Cold cathode stuff......
Those of you following the build know that I've had a cold cathode tube in the Helix reservoir for awhile now. Cold cathodes are crazy bright. A few weeks ago I was wondering whether or not I could hook the inverter power to my FC8 so that I could not only turn it off when I wanted...but also dim it. There was mixed success from folks trying the same thing when I was searching for information online. But I thought I might as well give it a try.
First....this is the cold cathode inverter I've been using. It's made by mod/smart.
I bought this one instead of the standard blue box...because I thought this was better looking, and also because it was modular. You can connect multiple inverters together from only one power source. While that sounded neat....the possibility of me having more cold cathodes in this build is non-existent....so it was a feature that I never used. Anyway....I'm here to tell you today that this pretty black cold cathode inverter from mod/smart......CAN NOT BE HOOKED UP TO SOMETHING PROVIDING LESS THAN 12 VOLTS. When I first tried...I heard a little phizzle...and then the smell of burnt electronics. Lucky these are cheap (around $10 bucks or so). So I ordered another one of these black mod/smart inverters....and tried again.
Same thing. As soon as anything less than 12 volts was applied...it phizzled and burnt.
Since I knew some people had successfully undervolted their inverters....I decided to try the standard blue box inverter...shown below:
These blue boxes are less than $5 bucks. The pictures below compare the size of the black from mod/smart, and the standard blue box. The blue box is narrower, but longer.
So I made a quick power harness that used the two little cold cathode pins on one side, and a 3pin fan connector on the other, and plugged the inverter into my FC8 fan controller. VIOLA! This inverter works fine when undervolted. Now...even though it works, I have to caveat it a little bit. I had two goals really. One....be able to turn the cold cathode off. Done. Two....be able to dim the cold cathode. Done....sort-of. It's real touchy on dimming it. If you start from zero volts and slowly start turning up the voltage....you get a dim light that starts at the bottom of the cold cathode tube and starts growing and spreading to the top of the tube. Once it gets to the top of the tube....it then instantly becomes full brightness. There is just a little bit of wiggle room....somewhere between 9 and 10 volts....where the cold cathode tube will stay fully lit all the way to the top....but not full brightness. So...it works....but it's touchy. It's very easy to have a dim partially lit tube.....but more difficult to have a dim fully lit tube.
But even though it's touchy....I now have options. On/off and bright/dim. Options are always good.
So the next step is to make this ugly blue box prettier. Lots of options....but I decided to have some fun with carbon wrap. I cut a piece of white carbon wrap in the approximate size of the box.
Got out my trusty little purple heatgun, and went about shaping it to the box. Not bad! Now...I don't think anyone is going to ask me to do a full wrap of their car or anything after seeing this....but it looks much nicer than it did before. I'm happy with it.
Next I used a safety pin to pierce the carbon wrap where the vent holes were on the top of the inverter.
Then I used an exacto knife to cutout the openings for the power cords...
Then I used my white MDPC-X sleeve and heatshrink on all the wires to finish it up.
To secure it in the box...I opted for some white velcro....
And here is what it looks like installed in the box. I put it on the PSU side of the case, on the middle wall...tucked up behind the SDD cages.
This shot is full-daylight....but you can still see the cold cathode tube glowing brightly. They are really really really crazy bright. The LED's in the OU reservoir don't show much in the day. I'll probably turn the cold cathode light on during the day....and then at night I'll either dim the cold cathode or turn it off....so that the OU reservoir lighting shows.
I think redoing my SATA power cable is next on my list....along with an attempt at some cable sewing.