board testing

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gillandro
Posts: 23
Joined: 17 Apr 2019, 15:57

Re: board testing

Post by gillandro » 18 Apr 2019, 23:14

last question on this subject but i gather that means the dot for the 6 pin resistor pack goes towards the left?

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marcelk
Posts: 403
Joined: 13 May 2018, 08:26

Re: board testing

Post by marcelk » 19 Apr 2019, 06:06

Yes, just follow the markings on the PCB.

Screenshot 2019-04-19 at 08.04.15.png
Screenshot 2019-04-19 at 08.04.15.png (143.01 KiB) Viewed 646 times

See also the instruction video: https://youtu.be/pXCHROQ-lS4

gillandro
Posts: 23
Joined: 17 Apr 2019, 15:57

Re: board testing

Post by gillandro » 02 May 2019, 19:50

got new kit and installed the resistor packs as discussed....new problem....led 5-led 8 stay fully lit when the power is supplied...what could i check with that issue? thanks

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marcelk
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Joined: 13 May 2018, 08:26

Re: board testing

Post by marcelk » 02 May 2019, 21:00

I'm sorry to hear, but please go back to the methods referred to before:
marcelk wrote:
17 Apr 2019, 17:24
There are tips and tricks on the Troubleshooting page. Specifically focus on these two sections:
  • No test pattern after build step 7
  • System doesn't start
All soldering connections must be good, none shorted, and all components placed in the correct orientation.

gillandro
Posts: 23
Joined: 17 Apr 2019, 15:57

Re: board testing

Post by gillandro » 02 May 2019, 21:58

making progress cleaned the board with ipa,,, test pattern worked for a few passes then stopped i will check solder joints tomorrow and clean the board again as that did help...but on a normal scenario how long will the leds do the back and forth pattern? thanks

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marcelk
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Joined: 13 May 2018, 08:26

Re: board testing

Post by marcelk » 03 May 2019, 07:35

Maybe you're using a power bank? See the instruction video on step 7 about how this can happen: https://youtu.be/l20m3mNZdx4?t=118

gillandro
Posts: 23
Joined: 17 Apr 2019, 15:57

Re: board testing

Post by gillandro » 03 May 2019, 16:48

im using a cube from a cellphone charger that says 5vdc output....is there a max ma rating? i gather what the board needs is probably in the manual

gillandro
Posts: 23
Joined: 17 Apr 2019, 15:57

Re: board testing

Post by gillandro » 03 May 2019, 17:33

btw i repaired the other board and it has the exact same issue

gillandro
Posts: 23
Joined: 17 Apr 2019, 15:57

Re: board testing

Post by gillandro » 03 May 2019, 17:41

apple wall plug output 5v and 1a

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marcelk
Posts: 403
Joined: 13 May 2018, 08:26

Re: board testing

Post by marcelk » 03 May 2019, 23:58

If the "Power OK" is always steady, yet still sometimes your LEDs are running a pattern and sometimes they're not, it can only be one (or a couple) soldering joints that are problematic. That's good news, because you can always revisit such connections with a soldering iron and perhaps do some backside cleaning. Always pay special attention to the ground pin joints. The excel sheet can help as well. The effects of such issues can be intermittent. The component orientation will be fine in that case, as the LEDs can't ever run their pattern with any reversed ICs installed. When the LEDs run, the computer is actually executing software that's built-in the EPROM (and it should give a video signal as well while it's doing that).

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