:

http://www.gpslodge.com/archives/004566.php

Map data of the Garmin is the best and most up to date.

I installed the Garmin GTM 12 FM receiver on my c340 about a week ago and I receive Traffic Data in usually less than a minute never more than 2 minutes. Which FM receiver do you have?

The transmitter that came with the Nuvi 660.

Yesterday, it locked into the FM system shortly after calculating the trip. Today it took about 7-10 minutes.

I don't know if the Baltimore/DC transmitters were having a glitch. I wouldn't even know what the source of those transmissions are. Are there website links?

The traffic info is piggy-backed onto FM radio station signals. If you can receive the station in your market, you'll get the data.

I _think_ this is the company that is doing it:

http://realtimetraffic.net/

There may be others.

HTH,

---Matt

Yup, just looked again and the Nuvi 660 is on their "Featured Product" page.

They also have coverage maps, so you can find out which cities are active.

---m

I wrote to the technical support section of that website for real time traffic.

I will see if I get a response.

I have the same problem with the FM traffic reciever. Sometimes I am almost halfway to work before I get any traffic information. Other times I get it right away.

It took 3-4 miles from the house before I connected.

There was a dead spot just north of the I-95 S and I-495 junction coming from home.

I emailed them and they said one other person noted similar problems and they were looking into it.

I hope they figure it out or I won't be subscribing beyond the trial period. Come to think of it, if it doesn't work soon, I won't have much need for a GPS.

My Buddy has the Nuvi 660 and he and I went out to our cars to check how quickly the data loads. I have a C340 with the GTM 12 FM Receiver.

Our cars were parked next to each other and we powered up our GPS Units at the same time. My C340 had traffic data in 30 seconds. My friends Nuvi 660 did not display traffic data until about 3 minutes in. Our units were both mounted in the windshield.

My theory is the internal receiver in the 660 antenna does not pick up as well as the external antenna and it takes longer to lock on to the signal. The GTM 12 has a 3 foot wire antenna that I route up the A-Pillar and the end is attached to a small suction cup at the top of the windshield.

Anyway that's my theory. My buddy is a lit bit upset because he paid significantly more for his unit and his traffic data takes too long to be of use when he leaves our office.

Brott

Thanks for that experiment. That has to be the reason.

I wrote to the support for www.realtraffic.net and they responded that another person noted some spotty service.

The Acquisition time is another issue as has been revealed through this thread.

--

The company Clear Channel is behind the FM Traffic transmission.

I posed some questions but there are no responses from the Executive VP, Distribution Development

Where are the FM towers located?

Do I need to be near a tower or drive by a tower to activate?

The SiRF Star III chipset found in the newer Garmins has a superior advantage to locking on to satellite signals and particularly in weak areas. The difference between my old Garmin V and my new nuvi 350 is amazing.

Another thing to keep in mind is that satellite acquisition happens much faster is you are stationary. If you turn on the unit while already in motion, it just means it will take longer to sync up. How long it's been off also plays a part as well.

--
Joe Morris
http://joemorris.org

Same for mine - 4 minutes tops.

I usually have the traffic up and reviewed before the sat's are locked on.
I don't think I've waited more than two minutes for traffic or sat. Traffic is always first, and have never lost the traffic signal while driving in the dfw area.

Hi;
I have the C 340 and am very pleased with the unit. I am expecting the GTM 12 this week and just wondered how you set up your GTM in your auto.
Also I have read that the suction cups on the GTM are not very effective and maybe you have a solution for that as well.
Thanks for your help and I look forward to your reply.

Placement of the antenna is very important. Your car is metal and acts as a shield that blocks RF transmissions. If you hide the FM receiver antenna down below the dash or somewhere similar, it will not receive as strong of a signal as it does when placed high in the windshield. My Nuvi 370 locks on to traffic usually in less than 1 minute with the external 3 foot antenna in the window. My guess is units with a smaller antenna built in don't pick up the signal quite as well due to their much shorter antenna.

In response to lazhow's concern about the suction cups not sticking, the old trick of licking them (or providing a drop of water if licking them grosses you out) before putting them up helps a great deal. Mine has been in the windshield for many weeks without coming down. Just make sure the windshield is nice and clean before applying the suction cup.

The first unit I purchased was returned after it would take about 10 minutes to acquire a fix - I'm in Redondo Beach, CA. The replacement unit now locks in in about 1 - 3 minutes. It seems to vary by time of day.

I started with a SP330. It was very slow sometimes - 3-6 minutes to lock in. I moved to a SP550 which is very fast, usually instantaneous, to lock on.

My Nuvi 660 takes 1-2 minutes if I'm standing still and up to 5 minutes if I'm moving. The FM Traffic is usually running by the time the GPS is tracking. This is in the suburbs with mostly 1 story homes.

I have a G35 Sedan and I appreciate the info as to placing it high on the window.
Appreciate the directions .
Thanks again

On my 660, it is usually less than a minute standing still, maybe 3-5 moving.
And it is mounted in front of my tach, so the sky is completely obscured by the top of the dash. Never had a bit of problem.