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Garmin NUVI charging cable - easy way?

primuspaul

Feb 7, 2018
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What's an easy way to make a cable like this?

http://pinoutguide.com/GPS/garmin_nuvi_power_pinout.shtml

I made one by soldering a +5V to pin 1, an 18 kOHM resistor between 4 and 5, and a GND wire to the resistor leg touching pin 5 (applying a clip-on heat sink between the resistor core and the pin to keep the leg from detaching from the mini USB connector).

I have absolutely no idea how I'm going to insulate this. Heat shrink is not an option because of the bent resistor (legs had to be bent to connect to the same connector). I can't think of anything except encasing this whole thing in hot glue, but then there is the issue of bulkiness and melting in the sunlight.

Anyone have any ideas?
 

Harald Kapp

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1) use an SMD resistor. These are much smaller and can easily be built into a plug.
2) use hot glue to keep the parts in place and insulate. Alternatively use epoxy.
3) Then cover with heat shrink tube for a neat look.
 

primuspaul

Feb 7, 2018
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I think I've seen those smd resistors, but even they are too big when the solder pins have barely enough clearance for the solder.

How do I shape the glue to later even allow heat shrink to fit?
 

Harald Kapp

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I think I've seen those smd resistors, but even they are too big when the solder pins have barely enough clearance for the solder.
They come in sizes as small as 0402, 0201... They'll fit into the space between two connector pins. It is much more likely that you won't be able to solder them ;)

How do I shape the glue to later even allow heat shrink to fit?
Use thermal protective gloves, or simply put a big blob of glue over teh solder joint and scrape away what's unnecessary when the glue has cooled down.
 

primuspaul

Feb 7, 2018
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They come in sizes as small as 0402, 0201... They'll fit into the space between two connector pins. It is much more likely that you won't be able to solder them ;)


Use thermal protective gloves, or simply put a big blob of glue over teh solder joint and scrape away what's unnecessary when the glue has cooled down.
When the glue is liquid, it doesn't hold it's shape, so often there won't be any usable blob. It will just be a thin coat of the glue and the rest will be on the table.

In the past I've taped a piece of paper into a cone shape (with the small end on the bottom) and wrapped it around a USB jack that has the interface end towards the bottom, but the resulting blob was quite big, big enough to generate doubts about being able to fit it into a GPS inside of a car.
 

primuspaul

Feb 7, 2018
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I ended up putting it into a tiny project box. It just fit. Then I filled it with high temp hot glue. Seems to work.

In the future, I think it will be easier to just solder 3 18 AWG wires to the pins and further down the wires to just strip the jackets (in different places) and connect the resistor there.
 
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