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I have seen this but never did figure out why it does it. I have some that show lock and some that don't. ?I'm looking forward to hearing the responses.
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Wasn't this already discussed ? If I'm not mistaken there's some discrepancy with the GPS data checksum on some units (or settings in the gps) , the workaround/solution is to disable the gps check (=0) parameter.
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Hello Daniel,
I was just doing a quick search but you beat me to it, yes, that was
what the consensus of opinion was, set the GPS checksum parameter to
zero.
Monday, September 11, 2017
toggle quoted message
Show quoted text
Wasn't this already discussed ? If I'm not mistaken there's some
discrepancy with the GPS data checksum on some units (or settings in
the gps) , the workaround/solution is to disable the gps check (=0) parameter. -- 2E0ILY Best regards, Chris mailto:chris@...
--
Best regards, Chris Wilson (2E0ILY)
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Could be that it was
already discussed but some of us aren't glued to the computer anxiously
waiting for an email...
toggle quoted message
Show quoted text
September
11, 2017 at 5:43 AM Wasn't this
already discussed ? If I'm not mistaken there's some discrepancy with
the GPS data checksum on some units (or settings in the gps) , the
workaround/solution is to disable the gps check (=0) parameter.
|
Thanks Daniel and all others who responded.? Sorry if this has been discussed before. Will try this when I am back home.? 73
Manoj VU2CPL.?
Sent from my iPhone
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Show quoted text
On 11-Sep-2017, at 16:23, Michael Lloyd < mikell@...> wrote:
Could be that it was
already discussed but some of us aren't glued to the computer anxiously
waiting for an email...
September
11, 2017 at 5:43 AM Wasn't this
already discussed ? If I'm not mistaken there's some discrepancy with
the GPS data checksum on some units (or settings in the gps) , the
workaround/solution is to disable the gps check (=0) parameter.
|
|
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Hi all
Can someone clarify please: does this happen with the QRP Labs QLG1 GPS ? Or only with other GPS modules??
Does the checksum disable fix it??
I am curious as to whether it is just some noise on the line, which makes the checksum validation fail - in which case this is just a hardware issue specific to some people's installation; or, is it something to do with the ordering of the items in the GPS sentence - so that perhaps if they arrive in different order, or at slightly different times, then for some reason the U3S misses them. In the latter case, this could be resolved by a firmware change and I could investigate it.?
73 Hans G0UPL
On Mon, Sep 11, 2017 at 2:32 PM, Daniel Ekman (kng) <knegge@...> wrote:
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Hi Hans,
Hi all
Can someone clarify please: does this happen with the QRP Labs QLG1 GPS ? Or only with other GPS modules??
Mine is QLG1 which came as a part of U3S Deluxe kit and it suffers from no 3D display.
Does the checksum disable fix it??
Yes.
I am curious as to whether it is just some noise on the line, which makes the checksum validation fail - in which case this is just a hardware issue specific to some people's installation; or, is it something to do with the ordering of the items in the GPS sentence - so that perhaps if they arrive in different order, or at slightly different times, then for some reason the U3S misses them. In the latter case, this could be resolved by a firmware change and I could investigate it.?
It will be great if you can go into this.?
73
Manoj VU2CPL
|
Hello Manoj
If disabling the checksum validation fixes the lack of 3D fix information - then it suggests a hardware issue, not firmware. It does not conclusively suggest it - there still may be a firmware issue/solution... but the first thing to check is hardware. Do you have some separation between U3S and QLG1, and use shielded cable between them? And a clean power supply etc.? If noise is getting into your serial data and the checksum validation consequently fails, then suppressing the invalid data is exactly what is supposed to happen.?
73 Hans G0UPL
On Tue, Sep 12, 2017 at 9:47 AM, Manoj Kumar <vu2cpl@...> wrote: Hi Hans,
Hi all
Can someone clarify please: does this happen with the QRP Labs QLG1 GPS ? Or only with other GPS modules??
Mine is QLG1 which came as a part of U3S Deluxe kit and it suffers from no 3D display.
Does the checksum disable fix it??
Yes.
I am curious as to whether it is just some noise on the line, which makes the checksum validation fail - in which case this is just a hardware issue specific to some people's installation; or, is it something to do with the ordering of the items in the GPS sentence - so that perhaps if they arrive in different order, or at slightly different times, then for some reason the U3S misses them. In the latter case, this could be resolved by a firmware change and I could investigate it.?
It will be great if you can go into this.?
73
Manoj VU2CPL
|
Hans Hello Manoj
If disabling the checksum validation fixes the lack of 3D fix information - then it suggests a hardware issue, not firmware. It does not conclusively suggest it - there still may be a firmware issue/solution... but the first thing to check is hardware. Do you have some separation between U3S and QLG1, and use shielded cable between them? And a clean power supply etc.?
Both in same u3s deluxe case.? Connection is not shielded. Will change and let you know.? Power supply is clean as far as I can tell. But will try a battery.?
If noise is getting into your serial data and the checksum validation consequently fails, then suppressing the invalid data is exactly what is supposed to happen.?
Please give me a day to check this.?
Thanks?
Manoj VU2CPL
|
Hans,
An update.
I managed to do these.
1. Use shielded cable between GPS and U3S. 2. Tried 3 different power supplies. 2 SMPS and 1 Linear
There was no change and I had to change the gps check parameter to 0 to get 3D fix.
regards
Manoj VU2CPL
toggle quoted message
Show quoted text
On 12-Sep-2017, at 12:53 PM, Manoj Kumar < vu2cpl@...> wrote:
Hans Hello Manoj
If disabling the checksum validation fixes the lack of 3D fix information - then it suggests a hardware issue, not firmware. It does not conclusively suggest it - there still may be a firmware issue/solution... but the first thing to check is hardware. Do you have some separation between U3S and QLG1, and use shielded cable between them? And a clean power supply etc.?
Both in same u3s deluxe case.? Connection is not shielded. Will change and let you know.? Power supply is clean as far as I can tell. But will try a battery.?
If noise is getting into your serial data and the checksum validation consequently fails, then suppressing the invalid data is exactly what is supposed to happen.?
Please give me a day to check this.?
Thanks?
Manoj VU2CPL
|
Hi Manoj
That's very interesting. Did you try with some metres of separation between the U3S and QLG1??
It's a very difficult issue to investigate because I have never seen it here with my QLG1.?
I would be interested in a serial data capture of the serial data output of your QLG1, at the same time as it is showing this lack of 3D fix. Are you able to capture that data? It would show us immediately what the situation is. If you have a serial to USB converter you could capture the data on a PC terminal program. Or if you have an Arduino it is easy to configure it as a serial to USB converter too.?
73 Hans G0UPL
On Tue, Sep 12, 2017 at 11:59 AM, Manoj Kumar <vu2cpl@...> wrote: Hans,
An update.
I managed to do these.
1. Use shielded cable between GPS and U3S. 2. Tried 3 different power supplies. 2 SMPS and 1 Linear
There was no change and I had to change the gps check parameter to 0 to get 3D fix.
regards
Manoj VU2CPL
On 12-Sep-2017, at 12:53 PM, Manoj Kumar < vu2cpl@...> wrote:
Hans Hello Manoj
If disabling the checksum validation fixes the lack of 3D fix information - then it suggests a hardware issue, not firmware. It does not conclusively suggest it - there still may be a firmware issue/solution... but the first thing to check is hardware. Do you have some separation between U3S and QLG1, and use shielded cable between them? And a clean power supply etc.?
Both in same u3s deluxe case.? Connection is not shielded. Will change and let you know.? Power supply is clean as far as I can tell. But will try a battery.?
If noise is getting into your serial data and the checksum validation consequently fails, then suppressing the invalid data is exactly what is supposed to happen.?
Please give me a day to check this.?
Thanks?
Manoj VU2CPL
|
On Sep 11, 2017, at 11:58 PM, Hans Summers wrote: Can someone clarify please: does this happen with the QRP Labs QLG1 GPS??? Or only with other GPS modules??
I built a U3S, with QLG1. Worked great right from the start (I have limited electronics knowledge, and my only test equipment was a cheap DMM, so I was very pleased and a little surprised.)
Because I then wanted to package the U3S in the QRP-labs enclosure, I bought a second QLG1, which I built to use with an external GPS antenna, instead of the onboard patch antenna. The QLG1 with the external antenna does not show the 3D info. Plugging the original QLG1 with patch antenna back in (connection wires, settings all unchanged) shows 3D information again. Replace with the second QLG1 with external antenna - no 3D fix info displayed.
Does the checksum disable fix it??
Yes.
Any questions about the details, please ask.
Brad KW1BF
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Hi Brad
If you have a serial to USB monitor converter please can you capture the actual serial data text that is coming out of the QLG1 GPS when the 3D fix info is NOT displayed?
73 Hans G0UPL
On Tue, Sep 12, 2017 at 4:39 PM, Brad Farr <qrptalk@...> wrote: On Sep 11, 2017, at 11:58 PM, Hans Summers wrote:
Can someone clarify please: does this happen with the QRP Labs QLG1 GPS??? Or only with other GPS modules??
I built a U3S, with QLG1. Worked great right from the start (I have limited electronics knowledge, and my only test equipment was a cheap DMM, so I was very pleased and a little surprised.)
Because I then wanted to package the U3S in the QRP-labs enclosure, I bought a second QLG1, which I built to use with an external GPS antenna, instead of the onboard patch antenna. The QLG1 with the external antenna does not show the 3D info. Plugging the original QLG1 with patch antenna back in (connection wires, settings all unchanged) shows 3D information again. Replace with the second QLG1 with external antenna - no 3D fix info displayed.
Does the checksum disable fix it??
Yes.
Any questions about the details, please ask.
Brad KW1BF
|
Hi Hans,
I have the same problem with either the QLG1 GPS or an ebay UBLOX NEO-6M.
Both GPS units show "--" when checking is enabled and "3D' when checking is disabled.
I also have a QRP labs VFO/Signal Generator which I am using as the LO for the QRP labs receiver.
The VFO RXD and 1 pps inputs are connected in parallel so that one GPS drives both the U3s and?
the VFO. If I setup the VFO to display GPS data on line 2 of the VFO (#GV #GG #GF #GT) then the
VFO displays "A 3D 10 10" while the U3s is displaying "A -- f10 t10 s29".
I am attaching a capture file from the QLG1 taken while the error is occurring in case it may be of help.
73, Warren, K2GQT
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Hans,
Hi Manoj
That's very interesting. Did you try with some metres of separation between the U3S and QLG1??
No, the pcb is fixed into the enclosure ….?
It's a very difficult issue to investigate because I have never seen it here with my QLG1.?
I would be interested in a serial data capture of the serial data output of your QLG1, at the same time as it is showing this lack of 3D fix. Are you able to capture that data? It would show us immediately what the situation is. If you have a serial to USB converter you could capture the data on a PC terminal program. Or if you have an Arduino it is easy to configure it as a serial to USB converter too.?
Let me try and see if I can do this. I do have a usb to serial adapter. In the meantime I hope you might find the capture files shared by others.
Thanks for the support
Manoj VU2CPL
|
Hans, I've seen the same problem with some of the U3s/GPS kits that I've built. All of my GPS to U3s connections are made with shielded, twisted pair control cable that I use at work for Modbus and other communication protocols, soldered to a DB9F and DB9M connector pair. I use the same power supply in every one (to date I think I've built 7 or 8 for myself and others).?
73
NE5U
Mike
On Tue, 12 Sep 2017 10:07:49 +0300, "Hans Summers" wrote:
?
Hello Manoj
?
If disabling the checksum validation fixes the lack of 3D fix information - then it suggests a hardware issue, not firmware. It does not conclusively suggest it - there still may be a firmware issue/solution... but the first thing to check is hardware. Do you have some separation between U3S and QLG1, and use shielded cable between them? And a clean power supply etc.? If noise is getting into your serial data and the checksum validation consequently fails, then suppressing the invalid data is exactly what is supposed to happen.
?
73 Hans G0UPL
Hi Hans,
?
?
?
Hi all
?
Can someone clarify please: does this happen with the QRP Labs QLG1 GPS ? Or only with other GPS modules?
?
Mine is QLG1 which came as a part of U3S Deluxe kit and it suffers from no 3D display.
?
Does the checksum disable fix it?
?
Yes.
?
I am curious as to whether it is just some noise on the line, which makes the checksum validation fail - in which case this is just a hardware issue specific to some people's installation; or, is it something to do with the ordering of the items in the GPS sentence - so that perhaps if they arrive in different order, or at slightly different times, then for some reason the U3S misses them. In the latter case, this could be resolved by a firmware change and I could investigate it.
?
?
It will be great if you can go into this.
?
73
?
Manoj VU2CPL
?
?
|
Daniel Ekman SA2KNG