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thetang22
12-29-2019, 08:11 PM
I’ve been wiring up my Crystal Focus v9, and everything has gone well so far, until I got about 90% of the way through initial wiring. On page 46 of the user’s manual, it has wiring instructions for Simple Flash of Clash, which I was attempting to do. It has me soldering to the PEx1 pad. In doing so, I was clumsy and the pad tore away from the board. (This is something I experienced years ago on cheap has to boards, and had been extra careful on this board up until this moment).
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So I’m in a pickle, and I’m trying to figure my options. I’m re-reading the manual now to see if an answer becomes clear, but also thought it would be wise to ask here, in case the community can provide any help.

My hopeful gut reaction was that perhaps I could just use the PEx2 pad for FoC. So I soldered it up exactly as the manual suggests, with the exception of changing to the PEx2 pad. That didn’t appear to have any effect...which I kinda thought it would not, without perhaps changing some coding on the SD card (which I’m trying to see if that’s possible for this situation. Or is it an issue in which the FoC pad is hard-codes to be the PEx1 pad (which is now broken...)?

I’ve also seen some pretty advanced stuff about potentially repairing the removed pad, but that looks to be beyond my level of confidence.

Then there has also been talk of some pads that can be accessed from both sides of the board....and that just because the pad is broken on the bottom side of the board doesn’t mean it can’t be accessed from the top. But it seems this isn’t necessarily the case for every pad on the board...and I’m not sure if this particular one is accessible on the top. If it is, it appears like it’s 1/2 way under the block on the top of the board.

Another question/consideration - the PEx1 has 2 pads...the 1 I broke, and another it connects to, to it’s left. Would it be possible to simply bypass the broken pad and solder directly to the left pad? I have a resistor on the wire to the led...in case that is a concern.

Thanks again for any help.

Forgetful Jedi Knight
12-29-2019, 09:33 PM
Those two big square pads have to be bridged (generally with the resistor you were going to use for the LED assuming you’re using a 3.7V battery).

thetang22
12-29-2019, 11:09 PM
I had noticed that in a different wiring schematic pic I later looked up. I won't be able to get back to this until tomorrow, but I'm wondering....is the missing pad even technically needed if I resistor the wire and solder directly to the remaining pad (bypassing the broken one)? Or is their some functionality of that broken pad that will prevent it from working?

And if that is out of the question, can I use the PEx2 pads for FoC? (Provided I bridge them as intended)

Thank you

Forgetful Jedi Knight
12-30-2019, 06:23 AM
If you wire an in-line resistor, you should be able to use the back pads for both. Your “working one” won’t work as wired, because you didn’t bridge those two pads first.

scott
12-30-2019, 12:02 PM
I had the same thing happen on my first build and bridged with a resistor and wired to the pad that was still there. I have t done a cf9 in a year but you might also check if there is a pad on the top side that you can access.

Forgetful Jedi Knight
12-30-2019, 03:07 PM
I had the same thing happen on my first build and bridged with a resistor and wired to the pad that was still there. I have t done a cf9 in a year but you might also check if there is a pad on the top side that you can access.

There isn’t on those.

thetang22
12-30-2019, 06:37 PM
Luckily, I tested this morning and I was able to get FoC by using the PEx2 pad. I did bridge the pad, as was mentioned, and that definitely was a factor.

Thanks