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This RF power amplifier is based on the transistor 2SC1970 and 2N4427. The output power is about 1.3W and the input driving power is 30-50mW. It will still get your RF signal quit far and I advice you to use a good 50 ohm resistor as dummy load. To tune this amplifier you can either use a power meter/wattmeter, SWR unit or you can do using a RF field meter. RF Amplifier Assembly Good grounding is very important in a RF system. I use bottom layer as Ground and I connect it with the top with wires to get a good grounding. Make sure you have some cooling at the transistor. In my case I put the 2SC1970 close to the PCB to handle the heat. With good tuning the transistor shouldn't become hot. RF Amplifier Printed Circuit Board You can download a pdf file which is the black PCB. The PCB is mirrored because the printed side side should be faced down the board during UV exposure. To the right you will find a pic showing the assembly of all components on the same board. This is how the real board should look when you are going to solder the components. It is a board made for surface mounted components, so the copper is on the top layer. I am sure you can still use hole mounted components as well. Grey area is copper and each component is draw in different colors all to make it easy to identify for you. The scale of the pdf is 1:1 and the picture at right is magnified with 4 times. Click on the pic to enlarge it. Low-Pass Filter Some of you might want to add a low-pass filter at the output. I have not added any extra low pass filter in my construction because I don't think it is needed. You can easy find several homepages about low pass filter and how to build them.

project of circuit potency lineal RF amplifier with BLY90 for Fm transmitter or vhf transmitter Circuit for lineal amplifier for VHF with power source and printed circuit board, using the transistor Bly90 It is to be used as amplifier of potency of RF in the high strip of of the power source that should be capable to supply a tension of 13 volts with a current of 10 amperes. it demands right care in the assembly of the source. Terrified armored transformer, and three shocks of RF to filter the components of high frequency. XRF1 and XRF2 are 30 you turns of wire 25 AWG in a nucleus of ferrite of 1 cm of diameter and 5 cm length. It can use one of a source at/atx bad, it is easier. XRF3 are 100 you turns of wire 25 AWG in a ferrite nucleus and 1cm of diameter for 5cm of length. Or use an usually found in the exits of sources ATX’s. something around 100µH. The capacitors C1, C2, C3, C4 should be ceramic of 600 V or more and the capacitors of 10nF are for 100v. RX cannot be of wire. Power supply circuit for the rf lineal amplifier Orijinal görüntüsünü görmek için buraya tıklayın. 512x223 px. About the transistor BLY90 The Transistor BLY90 was developed to work in the classes THE, B and C, with 12.5V current of 8A. For applications above 175MHZ. Below we have the diagram circuit of the amplifier using an only transistor BLY90. All capacitors should be ceramic. The resistor of 10Ω for 1 w should not be of wire, the entrance impedance and exit is of 50Ω , soon it should be linked with cable of 50Ω . It should be observed the legal restrictions as the operation of that equipment type. Diagram circuit of the project for the rf lineal amplifier Orijinal görüntüsünü görmek için buraya tıklayın. 522x297 px. Printed circuit board for the lineal amplifier with bly90 Below we have the drawing of the printed circuit board of the transmitter, observe that the components are mounted beside the copper and with the terminals the shortest possible, use heatsink in BLY90. lists of material for assembly of the lineal RF potency amplifier Power Supply RX = 22KΩ 1W C1,C2,C3,C4 = 100nF 600V Ceramic C5,C6,C7,C8, =10NF 100V C9 = 100NF C10 = 4700µF C11 = 2200µF D1,D2,D3,D4 = 1N5401 or equivalent. XRF1,XRF2 = 30 turns of wire 25 AWG in nucleus of ferrite of 1cm diameter for 5 length. Optional, use a shock of RF of a computer source, those of the entrance of the net. XRF3 = 100 turns of wire 25 AWG in a nucleus of ferrite of 1 x 5. T1 = Transformer of 12 Volts for 10 Ámperes with screening. Several = box, plugs, cables, etc. Amplifier of RF Q = BLY90 R = 10Ω 2W C1 =15PF C2,C3,C4,C5 = 100PF C6 = 470NF C7,C10,C11 = 470PF C8 = 47PF C9 = 56PF C12 = 22PF CV1,CV2 = TRIMMER 4 – 40PF CV3,CV4 = TRIMMER 60PF MAX. L1 = 3 turns of wire 24 AWG with diameter of 7mm, nucleus of air. L2 = Shock of RF of 0.22µH. L3 = 15 turns of wire 24 AWG around a resistor of 47Ω x 2W (it doesn’t serve as wire) L4 = 3 turns of wire 24 AWG with diameter of 7 mm, nucleus of air. L5 = 1 turns (sees fig. below for details) L6 = 3 turns of wire 24 AWG with diameter of 7 mm., nucleus of air. L7 = 4 turns of wire 24 AWG with diameter of 7mm, nucleus of air. Several = printed circuit board, antenna, cables, heatsink, box, etc. Detail of L5. That project is just for ends of didactic test, that doesn’t implicate in any responsibility of the idealizator about the non operation or illegality of operation of the equipment.

5 Watt rf power devresi (5-Watt Broadband RF Power Amp schematic) Devrenin üzerine extra olarak çıkış gücünün olup olmadığını gösteren bir led devreside eklenmiştir..

Resimde görüldüğü sekilde gerekli voltajları kontrol ediniz resimdeki transistör ise rf modülatör besleme devresidir ve genelde kısa devre yapmış olabileceği gibi bu tür arızalarda modülatörde bozuk olabilir

RF Alıcı-Verici Devreleri ve Bobin Değeri

DVD Signals RF modulator Circuit

Devremiz yapilip denenmistir. Orijinal Resmi Görebilmek için buraya tıklayınız.

Circuit audio power amplifier using integrated lm4782 overtureTM for three channels of 25W with mute and stand-by LM4782 is audio amplifier of three channels capable to supply 25W of potency for channel. LM4782 uses the system of protection of National Self Peak Instantaneous Temperature (˚Ke) (SPiKeTM). Spike protects the exit of the lm4782 of on tension on load, short of the source for gnd, temperature protection and picks instantaneous of temperature. Each amplifier of the lm4782 has a mute circuit and internal stand-by, that can be controlled by logic it expresses. LM4782 can be configured to be used in bridge or in parallel way without complications, it exists several ways to use integrated him. To know more on spike it seeks for AN-898 in the site national.com . Description of the operation of the circuit of the amplifier with lm4782 The circuit described here it is treated of the application suggested by the national semiconductors for an amplifier of potency of three channels with having integrated lm4782. To determine the heat-sink to be used it sees the datasheet of the lm4782. In the way stand-by the drain of current of the source VCC is less than 30µA for all amplifiers and chain drained of the source VEE is typically of 8mA. Bypassing Capacitors To eliminate possible oscillations or instability in low frequency high frequency either is used a capacitor electrolytic or of tantalum to absorb variations in low frequency and a ceramic capacitor to prevent feedback in discharges frequencies. those components are placed in the power lines. Filter high raisin The combination of it Laughs with ci it creates a filter high raisin. The frequency answer is determined by those two components. The point of -3dB can be found using the equation below: fi=1/(2ÀRiCi) (Hz) If a capacitor of blockade dc be used, there is another filter it passes discharge servant with the combination of Cin and Rin. When great values of Rin are used it can happen oscillations in the exit. To determine the type of the heat-sink and other assembly configurations it sees the datasheet of the lm4782. Source for the circuit That proposed circuit requests a symmetrical source of +-25volts that is capable of ?¤ “teão is necessary that is regulated. Just use a good transformer, rectificators and great capacitors of filter of at least 10000µF. The transformer uses transformer torodal preferably, they exist virtual stores that sell transformers and they dispatch for the whole brazil. Schematic of the circuit of the potent amplifier with lm4782 Orijinal görüntüsünü görmek için buraya tıklayın. 524x566 px. Printed circuit board (couple face) side of the it welds suggested by the national for assembly of the potent amplifier of three channels Circuit board (couple face) printed side of the components suggested by the national for assembly of the amplifier Assembly of the components of the amplifier in the board silkscreen of the board of the amplifier It lists of material for assembly of the amplifier Name value tolerance type /description RIN1,RIN2,RIN3 33kP6; 5% 1/4 watt RB1,RB2,RB3 1kP6; 1% 1/4 watt RF1,RF2,RF3 20kP6; 1% 1/4 watt Ri1,Ri2,Ri3 1kP6; 1% 1/4 watt RSN1,RSN2,RSN3 4.7P6; 5% 2 watt ID 2.7P6; 5% 1/4 watt RV 5.1kP6; 5% 1/4 watt CIN1,CIN2,CIN3 1µF 10% Film metallic polyester CN1,CN2,CN3 15pF 20% Ceramic Ci1,Ci2,Ci3 68µF 20% Ceramic Radial / 35V CSN1,CSN2,CSN3 0.1µF 20% Ceramic CV 0.1µF 20% Ceramic CS1,CS2 0.1µF 20% Ceramic CS3,CS4 10µF 20% Radial Ceramic /50V CS5,CS6 2,200µF 20% Ceramic Radial / 50V S1,S2 Key SPDT (on-on) J1,J2,J3 PCB Montage RCA Jack J5,J7,J9,J11 PCB Banana Jack – Black J4,J6,J8,J10,J12 PCB Banana Jack – Red VZD 5.1V Zener Diode 1W U1 LM4782 TO-220 For more information to do download of the datasheet of the lm4782

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.

Components values: T1 = T2 = T3 = BF199 T4 = 2N4427, BLX65, 2N3866, 2N3553 L1 = rf choke (20 turns, 0.2mm on ferrite core, 0.3mm) L2 = 4 t, 0.7mm, 4mm L3 = 6 t, 0.8mm, 6mm, at first turn from T3 L4 = 10 t, 0.2mm over ferrite core L5 = 7 t, 0.8mm, 6mm L6 = 4 t, 1mm, 8mm, 10mm long This 1 watt fm transmitter has been tested and is working as mentioned in this article. If you use replacement components the performances can vary a lot.

Di dalam Tuner blok FM salah satunya terdapat rangkaian osilator, penguat RF dan juga mixer, kita manfaatkan rangkaian osilatornya untuk dikuatkan sehingga jadilah sebuah pemancar FM yang praktis dan memiliki ketahanan tinggi terhadap frekuensi goncang, artinya meskipun dipancarkan terus menerus tidak ada pergeseran frekuensi yang berarti, masih bisa stabil meskipun tidak dikendalikan dengan PLL. Inilah kelebihan osilator yang terdapat pada tuner blok kalau tidak salah jenis osilatornya colppits, di bawah ini gambar osilatornya. Dengan rancangan yang minimalis dan penggunaan komponen juga kecil seperti Resistor dipilih yang berdaya 1/8 watt sehingga dihasilkan sebuah racangan pemancar yang praktis tetapi berdaya cukup besar, menurut data 2SC2538 bisa keluar maksimum 0,5 Watt. Dalam rangkaian saya batasi catu daya menggunakan 9 volt dc karena sudah tiga tingkat penguatan, dan menjamin 2SC 2538 tetap dingin. Jika digunakan untuk mendorong 2SC1971 maupun 2SC2539 sungguh menghasilkan keluaran daya maksimal. Daftar Komponen C1, C7 = 223 C2,C3 = 20pF C6 = 25pF C4,C5,C8,C9 = 102 C10 = 33pF C11 = 10uF C12 = 100uF R1,R4 = 22k R2,R5 = 10 R3,R7 = 47 R6 = 33 R8 = 1k R9 = 10 Q1,Q2 = FCS9018 Q3 = 2SC2538, 2SC2053 D1 = 1N4148 L1,L2,L3,L4 = 5T IC1 = 7809 Untuk merubah frekuensi kerja tinggal putar tuner blok sesuka kehendak kita. Dengan kestabilan osilator yang dimiliki oleh tuner blok tersebut, wah asyik juga kalau digunakan untuk broadcasting. Akhirnya pun dikuatkan lagi dayanya sampai 60 watt, waktu itu saya gunakan transistor 2SC 2539 dan 2SC 2630. ditambah pula dengan Enkoder maka jadilah pemancar yang stereo. Orijinal görüntüsünü görmek için buraya tıklayın. 776x552 px. Orijinal görüntüsünü görmek için buraya tıklayın. 773x569 px. Orijinal görüntüsünü görmek için buraya tıklayın. 783x583 px. Orijinal görüntüsünü görmek için buraya tıklayın. 600x370 px.

Orijinal görüntüsünü görmek için buraya tıklayın. 944x708 px. wodex 2009Fta Plus - wodex 11100 FTA ,Taplin 2009Fta Plus - Taplin 19100 FTA modellerde skartdan rf ve rca da görüntü alamama veyada osilatör kayar gibi görüntüde kayma ve mat bir görüntü problemi olan arızalarda resimdeki işaretlenmiş olan c 1815 transistörü değiştirmek yeterli olacaktır Kullanılabilecek transistörler: 2SC2328A NPN 2SC639 NPN VEYA belittiğimiz transistörler yoksa yada bulamazsanız NPN 500ma---1A arası bir transistör kullanabilirsiniz. Orijinal görüntüsünü görmek için buraya tıklayın. 885x663 px. resimde değiştirilmiş şekli var arkadaşlar.