I also Used a strobe light from walmart as my blue cell light I got for $10.It has a knob and can blink slow or very fast. We made it so it would fit between the foam perfectly so I could just simply slide it out to change the battery. I also used electrical tape to tape off everything except the thin line.
You can also see how I did a lot of this at my forum "My inexpensive Proton Pack for $100 me and my brother made…
Here
You can view all my post about inexpensive props here…
Thanks

