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George Herold
Guest
Thu Aug 26, 2010 7:24 pm
On Aug 25, 2:40 pm, Jon Kirwan <j...@infinitefactors.org> wrote:
Quote:
I've stayed completely away from driving the higher powered
white LEDs, so far. But I'm interested in playing with some
various boost driver designs of mine made from spare parts I
make out of dead CFL lamps (it's fun to do) and I'd like to
buy an "interesting" collection of roughly-1W category white
LEDs for testing purposes. Right now, I don't have a single
LED that requires more than about 100mW to drive.
I expect to buy perhaps a couple of dozen LEDs to make up a
'representative' variety that hobbyists are actually using in
practice. But I'd like to add some interesting types, as
well. For example, some with ball lenses in front. I only
want to test with singles -- none of that 'tristar' stuff.
(Probably, the 1W range limits that, anyway.) Operating
currents in the 350mA to 500mA should be the bulk, but I also
want to buy one or two 1A LEDs, just to play with. I also
want to include a few at the extremities of color
temperature, but the bulk should be in the 5500K-6000K range,
I think. (I'm ignorant of what is going on in that area, so
advice here is also good.) I'd like to get picks from
various manufacturers, too. And based on various
technologies and phosphors. I'd like to stay with ones that
are known to last -- no point testing LEDs that rapidly age.
And I'm concerned about overly complex heat sink situations,
though I won't mind buying premade supplies for that if they
are available, so some advice on this score for some LEDs
that may be SMT and not so conducive to my jury-rigged setups
may help in making selections where the LED is an SMT type
may help me here, too.
Anyway, open to good experiences. Suppliers you've liked, as
well. My temptation is to just buy only what I can find at
Digikey and do the order, that way. But I know that may be
too limiting and so I'm pretty sure I will need to pick these
up from a variety of suppliers.
Thanks very much in advance,
Jon
A colleague used a white LED to replace a flash lamp in a product.
Part number
LXML-PWN1-100. We are obviously just flashing it, but when he ran it
CW it hurt to look at it.
~$2.50 each in quantities of 100’s from Future Electronics.
I think we drive it with only 0.3 to 0.5 amps it claims to be able to
handle 0.7 A.
George H.
John Fields
Guest
Thu Aug 26, 2010 7:24 pm
On Thu, 26 Aug 2010 16:51:06 +0100, Eeyore
<rabbitsfriendsandrelations_at_removethishotmail.com> wrote:
Quote:
Jon Kirwan wrote:
This is a game I play with students to show them what they
can do with junk and a little effort and knowledge.
Might be more useful to show them what they can do *without* using JUNK
! They might learn some REAL design skills.
---
Back again with your never-ending insipid shit, eh?
Just think about how easy it is to learn how to design with everything
in the world available to you, and how hard it is to make things go
the way you want when your resources are sorely limited.
It certainly takes a lot more ingenuity to learn how to make a silk
purse from a sow's ear than it does from the output of a silkworm
farm, but you wouldn't know anything about that would you?
What the fuck are you doing back here anyway?
Trolling for some more of that big Yank cock up your "arse"?
---
JF
Jon Kirwan
Guest
Thu Aug 26, 2010 7:39 pm
On Thu, 26 Aug 2010 16:51:06 +0100, Eeyore
<rabbitsfriendsandrelations_at_removethishotmail.com> wrote:
Quote:
Jon Kirwan wrote:
This is a game I play with students to show them what they
can do with junk and a little effort and knowledge.
Might be more useful to show them what they can do *without* using JUNK
! They might learn some REAL design skills.
I see you've never been a child.
Jon
Jon Kirwan
Guest
Thu Aug 26, 2010 7:43 pm
On Thu, 26 Aug 2010 09:24:05 -0700 (PDT), George Herold
<ggherold_at_gmail.com> wrote:
Quote:
A colleague used a white LED to replace a flash lamp in a product.
Part number
LXML-PWN1-100. We are obviously just flashing it, but when he ran it
CW it hurt to look at it.
~$2.50 each in quantities of 100’s from Future Electronics.
I think we drive it with only 0.3 to 0.5 amps it claims to be able to
handle 0.7 A.
I will take a look. [Though I'm honestly not looking (yet)
to buy 100 of a single part.]
Jon
Jon Kirwan
Guest
Thu Aug 26, 2010 8:02 pm
On Thu, 26 Aug 2010 16:51:06 +0100, Eeyore
<rabbitsfriendsandrelations_at_removethishotmail.com> wrote:
Quote:
Jon Kirwan wrote:
This is a game I play with students to show them what they
can do with junk and a little effort and knowledge.
Might be more useful to show them what they can do *without* using JUNK
! They might learn some REAL design skills.
This coming from someone who thought I needed a capacitor,
didn't notice I needed a resistor, and wasn't sure about
mosfet vs bjt (which is a difference in complexity) for a
project that uses just three parts?
Although I wouldn't imagine to know more than you do about
audio amplifiers, Graham, I know more about this particular
project than you do.
Care to be helpful, rather than critical? Can you offer some
helpful suggestions about LEDs? Or would you prefer sharing
in a little discussion with me about the REAL design skills
involved, where it might help others to see your brilliance
in action?
Jon
default
Guest
Thu Aug 26, 2010 8:57 pm
On Thu, 26 Aug 2010 09:46:34 +1000, David Eather <eather_at_tpg.com.au>
wrote:
Quote:
On 26/08/2010 5:47 AM, Ecnerwal wrote:
In article<ovna7651f35uq5j3k9dmcdtlih9ckgt11a_at_4ax.com>,
Jon Kirwan<jonk_at_infinitefactors.org> wrote:
I've stayed completely away from driving the higher powered
white LEDs, so far. But I'm interested in playing with some
various boost driver designs of mine made from spare parts I
make out of dead CFL lamps (it's fun to do) and I'd like to
buy an "interesting" collection of roughly-1W category white
LEDs for testing purposes. Right now, I don't have a single
LED that requires more than about 100mW to drive.
Well, I haven't played with them yet, but in skimming the pond scum for
interesting parts to add to an order since I was already paying
shipping, I got a few of optek's mini-half-watt series in warm white, as
seeming not too bad on bang/buck and light/watt. I am sort of amused (or
bemused) that their data sheet does not actually connect the cut corner
of the SMD package to polarity...
Those run 180 mA continuous or 350 mA pulsed (10%).
my fav company
www.dealextreme.com also carry a wide range of good
quality (and some more typical quality) high power leds.
I wasn't thrilled with them. I ordered some calipers from them.
Backordered of course. Three months later I finally get them, and in
that time Harbor Freight had them for a few dollars less.
--
default
Guest
Thu Aug 26, 2010 9:01 pm
On Wed, 25 Aug 2010 11:40:24 -0700, Jon Kirwan
<jonk_at_infinitefactors.org> wrote:
Quote:
Anyway, open to good experiences. Suppliers you've liked, as
well. My temptation is to just buy only what I can find at
Digikey and do the order, that way. But I know that may be
too limiting and so I'm pretty sure I will need to pick these
up from a variety of suppliers.
I've had good results with:
http://stores.ebay.com/Shop4leds
I got some piranha style RGB leds and some "straw hat" style 100 ma
white leds - the straw hat ones are at their limit with 100 ma going
through them - one set lasted for a few months (dawn to dusk - fine in
winter dead or dying in summer. Reduced the current to 50 ma and they
are good year round.
--
Jon Kirwan
Guest
Thu Aug 26, 2010 9:22 pm
On Thu, 26 Aug 2010 15:57:28 -0400, default
<default_at_defaulter.net> wrote:
Quote:
On Thu, 26 Aug 2010 09:46:34 +1000, David Eather <eather_at_tpg.com.au
wrote:
On 26/08/2010 5:47 AM, Ecnerwal wrote:
In article<ovna7651f35uq5j3k9dmcdtlih9ckgt11a_at_4ax.com>,
Jon Kirwan<jonk_at_infinitefactors.org> wrote:
I've stayed completely away from driving the higher powered
white LEDs, so far. But I'm interested in playing with some
various boost driver designs of mine made from spare parts I
make out of dead CFL lamps (it's fun to do) and I'd like to
buy an "interesting" collection of roughly-1W category white
LEDs for testing purposes. Right now, I don't have a single
LED that requires more than about 100mW to drive.
Well, I haven't played with them yet, but in skimming the pond scum for
interesting parts to add to an order since I was already paying
shipping, I got a few of optek's mini-half-watt series in warm white, as
seeming not too bad on bang/buck and light/watt. I am sort of amused (or
bemused) that their data sheet does not actually connect the cut corner
of the SMD package to polarity...
Those run 180 mA continuous or 350 mA pulsed (10%).
my fav company
www.dealextreme.com also carry a wide range of good
quality (and some more typical quality) high power leds.
I wasn't thrilled with them. I ordered some calipers from them.
Backordered of course. Three months later I finally get them, and in
that time Harbor Freight had them for a few dollars less.
That was _almost_ my case. My products were backordered for
some time and eventually I decided to send a message asking
what is going on and when the backorder would be released.
More time goes by (month more? that, after a previous 6
weeks of delay) and I get a message about "would you like to
get something else?" Dialog is very slow (language?) and it
took still more time to begin to understand that they
intended to keep the money no matter what and not make it
easy, either, to put it onto some other order. I still don't
know how that gets done.
And, I suppose, I've become less interested in finding out.
Jon
Jon Kirwan
Guest
Thu Aug 26, 2010 9:28 pm
On Thu, 26 Aug 2010 16:01:15 -0400, default
<default_at_defaulter.net> wrote:
Quote:
On Wed, 25 Aug 2010 11:40:24 -0700, Jon Kirwan
jonk_at_infinitefactors.org> wrote:
Anyway, open to good experiences. Suppliers you've liked, as
well. My temptation is to just buy only what I can find at
Digikey and do the order, that way. But I know that may be
too limiting and so I'm pretty sure I will need to pick these
up from a variety of suppliers.
I've had good results with:
http://stores.ebay.com/Shop4leds
I got some piranha style RGB leds and some "straw hat" style 100 ma
white leds - the straw hat ones are at their limit with 100 ma going
through them - one set lasted for a few months (dawn to dusk - fine in
winter dead or dying in summer. Reduced the current to 50 ma and they
are good year round.
Okay. I've often wondered about aging issues. So that's
good to know.
When high power is the primary goal of a product, often other
goals are sacrificed on its alter.
I'll take a look on Shop4leds on ebay, too, then.
thanks,
Jon
Eeyore
Guest
Thu Aug 26, 2010 10:14 pm
Jon Kirwan wrote:
Quote:
On Thu, 26 Aug 2010 16:51:06 +0100, Eeyore
rabbitsfriendsandrelations_at_removethishotmail.com> wrote:
Jon Kirwan wrote:
This is a game I play with students to show them what they
can do with junk and a little effort and knowledge.
Might be more useful to show them what they can do *without* using JUNK
! They might learn some REAL design skills.
I see you've never been a child.
I see you don't realise the disadvantages of use life-expired
components. I bought new parts for the vast majority of my hobby projects.
Graham
Eeyore
Guest
Thu Aug 26, 2010 10:15 pm
Jon Kirwan wrote:
Quote:
On Thu, 26 Aug 2010 16:51:06 +0100, Eeyore
rabbitsfriendsandrelations_at_removethishotmail.com> wrote:
Jon Kirwan wrote:
This is a game I play with students to show them what they
can do with junk and a little effort and knowledge.
Might be more useful to show them what they can do *without* using JUNK
! They might learn some REAL design skills.
This coming from someone who thought I needed a capacitor,
didn't notice I needed a resistor, and wasn't sure about
mosfet vs bjt (which is a difference in complexity) for a
project that uses just three parts?
WTF are you talking about ?
Graham
Jon Kirwan
Guest
Thu Aug 26, 2010 10:46 pm
On Thu, 26 Aug 2010 22:14:20 +0100, Eeyore
<rabbitsfriendsandrelations_at_removethishotmail.com> wrote:
Quote:
Jon Kirwan wrote:
On Thu, 26 Aug 2010 16:51:06 +0100, Eeyore
rabbitsfriendsandrelations_at_removethishotmail.com> wrote:
Jon Kirwan wrote:
This is a game I play with students to show them what they
can do with junk and a little effort and knowledge.
Might be more useful to show them what they can do *without* using JUNK
! They might learn some REAL design skills.
I see you've never been a child.
I see you don't realise the disadvantages of use life-expired
components. I bought new parts for the vast majority of my hobby projects.
Besides the fact that these are kids, Graham, it is exciting
for them to do something useful and fun with parts their
parents throw away. Kind of a segue to more. And it often
impresses their parents, which may for some excite them
towards further effort. And I can always help them at that
point, if they are interested in doing more.
I am on the ground, spending _my_ time in the trenches with
kids, Graham. I am dealing with what I have to work with. If
you'd like to come on over and help out, I'm all for it. And
I'd value your opinion on this more, then, because of your
direct experience with my situation.
What are _you_ doing, Graham, to pass on your knowledge and
interests to children?
Jon
Jon Kirwan
Guest
Thu Aug 26, 2010 10:48 pm
On Thu, 26 Aug 2010 22:15:51 +0100, Eeyore
<rabbitsfriendsandrelations_at_removethishotmail.com> wrote:
Quote:
Jon Kirwan wrote:
On Thu, 26 Aug 2010 16:51:06 +0100, Eeyore
rabbitsfriendsandrelations_at_removethishotmail.com> wrote:
Jon Kirwan wrote:
This is a game I play with students to show them what they
can do with junk and a little effort and knowledge.
Might be more useful to show them what they can do *without* using JUNK
! They might learn some REAL design skills.
This coming from someone who thought I needed a capacitor,
didn't notice I needed a resistor, and wasn't sure about
mosfet vs bjt (which is a difference in complexity) for a
project that uses just three parts?
WTF are you talking about ?
Without the battery or LED, three parts. You didn't follow
and I guess we can leave it there, then. :)
Jon
John Fields
Guest
Thu Aug 26, 2010 10:51 pm
On Thu, 26 Aug 2010 22:14:20 +0100, Eeyore
<rabbitsfriendsandrelations_at_removethishotmail.com> wrote:
Quote:
Jon Kirwan wrote:
On Thu, 26 Aug 2010 16:51:06 +0100, Eeyore
rabbitsfriendsandrelations_at_removethishotmail.com> wrote:
Jon Kirwan wrote:
This is a game I play with students to show them what they
can do with junk and a little effort and knowledge.
Might be more useful to show them what they can do *without* using JUNK
! They might learn some REAL design skills.
I see you've never been a child.
I see you don't realise the disadvantages of use life-expired
components.
---
Don't you mean: "of using"?
But, in that vein, why would an Allen-Bradley carbon comp resistor
made in 1945 not work now, and perform to spec.?
Or, for that matter, a 2N2222 made a dozen years ago?
---
Quote:
I bought new parts for the vast majority of my hobby projects.
---
Bullshit.
You bought what you could get, and whether they were "new" parts was
the least of your concern.
---
JF
Jon Kirwan
Guest
Thu Aug 26, 2010 11:02 pm
On Thu, 26 Aug 2010 16:51:35 -0500, John Fields
<jfields_at_austininstruments.com> wrote:
Quote:
On Thu, 26 Aug 2010 22:14:20 +0100, Eeyore
rabbitsfriendsandrelations_at_removethishotmail.com> wrote:
Jon Kirwan wrote:
On Thu, 26 Aug 2010 16:51:06 +0100, Eeyore
rabbitsfriendsandrelations_at_removethishotmail.com> wrote:
Jon Kirwan wrote:
This is a game I play with students to show them what they
can do with junk and a little effort and knowledge.
Might be more useful to show them what they can do *without* using JUNK
! They might learn some REAL design skills.
I see you've never been a child.
I see you don't realise the disadvantages of use life-expired
components.
---
Don't you mean: "of using"?
But, in that vein, why would an Allen-Bradley carbon comp resistor
made in 1945 not work now, and perform to spec.?
Or, for that matter, a 2N2222 made a dozen years ago?
---
I bought new parts for the vast majority of my hobby projects.
---
Bullshit.
You bought what you could get, and whether they were "new" parts was
the least of your concern.
---
JF
Maybe Graham is just saying he was born with a silver spoon
in his mouth. But I really think it is his failure to
actually remember what it is like as a kid looking in, from
the outside.
I didn't do much as a kid -- instead spending far more time
on optics, explosives, rocketry and the like. Some others
did and they eventually made career decisions and left me far
behind in this regard. But I've always had a kids interest
in electronics, as a hobby. Never had a single hour of
formal training in it, though.
But I remember vividly building my first radio out of galena
and molten lead, with a sewing needle, to make the diode. And
all the rest involved, too. And making a jacob's ladder from
a TV flyback supply. And calling up a bowling alley owner
for permission to scavenge what I could from his building
after it was hit by a tornado the day before, for parts. And
tearing apart phone company throw-aways I'd get out of a
dumpster behind their building. Etc.
I had no money, lived in a home without walls at the time,
and had to get by without a lot that some living in better
circumstances had access to.
It's possible that Graham has no idea about any of this and
had everything pretty much handed to him.
Jon
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