The XBOX 360 HD-DVD high power laser thread

[daguin]

Dave, a thought before you make that jump:
just because you're driving a V8 doesn't mean you have to go 80 in that school zone...

With the 308T you could make a really dependable 40mW or whatever... or with a switch and a resistor you could make it dual power. I've done the latter with a red burner; it's 30mW normally but goes to 250mW when I attach a small magnet "key". (it triggers a tiny magnetic reed switch in the case, which switches in a shunt resistor).

It is probably in this behemoth of a thread, but I cannot find this information. Do we know what the threshold is on these 308T diodes? How about for the 0811's? Everybody's working the high end. How low could I go?

Peace,
dave

 

[danq]

How low could I go?

good question... let me pull another one (diode) and try... I killed my testee last night by improper extraction.

Actually what killed it was trying to remove its top, because the glass had become separated from the can. Dremel by shaky hand at moon-noon-thirty is not recommended for such operations...

 

[robjdixon]

i was wondering how hard it is to take off the copper wire pad attached to the diode. it seems much closer to the diode itself than the reds. are there any tips or tricks?

 

[IgorT]

What "copper wire pad" are you talking about? Do you mean the PCB with the connections?

It is quite hard to take off actually.. I had to spend quite a bit of time heating it up and vacum pumping the solder away, while pulling it out.. So i decided to partially mount it in an AixiZ module for heatsinking, before i continued.

It was slow, so do it very carefully. If it was a PS3 diode, i would have left it on, as it makes for easier soldering there. But it can make the "vice method" of press fitting it into an AixiZ module dangerous, by putting the force, through the PCB, onto the legs of the diode, instead of the base...

 

[daguin]

Remember, folks . . . and I am just as guilty as the rest of you . . . .

We have a whole sub-forum about blu-ray and violet lasers

http://www.laserpointerforums.com/forums/YaBB.pl?board=b_blurays

We don't need to keep piling everything into this one thread. It is getting unweildy.

Peace,
dave

 

[flogged]

[quote author=danq link=1209940381/348#352 date=1211475387]Dave, a thought before you make that jump:
just because you're driving a V8 doesn't mean you have to go 80 in that school zone...

With the 308T you could make a really dependable 40mW or whatever... or with a switch and a resistor you could make it dual power. I've done the latter with a red burner; it's 30mW normally but goes to 250mW when I attach a small magnet "key". (it triggers a tiny magnetic reed switch in the case, which switches in a shunt resistor).

It is probably in this behemoth of a thread, but I cannot find this information. Do we know what the threshold is on these 308T diodes? How about for the 0811's? Everybody's working the high end. How low could I go?

Peace,
dave
[/quote]

Well, I've worked with a couple of the low power xbox diodes, and a couple of the high powered diodes.

The low power diodes appear to have a lasing threshold at or below 20mA - I never went low enough to find out. The higher power diodes in the 803t sled don't appear to really start lasing until 40-50mA. I thought the diode was a dud in my latest pointer, cuz when I first turned it on the output was milky and dim at 45mA. Right around 50mA it finally started to lase, and brightened a lot beyond that.

These are just rough figures - each diode is unique.

 

[flogged]

i was wondering how hard it is to take off the copper wire pad attached to the diode. it seems much closer to the diode itself than the reds. are there any tips or tricks?

Extracting these diodes is not too difficult, though it is a tedious bit of work. I use a regular soldering iron, a long nose pliers, and an x-acto knife to do this.

First, the diode + heatsink pops neatly off the sled - a few dabs of some white goo hold it there. Next, I recommend removing the back wire pad BEFORE removing the diode from the heatsink - this will help keep the diode from getting too heat while you remove the back bit.

It's almost a three hand job. First I've got the soldering iron (just a plain 15 watt iron) warmed up and resting on a brick. Then I carefully hold the diode+heatsink using a pliers, and with the other hand I slip an xacto knife under one end of the pad. I then carefully touch the copper pad (PCB) to the soldering iron (touch the iron to the soldered diode legs) and twist the knife (once the solder has melted) a little to raise the pcb a bit. Don't hold the diode to the soldering iron for more than 3-5 seconds. Let it thoroughly cool off before continuing!! I then switch to the other side of the pad and continue lifting. Sometime I'll use the pliers. Just take your time and slowly work it off, never hold the diode to the iron for more than a few seconds at a time. Remember the diode is fragile, so it's not hard to rip its legs off while doing this - finesee required! Be patient.

To get the diode out of the heatsink I, again, use an xacto knife and a pliers. Hold the heatsink carefully with a pliers (the two long ends), and then use the xacto knife to slowly saw through the thin part of the heatsink. It takes patience and a lot of elbow grease, but you have more control than using a drill, and less vibrations too. Once the cut is deep enough I simply insert a small flat head jewelers screwdriver into the cut and twist to split the heatsink off the diode. Make certain to cover the diode window with some tape before doing this to protect it from metal shavings.

For the low powered xbox diodes I use a different technique. There's enough of the diode flange sticking out from the back of the heatsink to catch it with a sharp knife and pop it out. Like opening a clam.

I used to work in a shop repairing watches and replacing watch batteries, so I have a few skills working up close with small bits. No special tools needed. Though it does help to be near sighted, or at least have a good loupe so you can see what you're doing.

 

[daguin]

It is probably in this behemoth of a thread, but I cannot find this information. Do we know what the threshold is on these 308T diodes? How about for the 0811's? Everybody's working the high end. How low could I go?


Well, I've worked with a couple of the low power xbox diodes, and a couple of the high powered diodes.

The low power diodes appear to have a lasing threshold at or below 20mA - I never went low enough to find out. The higher power diodes in the 803t sled don't appear to really start lasing until 40-50mA. I thought the diode was a dud in my latest pointer, cuz when I first turned it on the output was milky and dim at 45mA. Right around 50mA it finally started to lase, and brightened a lot beyond that.

These are just rough figures - each diode is unique.

WOW! I just looked at the first post in this thread. I feel so sheepish. Drlava posted Climbak's data about his tests on the 308T diodes. Who goes back 30 pages?!? I guess I should have. I'm not sure if these measurements are without optics.

From climback:
I(mA) P(mW)
45 10
50 19
60 33
70 51
80 67
90 80
100 99
110 115

Yours is the first data I've seen about the 0811 diodes. Still need to know the threshold and what the output is at those lower inputs.

Peace,
dave

 

[IgorT]

I'm almost 100% sure climbak's measurements were without optics. There would seem to be weaker and stronger PRH803T diodes.. Or maybe they simply vary a little from one to another.

The first diode i tested did 80mW without optics at 90mA, so i thought Dr_Lava's graph is without optics as well. But it would seem my first diode is more like climbak's diode from the above data..


I haven't had time to test the others yet. When i do, i will post my measurements.

 

[danq]

yikes! gotta move fast to keep up around here!

Dave, I haven't done that test yet, had to prep for a finances discussion with my wife-in-law [sub]

[/sub].
(actually she's more like [sub]

[/sub])
That meeting just got postponed so now I only have Rosie the Wonder Dog to deal with.... you're after her ;-).

But I'll make this brief interlude worthwhile by posting a photo of the inside of a PHR-803t can:

 

[roSSco]

Mind blowing close up as usual.

 

[trublu832]

The first time I powered up my diode and focused it on a spot about 5' away it was already burning the test surface :-D Can anyone provide an optimum running amperage that will yield the most power with decent diode life? I'm using just an aixiz housing with a duty cycle of about a minute.

 

[danq]

the first couple pages of this thread (no wait, that other thread has climbak's stuff... hold on I'm searching...) should help you decide - at least one has gone days continuously at 90mA if I recall...

re-edit: here is a post by climbak that will get you in the neighborhood

 

[TheGr8Revealing]

so i got my 803 diode up and running for the first time. i just made a make quick driver on old board that i have. my meter says im pushing about 83mA, (3.92volts). it seemed very bright at first, (it was late day when i was putting it together). but a few hours later its very very dim. I can clearly only see it in the dark, and no clear visible beam at all. It never heated up really either. not even warm to the touch. Could i have created a faulty driver that somehow inhibits the 405nm LD?? I was really stoked about how everyone was talking about these new diodes... but mind is so dim. ive dropped alot of money on this whole project too... I bought a Kryton2 barrel expecting to put this diode in it, but if this is all im going to get from it, i think ive wasted my money. Any hopeful ideas?

 

[Glaserfan]

3.92v is too low... 4.5-5.5v is normal for these diodes. That could be the main reason for your troubles....

 

[flogged]

Turns out I was underpowering the diode in my pointer using the 811 sled from the xbox. See this thread:http://www.laserpointerforums.com/forums/YaBB.pl?num=1211171817/0

I turned the current up to 47.5 mA, from 35mA. It more than doubled the brightness of the pointer. So it appears either xbox diode is a step up from the PS3 diode.

Here's a new picture of the two pointers now:

Note how much dimmer the top pointer is (811 sled) is at 35mA, before I turned it up. Bottom pointer is 803t sled diode @82.5mA.

Judging from TheMonks slope, I'm hopefully getting around 25mW from the pointer now. It's bright.