SparkFun Forums

[KalebPSpector]

So I've been tasked with designing a prop "superweapon" that uses a sequence of triggers and switches to ultimately play an explosion sound effect and trigger a camera flash transmitter. To make this as believable as possible, I'm adding as many interesting LED effects as I can. One effect I'd like to use involves placing an LED circular bargraph (COM-10595) around one of the switches and using a de-multiplexer to turn on the LEDs in a rotating sequence (four at once so one in each quadrant). However, the pins on the circular bargraph are a pain to solder wires to individually (I tried; now I need to order a new one because one of the pins broke off completely). Does anyone know of an easier way to solder this component that allows me full control of which LEDs are on or off?

I'm aware of the RingCoder breakout board but since I plan on placing the bargraph around a switch, I'm not sure that part is going to be of any use to me. If I'm wrong about that, let me know!

[Joeisi]

You should be able to get a breadboard and just cut out the center or wherever you need the switch to be, then solder the wires to the pins. The breadboard will reinforce each of the pins preventing them from breaking off.

[MichaelN]

If you're familiar with PCB CAD programs (and can wait a couple of weeks), I'd suggest getting 10 PCBs made for $10 at either Itead or Seeed Studio.

[KalebPSpector]

I should have clarified: my time frame (< 2 weeks) does not allow for me to get a custom PCB made or that's exactly what I would do.

You should be able to get a breadboard and just cut out the center or wherever you need the switch to be, then solder the wires to the pins. The breadboard will reinforce each of the pins preventing them from breaking off.

I'm assuming you're talking about the RingCoder breakout board? Do you know for a fact that removing the middle won't affect the connections to the LEDs or would you recommend getting more than one just in case?

[Joeisi]

No. Im talking about a copper clad board from Radio Shack or somewhere like that. Just stick the pins through and cut out where you don't want stuff. Then just point to point solder to the pins from the board.

[KalebPSpector]

I have a couple Radio Shack prototyping boards but they won't work because of the pin arrangement. Most protoboards are arranged like this:
.O O O
.O O O
.O O O
But the circular bar graph pins are arranged like this:
. O O
.O O O

If you know of a place where I can get protoboard that has that off-set arrangement of pins, let me know!

[MichaelN]

Given those requirements and tight deadline, I'd personally make a custom PCB at home. My favorite method is using iron-on transfer sheets (eg Press'n'Peel Blue) with a laser printer and clothes iron.

http://www.techniks.com/

[Tomdf]

Try using the radio shack board but just drill the extra holes where you need them and bridge the offset pins to the nearest pad.
It looks like if you tried to drill out the center sparkfun breakout board you would make the shift registers useless, not sure if you need those.

Let me ask you this, why is it a pain to solder to the pins directly? Do they break off just from handling the wires once they are soldered on? You could try getting some thin magnetic wire and wrapping it around the pins before you solder them, then you could use heatshrink to cover the pin and bundle the wires all together. Just make sure the wire can handle the current.