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Edocecrous
07-29-2003, 08:58 AM
Hi!

I'm about to install an extra 12V 0.12A FAN into my UTV, and i was wandering, where is the best part to get the power from.

- From the original Fan power connector (so there will be 2 FAN hooked up parallel)
- From the Drive connector
- USB connector
- Directly from the power supply board (i'd prefer this method, but not sure where's the 12V on it.)

Also, i would use a variable resistor to set the optimum speed/noise level, the max power will be 12V*0.12A=1.44W,
so a regular 1.5 or 2W resistor is fine?
Or i need to go with a FET (Field Effect Transistor) and a small variable resistor?

Please advise!

Edocecrous

ps.:I DID searched the UTV forum for this topic, and could not find answer.

klassic
07-29-2003, 10:21 AM
Hi...
check out www.avsforum.com and goto the UTV forum.

Search for cooling there...there has been lots of threads.

Most people (and me) use a CyberCooler (laptop cooler) that connects to the UTV's USB port for power....works well and is about 25$

Warning about AVS.. it is not a hacking site...watch your questions.

apn64
07-29-2003, 01:20 PM
I just hooked-up a couple of internal fans to the existing HDD power connector, and everything is running fine.

You could also splice into the existing fan connector, but it may be current-limited and the wiring will look like sh**.

USB is another alternative, but it's also likely to be current-limited, and you have to route the wiring from the outside to the inside of the box.

I installed a low-profile 7cfm fan over the existing side vents (near the power supply), sucking air out of the unit. I also straddled a CPU cooler (heatsink/fan) over the two tuners. WebTV chip heatsinks were left intact.

Finally, if your 12V/0.12A fan is connected in series with a resistor, it's going to draw less current (spin slower), and consume less power than in standalone. You're better off looking for a lower-speed i.e. less noisy 12V fan with a useful cfm rating. I picked mine up for $3 at a local electronics supply store. The CPU cooler came from an old computer.

GL!

be18driver
07-30-2003, 07:17 AM
Take a look at my thread " A chilling tale " in the DirectTV Tivo Hacking section here. I did just about the same thing to my RCA ultimate box. It was much easier than doing my Tivo box and I used the HD power connector for the fan. I have gotten some flack about using it as an exhaust fan so use your on judgement on which way you want the air to flow. I figure that no matter which way you mount the fan it is better than setting it up on bottle caps as recommended by some owners.

ucpho
08-08-2003, 12:07 AM
What about a hdd cooler?
I noticed that there is plenty of room for that.
Keeping the hdd cool would increase it's life.

apn64
08-10-2003, 09:39 PM
Originally posted by ucpho
What about a hdd cooler?
I noticed that there is plenty of room for that.
Keeping the hdd cool would increase it's life.

Is that really any different than the factory-installed fan that blows on the UTV HDD?

My unit's been running for a couple of weeks with the new mods. The case still gets warm, but I've not (yet) seen any instances of what I suspect is heat related "tuner-fade".

I've noticed that most of the heat comes from the power supply, (obviously a bad design!), and they're trying to use the lower part of the case as a heatsink (did nobody tell these guys that heat rises?), which leads to the tuners getting hot.

Since installing a CPU cooler on the tuners and a fan near the front of the power supply (blowing out, and I can feel the heat), the part of the case directly above the HDD is barely warm at all, so in my case, additional HDD cooling may not be required.

klassic
08-10-2003, 10:19 PM
Actually it's the LNBP13 chips that are attached to the large heat sink on the bottom of the board that are developing the heat....

The power supply is a board of its own.

I totally agree "heat rises" and there could of been a better design to disapate the heat in that area.
But "they" are highly paid engineers...maybe we are wrong and it is fine..... :confused:

I think a CPU style heat sink across both LNBP13 chips with a fan attached would have done a way better job than the heat sink on the bottom....... but what do I know :rolleyes: