| goran | Posted: 25 Sep 2024, 01:04 AM |
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 Member Posts: 4 Joined: 25-September 24 |
I assembled the precision clock a while ago and turned it on. It never updated and ran for quite a while. The GPS fix LED is always on. I finally have time to look into it, so: welp? Any suggestion will be greatly appreciated.    ------------- |
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| mit | Posted: 25 Sep 2024, 02:37 PM |
 yeah whatever Admin Posts: 566 Joined: 4-May 16 |
In the pictures you've posted, there is no antenna fitted to the GPS module. It won't be able to get a signal without it. Did this maybe get knocked off at some point? Or was it never fitted? ------------- |
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| goran | Posted: 25 Sep 2024, 07:28 PM |
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Member Posts: 4 Joined: 25-September 24 |
Oops! It was there before, I just temporarily removed it to inspect the solder points as it was flapping around. ------------- |
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| mit | Posted: 26 Sep 2024, 08:25 AM |
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yeah whatever Admin Posts: 566 Joined: 4-May 16 |
Fair enough, it was worth checking! Do you know roughly when this clock kit was ordered? When the kit arrived, was the antenna already fitted to the GPS module? At some point I started testing every GPS module before shipping. If it arrived with the antenna already fitted then I've confirmed the GPS module is working, and the problem is likely a soldering issue. ------------- |
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| goran | Posted: 27 Sep 2024, 05:05 PM |
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Member Posts: 4 Joined: 25-September 24 |
It was shipped March 11th 2024. I honestly don't really remember if the antenna was attached, but I think not? ------------- |
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| mit | Posted: 27 Sep 2024, 05:39 PM |
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yeah whatever Admin Posts: 566 Joined: 4-May 16 |
Oh that's definitely one that I tested then, I've been doing that since at least 2022. If the antenna comes off quite easily, it might mean that the connector is damaged, it's a very flimsy connector that isn't mean for repeated disconnects. Look closely at the DIP socket for the ATtiny. A few of the sockets that got sent out about six months ago apparently had loose pins. A missing pin in the socket could cause a lot of problems but should be easy to spot. If you have a multimeter, check continuity of the TXD pin to pin 2 of the ATtiny (while the clock is turned off). Check the voltage on the VCC/GND pins of the GPS module, if there was a soldering error on the ground pin it may be able to power up by leaching power through another pin, but performance would be degraded. Check the clock with a different power supply if you can, a very noisy USB power adapter could be giving off interference. ------------- |
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| goran | Posted: 1 Oct 2024, 04:30 PM |
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Member Posts: 4 Joined: 25-September 24 |
QUOTE (mit)
If the antenna comes off quite easily, it might mean that the connector is damaged, it's a very flimsy connector that isn't mean for repeated disconnects. the connector seems solid. it took a bit of force to take it off QUOTE (mit)
Look closely at the DIP socket for the ATtiny. A few of the sockets that got sent out about six months ago apparently had loose pins. A missing pin in the socket could cause a lot of problems but should be easy to spot. the socket seems fine on visual inspection. I think I would have noticed missing ping when soldering as well. QUOTE (mit)
If you have a multimeter, check continuity of the TXD pin to pin 2 of the ATtiny (while the clock is turned off). tested and there is continuity between TXD and pin 2 QUOTE (mit)
Check the voltage on the VCC/GND pins of the GPS module, if there was a soldering error on the ground pin it may be able to power up by leaching power through another pin, but performance would be degraded. Well, there it is. It looks like there is no GND connection on the module at all. II ended up mangling one segment display while removing it, and I damaged another with the iron, but that should be an easy fix. Thank you so much for help with getting it running. ------------- |
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| mit | Posted: 1 Oct 2024, 05:25 PM |
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yeah whatever Admin Posts: 566 Joined: 4-May 16 |
Great you found the problem, yes desoldering the digits can be quite a challenge. If it helps, and if the damaged digit still has a working hyphen, you could swap it with one of the digits in the date that only needs to display a hyphen. I can also potentially send you some replacements, though different batches have minor differences. ------------- |
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