Please notice the green, double arrow, on the top right-hand corner of the GPS PCB. The parts of interest are the LED and its resistor.
I would like to install header pins (signal and GND) to access the PPS (Pulse Per Second) output of the GPS. This is a common DIY method to create a frequency standard from this configurable output.
There are three typical means of accessing this output:
- Remove the resistor and LED and solder a fine wire to the resistor input pad.
- Leave the resistor and LED in place and solder a fine wire to the input pin of the resistor.
- Solder a fine wire directly to the output pin of the GPS module, Pin #3.
Other Makers have had success with all three of these methods. But, they leave a couple of things to be desired… The fine wire, itself, is very fragile and it is not disconnect-able.
I have several of these boards. My first attempt was to attach the header pin directly to the resistor’s input. The tiny resistor instantly heated, the solder reflowed and the resistor was swept off of the board. I attached the pin to the pad, but the repeated heating and mechanical leverage of the pin lifted the pad. I exposed some of the trace and soldered to it, but it lifted for the same reasons.
I was successful with soldering the wire to the module pin. Phew!<g> I installed a SMA antenna connector on the three, elongated SMD pads, nearby, and I took ground from its GND pin. See picture.
I realized from this experience that, if I was to try this again, I would need to Super-Glue the resistor in place, before I attempt to solder the wire to its pin.
I also discovered that the frequency of the light is only discernible up to about 15 counts per second. That’s limits it usefulness, other than to indicate that there is output occurring. And, that the signal output strength is so weak that it really doesn’t need to be shared with the light. Therefore, I will not leave the resistor in place. I will remove it and have its pad as an available option for connecting the header pin.
You need to know that there is very little open space on the board with which to work. The closeup picture belies the situation. The whole board is only the size of two postage stamps. The antenna pads, mounting screw hole, vias and traces are all very close to the resistor.
I would like the header pin to be mounted horizontally to the board and exit the board to the rear. You can see that the mounting screw hole is a hindrance to this desire and must be accommodated, if this option is to be used. Accordingly, I remain agreeable to any means of attachment, horizontal, or vertical, that maintains a good electrical connection and mechanical support.
I have only thought of two means of mechanical support, glues of various types and drilling a pin hole.
So, I would appreciate your suggestions, cautions and options. I appreciate your help and look forward to hearing your creative ideas.

