I lost my solder point on board! What I do?

[Nael]

Hello guys,

I have a small board with broken connector, I tried to re-solder that, but unfortunately I lost one of the solder points on board, now the solder doesn't stick on that point on board anymore. What can I do?

I attach a photo to show what happened.

Hint please.

 

[(*steve*)]

There are many forms of poor technique that can allow this to happen.

The general solution is to find where that pad was connected and use a short length of very fine wire to connect the pin to where it should be connected.

It is possible the pad was not connected anywhere. A description of the pinout of the connector, a schematic, or a service manual may help.

 

[Nael]

There are many forms of poor technique that can allow this to happen.

The general solution is to find where that pad was connected and use a short length of very fine wire to connect the pin to where it should be connected.

It is possible the pad was not connected anywhere. A description of the pinout of the connector, a schematic, or a service manual may help.

Thank you Steve, If I understand correctly is what you're saying to replace where the pad was with a short wire? But how I'm going to solder the wire there since the solder won't hold at first place!

 

[davenn]

Thank you Steve, If I understand correctly is what you're saying to replace where the pad was with a short wire? But how I'm going to solder the wire there since the solder won't hold at first place!

no, Steve is saying that you need to take a fine wire from the connector terminal out to a point in the pcb track that used to connect to the now missing pad
you will have to scrape a bit of the green varnish off the track so you can solder to it

so a better closer up photo of that area so we may possibly see what that connector pin used to connect to .... you may be lucky that it didn't connect to anything .... unused pin

 

[73's de Edd]

Sir Nael . . . . . . .

Looking at the connector and its mate at the PCB with mine old eyes, I am seeing 6 connections to which I am
ramdomly assigning contacts designations 1-6 to the connector and its mate on the PCB.
I may be off 180 degrees or they may have Alfa assignments.

It is plain to see :
Pin 1 is going to the ground plane of the PCB.
2 goes to TP5
3 goes to TP4
4 goes to TP3
5 is our connection to be solved
6 is receiving the serial digital output stream from the U1 capacitive sensing keyboard interface I.C. down below

Now your job . . . .if you accept it . . .(a la Mission Impossible ) . . . . . . is to check out pin 5 on the connector that you show and its companion plug in to see if there is a wire presence on its pin 5.
If so check it out for continuity to pin 1 which is ground.
A possibility for pin 5 is to be associated with a shielded line braid around that pin 6 signal. You can at least see
if they are using shielding around line 6.

As the board stands . . . . if there is no connection / wire being associated with the pin 5 of your male plug the
connection to the pcb was just possibly being an unused floating land.
If there was a connection where you are seeking one, likely it would be a small trace running to the foil finger
coming in towards that connection from the outer ground plane. A cleaning and magnified inspection just might reveal some minute torn foil remnants.

Then IF your research reveals the 5 being grounded . . . the inset shows the use of a soldered in wire spiral around the connector stub over to the 2 ground plane solder connections.


PCB and CONNECTOR . . . . .



73's de Edd

 

[Nael]

no, Steve is saying that you need to take a fine wire from the connector terminal out to a point in the pcb track that used to connect to the now missing pad
you will have to scrape a bit of the green varnish off the track so you can solder to it

so a better closer up photo of that area so we may possibly see what that connector pin used to connect to .... you may be lucky that it didn't connect to anything .... unused pin

Thank you Davenn, I'll scrape it today and hopefully will help

 

[Nael]

.

Sir Nael . . . . . . .

Looking at the connector and its mate at the PCB with mine old eyes, I am seeing 6 connections to which I am
ramdomly assigning contacts designations 1-6 to the connector and its mate on the PCB.
I may be off 180 degrees or they may have Alfa assignments.

It is plain to see :
Pin 1 is going to the ground plane of the PCB.
2 goes to TP5
3 goes to TP4
4 goes to TP3
5 is our connection to be solved
6 is receiving the serial digital output stream from the U1 capacitive sensing keyboard interface I.C. down below

Now your job . . . .if you accept it . . .(a la Mission Impossible ) . . . . . . is to check out pin 5 on the connector that you show and its companion plug in to see if there is a wire presence on its pin 5.
If so check it out for continuity to pin 1 which is ground.
A possibility for pin 5 is to be associated with a shielded line braid around that pin 6 signal. You can at least see
if they are using shielding around line 6.

As the board stands . . . . if there is no connection / wire being associated with the pin 5 of your male plug the
connection to the pcb was just possibly being an unused floating land.
If there was a connection where you are seeking one, likely it would be a small trace running to the foil finger
coming in towards that connection from the outer ground plane. A cleaning and magnified inspection just might reveal some minute torn foil remnants.

Then IF your research reveals the 5 being grounded . . . the inset shows the use of a soldered in wire spiral around the connector stub over to the 2 ground plane solder connections.


PCB and CONNECTOR . . . . .


73's de Edd

Wow Edd I really appreciate looking at my board closely, I will track those point as you mentioned and let you know of the result.

Thank you...

 

[shrtrnd]

While you're looking closely at your board, make sure that missing solder pad didn't wind-up against some other
connection on the board, creating an unwanted short someplace.

 

[73's de Edd]

ALSO check the back side of the of the board very closely as it also shows several small feed thru vias from one side of the PCB to its other side. So that connection might actually be on the other side of the board as a fine line as is being seen on pins 1-2-3 .


73's de Edd

 

[davenn]

Wow Edd I really appreciate looking at my board closely, I will track those point as you mentioned and let you know of the result.

Thank you...

his comments have a LOT of IFs seeing a better close up pic as I suggested would clear up a lot of things a reverse side pic would also be helpful

SHARP and Well lit