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I've come by a few older stereo speakers and would like to use them to start building a decent surround sound system. The idea is to get a good surround sound receiver to drive them, acquire a center channel speaker from somewhere and then upgrade/add-on to these older speakers as funds permit. Pic related; the older, smaller speakers I've found. Source; google.
My problem is the speakers are quite different. While both pairs are 8 ohms their maximum wattage ratings are pretty different. The ones pictured here, Pioneer CS-66G's, are rated at 40 watts max. My other pair, Pioneer CS-903's (pic to follow), are rated up to 300 watts and recommend 70 watts for average performance.
Since I've never had a real surround sound system before how would I go about balancing this out so I don't blow the 66G's apart but still get good volume for the 903's? Do I even need to worry? Finally, is their any quick and dirty method of selecting a center channel speaker other then testing it with my system?
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I'm building a housing for a single board computer + hard drive. As the CPU can get hot, it needs ventilation. But I wish it not to get dusty. So:
What DIY trick / material can be used to filter the dust?
Currently I'm considering tulle fabric / thin PC chassis air filters, but none of those seems suitable.
For the housing I'm going to use acrylic glass, so I'd prefer a material looking better than those black PC air filters.
Also, I fear that due to passive cooling, even with chimney effect, the draught is too low to force the air through.
I'm planning to mount the filter to the top of the box, which happens to be a acrylic glass sheet that'll get a mesh of drilled holes soon. The bottom of the case stays open, that'll do for the air intake.
help repairing ASUS MeMO 7 Micro USB charger port
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Hey. this may not be the best place to post this, but i need some help sorting out a problem with my ASUS MeMO Pad 7 ME170CX-A1-BK
I plugged it into the charger a few moments ago and, just as i did, it slipped from my hand, and instinctively lashed out to grab it. I caught it, but in doing so, i bent the micro USB plug in and also the connector inside. it will still charge, but i have to flex the charger cord to an uncomfortable position and keep it there manually to keep it charging.
I managed to safely detach the back plate on the tablet and can now view the components, BUT the android micro USB port is on the inside of the of innards, sandwiched between the circuit board and the screen. There are screws holding it in place, but before doing so, i need to google if it's safe to remove without causing much irreparable damage.
I cant post pictures, because sadly this was the only means i had of taking them, but i can post a picture of the exact model in pic related. I'll attempt to search for an internet pic of my model with the backplate removed.
I also searched the web for the same issue as mine, but to no avail, so I've come here as a last resort.
The best way i can explain it is like this: To get the device to charge now, I have to bend the micro USB cable toward the screen, not toward the circuit board on the back. Is this a simple case of pulling unscrewing the circuit board from the base and carefully bending the adapter port back into postion? the actual adapter itself seems to have suffered no bending out of shape.
Any questions you have I can answer to the best of my abilities, i deeply apologize for not being able to take pics, this is my last resort before moving on to calling a tech support pain-in-the-ass, although i feel i'm being one myself.
Pic related is my model of ASUS MeMO 7
Building a Space-Shuttle Replica
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Hey /diy/, I'm looking to build a large, replica space-shuttle orbiter module to potentially hang from the ceiling of an arcade. My first and foremost concern is in regards to what sort of materials I should use for the inner frame and the outer shell respectively. The replica will be roughly 12ftx7ftx5ft, and I'm looking to keep it relatively low-cost. My main concern, however, is that I need to know what materials would be the most lightweight, but also the strongest for this application. It's just a simple display piece, meaning it won't be holding people, or anything like that, but it needs to be of relatively sturdy construction, in the event that we perhaps opt to add a few electronic effects to the rig.
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DTMF (Dual-tone multi-frequency) can send a symbol.
The symbol can be 0,1,2,3,4,5,6,7,8,9,#,*,A,B,C,D (16 diferent symbols)
16 symbols = 4 bits
Whats the fastest I could send DTMF tones over an Analog Radio?
So far, there is this site where it says you could send 20/5 ms tones. 20 miliseconds tone duration and 5 miliseconds pause.
It sounds like this: http://www.genave.com/audio/dtmf-genave-superfast-20-05-1646347904.wav
Assuming that is correct, I could send 40 symbols per second. That's 20 bytes per second.
Since this channel is unreliable, I must also add some sort of Forward Error Correction (Redundancy, Hamming or any other FEC), so this will reduce those 20 bytes per second to something near 15 bytes per second.
I chose DTMF since there are a lot of libraries to encode (just send tones) and decode (Goertzel algorithm), but is there SOMETHING ELSE?
I alredy own like 50 analog radios, and there is no digital comunication between. I want to send "documents" as long as 500 bytes. The longest document I will ever send will be 1 kilobyte. It would "theorically" take 51.2 seconds to send 1 kilobyte over DTMF without any sort of error correction algorithm, this is WAY to long.
What else is there?
I have read there is 1200 bps using FSK, but so far I don't see any documentation on it. Which frequencies could I use and so on.
Also, I can't use anything that uses PSK or QAM, since I am using an acoustic coupler, and the phase can change with any small vibration on my device.
I want to make my own acoustic software modem, but I want something faster than DTFM @ 40 symbols per second.
It needs to work over crappy analog radio, using an acoustig coupler (aka, putting my device near the speaker)
I will be implementing this on pretty slow WINCE terminals with .NET