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ArcticMyst Security by Avery

WOW crazy blu-ray

Abray

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Ok I have a problem. I don't know whether I fried my blu-ray diode or if it is an extreme freak.

In this story, I am not, in any way, defaming Daedal or trying to blame him for anything.

here's the story:
I got all my stuff straight from Daedal. 2 driver kits and 2 blu-rays preinstalled in the AixiZ modules. I built one, and I find that the pot is EXTREMELY sensitive. It changes almost none at all until you hit 30mA and then it starts going REALLY fast, and you barely have to touch it for it to jump alot of mA. basically barely turning it will make it jump to 120mA. this was all with an LED though, so my first blu-ray was fine! i switched it out and after some very careful tweaking, I got the pot to settle out at 37 mA. I dared not touch it in case it would screw up. Then my dad wanted one, so I made one for him. I got everything set up, shorted the capacitor, and hooked the blu-ray up. I started turning the pot, and it was even more sensitive than the other one, I got to 30 mA and then I applied barely enough pressure for it to be noticeable, and the pot jumped up to 80 mA! I quickly turned it back down, and tried again. Same results. 2 more times, same results. now through all of this, the diode would not laze until it jumped to 80mA. And then at the 80mA, it looks like my other diode at 20mA. is the diode fried? or is it just a freak? I am thinking it is fried, even though that would mean that it would have had to been fried from before I even hooked it up to the circuit. When I hooked it up, the pot was set to a lowly 7mA, so I know it was not immediately fried.

I think it might be fried, but does anybody have any suggestions? comments?
 





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I think that the pot has a really high resistans, way over 100 ohm's. Check it.
 

Abray

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ok. Also, it has that famed yellow box around the dot...
 

chido

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80mA :eek: It's probably dead, but it became a zombie diode. ;D Even though it's dead it can still lase, but only at very high currents and it'll get really hot.
Oh, just looked at your post above, it has a yellow glow around it. It's definetely a zombie diode.
 

Abray

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alright thanks chido :(...

I checked the resistance and when it was turned all the way down, it measured .944 Kilaohms. is that normal?
 
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Yes, that's 100 ohm's. Check all the other components and connections as well. BTW the best way to measure the resistanse on the pot is to do it on the two leggs next to each other, not on the one in the center.
 

Abray

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I did connect botch input legs and the output leg. The curcuit had no faults that I could see. Both of my pots behaved like this. This one to the extreme. It just makes me angry because I just lost alot of money because of a wierd pot. I was supposed to earn about 70 dollars, but instead, I just lost around 30

and can anybody explain the jumping phenomenon? I have asked people before, and they say their pots don't do this...
 

chido

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.944 Kohms? :eek: No wonder it jumps like that, that's not a 100 ohm pot, thats a 1kohm pot. (1000 ohms)
 

Abray

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Is that a joke? I can't tell, lol.

But these pots should be the right type because Daedal sent them to me when I bought his kit(two of them, both with wierd pots)
 
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FireMyLaser said:
Yes, that's 100 ohm's. Check all the other components and connections as well. BTW the best way to measure the resistanse on the pot is to do it on the two leggs next to each other, not on the one in the center.

.944 Kohms is not 100 ohms.  That sounds like a 1K pot (.944K = 944 ohms).  If you're using a 1K pot, it's gonna be very twitchy at its limits.
 

Abray

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I thought so...

its almost 1000 Ohms!!!

and I'm asking everybody who's read this, do your pots steadily rise in resistance(or drop), or do they go very slowly and then very rapidly at a certain point?
 
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sorry to jump in on a topic I'm not certain on, but did you get these pots from the group buy or did you supply your own?

.994k is just under 1000 ohms, not 100ohms... also there's a couple different kinds of potentiometers, linear or... I think "volumetric" is the word, I forget... but "exponential" anyway.. they either go in a straight line from 0 to 100ohms (linear), or they double at each setting, going 2ohms, 4ohms, 8ohms, 16ohms, 32 etc.
you probably want to make sure you're using 100ohm linear pots, though it sounds like you're using a volumetric 1k pot.

edit: ok, I see we've established it's a 1k pot.. never mind, I'm a little slow tonight.
 




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