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ArcticMyst Security by Avery

FREE DIY open source BOOST driver!!! Tested & working!!






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Oh gosh I need a day off to read that proper... or play with it... I think my building electronics day's are numbered... I want something more like this...

7016-duno.bmp




RHD is there a board to go on my arduino nano for the ophir? I dont really care how it is powered I would like to try and test one.
 
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Blord

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I have modified mine a little bit. Adding grappling hooks and alligator clips is much easier to work with and no soldering is required attaching to the driver.

the red wire has also a grappling hook but it just broke off before the picture is taken :eek:
testload3A-1.jpg
 
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benmwv

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From my experience using regular round resistor isn't a good idea. You can't heatsink them well and when they heat up their resistance changes. When the resistance changes your voltage reading changes, so you are measuring the wrong current. In my test load I used a to-220 resistor on a nice aluminum heatsink to counter this. The resistor says plenty cool and my readings don't drift.
 
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From my experience using regular round resistor isn't a good idea. You can't heatsink them well and when they heat up their resistance changes. When the resistance changes your voltage reading changes, so you are measuring the wrong current. In my test load I used a to-220 resistor on a nice aluminum heatsink to counter this. The resistor says plenty cool and my readings don't drift.

That is interesting.

It is a 5 watt resistor though. Is it heating up very much?
 

Blord

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I didn't know that too. I suppose it will do the job to 3A. I do smell a burning odor when leave it too long. :)
 
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I wouldn't trust it to 3A. It's only rated to approximately 2.2A through it... I^2*R is the power rating.

I wouldn't even touch above 2A.

Hell - I was using a 10W resistor on my home-grown one, and I don't like running it above 3A.
 

Hiemal

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I don't understand why we don't just get an amp meter of some sort and just measure the current the right way. That way you can omit the resistor entirely and just rely on what the driver outputs, not what the resistor tolerances are.

Just my thoughts.
 
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Because it would be more expensive :p And, using the Vdrop from the resistor makes it easier to measure high-power LDs without 9 diodes =p
 

benmwv

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I don't know exactly what resistor is used in those loads, but I tested a few different high wattage resistors at high current (around 2A) and they all warmed up and the resistance changed a bit when they got hot.

At 2A you have 4W, at 3A you have 9W so it's definitely gonna be getting pretty hot. If the resistor is high quality and good tolerance then it shouldn't change much within its rated range, but I like to have plenty of breathing room. The resistor is the most important part and I think it should definitely be heatsinked.

Edit: Yes that one looks good.
 
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I really like my test load I just want to increase the number of diodes on it.. that shouldnt be that hard to do.. I'm going to order some more and make an addon for it. I really like the idea of jumpers for adding a diode here and there.. and I have to buy another multimeter to test V and C so I will get a decent one.. Wish Jeff would jump in here but I know he is busy...
 
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OK, I got my scope today. Passes all self tests and to my untrained eye and to some forum members more trained eyes, it looks to be ok.

So... if someone wants to give me a quick walkthrough, I can scope a Mohrenberger BenBoost driver.

I have a TDS210 if that helps.

Let me know what to do, or you'll have to wait until I figure this thing out completely. :D

I'm headed off to YouTube for o-scope lessons.
 




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