loosing lock on.

corsamel · 10-18-2004, 05:40 PM

I have the nice and cheap usb gps receiver from ebay and its starting to do my head in.

I've moved it around all over my car.. worked for a while on my dashboard the my lilliput started to prevent it from locking on to anything. Now its in the boot on my parcel shelf and its nearly working.

It locks on to 4-5 sats on average within several seconds but then again on averge looses its lock every now and then. Even when it has a clear view of the sky. Not brilliant when your trying to follow the route its giving to a destination.

How does every find there lock on situation in built up cities? Mines pretty hopeless, looses lock on every few seconds when i'm in Manchester city centre.

So solved the first problem of it getting a lock on, on start up.. but it just looses lock on quite frequently while driving.

wizardPC · 10-18-2004, 05:49 PM

I'm having the same problem on my production machine. I know its not the GPS unit because I can get (and keep) a lock with my laptop without any problems.

I have to say that its a software problem, most likely a driver issue because I have 3 navigation programs on the production machine. I have been trying to sort it out for the better part of 4 months now. I personally have a Deluo USB GPS.

corsamel · 10-19-2004, 05:06 PM

I would say its the opposite for me. Theres a small red led which flashes on my GPS receiver when it has a lock on and this stops flashing every time it looses lock on. So even with no software running it still stops flashing and looses lock when it has a clear view of the sky.

Anyone else got the cheap and cheerful (£35 - £45) gps receivers from ebay? Does anyone elses keep loosing lock on?

julz · 10-23-2004, 08:00 PM

yep check the sticker on the bottom, its prolly a 'BU-303'.

I just got one from Ebay the other day. Not the best reception, none at home even when im standing outside with the GPS connected to my laptop. Using Destinator driving home the other day it kept dropping out ('signal too low, check antenna' voice prompt) and would occasionally drop out completely ('GPS not found' voice prompt) meaning Destinator had lost seeing it and had to reconnect to it even tho windows still saw it.

corsamel · 10-24-2004, 05:49 AM

Quote: Originally Posted by julz

yep check the sticker on the bottom, its prolly a 'BU-303'.

I just got one from Ebay the other day. Not the best reception, none at home even when im standing outside with the GPS connected to my laptop. Using Destinator driving home the other day it kept dropping out ('signal too low, check antenna' voice prompt) and would occasionally drop out completely ('GPS not found' voice prompt) meaning Destinator had lost seeing it and had to reconnect to it even tho windows still saw it.

Just drove about 15miles from my gfs house on the motorway (full view of the sky) and it just lost lock after about 5mins. As I as going about 70mph it took another 5-10mins to get lock back on.

Doesn't make sense though as I have heard several people who have this usb gps from ebay and it works perfectly. I'm thinking may be there isn't enough power going to it so i'm going to give some external power to the usb 2.0 pcmcia card its running from. If that fails going to try yet another place to put the receiver, why can't it just work first time eh!!

I think the roof is the best place for it, the receiver seems to be waterproof, but just dont know how I will get the usb cable to it without drilling through my roof.

carpcnoobie · 10-24-2004, 07:03 AM

Have you placed it on something metal?? I'm noticing that with my BU-303, it REALLY likes having some sort of metal to sit on. Like the trunk lid, roof, even my door. Also, I've heard of 'problems' with the BU-303 and Destinator, but I woulnd't know first hand.

Skorpion · 10-24-2004, 07:52 AM

i have the bu-303, and i couldn't get any lock on any sats inside my car.

so i had to mount it on the roof, next to where the radio antenna comes out (which is where i fed the usb cable through too). and i get lock straight after returning from hibernation, and keep lock always. not sure how many sats i get though.

i use destinator3, and i drive a 1991 toyota corolla seca.

Bravellir · 10-24-2004, 08:01 AM

Are you using sirfr or nmea. I almost get rid of the problem by switching to sirf.
http://www.mp3car.com/vbulletin/show...&postcount=684

I also find that the actual orientation of the receiver helps. I couldnt find any logic on this, but,

When i rotate it to make the red led face foward it improved signel by one third.

My receiver ( BU-313 ) has a built in magnet in the bottom, I will try to put some metal base under it to check if the quality can be improved evem more.

iamag35man · 10-24-2004, 09:06 AM

The same thing is happening to me. I'm using the Earthmate USB Receiver. When I first put it in my car I put it in the front where the factory GPS antenna would have gone. It wouldn't lock on to anything. I guessed that it was getting interference from somewhere either from the Xenarc or the digital florescent display for the air conditioner. So I moved it to the rear deck. From there it works as you guys described. It will lock on for a while, then loose signal. It's random. I decided to put it on hold until after I installed my WiFi card. I put the WiFi antenna on the same rear deck and now the GPS receiver won't lock on to anything at all. I pulled the WiFi card out and then it works. My only other option for inside the car is to put the GPS receiver in the inside of the sunroof shade so it can see out the sunroof. Now I just have to pull the headliner out and run the cable. If that doesn't work. I might go down to the Honda or Mercedes dealer parts department and pick up one of their external roof GPS antenna covers and mount my Earthmate inside that either on the roof or the trunk lid.

corsamel · 10-24-2004, 12:12 PM

Just had it on my roof and I almost keep the lock on through out my jouney, however going anywhere near a built up area with tall buildings it looses lock frequently which is a bit crap.

carpcnoobie · 10-24-2004, 01:49 PM

I had mine on the roof as well and occasionally lost signal for a short period of time when I was driving in Manhattan. But then again, I wasn't terribly surprised nor did I ever lose my way. The lock came right back and I navigated my way thru NYC.

fishy · 10-24-2004, 11:34 PM

hi all,

my findings with the BU-303 models are that they respond REALLY well to a metal surface underneath, hence the quite strong magnet inbuilt, which helps its inbuilt "active" antenna.

also, if an aircraft flys overhead, this can cause a signal loss thanks too the planes "rad-out" system, which sends radio waves to the earth, that bounce back to the aircraft in order to calculate its own alt. etc etc.

note - not all aircraft have these, just major planes like Boeing, Airbus etc.

also - this radar unit in aircraft is extremely powerful, if it is fully charged (IE in operation) and you walk directly under it while an aircraft is using the radar you will no doubt get cancer, and prolly microwave your insides

this can cause the BU-303 models to drop out, due too all the interferance.

major aircraft use this when in flight, IE after climbing to altitude or before decent, so if you have aircraft flying overhead, dont expect the same performance from your BU-303 model...

just my observations.

aarroyo · 10-26-2004, 04:16 PM

I alos have a BU-303 from Ebay. Placement is very important in locking in. I have noticed that the magnet facing down, on top of my truck works the best. I have had it on my windshield, by rear window, my side windows, mounted verticle, under glass etc. A glass between the reciever and the sky can be a difference between locking in on 4 sats or 8 sats in the same spot. I plan to locate mine outside on top of my truck. I hope it is water / weather proof.

Bravellir · 10-26-2004, 04:53 PM

The one I have, from navilock, i asked them and they said that it's not water proof

corsamel · 10-26-2004, 07:02 PM

Can't really see them designing it with a magnet.. as this is surely meant to be stuck on the car roof, think they are water proof!

Mines on the roof now and i'm still loosing lock ever so often which is really annoying.

hows does everyones perform in a built up area? for example do you loose lock (even for a couple of seconds) every 1min? 10min? 30min?