My first overclock!
Having friends who are hardware geeks is good at some time , but you usually have to try rather hard to win their respect.Its usually easy for a girl to get a geek's attention! but for a geek to say "Now that's cool " to another geek is much, much harder.Now despite me having speakers which blow the socks of anything else, I hadnt quite, whats the word....*OVERCLOCKED* anything.But today , I blog before you, a different man, someone foolhardy enough to throw caution to the winds, and run his device at *drum roll*....not 10%, not 50%....but a whole 100% (yeah thats right!..TWICE ) as fast as it should.technically, it will go upto 8 times , but no one is THAT greedy.The point was,my new mouse , running at 1600 dpi, comes up with a lot more finfo than, say a 400dpi mouse. and for all that info to get across, you need more than the default 125 Hz set for usb devices.Thus it was doubled to 250Hz. i dont want to increase it any more as it seems to be taking up more CPU.but at least there are no stability issues!Compared to a ps/2 running at 200Hz, it aint much, but remember, the PS/2 is an asynchronous connection, while usb is synced check out the screenshots
posted by kickassso, 12:52 AM
The iBall Laser Precise
I finally got my iBall laser precise mouse !. I took it as a risk as I hadn’t read any reviews of it yet, But I’m a fully satisfied dude today, and I want anyone else who might be considering buying it to read this!.showstopp3r is also doing a post on this too!
First of all, given the adequate cash, all of us would like to buy Logitech g5’s or MX 518’s or Razer Diamondback’s…razer’s are not available at all here, and the Logitech’s cost an arm and a leg!(and possibly a kidney too). The choices for a precision mouse in the under 1k range is rather limited to the Microsoft wheel mouse optical. Not any more!
The iBall laser has a 1600 CPI sensor (CPI= Counts per Inch). First , I had my doubts about CPI, fearing that it might be something iBall cooked up to get to the glorious 1600 figure,(like the PMPO ratings we have on speakers)but found the mention of cpi in toms hardware saying that cpi is what actually matters! It’s also got six buttons, which includes a task hotkey and IE forward/backward (also assignable to other keys) buttons. The build quality of it is okay, but the mice feet don’t seem to be of terribly high quality, and the one of the feet of my old iBall had started to migrate a bit! I wish it had at least ONE LED! I was under the impression that being a laser mouse, there would be a cool laser thingy underneath etc…unfortunately all there was is a small hole and a “LASER” hologram. I know it’s just a gimmick, but I wish it had some bells and whistles :D
First of all, the mouse is NOT for lefties…the iBall website claims otherwise though! The feel of the mouse is great, with a matt grips t the sides and is very comfortable to hold. Plugging it into windows, my SP1 XP needed to install drivers before it was recognized as a mouse. The mouse utility was installed separately, and to me, seems more like a gimmick. The hotkey button makes a circular menu which has some apps and shortcuts on them. The only hitch is that they are PowerPoint …Word, etc….none of which I need to use THAT regularly. unfortunately, the app’s themselves could not be changed and I hated that menu…but it did remind me of the stuff I’d seen on some Logitech mice…also , the driver did not have the x-mouse style of scroll activation I used to have on my old iBall! So I uninstalled the v4.5 drivers and installed the v2.2 drivers (intended for the black cat) this cured it, and the fwd and rwd buttons were individually configurable... Only the hotkey on top became redundant, as the black cat didn’t have any! But it still does work as the middle mouse button which is nice, since the scroll wheel is a bit hard to press anyway. Also, the main buttons are a bit hard, but I guess use will loosen em up!
Using it was scary at first, it being very, very sensitive and adding to the fact that it was much lighter than a regular ball mouse, was like graduating from a Hindustan ambassador to a lancer EVO. I couldn’t even handle it! But gradually, I got the feel of it , and now I cant be without it! The buttons help a lot too; I browse and listen to music a lot. I set the back button to default and the fwd button to F9 and used that to set a QCD global hotkey! (I use QCD player instead of Winamp!) Now all I need is my mouse! And I don’t need to get QCD even. But it would have been nice if the drivers had allowed for the next track key to be assigned to that button (like a MM keyboard)
Actual game performance!
The testing of the mouse in CS was delegated to frantic. He opines that the sensitivity is good, and that he got headshots with lesser guns. Unfortunately for me, my CS performance seems to have gone down a few notches with this mouse (or maybe it was because I played CS after a Looooong TD on UT 2004!) but UT 2KK performance is simply awesome!!!!!!!!!!!!!!!!! the rocket launcher, which had been alien to me till now and had been at the bottom of my list went straight to the top and I learnt how to do the much famed “predictive rocketry” usually I play in average skill(heh he …yeah I’m a Noob)but with the new mouse, I got a 25/4 victory over a skilled bot in Idoma I was on a rampage first, going up to dominating!) I ought to try out adept next! First, I was unable to get the extra keys to work but found out that it was because I had left the driver utility running (lwbwheel.exe) end task it and you’re set to game! Remember to start it once you’re back in windows though! I had read that mice would make such a difference in skill, but never such a difference! Anyway, for gaming, this mouse rules! A minor bug (or should I say feature) is that this mouse tracks in the air!! Even up to about one inch in the air, the cursor will still move with your hand! With my habit of moving the mouse and picking it up, moving it again, learned on lower resolution mice, it seemed a minor irritant! But when I’ve got 1600 CPI, who cares!
The mouse is priced at 1990 MRP (yeah right!) and I got it at 875. At that price, it is terrific value for money. The iBall dealers seem to have them ready in stock, so you’ll get them soon! If you want to have a good mouse, but can’t spend K’s of rupees on one, this mouse is what I’d recommend.
posted by kickassso, 9:38 AM
Enhancer Settings
Enhancer is a Winamp DSP plugin which is far better than Winamp's own equalizer.To get the maximum out of any DSP, u need to tweak it to the max, for each song.
I am posting here, a setting which I found ideal for both Trance and Rock (its good to my ears atleast!).
Here we go!
posted by Erosimian, 10:58 PM
Amplifier Distortion!
With time on my hands and no other humans in the vicinity. I finally settled down to test my audio Rig…people test GPU’s, CPU’s so I thought …why not my amp?… why not push it to the limit. And got some interesting results. First of all, you need some heavy metal to help digest the distortion! Try listening to something which was recorded to sound like it was played with live acoustic instruments and human voices , and you’d end up crying.My audio system wasn’t integrated with its current shape in mind. Originally, it had bookshelf speakers as fronts, and sats all around, with 50 W for the fronts and 30 for the rest. Some last minute jockeying for the price and some floorstanders which my integrator was trying to dump let me get an 18K setup for 14!, with the catch being that I’d never be able to run it at full juice (at least for the speakers anyway).
Usually, I run it with the sub on full power and the rest on about quarter to half. even when my friends come over ‘cos the last time I tried it, I blew out a fuse:( Spades of bass is a good thing for handling Jazz and Country, but not trance or heavy Rock. So I decided to tilt the balance in favor of the fronts and turned down the sub to half. And I heard my main speakers distort for the first time .In fact, I saw the clip LED’s turn on!
Most of my friends say they like listening to trance and rock. But I’ve always had problems reconciling to that. Now I know why…DISTORTION!!
Rock especially demands a bit of distortion, and lesser systems and ALL ordinary pc speakers start distorting by the quarter mark. This adds to the sound which I had been missing .I had a hint of that when I took one of my CD’s downstairs to listen it on his Panasonic mini compo...Manson sounded way better at the minicompo pushing 70% power than in mine at the 10% I usually I run it at! I got the same sound out of mine at its three quarter mark, which was, I must add quite loud!
The answer to all this lies in distortion, and its mechanism. Tons of enthusiasts have raved about ‘valve’ sound and how much better it is when compared to transistor sound. Frankly, it’s just a measure of the distortion and more importantly, when and where it kicks in that is important. Valves (triodes, tetrodes, pentodes) etc have higher distortion levels at ordinary levels (2~5% is typical) but the thing is, distortion levels don’t increase much with greater power levels. even then, it is more due to even order harmonics (which are much more pleasant sounding than odd order harmonics).
Transistor Amps meanwhile give a slight distortion at minimum levels which decreases to almost negligible levels at the designed power level after which it rises Quite sharply. An amp which is rated at 100W RMS at .08% THD (total harmonic distortion) will manage 120 with as much as 10% distortion which is mainly due to power supply clipping and device non linearity.
And to compound their woes, most transistor amps are run in class B unlike valves which run in class A which gives better linearity
All said, I love transistor distortion! Who knows, in the future when digital amplification has taken over, there will be old timers like us vouching for how transistor sound is better than ‘Digital’ sound!
posted by kickassso, 10:18 PM
TWEAKER:>
Some of my friends had modded or overclocked or done something to their PC's . I never felt any deficiency in my PC except for a shortake of RAM so had held back from doing stuff. And that mods in my domain of experstise...(sound) was harder to do..But now...>:) I can also claim to have done something... my onboard Realtek ALC650 based solution is the subject of these tweaks... the nvidia utility That is supposed to be used for nforce ' boards apparently has a few hidden options .A few registry hacks later...ta da.............
the advance settings page is nice and the audio firewall is even better giving more control of over the degree of acess each program might have over the audio device...the only problem is that the ALC 650 is just a "CODEC interface" and not a hardware accelerated sound device. so all these remain on s/w to match this...I tried runnig SRS circle surround II decoder and the soundcard utilites. The surround performance was quite adequate but IT did have a bit of distortion at top levels and cpu usage was 20%:( ...software acceleration...[ rolleseyes]..IF you wannna do it ...feel free to ask
posted by kickassso, 7:33 AM
Scope of the Device
NO Discussion would be complete without the scope of the said deviceIn this we usually discuss the future of a project. Frankly we think our project is the future. Advanced recognition techniques and sensors are being developed with better characteristics and lower costs enabling faster cheaper and more accurate detection. A project of this scale would have cost much much more a decade ago. In our case development of powerful microcontrollers as well as reliable detectors makes it better than fast attempts at the same.
A 2D array can provide significantly enhanced control ability, because of the fact that instead of two control directions. In a 2D array we can achieve 8 directions (or more). They can for example be used to select an option for which the control can be applied.
Even among the sensors SHARP offers significantly wider range with modules capable of sensing and transmitting the sensed distance. Instead of just a logic level which is a result of the comparison of the sensed distance with a preset value. An array of such sensors could achieve, in the manner mentioned previously, 3D sensing which can offer a much more powerful interface. Eg motion replicators etc.
The decoder stage ie(uC) can be reprogrammed with more optimized algorithms (if any are developed) leading to more optimized detection.
Similarly the interface with a PC can also yield better results using powerful software.
If mass produced the economies of scale can reduce the cost of this interface allowing it to be economically incorporated into a host of devices allowing for an unprecedented change in the way in which humans interact with the devices by simplifying the man machine link.
Embedding the interface into physical space enables the creation of reactive environments that can automatically respond to user’s gestures.
We have already mentioned a limited number of applications so far. Where as the actual no of possibilities are limitless. The range of application of this interface is limited only by human imagination.
posted by aravind, 9:44 PM
How to design the kinematic Intuitive control interface
Our Approach
We decided to use a linear array of proximity sensors to detect the presence of hand and its position. The so detected information was to be sent to a decoder which would determine the required control information from the input given to it. The control information could be used to interface with a variety of devices in the parallel format.
Three options were initially available to us for non contact detection.
- Ultra sonic proximity detection
- Capacitance based detection
- IR based detection.
- Camera based detection.
Ultra sonic detection was primarily ruled out because of its bulk and its slow response. Capacitance based sensors offered the most discrete sensing but were also ruled out over questions of possible interference between detectors and detection speed. Camera based detection was considered, in which the video feed from a camera would be analyzed using DSP to determine the predominant motion vectors. This would have enabled a wide range but at a very much increased cost and complexity of both the hardware and detection algorithms. Moreover possible false triggering also posed problems to similar models in development now. Thus a hardware based approach employing infra red sensors was chosen. Infra red sensors have the advantage of being invisible and having a fast response time.
This device worked well in preliminary trials, giving consistent outputs for up to two receiver transmitter pairs operated simultaneously. However a larger no of devices coupled with high sensitivity of TSOP 1738 module caused interference between the sensors leading to latching. Remedying this increased the circuit complexity to an unviable level (compromising the goal of cost effectiveness) Hence all costs taken into account a suitable replacement. Was found in later stages of development in the Sharp GP2D15 which offered detection of object based on the angle of the reflected light and thus could be used simultaneously with other devices.
LOGIC
The digital output thus obtained was to be fed to a decoder section consisting of, initially, hardwired digital logic detection based on a bank of comparators shift registers and gates. The output of which control a self stopping four bit up/down counter. But as the detection logic was optimized and made more reliable the part count increased to highly unmanageable level. At this stage a microcontroller was considered as a possible replacement.
Why 16f628?
Of the two types available the 89C51 and the 16Fxxx series the 16F series was chosen due to the simplicity of its hardware and software implementation. 18 pins (two ports) and 35 instructions it’s a much more elegant solution. However there are two mainly used 16F series ICs are 16f84, 628, and 877. The 877 has more ports (4) than required and was not considered. The 16f84 the erstwhile industry standard PIC though still highly popular was not taken and instead 628 was chosen due to the following reasons.
Thus 16f628 was chosen. Initially the detection algorithm used was a direct equivalent implementation of the hardwired logic design. This caused the decoder to have the same problems as the working hardwired prototypes. We realized that since we were working with a microcontroller a much larger range of options were available to us to decode the input as opposed to what was available with hardwired logic. This entire code was rewritten using a new algorithm.
Applications
The scope of such interface is virtually unlimited. It can be used in almost any situation where control inputs have to provided by hand. Example any panel mounted switch or other control. It can be considered as a direct replacement for a rotary potentiometer or up/down digital tapping controls. It can also be adapted to suit a host of other applications. To showcase the wide variety of application we decided to undertake a volume control as the default application. Other applications have been proposed.
Volume Control
It is a digital 16 levels x 2dB digital attenuating control working on a four bit input. Variable attenuation is achieved by selecting the inputs of a potential divider tapped at the required levels. Two multiplexers are used one operating at 8db steps (based on two MSB) and the other 2db steps (based on two LSB). The two multiplexers are buffered in between to prevent mutual loading by the two resistor network and also at the input and output. A high quality and low noise and distortion dual op-amps NE5532 are used. A led display for the volume level is also integrated to give the user a visual indication of the input volume levels. The Samsung KA2281 dual channel five level LED display driver IC is used for that purpose. Control of this is achieved using a parallel interface. There are two sets of inputs and outputs Using RCA connectors and mini stereo connectors. The mini connectors are given priority (if connection is given to both the mini and RCA connectors input from the mini connectors will be chosen).
A five volt DC output is provided for independent power for the interface.
Other Applications
The implementation of the parallel interface allows for the easy connection to a parallel port. Serial port connectivity is also provided using the inbuilt USART of the 16f628. Thus a variety of options are available to interface for the user. Thus support for all standard LEGACY connectors is provided. Support for more connection standards can be added by using the available converters.
At the PC end the four bit output will be available in the registers associated with the ports. This data can be used to control applications running in the PC. This itself provides a much larger scope for e.g. volume control of programs running in the PC as well as using the interface as a scroll tool.
Alternatively the decoding provided by the microcontroller can be bypassed and the four bit input from the sensors fed directly to the PC for more powerful processing using packages like MATLAB.
We can input binary data into this but at the cost of increased physical and mindless effort.
posted by kickassso, 3:27 AM
My First Project
Aaah my first electronic circuit…the fruit of my frustration at the local faculty’s attempts to deny me the joy of the op amp early in my btech. We had to do a paper on voltage regulators. I had studied and gone thru quite a few books to get mine ready. and it was quite exhausting. I had gone the whole hog and did even op amp voltage regulators which were ….oh how I hate the phrase. .”Out of syllabus” the problem of which was compounded by two conflicting diagrams in two textbooks, one by Boylestad and another by Remanan. Anywhere I took the doubt I was given the “no op amps till fourth semester” reply by all lecturers. I decided to take it upon myself to get to the truth myself. After learning of course that 741 op amps were Rs 6 each and not obscenely expensive. And I needed something to step down the 12 turntable motor voltage supply from my old Panasonic hi Fi. Most people would have used an lm317 and gotten it over with .unfortunately my research wasn’t that exhaustive. I decided to build the step down voltage regulator. But being a keen audiophile and having read to no end about noise hum and distortion, decided to back up my bets with the proven ripple rejection of a monolithic regulator. A 7806 was chosen for the task because 6 v was the min voltage a 741 worked at. The reference was…an LED. I understand it was unconventional, but understand me….it was an extremely ‘green’ engineer then who thought that zeners existed only up to 4.5 volt ( I wonder where I got the idea) and that the zeners below that value were not actually in the right breakdown mode.(SURPRISE!! Zeners below 4.5 are the real zeners, those above work on avalanche mode and are more stable) then I had an option to use a potential divider from the 7806 output. compared to that a 2 v from a forward biased led looked far better.( I had thought about using an ordinary diode also…but I had seen a log graph of v/I for all diodes and ordinary diodes didn’t look good compared to an extremely linear performance by led’s. forward biased transistor junctions gave a good performance but in those days I felt that it was a perverse use of a transistor .and thus it was decided. I was going to build it
This circuit, if you’re new to electronics is very good because it constitutes both types of voltage regulators. The op amp one is similar to what the IC 7806 looks from the inside. The design of the 7806 part was fairly straightforward as the datasheet came with an elementary diagram and design suggestions. The op amp design was what it came down to.
THE OP AMP
For those of you who don’t know what an op amp is, it s a circuit block that compares two voltages and gives an output which is proportional to the difference. Typically the constant of proportionality called the gain should be infinite. Most op amps achieve 10^5 and is for all practical purposes assumed to be infinite. How we get to make any use of this gain is by making it (heh heh) eat its own output and thus improve it. How it happens we shall see later. Oh and the process is called feedback. Another thing you will find out about sooner or later in electronics. in this case, the two inputs are the voltage from the LED (2v) and a fraction of the output taken by the potential divider formed by r2 and r3.the op amp gives an output proportional to the difference. Suppose the diode is at 2 v and the output of the potential divider is at slightly higher value (it should also be at 2 v. if it is higher it means that output voltage is higher. and the circuit being made to be a regulator would make its creator…meJ verry sad if it didn’t .but I’m a good creator and the circuit does it…how?
Ill tell you.)The slight increase is amplified by the op amp. But notice that the circuit is wired such that output is proportional to V diode –V divider. This is because the diode is connected to the positive input and the potential divider to the negative input. NOTE: you NEVER and I mean never connect the output of an op amp to its positive input unless you really know what you’re doing (and what you’re doing is an oscillator or a latch of some sort).anyway the small difference gets amplified …but negatively and fed to the output transistor. This transistor is here in what of you know as the common collector configuration. Input is at base and output at emitter leaving the collector to be common.
The difference causes the transistor to decrease current and reduce voltage. See how the output, when fed in the right way causes output to improve. What you just have seen is what is called feedback or more precisely negative feedback at work…TA-DAAAAA!
What you know now is more valuable in understanding an op amp than anything else. I know it helped me make sense of op amps and also a shocking fact that the foreign (Boylestad) text was wrong! Now comes the design part there are only three resistors to be designed here the one in series with the led and the two forming the potential divider.
This is the part where you use your instincts. There are no single correct values. Only a range from which we choose. For example the current limiting resistor for the led. Ideally it would be as low as possible if we want the led to be bright but then our current source is limited and we don’t want to blow up our led! Aim for a few mA. For the potential divider the opposite case is true. We can make the resistor values as high as possible as all we need is a voltage and no current is required. If we had an ideal op amp it would have been the thing we would have done. But it is not because it has an input impedance of only 47 k( ideally should be infinite to prevent loading…of the circuit in this case the potential divider) so here also an a rule of thumb we agree to get resistors in the k ohm range .but the values are up to your discretion, just enough such that the output of the potential divider is 2v at output voltage = to voltage you want. So I am all ready to plug the walkman into the circuit. It works fine…I used an SL100 as the power transistor. You can use any power transistor…you know the bigger ones. I use it on headphones for one night and no troubles result. The next day I connect the walkman output to my Hi Fi and guess what …all sorts of bangs and pops. I’m stumped and desp! Finally a cool head and several checks later it turns out that my walkman is the problem. Its output ground is a few volts ABOVE 0 V so I cant connect both of them together without letting some serious short circuits…it is ort of like connecting the input and output of a bridge rectifier to the same C.R.O because there also the ground points are not the same. Thankfully it turns out that it is just a dc component that was cured but adding an amplifier stage to it. I would have used an op amp there also but since I needed to run it off a car battery during power cuts I used a power amplifier IC TDA 2822 sort of like an op amp but with lesser gain so that you need not add anything to reduce the gain as you would to an opamp. This one gives a fixed gain of about 100 as opposed to 10^5 for an op amp. the capacitors are there to block dc…(RC coupled amplifier remember. only here the r is inside the IC)and the r c at the output is called a zobel network…no need to learn that now just something used at the output of most audio amplifiers to improve High freq stability. WHEW! That’s about it for today. Any doubts?….feel free to comment!
posted by kickassso, 11:59 PM
