Laser Harp - Success!

[andy_con]

that is something else.

just amazing, great work mate.

whats the cost of a laser harp to make then??

[shobley]

Well....

Depending on $/rest of world ratio...

$1000 - $1200.

The scanner kit was about $330 - but you only need one channel.
(This was 20K, but I bet a 10K would do it)
Laser was $250 (ebay) for a 250mw, and $650 for a 450mw.
Boarduino, sensors, circuit board, wire etc... about $300.

Getting 694 views on Youtube in 2 days - priceless.


So in UK money about 14 shillings and sixpence at the moment...

Although I've probably spent close to $5000 developing it over the years, when I needed to learn about scanning I bought some DT40s and a USB DAC.

Also lots of burned chips, and failed photodiode sensors.

(Actually if I were to put the other scanner axis back I could vary the y position of the beams like a piano keyboard. Hmmmm....)

Steve

[andy_con]

i see, i would love to build onoe of them, but would have it as drums

sadly bit to difficult for me.

[shobley]

Oh and you need an oscilloscope for testing too...

[andy_con]

ive got 4 of them LOL

do you really need such a powerful laser?

[shobley]

When I was testing I used a 250mw laser, and this works fine. It doen't show up too well for the crowd though.

For a long time I thought I needed a 500mw+ laser because the sensors weren't able to detect the reflection over about 12". It was when I goofed up the detection circuit that it became *really* sensitive and worked over 20 feet.

The 450mw is too bright, I need to put another ND filter over the sensor - the smoke can set it off, but if you want the crowd to be able to see it then you need this power range.

I've come to the conclusion that the reason JMJ's latest harp has the beams bounce over the crowd's head is so that they can see it with a much lower power laser. Beams are more visible in parallel, than perpendicular to the viewing direction - but I bet you know that already.


It's not reallly that hard to make - lots of soldering though, and the trick with SPI (Arduino -> DAC chip) is to send the instructions twice. For a long time this did not work.

[andy_con]

would luv to see a guide on how to make it

[shobley]

I'm workin' on it...

[andy_con]

if u need a good site to host it on

www.laser-man.co.uk

[ImageLight]

Shobley, you ROCK dude.