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can i replace Nichia NDB7A75 with a Sharp GH04C05B9G

GravityRZ

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question regarding wattage
the NDB7A75 does 3.5 watts with 3amps and voltage around 4.7
the GH04C05B9G does 5 watts with 3.5amps and voltage around 4.8

even if the voltages are not 100% correct things do not add up

can we say the sharp diode is more efficient(and thus creates less heat/amp)
 



Alaskan

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question regarding wattage
the NDB7A75 does 3.5 watts with 3amps and voltage around 4.7
the GH04C05B9G does 5 watts with 3.5amps and voltage around 4.8

even if the voltages are not 100% correct things do not add up

can we say the sharp diode is more efficient(and thus creates less heat/amp)
GH04C05B9G



Nichia NDB7A75

 
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GravityRZ

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you attached the wrong info i think.
anyway, looking at those specs i notics that the 7A75 specifies 3.6 watts with an If of 2.3, at 3Amps it is probably doing more than 3.6 watts
 

RedCowboy

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The 7A75 is a better diode, it's stronger or as strong and has better divergence, I don't think it's much less efficient, 5.4W @ 3.5A and the 7A75 does the same @ 4.0A........ however the Sharp 5W dies past 4.0A .......I damaged one @ 4.3A .....it dimmed down @ 4.3 and never was right after that, it still worked but was damaged/weak but the 7A75 is tough and can take a little extra, however it's the divergence that makes the biggest difference......that said the sharp is available at a good price and is new.

 
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Alaskan

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The info might seem wrong because as hobbyists, we push them harder than the manufacturer recommends which reduces their life. I did find a better spec and edited it in for both. My thought was it is best to compare the voltage and currents at the manufacture recommended amounts, otherwise you must know the hours they last at the boosted levels to make a reasonable comparison.
 

GravityRZ

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The 7A75 is a better diode, it's stronger or as strong and has better divergence, I don't think it's much less efficient, 5.4W @ 3.5A and the 7A75 does the same @ 4.0A........ however the Sharp 5W dies past 4.0A .......I damaged one @ 4.3A .....it dimmed down @ 4.3 and never was right after that, it still worked but was damaged/weak but the 7A75 is tough and can take a little extra, however it's the divergence that makes the biggest difference......that said the sharp is available at a good price and is new.

now that's good info.

i rather buy a diode which can take a hit then one which can be killed easilly
 

Lifetime17

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Hi Red
Thanks I posted earlier this morning no coffee and one eye open
I agree the ndb7a75 is an awesome diode I have them can’t beat them
I prefer them over the nubm44 any day
Rich:)
 

RedCowboy

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The 7A75 by itself is a good one no doubt, however with the right optics the 44 is just more laser.....let me explain.....the 7A75 with a G2 makes a bar 1.25 inches long at 15 feet and a 44 with a G2 makes a bar about 1.75 inches long at 15 feet so both do a little over 1 watt per 1/4 inch of bar at the same distance with the same lens ( G2 ) which lets all the light through......actually the 7A75 is slightly more energy dense given it's better divergence

A good 7A will do 6W and a good 44 will do 7.5W so 7A=1.2W per.25 inch and 44=1.1W per .25 inch.......7A = 1.2 vs. 44 = 1.1

However if you are using corrective optics then the 44 is the way to go, but for a simple single diode build with a single coli lens the 7A75 makes a better looking beam that ends up being a little more energy dense but has less total output.......I have been hoping Sharp or Osram would put out a nice 10W blue with 7A75 or better divergence, sadly the 5W Sharp is not the one I am hoping for.
 
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