Permanent JST connection on PogoPlug mobile

I ruined a board trying to connect a JST connector for permanent serial console access, and I'm hoping to avoid ruining my new board. I see that 3 of the pads are holes and I can easily remove the solder from the holes. Piece of cake.

But the 4th pad (ground) doesn't appear to be a hole at all. No matter how hard I tried (and I obviously tried too hard) I can't get through it. I tried trimming the pin on the connector, so that I'd have 3 pins going all the way through and one just sitting on the pad, with hopefully enough contact to serve as a proper ground.

When I connected the serial cable and powered up, I let the smoke out of something (UART maybe?). I'm guessing it was all my poking and prodding. $7 down the drain -- on to the next board!

How does one properly solder a JST connector in this scenario? I've seen bodhi mention in a few threads that he has connected JSTs to some of his v4 boards, so it must be possible with the proper technique.

I know I can simply solder wires to the pads I need, but I'm looking for something cleaner and more finished, I guess. If I'm trying to do something that's simply beyond my capabilities, then I'll defer to direct wire soldering.

Finally, a confession -- I'm much more adept at software than I am at hardware mods. I have sufficient tools to do the job, just need a little guidance from the more experienced hardware hackers.

Thanks!

GeekSmith,

Do you use the header like this JST 2.0?

http://www.ebay.com/itm/20SETS-Mini-Micro-JST-2-0-PH-3-Pin-Connector-Plug-with-Wires-Cables-100mm-/361541400332

I'm also a software guy so I usually buy my EE friends a good lunch for this job :) But we have many seasoned HW modders here, they could give you some useful advise.

-bodhi
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Ah, yes -- a good EE is a very valuable friend. Wish I had one that lived a bit closer! Can you tell on your board how they got ground attached?

I though of soldering a wire (my EE buddies would call it snot wire) to the trimmed pin, then looping that over to the bottom side of the board and soldering the other end to the pad on the underside. Not sure if that's a good solution, as I haven't dared to try anything on my pristine board yet.

For the JST, I got something similar -- I already have some audio cables with the male end, so I just bought the sockets.
http://www.ebay.com/itm/121126554861?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT

GeekSmith,

> Ah, yes -- a good EE is a very valuable friend. Wi
> sh I had one that lived a bit closer! Can you tell
> on your board how they got ground attached?
>

I recalled he desoldered the buttons, and then put in the header, and solder them in. A professional job that looks exactly as factory. That's it. And all I needed to do was identify the correct TX, RX, GND pins and connect them to the serial converter module.

-bodhi
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the simplest way i do it - is not to use "solder" at all. what i use is solder paste and use the heat of the iron held close to the pad to do the work for me.

in terms of finding a ground, any exposed metal connector i.e. usb port is a good place to fasten the ground to

Gravelrash Wrote:
-------------------------------------------------------
solder paste
>

Nice, that's on my next order. And here I thought paste was for stained glass and plumbing. Nice page about solder paste.

=========
-=Cloud 9=-



Edited 1 time(s). Last edit at 02/02/2017 09:31AM by JoeyPogoPlugE02.

Thanks for the advice, folks -- while I haven't decided whether to bribe a professional, order some solder paste, or wire up to a different ground, I'll post my results when I figure it out.

Love the forum, have learned and gotten a lot of help by simply lurking.

Gravelrash,

> the simplest way i do it - is not to use "solder"
> at all. what i use is solder paste a
> nd use the heat of the iron held close to the pad
> to do the work for me.

That might have been what my friend did. But I don't know for sure.

-bodhi
===========================
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@bodhi -- If you have a unit open and accessible, can you see if the the ground pin on the socket goes all the way through the board?

GeekSmith,

> @bodhi -- If you have a unit open and accessible,
> can you see if the the ground pin on the socket go
> es all the way through the board?

Sorry I don't have one off-line right now. Anyone?

-bodhi
===========================
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i should know this... but memory fails me at the moment, im currently working on a wireing loom for a classic moped so wont have time in the near future to look.

GeekSmith Wrote:
-------------------------------------------------------
> @bodhi -- If you have a unit open and accessible,
> can you see if the the ground pin on the socket go
> es all the way through the board?

I too will be out of action for a while. But if you hold on a while I'm sure one of us can try or look. I lack precision soldering equipment (this will change) and more importantly a big, fat magnifying glass on an arm, but one by one the parts are tricking in and shouldn't be too long and hopefully I can try stuff like that.

To that end, I'm thinking of a mid-future Wiki page itemizing the kind of parts that are good to have on hand to cover most stuff. Because these parts are usually cheap and may as well get the 10-30 day delivery out of the way beforehand.

=========
-=Cloud 9=-

Success! Even with the soldering skills of a software engineer, I was able to attach the JST connector and use it without letting the smoke out. I removed the solder from the 3 holes that go through the board. I also removed as much solder as I could from the pad for ground.

I then clipped the pin on the connector that goes to ground, and used solder paste on the cut pin and the ground pad. I was able to get enough heat from the bottom pad and the top of the pin to make a good electrical connection. I soldered the other 3 pins from the bottom side and the connector is working great.

I have another board to work on, and now that I know how to do it I'll take some pictures to share when I modify that board. Thanks for the tips! Solder paste was the key.

--
GeekSmith
"Let smiths perform the work of smiths"

GeekSmith Wrote:
-------------------------------------------------------
> Success! Even with the soldering skills of a softw
> are engineer, I was able to attach the JST connect
> or and use it without letting the smoke out. I rem
> oved the solder from the 3 holes that go through t
> he board. I also removed as much solder as I could
> from the pad for ground.
>
> I then clipped the pin on the connector that goes
> to ground, and used solder paste on the cut pin an
> d the ground pad. I was able to get enough heat fr
> om the bottom pad and the top of the pin to make a
> good electrical connection. I soldered the other 3
> pins from the bottom side and the connector is wor
> king great.
>
> I have another board to work on, and now that I kn
> ow how to do it I'll take some pictures to share w
> hen I modify that board. Thanks for the tips! Sold
> er paste was the key.

Congrats! now you have better soldering skill than I do :)

-bodhi
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GeekSmith Wrote:
-------------------------------------------------------
> Success
> I then clipped the pin on the connector that goes
> ...

Great descriptive writing too GeekSmith; even without pictures I can comprehend what you're saying.

One of my life's rules, is to invest in one good tool a year, and maybe this year it'll be a precision soldering station. Knock out that SATA on Pogoplug Mobile first thing :-)

=========
-=Cloud 9=-

we demand photos :) we luurve photos here :)))

Your wish is my command! I did a write-up of the process. Enjoy!

Adding a JST serial connector to the PogoPlug Mobile

--
GeekSmith
"Let smiths perform the work of smiths"

GeekSmith Wrote:
-------------------------------------------------------
> Your wish is my command! I did a write-up of the p
> rocess. Enjoy!
>
> [url=http://geeksmith.blogspot.com/2017/02/adding-
> jst-serial-connector-to-pogoplug.html]Adding a JST
> serial connector to the PogoPlug Mobile[/url]


WOW! ]outstanding job me appreciates :-) I wonder if this board would mind having epic helps like that outsourced on the Wiki? Regardless, thanks GeekSmith

=========
-=Cloud 9=-



Edited 1 time(s). Last edit at 02/18/2017 11:07PM by JoeyPogoPlugE02.

GeekSmith Wrote:
-------------------------------------------------------
> Your wish is my command! I did a write-up of the p
> rocess. Enjoy!
>
> [url=http://geeksmith.blogspot.com/2017/02/adding-
> jst-serial-connector-to-pogoplug.html]Adding a JST
> serial connector to the PogoPlug Mobile[/url]


Well done sir, excellent write up..... Mr_Bodhi, if you havent already, could you add this to your Wiki?

You giants compile with kings, yet solder with the common man :-D

=========
-=Cloud 9=-

> Well done sir, excellent write up..... Mr_Bodhi, i
> f you havent already, could you add this to your W
> iki?

Done. Thanks Gravelrash for the solder paste advice!

Execellent job GeekSmith :)

-bodhi
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You're all too kind -- thanks again for your help and suggestions. I'm glad I could make a small contribution to the community here.

--
GeekSmith
"Let smiths perform the work of smiths"