Need help finding PHR-803T diodes for NASA

pullbangdead · May 24, 2010

lasersbee said:
Well... let's see... referring to the inflated prices the Gov paid for toilet seats
an other things... I have 10pc PHR803T LDs still in sleds...
I can let NASA have them at the incredibly low Price of $189,000.00 USD
and I will personally deliver them on my Harley...

Just send me the Purchase Order and it's a done deal...

Jerry

You know the "toilet seat" story is a red herring, right?

"The United States military services are often in the position of making equipment last decades longer than originally designed. For example the B-52 bomber is more than 50 years old and expected to be useful for another 20 years. The famous toilet seat came about when about twenty Navy planes had to be rebuilt to extend their service life. The onboard toilets required a uniquely shaped fiberglass piece that had to satisfy specifications for the vibration resistance, weight, and durability. The molds had to be specially made as it had been decades since the planes original production. The price of the "seats" reflected the design work and the cost of the equipment to manufacture them.

The problem arose because the top level drawing for the toilet assembly referred to the part being purchased as a "Toilet Seat" instead of its proper nomenclature of "Shroud". The Navy had made a conscious decision at the time, not to pay the OEM of the aircraft the thousands of dollars it would take to update their top level drawing in order to fix this mistake in nomenclature.

Later some unknown Senate staffer combing lists of military purchases for the Golden Fleece Awards found "Toilet Seat - $600" and trumpeted it to the news media as an example of "government waste." The Senate then wrote into the appropriations bill that this item would not be purchased for anything more than $140.00. The shroud has never been purchased since, as no one can make the shroud at that price.

President Reagan had actually held a televised news conference, where he held up one of these shrouds. During the press conference, he explained the true story. The media of the time, and still today, incorrectly reports that the Pentagon was paying $640.00 for a $12.00 toilet seat."

------------------------------------------------------------

As to the OP, very cool. There are some amazingly cheap, yet very high quality diodes, aren't they? The lab I work in makes violet laser diodes, and yet we still buy and use these PHRs for several different applications. None of our applications are as lofty (haha, I cracks myself up) as yours, but still, we've used dozens of them.

alanbrito · May 24, 2010

k-shell said:
Goddard Space Flight Center (GSFC) in greenbelt maryland, Astrophysics and exploration sciences building.

What kind of projects were you working on when you were at nasa??

just laser processing, texturing and cleaning of titanium plates. really enjoyed working there, I would just stare out the window and watch a bunch of F22s do acrobatic training maneuvers right next door at Langley AFB.

Eudaimonium · May 24, 2010

Well, I had to suck a neg rep sooner or later in my life...

ElectroFreak,
I have apsolutely no idea of any kind of "exitation" with UV light, that can be used to produce X-Rays, to be used for atmospheric communications.

First of all, You'd logically expect for a guy working in NASA to have is own suppliers, if not then at least have enough financial support to go higher than plain PHR (think along the lines of 8x or 12x BDR drives), next even so one would think the guy could do as much as click the advertisements that all around the forum which would take him to the links you all provided him.

Sorry if my logical algorythms confuse you. Not everyone can be a genious you know.

EDIT: Well, I think it goes without saying that the entire thing DID look like a joke - which was confirmed to the first person I linked the thread to on IM - He also said : Sure sure whatta joker.
But then again, that's my logic.

ElektroFreak · May 24, 2010

"Not everyone can be a genius"? So you're a self-proclaimed genius now? (note the correct spelling, any "genius" would know how to spell the word) And you wonder why I negged you.. Time to step off that high horse, my friend.

Let me get this straight: You don't know of any methods of exciting x-rays with a blu-ray laser, so therefore such a thing must not exist or be possible. Are you a walking encylcopedia of all himan knowledge? I sure as hell don't know of any way to excite x-rays with a blu-ray laser either, but I'm not so arrogant and over-confident that I would immediately discount the possibility on the basis that I've never heard of it before.. There are MANY scientific and physical principles that I don't fully understand.

The OP might not work for NASA at all.. This whole thing could easily be a complete fabrication, but I see no reason to talk down to someone because of what seems to me to be a simple, straightforward question. To me, the question seemed very easy to understand: "where can I get PHRs using a credit card?" Where's the joke? Maybe it's because I'm not a genius who can't spell.. maybe that's why I don't get the joke.

Also, pullbangdead just stated that UCSB uses PHRs for various purposes. Don't you think an internationally renowned university would have better sources? But yet they use PHRs.. Oh, but wait, that must be a HUGE joke too. You'll forgive my mental ineptness at not being able to comprehend your weird sense of humor.

And yes, I know there's a language barrier here, but I'm not the one claiming to be a genius.. If you're really a genius, then a silly language barrier shouldn't be a problem.

You might be completely right about this being false, but when I see someone being an arrogant asshole for no reason at all, I dole out a neg rep. As far as I'm concerned, you earned it, especially when your next move was to come here and talk about what a genius you are. Clearly you're not "genius" enough to understand tact. Since you stated to me in PM that you don't put any stock in the rep system, then I guess it shouldn't bother you that I'll be deducting more every time I'm able.

If I misunderstood this thread and your reaction to it, I apologise. The self-aggrandizing is a little much though.

Eudaimonium · May 24, 2010

ElektroFreak said:
"Not everyone can be a genius"? So you're a self-proclaimed genius now? (note the correct spelling, any "genius" would know how to spell the word) And you wonder why I negged you.. Time to step off that high horse, my friend.

Let me get this straight: You don't know of any methods of exciting x-rays with a blu-ray laser, so therefore such a thing must not exist or be possible. Are you a walking encylcopedia of all himan knowledge? I sure as hell don't know of any way to excite x-rays with a blu-ray laser either, but I'm not so arrogant and over-confident that I would immediately discount the possibility on the basis that I've never heard of it before.. There are MANY scientific and physical principles that I don't fully understand.

The OP might not work for NASA at all.. This whole thing could easily be a complete fabrication, but I see no reason to talk down to someone because of what seems to me to be a simple, straightforward question. To me, the question seemed very easy to understand: "where can I get PHRs using a credit card?" Where's the joke? Maybe it's because I'm not a genius who can't spell.. maybe that's why I don't get the joke.

Also, pullbangdead just stated that UCSB uses PHRs for various purposes. Don't you think an internationally renowned university would have better sources? But yet they use PHRs.. Oh, but wait, that must be a HUGE joke too. You'll forgive my mental ineptness at not being able to comprehend your weird sense of humor.

And yes, I know there's a language barrier here, but I'm not the one claiming to be a genius.. If you're really a genius, then a silly language barrier shouldn't be a problem.

You might be completely right about this being false, but when I see someone being an arrogant asshole for no reason at all, I dole out a neg rep. As far as I'm concerned, you earned it, especially when your next move was to come here and talk about what a genius you are. Clearly you're not "genius" enough to understand tact. Since you stated to me in PM that you don't put any stock in the rep system, then I guess it shouldn't bother you that I'll be deducting more every time I'm able.

If I misunderstood this thread and your reaction to it, I apologise. The self-aggrandizing is a little much though.

Language barriers at it's best---

The .. other side of the "Not everyone can be a genious" statement was directed at me - saying that not everyone - me included- can be a genius, so Iam self proclaimed NOT -genious and...

Ahh... why do I even bother.

Whever such a statement arrises where one can take offence, a huge drama mast arise, since everyone is used to taking offence instead of actually thinking what I was trying to say.

Why just looking out trouble to cause?

I take it that you saw the PM?

Where I said that you clearly have something against me - point made.

Let's take it to personal messaging eh? Let's not ruin the thread.

ElektroFreak · May 24, 2010

ElektroFreak said:
If I misunderstood this thread and your reaction to it, I apologise.

I'll just quote what I already said at the end of my last post. Misunderstandings do happen..

k-shell · May 25, 2010

maybe this will end the confusion:

http://gsfctechnology.gsfc.nasa.gov/TechSheets/XRAY_Goddard_Final.pdf

in the diagram it shows a UV LED as the excitation source, instead of an LED i am experimenting with laser diodes.
I work very closely with Keith (the scientist picturepd in the article) and all we wanted was some diodes to play with. I was a hobbyist laser builder a few years back and have built some PHR's into flashlights in the past, so i knew LPF was a good source of information. now could we please put all this behind us so you guys could possibly help us in getting this project off the ground (no pun intended)?

thanks for all the help so far, and im not here to bullshit anyone, just doin my job and im damn proud of it too! if we get funding then one day i might be able to tell you all that we're sending PHR's into orbit!!

you all rock!!

[EDIT]

Eudaimonium said:
First of all, You'd logically expect for a guy working in NASA to have is own suppliers, if not then at least have enough financial support to go higher than plain PHR (think along the lines of 8x or 12x BDR drives), next even so one would think the guy could do as much as click the advertisements that all around the forum which would take him to the links you all provided him.

Our supplier would typically be Digikey or Nichia but i dont think digikey has any and im not willing to pay the outrageous price Nichia is asking. secondly, its not about output power. we dont need much! a few mW is more than enough. the key here is how quickly they can be modulated!
and yes i could have spent a little time searching, but honestly im pretty busy in the lab and i wanted to give you guys a taste of some new concepts and uses for the PHR's

hope i didnt start off on the wrong foot, and definitely no hard feelings dude!

pullbangdead · May 25, 2010

k-shell said:
Our supplier would typically be Digikey or Nichia but i dont think digikey has any and im not willing to pay the outrageous price Nichia is asking. secondly, its not about output power. we dont need much! a few mW is more than enough to excite the photomultiplier in the new design. the key here is how quickly they can be modulated!
and yes i could have spent a little time searching, but honestly im pretty busy in the lab and i wanted to give you guys a taste of some new concepts and uses for the PHR's

Exactly. These things are quality diodes, and they're EXTREMELY CHEAP. A research lab can pick up a dozen to play around with very easily, instead of paying hundreds for one diode from a "legitimate source". We can just make a violet diode if we really wanted to, but these PHRs are easy, reliable, they perform excellently and consistently, they're CHEAP, there are no downsides. Once I introduced them to our lab, we quickly found multiple uses for them beyond the first use we intended them for, which was a photoluminescence set-up. Now with every growth run we do, every sample we make, the sample gets put under a PHR with a spectrometer to measure the PL spectrum, along with a couple of other quick-feedback tests.

lasersbee · May 25, 2010

k-shell said:
maybe this will end the confusion:

http://gsfctechnology.gsfc.nasa.gov/TechSheets/XRAY_Goddard_Final.pdf

in the diagram it shows a UV LED as the excitation source, instead of an LED i am experimenting with laser diodes.
I work very closely with Keith (the scientist pictured in the article) and all we wanted was some diodes to play with. I was a hobbyist laser builder a few years back and have built some PHR's into flashlights in the past, so i knew LPF was a good source of information. now could we please put all this behind us so you guys could possibly help us in getting this project off the ground (no pun intended)?

thanks for all the help so far, and im not here to bullshit anyone, just doin my job and im damn proud of it too! if we get funding then one day i might be able to tell you all that we're sending PHR's into orbit!!

you all rock!!

[EDIT]

Our supplier would typically be Digikey or Nichia but i dont think digikey has any and im not willing to pay the outrageous price Nichia is asking. secondly, its not about output power. we dont need much! a few mW is more than enough to excite the photomultiplier in the new design. the key here is how quickly they can be modulated!
and yes i could have spent a little time searching, but honestly im pretty busy in the lab and i wanted to give you guys a taste of some new concepts and uses for the PHR's

hope i didnt start off on the wrong foot, and definitely no hard feelings dude!

That .PDF info at the beginning in your first Post would have saved a
lot other Posts and would have gotten your PHR LDs a lot faster...

The negativity comes from the Scammers and Liars that come to
the Forum to Troll...
With that .PDF it is clear what the the project is and it makes sense..

Jerry

k-shell · May 25, 2010

lasersbee said:
That .PDF info at the beginning in your first Post would have saved a
lot other Posts and would have gotten your PHR LDs a lot faster...
Jerry

yea sry bout that, i was at work and didnt really have time to track that pdf down.

So does anybody have any idea how fast one of the PHRs might be able to be pulsed?

I need to get a decent burst of photos out of a 10 nanosecond pulse.
im not using a driver circuit but a function/pulse generator.
so im wondering what might be a safe maximum voltage to apply to the diode for such a short pulse??

sk8er4514 · May 25, 2010

k-shell said:
yea sry bout that, i was at work and didnt really have time to track that pdf down.

So does anybody have any idea how fast one of the PHRs might be able to be pulsed?

I need to get a decent burst of photos out of a 10 nanosecond pulse.
im not using a driver circuit but a function/pulse generator.
so im wondering what might be a safe maximum voltage to apply to the diode for such a short pulse??

Hey thanks for checking out my site. Were you the guy asking for millions of 405nm diodes though? Someone messaged me wanting 0.5mW 405nm diodes and they needed over 1 million. lol

I directed them to Sony or Sharp.

The PHRs and any laser diode are designed to be pulsed very quickly, I'm not sure what the frequency is though. I tried doing a google search but couldn't find the correct information. Some other 405nm diodes appeared to range from 50ps to 1ns... so I don't know.

Pulse generator should be fine.

As far as the voltage goes it will depend on what current / power output you're looking for. I'd start at around 5V though.

I'm sure others will have more information for you here though.

thanks,
Kendall

TTerbo · May 25, 2010

not doubting you but i would have thought a nasa guy would have all the info already?
and kendal. what is the mW of the phr -803t sled? i believe they burn,
cheers

HIMNL9 · May 25, 2010

k-shell said:
yea sry bout that, i was at work and didnt really have time to track that pdf down.

So does anybody have any idea how fast one of the PHRs might be able to be pulsed?

I need to get a decent burst of photos out of a 10 nanosecond pulse.
im not using a driver circuit but a function/pulse generator.
so im wondering what might be a safe maximum voltage to apply to the diode for such a short pulse??

Consider that, usually, they are used in players, so they are not the maximum ..... anyway, AT LEAST in the megahertz range, considered the normal field of usage ..... readers can at least work at 3X, for error correction cycles, if not for other .....

And if you want to be more sure, an SF-AW210 or a GGW diode are also better, and still cheap enough (around 30$ or less for the SF type, if i recall correctly) ..... being used in the burners, you already know that they are especially designed for pulsed use, and being used in 6X burners, you also know that they are used for write at a maximum (theorical, at least) speed of 27MB/s (for the bluray support, the speed is 1X=4,5MB/s)

EDIT: about the voltage ..... laser diodes are drived in current, as normal leds, not in voltage, so you need to calculate it in function of the VF and the current that you want to use for the diode ..... just as example, supposing that you want to use a SF-AW diode at 200mA, and that this diode have a VF of 4,5V at 200mA, and you want to use a 100 ohm resistor as limiter, then you need (Vsupply minus VF) divided resistance = 0,2A ..... that gives you, reversing it, 24,5V (20 V for have 200mA in the circuit with 100 ohm resistor, plus the 4,5V of diode VF) ..... ofcourse, you can also use lower resistors for get the same current (just continuing the same example, if you use 10 ohm you need 6,5V only), but remember that, more you lower the resistance, more high go the errors in case of tolerance shifting of the resistor value or from changes of the voltage (same example again, if your power supply go out of 1V for tolerance or noise or anything, with 24,5V and 100 ohm you reach 25,5V, that give you 210mA instead 200, where instead with the 6,5V and 10 ohm, you go from 6,5 to 7,5V, and this give you 300mA instead 200 .....

)

ReNNo · May 25, 2010

Just a second...
LEDs don't acts the same as laser diodes.

If you connect LED to its nominal voltage (FV) then current that flows trough diode is nominal current. When you increase input voltage, current increases and vice-versa.

Laser diodes can't work on nominal current when we connect it to nominal voltage. Because current increases to value that is much bigger than nominal, and diode dies.
If we give 4.5V to BR laser diode current must be limited with current regulator.

That is why we use drivers. To limit current.

Right?

Eudaimonium · May 25, 2010

ReNNo said:
Just a second...
LEDs don't acts the same as laser diodes.

If you connect LED to its nominal voltage (FV) then current that flows trough diode is nominal current. When you increase input voltage, current increases and vice-versa.

Laser diodes can't work on nominal current when we connect it to nominal voltage. Because current increases to value that is much bigger than nominal, and diode dies.
If we give 4.5V to BR laser diode current must be limited with current regulator.

That is why we use drivers. To limit current.

Right?

Actually it's the other way around, we supply constant current source to diodes and the diode takes the voltage it needs from the regulator.

Also, PHR diodes are around 4.8 - 5 V, not 4.5.
12 x diodes at 420 mA are even as high as 6.5 V I think.

HIMNL9 · May 25, 2010

ReNNo said:
Just a second...
LEDs don't acts the same as laser diodes.

If you connect LED to its nominal voltage (FV) then current that flows trough diode is nominal current. When you increase input voltage, current increases and vice-versa.

Laser diodes can't work on nominal current when we connect it to nominal voltage. Because current increases to value that is much bigger than nominal, and diode dies.
If we give 4.5V to BR laser diode current must be limited with current regulator.

That is why we use drivers. To limit current.

Right?

Sorry, but i have to correct you.

Leds and LDs acts in the same way (not for the emission, ofcourse

) ..... both them are light emitting diodes, both of them are, basically, diodes junctions with a voltage threshold (VF), both of them works in current ..... the reason for which you put a resistor in serie to a led, is for give it a certain current, based from Vpower and the resistor value ..... otherwise, you just burn them, like LDs ..... only, LDs are much more sensitive and delicates ..... i had high power IR leds from HP, that i overdrived til the small filament that connect anode pin to the chip becomed dark orange incandescent, and when i left cool them, some of them was still giving out IR ..... LDs just die much much before this, if you try the same

Need help finding PHR-803T diodes for NASA

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lasersbee

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