Done with LimeSDR for a while:Repaired!

I was plugging the USB cable into the board and the connector snapped off. Clean break of every solder joint. I looks like it could have used a little more heat in the reflow process. I don’t have the equipment to solder it back on properly so for now I will move on to other projects. By the time I get this fixed I hope some of the software will be more stable.

Dang … i use a hobby heat wand for my smd work ( and a toaster oven too, but we won’t go into that)

Micro USB type? I have 3 spare ones.

Sorry to hear that…
That is the main reason why my lime is closed in the die cast aluminum box and
only USB cable goes out. Unit and cables already survived one drop from desk :smiley:

Heat gun with good tip and all done…ask someone with some practice on similar cases.

It’s too hot to do anything else so I took out my stereo microscope and a low powered iron with a very small tip and set to repairing. I mounted the connector back to the board by it’s sheet metal tabs but then I notice a single solder joint did not break cleanly and pulled a trace from the board. It looks like a direct run to IC14. My eyes are getting old for this kind of work but it looks easy enough to bridge the break.
I have mine mounted in an old Cobra 148GTL chassis. It already has a pattern punches in the cover for a fan. I was even going to figure out a way to put the switches and knobs to use. I have both SMA and N-type pigtails but I find the N-type more useful. The problem is how big they are. I had it pulled apart to change the antenna configuration and was putting it back together when I broke the connector.

True, I am using N only… home made pigtails.

From day one heat evacuation, with dust protection and rugged mechanic of case are
my major concerns…

Ok. SS_RX_P was the signal that was pulled from the board. I guess I need this. I touched all of the other legs back to their pads and used conductive ink to repair the missing trace. After the blob of ink dries and can be cleaned up I think it will work fine.

First try is failure. I think i got some conductive ink between pads. I don’t have meter probes fine enough to check for this and it’s hard to get a good look in this area.

Success! I was going to throw my board away but thought I would give it another try. I cleaned all of the conductive ink away and trimmed back the lead from the usb connector that had no pad on the PCB to attach to, having been pulled off.
I then, while looking through a 40x stereo microscope, cleaned the little foot of lead 5 on the chip 14. Man! This stuff is small! I built up a little more solder on it. I then took a single strand out of a stranded wire, maybe 30 gauge. I soldered this first to the usb lead. Then using an exacto knife and some custom made tiny tipped tools I made the little strand take a path to the chip lead. I finally got it to stick there with the soldering iron. I plugged it in verrrryyy carrrrrrefulllly and ran the LimeSuite test on it. Works!!! So I dropped some SuperGlue on the repair job to set it all rigidly in place and will be back to playing with it tomorrow. Well a little bit, anyway.


Good job! Any chance of a photo of the repair?

I thought of taking a photo but I don’t know if I can get a clear magnified image of this area. There is not much room between the back of the connector and the tiny chip. I will see if I can devise something

Use a cell phone to take a clear image … then crop/zoom the image … then post

Here it is. Thee is a little line of conductive ink left under the wire. A lot of the bright spots are light reflections form the super glue.

My workbench and the tools I used.


Wow. Well done… that’s pretty small alright