gps receiver not locking
-
@Dana-Myers114 I may have had a breakthrough with the GPS sensitivity issue. In the course of tinkering with my GPS receivers (removing the antennas, inspecting them, etc.) I found that sensitivity appears to be restored if you re-route the coax pigtail from the antenna so that it's not over the PCB:
This appears to reliably fix every one of my 3 GPS EXPs. I did desolder/resolver the antenna in each case before discovering this, but I don't think that's necessary - I think you may be able to fix your GPS by removing the pigtail from the U.FL connector on the PCB, re-route it, and replace it on the U.FL.
If you can try this and report back, I'm curious to hear how it works for you.
(I think this has to do with the cable/connector being too close to the input component on the PCB but that's speculation).
Dana
-
Dana, i tried that first thing after disconnecting the cable thinking that it might be a poor connection from the factory and having the pigtail like your picture did not help my situation. however your remark about doing a repair to the connector solder joints makes me think that once i get my other omega2+ in the mail later this month that i will give that a try as there could just be a problem with the soldered connection. for now, having a larger antenna solves the signal issue for me but creates an issue of not having a good place for the larger antenna.
-
@Douglas-Kryder the other thing I did that may be notable, after desoldering the antenna from the PCB, is clearing excess solder from the antenna left over from when it was originally soldered to the PCB. In particular, one corner of the LNA shield (on the bottom of the antenna) is cut-away, but when it was soldered to the PCB, this corner was filled with solder and shorted to a pad/via on the LNA board. I cleared that on all of my 3 GPS Exps as part of the R&R and did not re-fill it when re-mounting the antenna. Given the shield is cut-away there, I believe it's not meant to short to the pad and this may be deafening the LNA.
-
Nice! Something to test and hoping it works for some but for me, at least, it seems it's still not locking properly in the u-Center app as well others.
I have a new antenna coming in that has some distance in hopes that will resolve the issue within days. I did try your re-route of the connector wire but alas; it didn't lock. What it did do, however, is seem to increase the signals that I do get compared to them when the connector wire is across the board, lol.. Getting there
-
@Dana-Myers114 Thanks for the tip, desoldering and re-soldering did the trick, mine also had a solder blob where shouldn't be. It's now working fine.
-
@Dana-Myers114 said in gps receiver not locking:
@Douglas-Kryder the other thing I did that may be notable, after desoldering the antenna from the PCB, is clearing excess solder from the antenna left over from when it was originally soldered to the PCB. In particular, one corner of the LNA shield (on the bottom of the antenna) is cut-away, but when it was soldered to the PCB, this corner was filled with solder and shorted to a pad/via on the LNA board. I cleared that on all of my 3 GPS Exps as part of the R&R and did not re-fill it when re-mounting the antenna. Given the shield is cut-away there, I believe it's not meant to short to the pad and this may be deafening the LNA.
thank you. i'll look for that on mine when i do the de-solder/solder work.
-
@Endre-Czirbesz said in gps receiver not locking:
@Dana-Myers114 Thanks for the tip, desoldering and re-soldering did the trick, mine also had a solder blob where shouldn't be. It's now working fine.
That's 2 now, with an desolder and re-solder, seemingly working well so I think I'll try mine soon. Just visually the antenna on mine is crooked and seems 'blobbed' as well so hoping once I get the chance, I'll see if mine also helps.
Thank you all!
-
Does anyone have a photo or better description of where the blob is?
-
As more confirmation.. Before I unsolder and resolder this ceramic antenna I wanted to first try a suitable external antenna I picked up off fleaBay.
I had an SMA to uFL connector bridge from some other MCU antenna's for WiFi so I just picked up an Active 28db antenna that ran me about $8 usd and as soon as I plugged it in within seconds it had both a 2D and 3D fix with accurate data.
Now that I know the u-blox MCU works; it must be something with the built in antenna and the soldering, as others have found out. I might get some time to desolder and resolder the ceramic one or just use the external for now.
Something's up with the Omega antenna on how it's placed, affixed or logic on board before antenna (ie: that missing or removed cap)
Thanks for everyone!
~Icky
-
I had a reply to my ticket now. It confirms that the removed cap is already missing from my board.
-
I desoldered the antenna and removed the excess blobs, and just tac-soldered it back down.
It locks reliably using usb and ublox u-centre, but switching to the Omega2+ and putting it in exactly the same position it can "see" 2-6 satellites (varies widely) and never locks position.
A previous post said the GPS expansion on an original Omega never locked and it was put down to interference from the omega and dock itself. I'm beginning to think this is still true on the Omega2. Moving the antenna away from the omega makes it work
-
With the latest update to ogps I am now able to lock onto a satellite.
UPDATE: Unfortunately I only managed to lock onto a GPS once.
-
Months passed and still no solution... unable to lock
.
-
I think the issue is either software related or hardware specific to the Omega dock. If I connect the GPS expansion to a Raspberry Pi I can lock onto a satellite.
-
nothing nothing
...I see new products but nothing about the "old" bugged products (GPS)? An answer ? A correction? A replacement? ???
It's not serious! Is there a sales manager here? A technician?
