Telescope Cooling Fan
The images below are of a rear fan that I made for my telescopes tube and then a power supply to power that fan and my mounts drive. The fan and power supply are parts I scavenged from an old external drive case I had laying around the house that wasn't used anymore. The drive case contained two power supplies inside each providing two 12VDC power. This was an excellent power source for my mount drive since it's maximum power is 12VDC and the same went for the fan.
Click on the picture to see a larger version.
| Here you can see the external drive case as it appears without its cover. In the top you can see the two power supplies. I used only supply for this project. I'm sure I can find a use for the other someday. |
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| Here you can see the power supply mounted on the back plate for the box housing my project. Also attached is a small fan that well be used for cooling the supply and then two POTs that well be used for adjusting the voltage put out to the tube fan and mount drive. |
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| Here is another picture from a different angle and closer that shows the supply and wiring. |
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| Another close up shot showing the POTs and small cooling fan. |
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| Here is a picture of the project box. On the top in the left corner you can see my power switch, which is illuminated when on, most cool. In the right corner on the bottom are the two holes for the plugs to which the cords to the tube fan and mount drive well plug into. Also on the right toward the side are the two holes for the POTs. In the middle you can see the bigger hole for the small cooling fan. |
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| This is a picture from the opposite side from the above picture. This shows the hole made for air circulation. The small fan on the other side well blow outward thus sucking air in from this hole and circulating through the box. |
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| Here is everything completely wired up and tested. Now time to assemble the box. |
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| And finally the finished product. You can see the small fan on the side, the two knobs on the POTs, the two connector receptacles, the power switch and the power cord coming out from the bottom. |
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| Here is a picture of the rear telescope tube fan I made. The circle is cut out from some light weight wood. The three strips on the side are Velcro with the opposite connectors on the side of the tube. The cord used was an old 1/4 stereo headphone extension cord. The fan is centered in the middle so it well blow directly on the center of the mirror. I'm going to experiment with this configuration as I'm not sure if blowing onto the mirror is better or should I have it sucking the air through the tube which might provide a more stable even temperature throughout the tube. My goal with this was to provide better cooling of the primary mirror. |
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| Here is a picture of the inside of the fan plate. As you can see it's painted flat black to try and cut down on reflections within the tube. Also the grey area on the outer rim is door insulating foam I picked up at WalMart. The idea here is that it would act as a cushion to help absorb any vibrations from the fan. The good thing is there are hardly any vibration from the fan is it runs very smoothly, but when your doing CCD work any little vibration can be observed so better safe than sorry. |
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| Here is an image of the fan connected to the power supply I built. |
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