8X Diode Murder fund

you all are right of course!
i more or less meant that now, with the 8x diodes, it is the first time we solely rely on working drives as a source. in the other cases we used both, sleds and drives (first?), so it now would be difficult to find out if drives' diodes all are consistent and efficient..

i wonder if there will be sleds any higher than 6x drives.. maybe the diode producers have their production lines all working now, so they start selling working (non-"prototype"-) diodes right away?

yes, igor, i was referring to your hypothesis! hard to keep track where i read what, for me too. so many threads!

manuel

Hallucynogenyc said:

wasn't people buying the xbox readers too to get the phrs? xD

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Shortly after the big money spent on the 2X drives, and also Lava's and Mike's first 6X's, we found out about the cheap PHR's.

I remember wishing that I didn't spend the money on the 2X drives...

All of them start out with us buying drives. Sleds come later.

Peace,
dave

Is the V5 flexdrive going to be adequate as a driver?

T_Warne said:

Is the V5 flexdrive going to be adequate as a driver?

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They seem to be, so far.

Peace,
dave

That is encouraging. I already bought one just for this diode.

What are the rest of you planning on using? :thinking:
Which host?
What heatsink?
Who's driver?

T_Warne said:

That is encouraging. I already bought one just for this diode.

What are the rest of you planning on using? :thinking:
Which host?
What heatsink?
Who's driver?

Click to expand...

Host: Kryton Groove
Heatsink: Kryton Groove
Driver: Igor's

Rominsen host and IgorT driver & v3 heat sink for me... -Glenn

Romisen host, v3 sink, IgorT driver for me.

Host: DX TR-801 14.56$
It uses an 18650 cell, there is another one for CR123A: TR-803 14.27$

sink: copper soldered into the hosts' head

driver: flexdrive

manuel

which lens are you guys gonna use?

im gonna have one of Ehgemus's custom RPL style hosts for the host/heatsink, then as Igor is doing the build for me he is going to use one of his drivers...cant wait...

hopefuly goin to use one of IgorT's lenses also...:san:

Krutz said:

that is not possible by just two watts from the diode. what driver and battery configuration are you using? i repeat, 2 watts is just laughable, by normal standards

manuel

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I won't say laughable, but i still have to agree....

To test how an 8x would behave in Jay's CR2 Keychain host, i put a LOC at 525mA in...


The heat dissipation is 1.36W. I left it on for half an hour! It was hot, but not too hot to touch.. And definitelly far from a temperature in any way dangerous to the diode.


Of course 2W is a lot more, and the extra 0.64W more would be very noticable in the same host, unfortunatelly i have no diode to simulate this, but keep in mind this is a keychain host with a tiny heatsink, where most of the heatsinking is done by the body.


BUT! In AA host or CR123 models i played with, either with classic AixiZ-mounted heatsinks, or CNC machined heatsink/modules, i wouldn't be worried about 2W... I did 60min power stability graphs at just over 1W heat dissipation with AA models, and at the end the laser was still at body temperature!

I know that twice the heat doesn't mean half the time, but less, but i still wouldn't think that 10 or even 20 minutes would be a danger for the diode.

I've never seen a laser that was too hot to touch, regardless of how small it was or how long i left it on.


Larry:
What kind of driver was used in that big flashlight? Since the host seems to have several batteries, is it a linear driver or a buck driver?

Also, what was the 2W heat source? What kind of LED or LD? Current, Vf (Po?)?


I was trying to figure out how to emulate 2W of heat dissipation, since no diode i have is capable of creating that much heat and surviving. But maybe a dead diode would do...

Dead diodes drop in Vf somewhat, so the current might have to be increased,, but it might just be possible to do unless the diode becomes a short....


I could try to record a temperature graph with calibrated SMD thermistors soldered to the diode directly..

Igor;

My experience on heat dissipation is from hundreds of LED lights that I have built.

The ones that best illustrated heat dissapation issues were 3 watt UV LED's generating 2 watts of heat. They were driven from modern 90% efficient switching regulators that were remote to the LED's.

The LEDs were mounted on commercial 1.5" high Thermalloy heatsinks that were similar to this type:

They have much more surface area than most hosts, and are black anodized aluminum.
Temperatures at the horizontal mount surface (measured with an IR thermometer) climbed from 30° C to 80° C in ten minutes.
This is the contolled temperature that diode manufacturers maintain when testing CONTINUOUS power levels.

Obviously, we cannot expect good life at these temp levels if we are driving the diodes at 2X or 3X these power levels.

What operating temperature at the diode, do you think is acceptable for 10 minutes of continuous use ?

I'm just trying to caution people from long operating cycles with small hosts.

LarryDFW

LarryDFW said:

I'm just trying to caution people from long operating cycles with small hosts.

Click to expand...

This is why we need more Kryton orders

It seems many people overlook heatsinking.