CD Player interferes with GPS
Submitted: Monday, Aug 29, 2005 at 19:23
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Erwin
I have my GPS mounted on the left side of the steering column between the steering column and the radio/CD player in my 2003 Hilux. I just noticed on my last trip that when I play a CD it interferes with my GPS in that it drops the satellites right out and gives out very false readings eg. Max Speed 275kph. (Hiluxes are good but they are not ferrari's.)
I took the GPS off the mount in put it on the far right of the windscreen dash but it made no difference.
Has anyone else had a similar experience. It is only affected by the CD player, not the radio. I have a combined CD/MP3/Radio system. Would an external aerial make any difference.
I get geath coverage where it is mounted and would prefer not to have an external aerial.
Reply By: Notso - Monday, Aug 29, 2005 at 19:30
Monday, Aug 29, 2005 at 19:30
Yep, same thing happens with the Nissan Patrol. I reckon there is rf radiation emitted by the CD Player that is close to the frequency that the GPS system uses.
Haven't tried this but if you need to play CDs while you are using the gps, maybe an earthed metal plate between the CD and the GPS might help.
Good luck!
AnswerID:
127345
Reply By: arthurking83 - Monday, Aug 29, 2005 at 21:08
Monday, Aug 29, 2005 at 21:08
RF interference at 1.5GHz! from a CD player??
I never heard of such a thing!
AnswerID:
127360
Follow Up By: arthurking83 - Monday, Aug 29, 2005 at 21:15
Monday, Aug 29, 2005 at 21:15
Is it a Garmin?
You could try adding a choke over the power cable of the GPS!!
( you can buy chokes from
places like Jaycar or Dick Smiths......)
FollowupID:
381862
Reply By: AdrianLR - Monday, Aug 29, 2005 at 22:18
Monday, Aug 29, 2005 at 22:18
There are reports of this from people who have mini LCD monitors. I haven't come across a definitive explanation and it's certainly not a "primary" frequency (eg 44.1kHz CD sampling) that's causing the problem but may be a harmonic from some source - a sort of electrically "dirty" noise. The real solution always seems to be "mount an aerial outside the car". You obviously can't completely shield the GPS unit and can only partially shield the CD player (gets a bit inconvenient if there's a sheet of aluminium covering the front!)
If the CD system is new perhaps an option would be to exchange it for a different make (even paying extra may come out at the same as an external antenna)
Adrian
AnswerID:
127378
Reply By: arthurking83 - Monday, Aug 29, 2005 at 23:01
Monday, Aug 29, 2005 at 23:01
I have read that a computer can cause EMI interference with a GPSr if the reciever is in close proximity. This is due to the high clock frequency, in the GHz ranges!
There may be circiutry in the CD player that causes interference in the power lines??
I'm no electronics expert (my any stretch of the imagination!)
But I do have lots of ferrite chokes on the cables of my DVcamcorder, because apparently they are susceptible to EMI or RF interference!
Other than that........???? :/
AnswerID:
127380
Reply By: joc45 - Tuesday, Aug 30, 2005 at 00:14
Tuesday, Aug 30, 2005 at 00:14
Hi Erwin,
I have no problems with playing CDs in my Series I GU Patrol affecting my Garmin GPSII+.
Rather than interference at 1.5GHz, I tend to suspect interference from the CD player is getting across at a lower intermediate frequency of the GPS, or into its CPU if the internals of the GPS are not screened.
I tend to dismiss the DC feed as the culprit, tho there would be no harm in trying a DC filter on the 12v feed to the GPS (the type used on power feeds to car stereos).
If the GPS is connected to a laptop, this may be causing some form of earth loop problem. The filter may fix this.
Good luck,
Gerry
AnswerID:
127387
Reply By: Erwin - Tuesday, Aug 30, 2005 at 04:33
Tuesday, Aug 30, 2005 at 04:33
Thanks for the replies. It took me a while to work out what was going on. I had a 16 hour trip in front of me and it took the best part of the first 30 minutes to isolate it to the CD player.
I'm going to try the GPS unit in other vehicles with a CD player and then another GPS unit in my vehicle.
Will let you know if I come up with any answers.
Thanks
AnswerID:
127392
Follow Up By: Nudenut - Tuesday, Aug 30, 2005 at 07:44
Tuesday, Aug 30, 2005 at 07:44
is the gps affected when running on its own batteries or different power source?...if so try what others have said, install a filter/choke.
FollowupID:
381891
Reply By: Banjo - Tuesday, Aug 30, 2005 at 09:13
Tuesday, Aug 30, 2005 at 09:13
My Magellan randomly did a similar thing inasmuch as the speed wobbled all over the place and the breadcrumbs zig-zagged wildly. I could never find out what caused it as it was, as stated, random. Would go crazy for 5-10 minutes and then return to normal. Didn't happen often so didn't track down the cause. Didn't have a CD player so wasn't that. Maybe UFO's?
Banjo (WA)
AnswerID:
127405