GTM 20 FM TMC Traffic Receiver Performance

 

As a relatively new nuvi 760 owner, I'm not sure what to expect with regard to performance of the FM traffic service. According to the coverage map, I have been well within the "green zone" north of Baltimore, yet have mixed results . At times the signal locks in (green led on the receiver) and traffic information is readily available and quite helpful. At other times - and I have noticed this on the past two short trips on I-95 and Route 40, the led is yellow and the no traffic data available message is all I get under the traffic menu option. Strangely enough, bringing the unit into the house and testing from inside the house, running on internal battery power, I have been able to get traffic data after getting nothing within the vehicle.

Maybe I am I missing something obvious, but is this typical performance? Any suggestions?

Thanks...

Similar performance in Chicagoland

I live about 40 miles west of downtown Chicago and commute daily about 25 miles towards the downtown. I never get reception at home, the LED is red. Usually about 10 miles into the commute, the LED turns green. So I'm guessing that the reception range is 25-30 miles. Seems kind of strange that I can receive FM music stations much farther away but not the FM traffic. Of course, the car has an FM antenna and the GTM-20 "antenna" is built into the cord. The cord is mostly below the dash level. I tried looping the cord over the mirror, and reception improved. But I'n not going to drive that way. Too bad there's not some sort of way to connect the GTM-20 antenna to the radio's FM antenna for better reception. Once I get reception, it will show traffic data for points that are 60 miles away. What good is that if you have to be 30 miles from the transmitter to get reception?

On the drive home at night, I notice that it takes 5-10 minutes to get the traffic data going. My office is only 1 mile from the expressway, so if I take off right away, I'm already on the expressway by the time I get my first traffic alert. So I wait a couple minutes before I get on. I have about a 50/50 chance it will warn me of a delay - there's lots of construction in the area and sometimes the delays are reported to be 30 minutes or more. The "Avoid" feature works quite well when there's an alert.

Once I get reception, it works pretty good. I just wish there was a way to hack the hardware a little to improve the reception distance.

RMA

After troubleshooting the GTM 20 performance, the customer service representative at Garmin that I worked with provided an RMA number for returning the antenna so that I could try a replacement. I have my doubts about whether that will make any difference with reception, but I am planning to give it a shot. The fact that the customer service rep did not think the antenna would work unless connected to power does not give me a warm and fuzzy.

Reception

I live in Beaumont, Texas and am about 90 miles from Houston and I receive their traffic reports. Never thought it would reach that far.

MSN Receiver Just Expired on my 680 and...

I have been thinking about renewing my subscription for over 2 weeks now, but have not, yet.

Reading about the GTM 20 here makes me wonder what service is reliable enough to pay money for. My MSN is better now than it was a year ago, but still not dependable. $5 per month for maybe seems like a bad deal. Sounds like the GTM 20 is the same. Unfortunate.

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Frank (Nuvi 2497LMT, 2455LMT, 765LMT,680,StreetPilot 2720)

How is the traffic performance in the DC/Baltimore areaa?

I have heard mixed reviews re: the clear channel traffic service. Most say that the performace depnds on the region- some regions have too much a delay in the traffic reporting for it to be useful (e.g. by the time it is reported, it is alreay too late and the disruption is cleared.

Any reports on how the traffic alerts are fo rthe Balitmore Are? The DC area? Points in between?

Thanks

try the trial period

If you have the opportunity for the free three month trial...use it.

It does depend on your locale. In and around the Dallas/Fort Worth area it works for me. I live 40 miles from Fort Worth and I get reception, in my garage with the doors closed. My C550 is not kept on the dash or windshield. I keep it down low, forward of the center console. Sat and TMC reception are constant. When I travel out of reception range, such as between Ft Worth and Austin...well I don't have traffic coverage. When I get close to Austin, it all kicks in again. It works for me, it's not perfect and sometimes not even great, but overall I'll keep it.
Here is a TMC station list. I'm guessing if you can pick up these stations near your location, you should be able to pick up the TMC signal as well.

http://www.realtimetraffic.net/StationList.pdf

it's from the "links" from

http://realtimetraffic.net/ which is from the garmin page
http://www8.garmin.com/traffic/fm/index.jsp

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........Garmin StreetPilot c550 / Nüvi 765...........

No issue in SFO

I tried mine in San Francisco and had no problem.

traffic receiver

I fought weak signals with my FM traffic receiver for many months finally contacted Garmiin and found it was a bad GTM20 If you are having short range i think the exchange will take care fo the problem.

I live 40 miles north of houston and the transmitter is on the south side of Houston so I thought it was a range problem. The coverage range s great if the GTM 20 is good.

Same with 660

java007 wrote:

As a relatively new nuvi 760 owner, I'm not sure what to expect with regard to performance of the FM traffic service. According to the coverage map, I have been well within the "green zone" north of Baltimore, yet have mixed results . At times the signal locks in (green led on the receiver) and traffic information is readily available and quite helpful. At other times - and I have noticed this on the past two short trips on I-95 and Route 40, the led is yellow and the no traffic data available message is all I get under the traffic menu option. Strangely enough, bringing the unit into the house and testing from inside the house, running on internal battery power, I have been able to get traffic data after getting nothing within the vehicle.

Maybe I am I missing something obvious, but is this typical performance? Any suggestions?

Thanks...

I haven't tested mine in the house but I am seeing a lot of lag before traffic comes up after leaving my house in Ellicott City in the mornings. Sometimes it takes as much as 15 minutes, which is really annoying because I can't tell if it is safe to get on 70 or not!

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-- Garmin 660 Ellicott City, MD

Baltimore traffic pretty crummy

eh20814 wrote:

I have heard mixed reviews re: the clear channel traffic service. Most say that the performace depnds on the region- some regions have too much a delay in the traffic reporting for it to be useful (e.g. by the time it is reported, it is alreay too late and the disruption is cleared.

Any reports on how the traffic alerts are fo rthe Balitmore Are? The DC area? Points in between?

Thanks

That's been my experience in Baltimore. An incident has to be pretty bad for it to be still in place when Clear Channel reports it.

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-- Garmin 660 Ellicott City, MD