Lag on Kenwood DNX5220BT, Normal

the_big_1 · Occasional Visitor Joined: Jul 04, 2006 Posts: 40

Hi All,

I have noticed the car position on the map appears to be 100 - 250 yards behind the actual car position and some times the map freezes a little or it shows the car almost spinning on the spot. Is this normal?

Border_Collie · Posted: Tue Jan 06, 2009 9:53 pm Post subject:

Have you lots of POI's showing on the map? If so turn them off and you should see an improvement.

Car spinning on the spot is usually because of weak or insufficient signals.
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the_big_1 · Occasional Visitor Joined: Jul 04, 2006 Posts: 40

Even when its zoomed in and no POI are showing, its still the same. It was OK until the last couple of days.

Border_Collie · Posted: Tue Jan 06, 2009 10:12 pm Post subject:

Probably not get a good lock on 4 sats or losing them momentarily, once gone they can take a while to lock on again if you are moving.

I had similar with mine some time back where not only was I doing a 'break-dance' every time I stopped but it was giving totally wrong directions as it thought I was elsewhere. A soft re-set cured it for me.

Next time it happens have a quick look at signal strength/ locked sats.
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the_big_1 · Occasional Visitor Joined: Jul 04, 2006 Posts: 40

This morning, once I was on open road and switched on the ground gps thing and routed, it was fine but it kept coming up with "No GPS Diff"" or something. I turned off the ground GPS and the message went but once I got in to town, the lag came back.
Would the extrnal antena being upside down cause a problem?
As for sat loc, when I could see them, because of driving, all but two bars where greeen.

philpugh · Posted: Wed Jan 07, 2009 3:09 pm Post subject:

'Break-dancing' when you are stopped is usually down to a poor fix. This could be because of a limited number of sats visible - or that all sats you are 'locked' to are in one small area of the sky due to blocking etc.

A small amount of lag is to be expected. The last position fix can be a second or so behind your 'real' position plus processing and map re-drawing delays.

Lag on my nuvi 660 was about 20-50yds when not following a route and within 10yds when following a route. When not following a route there was a very short delay when coming to a junction as the logic worked out which road I was on.

Although new (to me) with the TT 720 I have not noticed this behaviour as much - although when not route following it does lag behind a short distance due to delays - i.e. when I stop it gets the correct position very shortly after (a few screen refreshes and subjectively less than one second).

Antennae position can affect reception - but having it upside-down shouldn't be too much of a problem unless there is a metal plate on the base of antennae which could reduce the signal. In an open evironment (e.g. out of town) I would expect you should get a good signal on 9+ sats.

Does this product use the GARMIN XT software (this is just out of pure curiosity!)
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the_big_1 · Occasional Visitor Joined: Jul 04, 2006 Posts: 40

The Antenna has a magnetic base and at the moment, that is facing up.
Not sure on the software, it does look like Garmin PC but no real idea.

philpugh · Posted: Thu Jan 08, 2009 10:43 am Post subject:

Can you can get the antennae the 'right' way around - even temporarily - and see how this affects reception? Park the car up and with it (that's the antennae!) upside-down monitor the sat numbers and strength (just roughly) for a minute. Then move the antennae and repeat. The signal levels are always changing small amounts in any event. Doing this may help you find the 'best' position for the antennae.
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the_big_1 · Occasional Visitor Joined: Jul 04, 2006 Posts: 40

Will try it at the weekend, its easy to do as the antenna is fixed with speacial tape to the roof loading bay hatch

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