Daedal Driver with Blueray?

[ElektroFreak]

[quote author=ElektroFreak link=1228366500/0#14 date=1228616133][quote author=randomlugia link=1228366500/0#13 date=1228608384][quote author=ElektroFreak link=1228366500/0#7 date=1228450850]If you want it to last more than 20-30 hours, keep it BELOW 100mA. I keep all mine at 75mA. There's a lot of hype about PHRs, but the bottom line is they're only reliable up to about 60-70mW. Above that, and you're looking at imminent failure.

I would have to disagree. If you have it heatsinked well enough, then it could last a long time at 110mA. Without a heatsink, stay below 100mA. But I really think it's worth the money buying a good heatsink, or if you're chep like me, just super glue some 12mm washers.[/quote]


I only use blu-ray diodes to build lab modules for laser display purposes, and I use these huge heatsinks from z-bolt.com: http://z-bolt.com/MODIIIbg-green-laser-module.html(they're listed under the three green modules..) PHR diodes will work at 110mA, but not for anywhere near their rated lifetime. They're supposed to last up to 10,000 hours. You'll never see anything like that over 75mA, and maybe even not then.. [/quote]


None of the diodes we use last for their rated lifetime, Long open can diodes are a good example, most people drive these at 420mA , producing 270-300mW. Do you think they will last 10,000hrs ?

There are 180mW BRs driven at 170-200mA that use 803T diodes and they are still going strong. A good example are some of Daguins BRs , they have lasted months.

-Adam

[/quote]
Fair enough. I'm an electronics engineer, so ingrained in my psyche is the desire to over-engineer. Reliability is a huge concern for me, and I consider a laser useless if I don't even have the option of using it continuously for years on end. In a laser show environment they sometimes stay powered up for hours on end depending on how long the show is. Modulation helps ease the strain on the diodes, but I'm pretty demanding nonetheless. I've been working on building a cheap RVF (Red Violet Fuscia) scanner, and I'd like to use a homemade module containing a PHR, but until I'm sure that it's MTBF will be at least 2000 hours, then it's not a viable option. Buying violet lab modules commercially costs thousands.. I'll be continuing my research into PHR (and other violet diodes) longevity in the interests of saving money, but these are the reasons I feel the way I do about current and PHR lifetime..

 

[daguin]

If you are going to use a PHR diode in a laser show, construct the show so that you can replace the diode regularly.  It should also be constructed to change the diode quickly if you are entertaining friends or the public AND you should have several on hand.

You may want to look at buying a 6X burner drive to harvest the diode out of it.  They will survive better than the PHR.  Of course you are swapping longevity for dollars (PHR=$15 -- 6X=$285 :: one 6X = 19 PHR's)

This is one of the reasons I don't mind pushing these PHR's so hard. I can replace the PHR 19 times before I equal the cost of one 6X. With the costs of the current PHR's (salvaged) I can replace the PHR diode about 25 times In a well designed pointer replacing a diode is not much of a problem. However, in a laser show, the replacement time and timing of the diode's failure is a much more central issue

Peace,
dave

 

[ElektroFreak]

If you are going to use a PHR diode in a laser show, construct the show so that you can replace the diode regularly.  It should also be constructed to change the diode quickly if you are entertaining friends or the public AND you should have several on hand.

You may want to look at buying a 6X burner drive to harvest the diode out of it.  They will survive better than the PHR.  Of course you are swapping longevity for dollars (PHR=$15 -- 6X=$285)

Peace,
dave

Also a good point, but I'll counter with the fact that I don't have to worry about quick-changing my other modules (but I still keep backups of each just in case). I'd very much like to find a combination of diode andpower that is absolutely as reliable as my other commercial modules, and I think it can be done. A 6X would stand up to the abuse better, but right now I'm on a serious budget. This is my own private project and I just became a father for the first time, so money's a bit tight right now.. My research on them will have to wait.. For now, all I really need is about 50-60mW of violet light, and I haven't given up on PHRs just yet.

 

[Alexizupinhea]

Umm, so I have a question. Will 2x Cr123a rechargable 3.6V batteries work for a PHR-803t using ddl's circuit (they produce 8V max when fully charged, but will go down to lower voltages relatively quickly i would assume)? Also, is the circuit any different in terms of blu-ray vs. red burner (ex. any different resistors)? Thanks in advance for any advice.

Edit: Also, if I make washer heatsinks for each (red and blu-ray), what mA would you recommend for each? I would want both to last for at least a year or two. From what i understand, there comes a point where increases in mA produces quite small increases in mW, so what would you guys recommend and approx. how much mW would it produce?

 

[ElektroFreak]

If I were you I'd use three Cr123a cells. It will push more than the recommended 9V, but the LM317 will regulate it to the proper 5V. LM317s can take a wide range of voltages on the input, but the circuit needs at least around 9V to provide enough voltage and current to the PHR. Red diodes, on the other hand, do great with just two Cr123a cells. The LM317 circuit configured for red diodes only requires around 7.5V of input. The difference is in the resistors.A typical blu-ray circuit has a 10 ohm resistor in series and the red diode circuit replaces it with two 10 ohm resistors in parallel, which actually equals a 5-ohm resistor capable of handling more current than just one resistor by itself could. Basically the lower the resistance, the more current the circuit can provide.

As far as heatsinking, before I can answer that properly I need to know if you're using the diodes in pointers or freestanding lab-style modules.