FM Transmitter - Nuvi 660

From what I can see of both units (Scosche and Audiovox) I am not convinced that either is designed to be the wireless solution I have in mind. Both seem to have a lead that has to be hard wired to the Nuvi (or whatever they were designed for).

From the AudioVox image it clearly shows a lead that is labeled 'to XM radio' and has a plug on the end. The Crutchfield web site description has two lines that appear to confirm that this is not a 'wireless' solution.
1. "The FM Direct adapter is used to DIRECTLY connect your XM receiver to your car's audio system and antenna.".
2. "To XM Radio: The adapter has a 6' antenna lead with a single SMB connector that plugs into your XM receiver's antenna input.".
This is a link to the installation manual for this device that confirms the hardwire to the device is necessary... http://akamaipix.crutchfield.com/Manuals/220/220XMFM1.PDF

I'm still very intrigued by why this unit works so well for Joel in his application though.

The Scosche unit appears to be an FM transmitter that would have to be connected (with the 3.5mm plug) to the line-out on the Nuvi receiver itself. If this unit could be plugged into the Nuvi cradle then I would agree that this would be a fine solution (subject to the power of the FM transmitter).

I guess I'm still searching for my holy grail.

Then most likely your problem is the cassette deck itself. If a good cleaning didn't help, then it's probably just nearing the end of its useful life.

Curious, the only thing I can think of here is that the lead from the AudioVox unit to the XM cradle acts as an antenna (presumably not designed for this and not sure why it would as the cable would be shielded) that the Nuvi's FM signal is picked up by.

Just a thought!?!?

Interesting. Might be that the antenna lead going from the car's radio to the point at which you unscrewed the antenna from the fender is functioning as a close-range antenna, picking up only the FM signal from the nuvi but not allowing in any FM stations to interfere. Just a guess.

Not an ideal solution for me, however, because I would like to be able to listen to the radio when not using the nuvi.

Interesting thought. However I don't see how the lead that goes to the XM cradle could be used as an antenna when the XMFM1 is in "OFF" mode. It would seem that when the XMFM1 is off, the signal from that lead is also off, and the vehicle antenna is allowed to pass-through to the radio.

From the Audiovox manual that kruckley posted:

With the ignition on, the FM Direct Adapter is always on in a standby condition. When you turn on your XM radio receiver, the adapter will automatically switch the vehicle FM signal input from your FM antenna to the XM audio signal.

It sounds like the XMFM1 gets both it's power and the audio from the XM receiver via that 6' lead that connects to the XM receiver dock. And apparently there is some power going through that lead to the XMFM1 whenever the ignition is on, even when the XM radio is off.

Paintball says it works with the nuvi when the XM radio is off. So perhaps whatever the XMFM1 is doing when it's in "standby" mode is what's making it work.

It still doesn't make any sense to me though, because if when the XM radio is OFF, the XMFM1 is also "off" (or in "standby" mode), it is just allowing the vehicle's radio antenna to pass straight through to the vehicle's radio. How does that in any way improve the chance of the nuvi signal getting to the car's radio without interference from radio stations?

My 660 (ver 2.40) has choices for...

2.0mW
1.0mW
0.5mW

But there is also a box called 'High Pwr' that is selected. I assume that means use the highest power that it can.

Considering the many reports on this board (and others) that the FM transmitters for ipods etc. work much better than the Nuvi's I would guess that the Nuvi transmission power is not close to violating

Where do I change this power setting. I can not find it on my 660.

That's the Million Dollar Question, you can't change it with the 240 file... Lets hope future updates will let you....

I can tap on the 2.0 in the menu and can hear the hissing disappear. But regrettably it doesn't save when you shut it off and turn it back on. The only way to get out of that menu. If there was a way to change the settings and save it as default, that would be great. But I don't see a way.

Well, I've given this discussion about all I can, so I'll leave it to ya....... The audiovox works great for me (with the 750 FM transmitter on and the XM radio OFF).

Cheers ya'll.........

Joel

A battery powered transmitter may work better. I switch vehicle daily and have found that I can not use a transmitter powered from the cigateete lighter. The cigarette lighter power is not "clean" it feeds back from various bearings or other ground side static. A battery powered transmitter has it's own ground and will not give you these problems.

so I posted that 4 times by accident, so it's true most of your issues are ground side and you can eliminate that entirely with your own ground ie batteries. You can filter your power or antena till you retarded, but it will not replace a "clean" ground. The only substitute might be the same filtered/clean ground for the stereo uses, you could probalby tap that at some point..

maybe at the fuse box

The sound is great.

Many thanks for your input and your experiences with your AudioVox. I'm tempted to buy one just to see if I can get it to work without a hard wire.

I'm starting to think though that there is no easy resolution to this issue. I've just broken down and ordered a cable to wire Nuvi line out directly to my car radio Aux in I guess with this at least I'll get a better bandwidth and the MP3's should sound much better.

I just can't believe that this is true. Why wold Nuvi go to the trouble of having these screens available with the select boxes if you can't exit out and save your settings. I'm fairly sure that there are some tier one (or higher) Nuvi techs that know exactly how to do it but are told, under pain of death, never to pass on how to do it to the general public.

To be honest it doesn't make any sense to me either. I absolutely want to find a solution to the FM transmitter that does NOT involve hard wiring the Nuvi (I'm fine with adding another cable to the Nuvi cradle though). Maybe for the low cost of the AudioVox I'll give it a go (take one for the team).

Kevin

I'm also curious why would a premium company like Garmin spent resources to design a diagnostic screen with selection options would not let selections to be saved. If the selections can be saved, some of Nuvi 660 issues would have been resolved. Why is it so secretive? Why? Why? Will someone from Garmin address these questions for its customers?

I'm always using my Nuvi 660 fm. There is no major problems while using my unit's fm transmitter. Yes, sometimes there are signal interference but it is not too bad. I wonder, does it depend on the location?! For example, today for a two hours trip accross my city (Calgary), passing through down town, I noticed a couple of interfereces that lasted one to two seconds.

Anyway, I'll stick to my Nuvi 660 fm transmitter as long as it won't give me a hard time.

Thanks for the suggestion.

Another advantage of a battery powered FM transmitter is that some are very compact and could be attached in a location near to the nuvi so that a wire doesn't have to be run all the way down to where ever the cigarette lighter power ports are. Plus it frees up a power port.

Try to use car adapter with FM transmitter as it will get the strongest signal to it

Has anyone received any kind of explaination from Garmin about the poor fm? This feature was a key selling point for me, and I'm pretty disappointed in the performance.

I think everyone's FM isn't the greatest. It is difficult to make it 100%. I am fortunate enough to have an auxiliary input in my stereo of my car. Honda did a great job as I never thought I would use it hahaha.

It is hard to do FM wirelessly. It works OK without being connected but it works great when I hook it into the auxiliary.

I know there are some decent work arounds. But, I've used other fm devices that work just fine. Can't imagine why Garmin would let this product out the door with this level of performance.

bwarden;
After hours of messing with it, I'm leaning toward your diagnostic conclusion: the cassette deck is nearing the end of its useful life. Dang, I seldom use it, it still dies.

Some newer cars have an auxiliary input built in. Check your car's manual to see if you have one. If you do, you can simply go to Radioshack and buy a minijack to minijack cable to connect your garmin to the aux input.

I have an mp3 player which I use in the car, so I've been following this discussion mostly out of curiosity. Then I decided to try my Nüvi 660 playing the mp3s through the FM transmitter.

I have the 660 set to 88.1 (seems best for my area) and my car has the antenna in the rear window. So far it has been working fine. What I especially like is being able to use my phone via bluetooth without the need to mute the sound.

My radio allows for the selection of FM1 and FM2, each having 5 presets. I set the FM2 to 88.1 (660) and 107.7 (XM), alternating the presets, making it easy to switch between the two.

I notice it on mine when I am at certain intersections and I am waiting for a stop light. Not sure what is going on at an intersection but I do notice it at the same intersections.

I've noticed it also. I think it may have something to do with the controller for the traffic light. Also, it seems the FM signal can be "adjusted" slightly by changing the angle of the Nüvi antenna.

Living in the NYC Metro area. The FM transmitter is pretty useless. It it wasn't for the Traffic updates I would have purchased the 650

No kidding. With all the stations you have up there, there really isn't a spare FM station. I live near Dallas, and there isn't much free space here either.

That's why I run it through the MP3 input of my car stereo.

So I decided to give it a go and removed (unscrewed from the front fender) my car radio antenna.

Well, it is certainly an improvement as far as being able to get a clearer sound from the nuvi FM transmitter. Sound quality is about on par with a somewhat weak FM station, and there is still a tiny bit of background static (which you can only really hear if you have the volume turned up loud when there is no audio coming from the nuvi). But the main improvement is the quality of the sound is consistent rather than varying depending on your location.

The quality of the sound through my cassette adapter always sounds terrible so this is at least as good as that. Obviously the drawback is I can't listen to the radio.

I'll say that it is a good work around for now as I'm probably getting a new car soon and don't want to bother with replacing the HU or wiring up an FM modulator.

I have been playing around with my 760 and the FM transmitter for a couple of weeks now. I could be wrong but it appears the devices are using the Nuvi power cord as the transmitting antenna. I use a bean bag mount on the dash of my vehicle. If I leave the power cord hanging down from there I receive tons of static and the FM transmittier is worthless. If I loop the power cord around the rear view mirror post however the reception is darn near perfect. As others have mentioned, placement of the power cord could make a huge difference. Give it a try.

I think you might be right about this. I have ordered a spare power cord with the intention of trying to identify which wire this is. If I can identify it then I will try to splice it (directly or with a 1:1 isolation transformer) to the car radio antenna cable.

Failing that, I have also ordered this.. ( http://www.crutchfield.com/S-JHxWmVQ471I/App/Product/Item/Ma... ) that I will either splice into my existing radio antenna or replace it entirely with. I will place the active 'pickup' part of this antenna either very close to the Nuvi (on the back of the cradle?) or very close to the Nuvi power cable in the hope that it will get MUCH better reception from the Nuvi transmitter.

kruckley,

Let us know if that works.

I have the excess slack of my GMT-20 power cord coiled up and tucked into a cubbie near the power port.

Do you think the GMT-20 cord is both a transmitting antenna for the FM transmitter and a receiving antenna for FM traffic?

I will update everyone as soon as it gets here (anxiously waiting!).

I do think that the power cord is the antenna for the FM transmitter (and the FM traffic receiver). There are clues in the owners manual that suggest this and also other threads I've read and research I've done seem to confirm it.

Kevin

I would strongly suggest an FM transmitter. I use one on my Toyota Camry and Lincoln Navigator.

Other option = moving closer to antenna. Remember, some cars have the antenna built in to the rear window, etc. Moving it closer to the radio isn't going to get you closer to the antenna unless you use the FM transmitter that connects to the back of the radio. They're REAL easy to install though.

Traffic yes - FM transmitter no. I get the same results with or without the power cord (using the device on battery). But, then again, I do have the Audiovox device I listed WAY BACK in this thread.

Joel

This sentence from page 36 of my Nuvi manual suggests that the 12 volt adapter plays a role...

"The distance between the 12-Volt adapter, the nuvi, and the FM stereo antenna may also affect the noise level."

If the Nuvi FM transmitter antenna was located inside the Nuvi case ONLY and did not extend externally then the location of the 12 volt adapter would be irrelevant, also the effective radiated transmit range would be insanely small (I know the argument is that this is the case!).

Even in Belkin (and other) FM transmitters for ipods etc. the lead to the cigarette lighter adapter is used as the antenna unless it is fitted with a separate lead.

There are also other threads (here and other forums) where speculation is that the antenna is within the power cable.

Hoping you're wrong but quite prepared to find you're right

Re-read the manual, and of course, you are correct. All I know is the results I get, and forgive me for sharing them in an unabashed way. Mine works as well plugged in as it does free from the DC connection. I'm beginning to believe that I have a freak of nature (or man) here.....(OR - could it be the Audiovox device?).......hmmmmm.

Joel

If the unit is using the power cord as an antenna, it should't matter if it's plugged in to the 12v source, only that the cord is plugged in to the Nuvi.

I had a Nuvi 660 with hardly any power out. I also had a problem with the Currency Exchange. I return mine to the dealer and got another one. This one has a much, much better transmission.

The audio installer at my Circuit City is going to install this unit, AXXESS AIP-TY02, to my truck tomorrow. This plugs into the back of the radio into the external multi-CD changer. Has the Ipod 8 pin adapter but also has the mini media jack. The instructions say you can plug any device with a mini media earphone jack into the plug and it will use the radio. I plan to plug my SanDisk Sansa or my Nuvi 660 into this jack while traveling. It cost $48 US at CC, but cheaper on the net.Installation cost run from 33 to 50 dollars depending on the car. Anyone interested in the outcome, I will post it here.

what's the difference between headphone and line-out setting?

The eastiest work around for the POOR FM transmitter is to attach a set of head phones (ear buds) to the audio out jack top left side of the NUVI.

Let them lay across the dash or better yet clip the loose end (ear buds) to the sun visor.
The head phones will act as an antenna and amplify the signal considerably, on my signal strength meter at an 8 foot distance the signal strength goes from a unusable 2 to a good 10 on the meter scale. Solved my problem, make sure you have the volume set to 100% this also increases the signal and reduces the noise. The signal increase is not as great if you are useing the cars DC power or a traffic adaptor.

Let me know if this works for you.

When you say the XM has to be off, are you just saying to maximize the clarity of the direction announcements on the Nuvi, or to use the nuvi at all. I only ask because I am able to use my XM while I receive traffic on my nuvi using the FM transmitter.

Since I'm using the same frequency for both the XM and the Nuvi, one of the two has to be off (or in the case of the Nuvi, not using the FM transmitter). I don't know how you are doing what you are doing, because my Nuvi will not overpower the XM radio transmitter. Consequently, if I have the XM on, and turn on the Nuvi Transmitter, all I get is XM - no instructions, and no MP3 music.

Joel

I took my Nuvi-660 to my car-stereo guy, who owns the Car Stereo Plus shop (who has been an installer himself for 32-yrs) to see about using an XM FM1 to improve the Nuvi's FM-transmitter.

Since there is NO place to plug the XM FM1 into the Nuvi, because the jack is the wrong size, we tried placing the XM FM1's jack-lead (which is supposed to plug into an XM-radio, and most likely IS shielded anyway) right next to the Nuvi hoping for it to pick up the Nuvi's FM-signal, and then we even wrapped the lead round & round the Nuvi, just to be sure. Several attempts at several tests resulted in NO improvement what-so-ever.

What finally worked, was to take a short cable with a earphone-jack at one end, and two RCA-jacks at the other end, and patch the Nuvi directly into an audio-input in the rear of the stereo head-unit.

So... now I have a wire which comes out from under the dash, and I have to plug it into the earphone-jack of my Nuvi. Plugging into my Nuvi was unavoidable... but works quite well-

I too was hoping to avoid plugging wires into my Nuvi, but at least I have a good working GPS-audio to car-stereo relationship now.

has anyone else tried this, and how did it work for you?

What other resources or techniques have others had success with?

--What works for one... may not necessarily work for another-

I'm still wondering how this worked for Joel. This subject intrigues me. We tried this very same thing to no avail. I'm pretty sure it works as he says it does, but as he also said --it just may have been some kind of a freak of nature indeed-

~Jim~

This is the best solution anyway. If I had RCA inputs available on my head-unit I would do it this way. The only reason I'm playing around with the FM-transmitter is because my factory Chrysler stereo doesn't have those inputs and the cassette deck doesn't always play nice with cassette adapters either (you have to fiddle with the adapter to get it into just the right spot where the heads line up correctly).