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TransistorAmp BJT Transistor Amplifier Circuits Designer Software For the design of transistor amplifiers there is a new software available: TransistorAmp. With TransistorAmp you are able to create your individual transistor amplifier with a few mouse clicks. TransistorAmp is freeware.The tool TransistorAmp has a very easy to use user interface. You start every design with the menu item “New Amplifier”. In the pull-down-menu you choose your desired circuit. You can choose between, common-base-circuitcommon-emitter-circuitcommon-collector-circuit After that you get a dialog, where you have to put in all parameters of your amplifier. For the selection of the transistor type you can click on the button “Select transistor type from list”, and you will see a list of all supported transistor types. TransistorAmp supports some thousand transistor types. Select your desired transistor type there and click on OK. The selected transistor type will then be displayed in the dialog. TransistorAmp software.zip alternatif FileSwap.com : TransistorAmp software.zip download free

This is circuit 13.8V, 40A Switching Power Supply,It is high current power supply switching regulator.And Nice Circuit for power user. This article was originally published (in a slightly modified form) in the QST magazine, December 1998 and January 1999, and in the Radio Amateur's Handbook, 1999. Visit the American Radio Relay League for information on these publications, and a world of ham radio related things! Design decisions There are several different topologies for switchers in common use, and the first decision a designer must take is which of them to consider. Among the factors affecting the decision are the power level, the number of outputs needed, the range of input voltage to be accepted, the desired tradeoff between complexity, quality and cost, and many more. For this power supply I decided to use the half bridge forward converter design. This topology connects the power transformer to a bridge formed by two power transistors and two capacitors. It is reasonably simple, puts relatively low stress on the power transistors, and makes efficient use of the transformer's magnetic capabilities.The second basic decision is which switching frequency to use. The present trend is to use ever higher frequencies. But by doing so it becomes more difficult to filter out the RF noise inevitably generated by the switching. So I decided to stay at a low switching frequency of only 25 kHz for the full cycle, which due to the frequency doubling effect of the rectifiers results in 50 kHz on the output filter. For the main switching elements, bipolar transistors or MOSFETs can be used. Bipolars have lower conduction losses, while MOSFETs switch faster. As in this design I wanted to keep the RF noise at an absolute minimum, very fast switching was not desired, so I used bipolar transistors. But these tend to become too slow if the driving is heavier than necessary. So, if the transistors have to switch at varying current levels, the drive to them must also be varied. This is called proportional driving, and is used in this project. The half bridge converter is best controlled by pulse width modulation. There are several ICs available for this exact purpose. I chose the 3524, which is very simple to use and easy to find. Any 3524 will do the job. It can be an LM3524, SG3524, etc. This basically ends the big decisions. From now on, designing the circuit is a matter of calculating proper values for everything.

New version of the DiSEqC-Tester using ATtiny2313: Schematic diagram: Orijinal görüntüsünü görmek için buraya tıklayın. 580x345 px. Enlarge DiSEqC-Tester_T2313_rev_A - DiSEqC 1.0 (4 ports), 1.1 (8 porst), 1.2 ("west", "east"). After every 4-th/8-th command - large pause (for protocols 1.0 and 1.1). No large pauses in 1.2-protocol mode. The archive contains some diagrams. Number of port-LEDs may be variable, for example 8 or 10, and depends on type of your DiSEqC-Switch. DiSEqC-Tester+ in Proteus (Designators may mismatch): FileSwap.com : DiSEqC-Tester.zip download free Alternatif Link http://www.mediafire.com/?gf2b9m0jzskmull

If you are interested to build TV transmitter for your electronic project this Advanced TV Transmitter With Sound designed by Tetsuo Kogawa could be good idea for you. TV transmitter consists of of the two sections: video transmitter and audio amplifying. Both of them actually is transmitters. The main one generates video carrier while the smaller one generates the exact 4.5 (5.5 in some countries) MHz FM audio carrier. When it is supplied to the main section, the combination generates the audio carrier that is the total of the video frequency plus 4.5 MHz (this is the same in the US but different in other countries: 3.5 in the UK, 5.0 in Italy, 5.5 in Australia and so on: see the channel plans). The Audio section (1)Coil: The most difficult point is the coil. You can use any type of coil as long as it fits the inductance. But the size of coil for 4.5 MHz is quite large if you use usual type of coils. Here I will use Ferrite Troidal core that is made by Amidon Associates. Wind 0.2 ECW (enamel-coated wire) around the "FT-50-43" (Amidon) in 24 turns. (2)Transistor: You can use popular ones such as 2SC2001, 2SC1815, 2SC1907, etc. But you must keep the pins (E, C, B). How to adjust: Connecting the prove of the frequency counter at "#to the audio-in". Then adjust "Trimer cap. (80PF)" as the frequency counter shows exactly 4.5MHz. Sometimes, you have to add some capacitors (depending 100-1000PF) at the "E(mitter)" position of the transistor in order to adjust the frequency.