ublox eva-7m issue

[Mike Fannin]

All, I started programming 40 plus years ago but have been away from it for sometime. I am catching up fairly quickly but having some issues supporting a particular hardware product (ublox EVA-7M). I am having issues trying to obtain a Fix. I am monitoring it with U-center and find that it identifies 12+ satellites 20+ db levels but I never get get a fix. I am using the UBX protocol.
Any suggestions will be very much appreciated.
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hmf

[Ttelmah]

The forum is really meant to be for CCS C problems.
However assuming you are intending to use CCS to talk to it in the future, you are aware of just how slow the initial fix may be, especially if you don't have the GNSS operating?.
If (for instance), where you are attempting to use the unit, has poor coverage for the GPS, and no network connectivity, a fix may be impossible. Unfortunately, comparing with something like a phone, which will already have an almanac will make you think that the unit is not working...

[Mike Fannin]

I understand. However, my neighbor has a GPS solution that delivers a Fix within 10-15 seconds. I figured if the unit can see 12+ Satellites at a level of 20+ dB's that I should be able to obtain a Fix. Therefore, I naturally figured that I must be doing something wrong. Just trying to identify if I may have implemented something wrong or not at all.
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hmf

[Ttelmah]

Point is that a unit that has been on and got a fix within perhaps 1000 miles, and several weeks ago, will have at least a partial almanac. A unit that has not been on, or has been shipped a few thousand miles, needs to load an almanac. It can take up to about 40 minutes to get an almanac if part of the sky is obstructed (20 minutes with a clear sky). The GNSS ability will load the almanac from the internet, if the unit is connecting to the internet. This is how phones and stuff can now get such a quick fix, but if this is not enabled, or it's not talking to a network, then it has to load the almanac the slow way....
These units are used on a lot of multicopters and the manufacturers normally recommend that you power the unit up in a field, and leave it to sit for half an hour or so, till the initial fix is achieved. After this the fix is almost immediate.
Now a neighbour's unit may have a totally different 'sky' to yours. Things like interference, or obstructions to the southern sky (assuming you are in the northern hemisphere the WAAS satellites are here), make a huge difference. Also how is the unit powered?. Noise on the supply can degrade performance massively. Is there anything obstructing the antenna?.