Laser Pointer Wiring on Hero Prop

[DeckB26354]

Hi all

I have been looking at the wiring for the Laser pointer and cannot understand how it was done. It just does not make any sense to me. My Sidkit has 2 wires, one to each green LED and they simply wire onto the circuit with the Red Led and the battery.

So Why oh why are we looking at 4 wires on the Hero? If we look at the original Worldcom pictures we can clearly see that the 4 wires were together and running down the front of the side plate. They had been cut, presumably because they were drawing too much power from the Mallory battery to run all 7 LED's together.

http://propsummit.com/upload/303/laser_pointer_wiring_comp.jpg

These wires have npw been replaced, at least in part, with 4 more gleaming white (and rather thicker) wires. They have run 2 down the front of the plate as before but have run 2 down the inside (for the most part) perhaps because they are so chunky.

What I don't understand is how and why do they need 4 wires? Does anyone have any idea how they might be wired?

[phase pistol]

I assumed it was 2 wires to the front LED and 2 wires to the rear one.

Are we sure it wasn't ALWAYS four wires, with two running outside the case and two inside?

k

[andy]

The four wires meant they probably ran it in parallel instead of serial. Meaning that the power was equal to each.

Andy

[DeckB26354]

Ah, thanks Andy, that sounds like the answer I was looking for. I will read up on Parallel vs Series in electronic wiring!

I supose that means that the Red LED's would have been wired the same way?

Yes, it was ALWAYS 4 wires. Before and after the re-wiring. I'm not convinced that they had the wires running outside for the most part. I think it was running inside in all the photos and screen shots I have studied.

[andy]

Considering the red LEDs did not light up evenly, it is possible they were in series. Another possibility is that there was an external power source at one time that first ran to the Green LEDs before going into the clip. Possibly to make them brighter for the outdoor/brighter lit filming. Also to keep them from draining the battery on long shoots. It looked like the battery from the Profiles in History auction showed it soldered into place. So it may have been done for the last close up shots of the gun only. It could also explain the exterior screws on the ammo clip. Just a theory though.

Andy

[DeckB26354]

Interesting Andy

Having read up pn Paralell vs Series I have to agree with you on the Red LED theory; there is no way that the Red LED's would have behaved in the clearly uneven way that they did unless wired in series.

However, I would appreciate it if you would explain the theory of the exterior screws on the ammo clip in a little more depth!!

[andy]

One of the theories of the two screws on the outside left hand side of the ammo housing is that they were to run power into clip as two small binding posts in effect. But more likely they were in the to keep the clip from falling out since the interior latch would be missing.

Andy

[DeckB26354]

Well blow me down with a feather!

I had suspected that since first studying Karls' pictures, but had never voiced my theory, as not knowing that much about electronics, I thought it may sound rather silly.

What did it for me is that in Karls' photos one of the grub screws (the one with the gold coloured ring around it) can clearly been seen going through the housing and into the ammo cartridge, bending out the housing a little. Even more conclusively than that is the clear spot of solder on the underside of the gold coloured ring! Also, I don't feel that the cartridge would have had any problem staying in place, even with the interior latch missing; it's a pretty snug fit anyway.

Also, I think that IF they are indeed for additional power, they were for the green LED's. The reason I say this is that in the original photos of the gun taken when completed, we can see 4 Red LED's illuminatred perfectly but no greens...and the grub screws with that gold/brass coloured ring is all there. So no later modification. They must have had a purpose.

What I had a problem with figuring out (and still do) is if those two gub screws were let's say additional contacts to the battery terminals or the series cicuit how would they get them to line up and make the correct contact, with what is a removable object. In other words, when you slide the cartridge in and then screw the grub screws into place, getting them to "hit the right spot" would be very difficult to do. It's not like you can work from the inside out!

[steevy]

We still argue here whether the greens were ever lit at all.Amazing how much mystery there still is about this prop.

[propsjonnyb]

Just to add my twopennyworth , there should be four wires , two for each 'green ' LED and all seven LED 's, that's the five red and the two green worked off the same circuit operated by the simple on/off switch at the side. When the original prop was 'struck' to make it 'safe' , the firing pin was pulled, the barrel blocked and all the electronics cut. The remnants of this is want you see on the 'original' prop. I cannot say this categorically for this specifc prop gun ,but generally for all the prop working guns made, especially the stunt versions as I do know for an absolute fact they broke two - doing the ' gun through the wall ' scene !! This is how I've re-wired my own 'Coyle' Blaster exactly the same as the 'original' one.