Rec 137 a• 141_angl_05042000
Transcription
Rec 137 a• 141_angl_05042000
1 Technické informace 050699 Miroslav Gola / OK2UGS Assembling Instructions FM RECEIVER IN BAND 137 - 141 MHZ (superheterodyne with double commingling and PLL) PØIJÍMAÈ FM V PÁSMU 137 - 141 MHZ SUPERHETERODYN S DVOJÍM SMÌOVÁNÍM A PLL http://www.emgola.cz/ emgo@iol.cz 2000 AREAL VUHZ CZ-739 51 DOBRA http://www.emgola.cz/ E-Mail: emgo@iol.cz PØIJÍMAÈ FM V PÁSMU 137 - 141 MHz s displejem LCD 2 FM RECEIVER IN BAND 137 - 141 MHZ (superheterodyne with double commingling and PLL) Assembling Instructions ( the text is enclosed to the set of the component parts and the building blocks ) Update: 31. 01. 2000 INTRODUCTION The following text is intended for upper-intermediate radio-amateurs ( not only according to their age ) and it describes building of an UKV FM receiver for the interesting band of 137-141 MHz, where the images from the Space are transmitted with meteorological satellites (views on the Earth from distance of 850 km or 36,000 km). The receiver can be assembled and set very easily - only with a support of a few measuring instruments: a multimeter is enough, and a simple diode high-frequency probe is optional. For your education, it is recommendable to use a great deal of special measuring instruments and learnig, how to use them at this module. Other details about the assemblage ( users pieces 2000 AREAL VUHZ CZ-739 51 DOBRA of information and update changes ) and about receiving the Space pictures can be found on the following web address: http://www.emgola.cz/jak_zacit_meteo.html . The receiver of signals modulated with frequency ( FM ) is assembled on a base of the Motorola MC3362P integrated circuit in the function of a superheterodyne with double commingling with a front-end high-frequency preamplifier and the low-noise FET BF981 transistor. The balance of the receiver oscillator and, thereby, a constant tuning of the selected frequency, is ensured by http://www.emgola.cz/ E-Mail: emgo@iol.cz 3 Technické informace 050699 Obr. 2. Rozloení meteosatelitù na obìných dráhách okolo Zemì using the frequency exchange (PLL) with the integrated circuit SAA 1057 working at frequencies from 126.3 to 1303 MHz with a tuning step of 10 kHz. The receiver is very useful for receiving signals from meteorological satellites NOAA, METEOR etc. in connection with the Turnstile antenna ( two crossed dipoles ) or with the Quadrifillar Helix antenna. If a frequency converter from 1691 to 137.5 MHz is connected between the FM receiver 137 - 141 MHz and a parabolic antenna, it enables to receive very attractive images from the METEOSAT satellite. In the above mentioned band of 137 MHz, meteorological information in WEFAX format from satellites gravitating on polar orbits in heights approximately 850 kilometres are transmitted. After their conversion, WEFAX signals from the METEOSAT satellite at the geostationary orbit 36,000 km far from the Earth can be received. Other information about WEFAX format and its processing ( decoding ) by means of a personal computer can be found in detail at the Internet address: http://www.emgola.cz/wefax_meteo.html We recommend the introductory literature [1] and other variants listed in the literature [2] to be read up. We tried to remake this assemblage and complete it with a frequency stabilisation by means of PLL and with displaying on a LCD display. However, the assemblage can be easily used for reception in the radio-amateur band 144 - 146 MHz. Details can be found on the Internet address http://www.emgola.cz/RX144_146.html 2000 AREAL VUHZ CZ-739 51 DOBRA and in other information enclosed to the WEFAX receiver kits for frequency band from 137.3 - 141 MHz. RECEIVER TECHNICAL DATA Frequency Range: 137 - 141 MHz Frequency Synthesizer Step: 10.00 MHz Input Sensitivity: 0.6uV ( rms-type ) for 12 dB SINAD Intermediate Frequency: 10.7 MHz and 455 MHz Power: DC 9V ( max. 12 V ) Current Output: 70 mA, according to the loudness level setting Power Connector: 3 mm ( + pole is inside of the jack pin, - pole is on its surface!!!) Automatic Scanning of the Stations in the Band ( SCAN ): Yes Noise Gate ( SQUELCH ): Yes Display: LCD 1 x 16 alpha - numerical symbols Antenna Connector: F type Loud speaker or Headphones: external 8-25 Ohms Base Plate Receiver Printed Circuit Size: 138 x 85 mm Receiver Module Size: 140 x 130 x 45 mm DESCRIPTION OF THE RECEIVER FUNCTION The receiver is designed as a superheterodyne with double commingling, and the MC 3362 ( IC1 ) integrated circuit by Motorola Company is the heart of the whole receiver. The scheme of the FM receiver electric connexion for the frequency range 137 - 141 MHz is shown in the enclosure, figure No. 1 and its goes out from the literature [1,2 ]where this integrated circuit was also used for its excellent properties. Look through the scheme in the enclosure, figure No.1 and you will certainly appreciate the simplicity of the electric connexion achieved by using the integrated circuit MC 3362. Its inside structure [ 4 ] contains all the circuit parts of the receiver with double commingling including variablecapacitance diode for a resonant circuit of the first oscillator. http://www.emgola.cz/ E-Mail: emgo@iol.cz PØIJÍMAÈ FM V PÁSMU 137 - 141 MHz s displejem LCD At the power voltage higher than 2V you will get excellent and simple receiver with high input sensitivity. The signal coming from the antenna is brought through the ANT input to a resonant circuit that consists of the coil L1 and of the capacitor C3. The input amplifier T1 is complemented with a transistor with a low noise number of the BF981 type. The electrode G1 of the transistor T1 is connected to the hot ending of the input tuned circuit L1 and the G2 electrode is connected to a voltage divider that consists of R1 and R2 resistors. Meteosat 7, který pøedává meteo snímky na Zemi ze vzdálenosti 35 900 km The amplified signal is led through the resistor R3 to a triple band-pass filter that consists of resonant circuits L2 C5, L3 C8 and L4 C11. The circuits are freely connected to the capacitors C6, C7 and C9, C10. The transistor T1 is through L2 fed with a voltage of 5 V from the stabilised supply with IC5. From a band pass filter is the signal led through the buffer capacitor C12 to the input (pin 1 ) of the integrated circuit IC1. The structure of the circuit IC1 enables simple and steady receiver construction where only a few outside passive parts are connected - the crystal 10,245 MHz, the filter of the first intermediate frequency 10,7 MHz and the filter of the second intermediate frequency 455 kHz. The tuned circuit of the first oscillator L5 and C33 is connected to pins 21 and 22 of the circuit IC1. In the inside circuit structure there is the double variable capacitance diode connected to these pins as well. If the circuit IC is fed with 5 V voltage, the tuning voltage for the varicap of the first oscillator is in the range from 0.1 to 4.2 V. The tuning voltage is brought through a filter to the pin 23. The oscillator oscillates at a differential frequency ( e.g. 137.5 - 10.7 = 126.8 MHz ). It is pre-set at a frequency value of 10.7 MHz lower than the average value of the received band. Behind the first mixer in IC1, a differential component (fIN -fOSC) of the first intermediate frequency 10.7 MHz is amplified in the inside amplifier of the circuit IC1 and it is brought to a ceramic filter F1. A standard ceramic filter muRata 10.7 MHz for broadcast radio-receivers with the best band width to 180 kHz or less was chosen for its common availability . After filtration through the ceramic filter F1, the differential component is brought to the second amplifier, where it is mixed with a signal of frequency 10.245 MHz coming from the crystal controlled oscillator ( X2 ). A signal of the second intermediate frequency is generated at the frequency of 455 kHz which goes through a ceramic filter F2. A filter with the band-pass of 30 kHz is the most suitable for a narrow bandwidth FM WEFAX. 2000 AREAL VUHZ CZ-739 51 DOBRA 4 The resultant differential component with a frequency of 455 kHz is, after going through the filter F2 and after amplification, brought to a quadrate demodulator that works with L6 and C19. All pass network L6, C19 of the 455 kHz demodulator is connected to the output 12 of the IC1 circuit and it is charged with the resistor R6 with the value of 18 - 56 kiloohms. A linear characteristic of the demodulator with a width of at least 30 kHz is needed for a distortionless WEFAX signal. For the first experiments ( but extemporary only ) a 455 kHz ceramic filter from an intermediate frequency of a common AM radio receiver with a band width of 9 kHz is sufficient. However, received WEFAX signal is very distorted and images nearly illegible. A steady component of the demodulated low-frequency signal from the output 10 ( MetDriv ) of the IC1 circuit is led through R4 to the potentiometer P1 with which a sensitivity sill of the noise gate ( SQUELCH ) can be set. At the output 11 ( Carrier Detect ) of the IC1 there is a control signal for the noise gate switch at the level of 0 V ( when the signal has no noise ) or 5 V ( when it is a signal with noise - connection to setting the values of resistance P1 ). The low-frequency signal path ( MUTE ) is disconnected at the level of the control voltage of 5 V at the output 11 IC1 which is after conversion to T2 led to the output 8 of the circuit IC2 ( the amplifier of the receiver final stage ). The voltage close to the zero level at the output 11 IC1 then releases the lowfrequency signal through the IC2. The T3 transistor commensurate with the pre-set noise gate level by means of the potentiometer P1 generates the logic signal SQ OUT by which a mode of the automatic signal searching in the received band ( SCAN ) is controlled. Steadiness of the tuned frequency is provided by a frequency synthesis ( PLL ) Philips SAA1057 (IC4). It is a one chip synthesiser for tuning radio receivers [ 3 ] in bands of U.H.F., and long waves to short waves. Working frequency value is set to 120 MHz by the manufacturer. Nevertheless, it can be easily exceeded up to the frequency of 160 MHz ( provided circuit selection). In the connexion, figure No. 3 of the Assemblage Instruction Enclosure - the synthesiser SAA1057 - IC4 is able to change tuning with the maximal tuning voltage up to the voltage 4.2 V in the frequency range from 110 MHz to 150 MHz. For the first commingling in the FM137 receiver, a signal with the first intermediate frequency lower of 10.7 MHz is used. For the basic receipt range from 137 MHz to 141 MHz the generator generates frequencies in the range from 126.3 MHz to 130.3 MHz ) from 137.0 - 10.7 = 126.3 MHz up to 141.0 - 10.7 = 130.3 MHz ) with a discrete step of changing the tuning of 10.0 kHz. R14, C25 and C26 are passive parts of the phase detector and C27 serves for filtration of the inside stabilised voltage. C28 and R15 set the time constant of the active low-pass which is a part of a chip. In the majority of the applications, a reference frequency is set by an internal oscillator 4 MHz - which is controlled by an outside attached crystal X1. We have chosen saving connexion with a common crystal for PLL and a microcomputer. The X1crystal is a part of the IC3 microcomputer oscillator. A reference frequency is led through the capacitor C24 and the resistor R11 for the IC4 circuit. A signal from the first oscillator of the IC1 circuit ( lower of 10.7 MHz than the received frequency ) is led to the http://www.emgola.cz/ E-Mail: emgo@iol.cz 5 Technické informace 050699 output 8 ( FFM ) of the IC1 circuit. The tuning voltage ( max. 5.5 V ) is led from the power to the output 7 of the IC4. Control inputs CLB, DLEN, DATA are connected to the port P3 of the IC3 microcomputer. The guiding word and the word for setting the ratio of division is provided by a synthesiser ( IC4 ) through a threewire bus C-BUS from the port P3 of the ATMEL AT89C2051 (IC3) microprocessor. Description of the SAA1057 synthesiser was presented in the literature [2,3,5]. The resultant frequency of the first oscillator of the IC1 circuit can be gently tuned with a capacity trimmer C21. The signal from the oscillator buffer ( pin 20 ) in the IC1 is led to the input pre-divider of the IC4 synthesiser through the C35 and the R18 ( pin 8 ). Here, the frequency can be checked by means of a counter. The available tuning frequency for the inside varicap is at the output 23 of the IC1. The needed power voltage of 5 V for the carrier current ( high-frequency ) circuits of the receiver and 5 V for the synthesiser stabilise the integrated regulator tube IC5 ( 7805 ). Moreover, the power voltage for the sensitive input highfrequency parts of the receiver is separated by means of the TLM2 choke. The antenna pre-amplifier can be fed by means of an coaxial cable if the jumper JP2 is connected through the high-frequency switch with the choke TLM1 and C1. The low frequency pre-amplifier IC2 is directly fed with the voltage of 12 V from the input connector U12 = V. Therefore, it is necessary to use an adapter with stabilisation 220 V AC to 9 - 12 V DC for feeding the receiver. DESCRIPTION OF ASSEMBLAGE THE RECEIVER WITH LCD DISPLAY First of all, make sure you have received all the appropriate components and then divide them into particular groups according to order of assemblage into printed circuit boards. Measure the resistance ( in Ohms ) of the resistors with a multimeter and sort them according to their values. Number code on coloured stripes on the surface of the resistors can be helpful. More details can be found in the Assemblage Instruction Enclosure. Familiarise yourselves with marking the values of all the employed parts, especially ceramic capacitors ( e.g. a label 330 means the capacity value of 33 pF, 100 is the capacity value of 10 pF or 101 means that the capacity value equals 100 pF ). This knowledge makes completing the printed circuit boards ( Printed Wiring Board ) easier. Every such a mistake - inserting a component to a wrong position in printed wiring board - will require much time at energising the module. Therefore there is no point in hurrying up with the preparation and it is useful to pay enough attention to it. Attention: Use a high quality tubular tin solder Sn60 to solder the components on the printed circuit board and if it is possible, use a high quality soldering lamp with a temperature adjustable soldering pin. If you are beginners - practice soldering technique on an old useless piece of printed circuit board. If you work with a soldering lamp, foment the required place first and then apply a tubular with a tin solder. You will prevent from burning a hole into Obr. 4 Schéma zapojení pøijímaèe 2000 AREAL VUHZ CZ-739 51 DOBRA http://www.emgola.cz/ E-Mail: emgo@iol.cz PØIJÍMAÈ FM V PÁSMU 137 - 141 MHz s displejem LCD Antenna 6 Power Frequency 137 - 141 MHz UP - Down Volume Squelch the applied solder ( oxidation ) and making an improper link which can cause unexplainable fails of the proper function or a total failure after a short time of using the assembled module. Such a failure is complicated to find, especially for a radio - amateur without special facilities. The other extreme - fomenting the point of soldering for a short time period, imperfect melting of the solder and making tin hillocpieces around the soldering place endangers proper function of the module being assembled as well. These are cold linpieces that deteriorate the proper function reliability of the module being assembled. Well - soldered component has got only minimum amount of the glossy tin solder around its outlet. Before starting to place the components, scan both the printed circuit boards ( Printed Wiring Board ) and mend the possible bugs. Then fasten four pieces of distant poles to the ports in the bigger board corners (basic printed wiring board) using M3 bolts. Start to place the components according to the figure No. 2 and the list of components in the enclosure. Proceed from the smallest components to the largest . First of all, put and solder the resistors, then other passive components, transistors and integrated circuit bases. There is one exception - U1 (MC3362) integrated circuit must be soldered directly to the board. Others will be inserted into bases, but only during energising the receiver. There are inductances - wound coils inside metal covers - in the receiver. Referring to the scheme - figure No. 1 - you can find the inductance L1 at the input before the transistor T1, L2 - L4 in the bandpass, L5 in the oscillator and L6 in the 2000 AREAL VUHZ CZ-739 51 DOBRA Obr. 5. Osazovací schéma pøijímaèe quadrature demodulator. Wind the coils L1 to L5 with 2.75 turns of the enamel wire CuL 0.215 mm at the framework spindle with a diameter of 5 mm, closely and tightly, a turn by turn. All the turns must be wound the same direction ( e.g. clockwise ). Place the winding to the framework, as close to its base as possible. Solder the wire endings to the two closest metal pins at the bottom part of the framework ( for better orientation - coil wire outputs should be soldered to the pins at the plastic fin side ) and the winding should be protected with bee wax. Insert L1 - L5 coils to larger ( basic ) printed circuit board and put a metal cover over the framework pieces so that the distance between its bottom edge and printed wiring board is approximately 0.5 mm. This fact is important - because it will prevent from an accidental short circuit to the metal cover shealth from some of the printed wiring board inputs for the coils. Some cover designs do not require this precaution, nevertheless, do not rely on it. After checking the right orientation of the outputs in the printed circuit, solder the coils and its metal covers carefully. Finally, screw in the ferrite cores made of N01 ( 150 MHz Pramet Sumperk ) material. Complement L5 coil of the discriminator tuned circuit with a common intermediate frequency circuit 455 kHz. Place the metal cover approximately 0.5 mm above the board and solder it. Some discriminator types have got five outputs - two and three in two opposite lines. Our printed circuit board is not suitable for such a design of the L6 coil, therefore cut the middle ( third ) output with pliers before using it within the board. If the discriminator demodulation coil has got a capacitor in its http://www.emgola.cz/ E-Mail: emgo@iol.cz 7 Technické informace 050699 shealth, do not use the C19 capacitor for the board, then. For the present, do not complement the basic board with the ceramic filters F1 and F2 of the intermediate frequency amplifiers 10.7 MHz and 455 kHz. You will need their places for connecting a measuring instrument sensing head during the energising process. For the receivers with the LCD display - the positions for TL1 and TL2 buttons at the receiver basic board must remain vacant! For this type of the receiver, pre-selection switch DIP4 is used. Solder the 5 V voltage stabiliser IC5 directly to the board, it is not necessary to provide it with a cooler. Finally, complement the board with the L1 over L6 coils and the crystal resonators X1 and X2. The other ( smaller ) printed circuit board is intended for LCD display, two potentiometers P1 and P2, a trimmer P3 and two receiver function control buttons TL1 and TL2. The board does not consist of many parts, which makes complementing the board easy. The positions of the components is shown in figure No. 3 in the Assemblage Instruction Enclosure. First of all, insert and solder the P3 trimmer into the board, but do it from the back, from the side with no service print on it. The resistor R10 is used when the models with LCD display have got illumination. Insert the 16-pin connector bridge from the front to the upper gaps line and solder it from the back. The connector bridge must be orientated endways to the printed wiring board . Insert the connector bridge to the LCD display ports form the opposite side and solder it as well. Make sure to that the display is parallel to printed wiring board. The connector bridge can be supplied with a connector placed in LCD display ports to achieve a taking apart connection between the display and the receiver. This is practical if you intend to use the display for various other applications. Finally, insert the two buttons to the printed wiring board from its front side to the ports at the right and solder them. Connect this structural unit (printed wiring board complemented with according to Figure No. 3 ) with the receiver basic board by means of a connector bridge with eleven pins ( in the angle of 90° ). Insert one side of the bridge to the receiver basic board and the other one to the LCD display carrier board. Before this operation, however, the potentiometers P1 and P2 must be inserted to the prepared printed wiring board ports and only some turns must be put on the spindle attachment nuts. Notice that there is no top-coat of the non-soldering mask at the corners of both the printed wiring board which fay during the assemblage. Join both the printed wiring board together by soldering them at these points. After checking the mutual plumb of both the printed wiring board boards the receiver basic board and the front panel with a display, and after a possible correction, solder the connector bridge at both its ends and the two triplets of the outputs at the P1 and P2 potentiometers. At last, fasten the nuts at the potentiometer spindles. Details of the assembling unit can be found in the Assemblage Instruction Enclosure, in the photograph that exceeds the best description. For assembling the receiver option with LCD display, the microprocessor AT89C2051 will be provided with a programme labelled RX137DIP4X. After energising, the receiver can be built into an appropriate plastic or metal box with ports for the display, two buttons, the potentiometer noise gate ( P1 ) and the volume controller ( P2 ). The antenna connector and the power connector 9 - 12 volts with the central pin connected with (+) positive and external connector shealth connected to ( GND ) will be placed at the back panel. RECEIVER ASSEMBLAGE DESCRIPTION ASSEMBLING THE RECEIVER WITHOUT LCD DISPLAY The option of the receiver with the LCD display can be unneeded luxury for many people, mainly, if they decide to receive the most popular meteosatellites only. For this case, setting of the working frequency with the switch DIP8 which is placed on the printed circuit board is sufficient enough. Other possibility is to count the number of the button presses in the direction UP or DOWN with a step of 10.0 kHz. Therefore, complement the receiver basic board only and keep the display board for a possible future changes. Complement the basic board with the two buttons TL1 and TL2 and then place the potentiometers P1 and P2 to the printed circuit and solder them as well. As the potentiometers are not fixed in the panel, it is recommendable to make the two triplets of their outputs steady by soldering them at the top of the printed circuit board. Put the switch DIP8 to the frequency pre-selection position. If you decide to use the display board as well, proceed in accordance with the installation of the receiver with LCD display ( insert the potentiometers P1 and P2, complement the connector bridge, solder ... ) just the resistance trimmer P3, resistor R10 and LCD display will not be complemented. Obr. 6 Schéma osazení èelního panelu s displejem LCD a alternat. instalovanými potenciometrytlaèítky TL1 a TL2 2000 AREAL VUHZ CZ-739 51 DOBRA http://www.emgola.cz/ E-Mail: emgo@iol.cz PØIJÍMAÈ FM V PÁSMU 137 - 141 MHz s displejem LCD Put the buttons TL1 and TL2 to the display board and leave the holes for them on the basic board empty. The potentiometers P1 and P2 are hence fixed better than just with soldering their outputs to the basic board. The microprocessor AT89C2051 will be provided with a programme labelled RX137DIP8X. LIST OF THE ASSEMBLING COMPONENTS: CAPACITORS 1pF ceramic (SMD 0805) C6,C7,C9,C10 - 4 pieces 3p3 ceramic C2 - 1 piece 5p6 ceramic C12 - 1 piece 6p8 ceramic C3 - 1 piece 10pF ceramic C33 - 1 piece 12pF ceramic C5,C8,C11 - 3 pieces 1,8 - 22pF capacity trimmer (CKT1 8-22pF) C21 - 1 piece 33pF ceramic C22,C23,C24 - 3 pieces 47pF ceramic C14 - 1 piece 47pF cer. C19 (complement only if it is not a part of L6 455kHz) - 1 piece 150pF ceramic C13 - 1 piece 2n2 foil WIMA C25 - 1 piece 4n7 foil WIMA C37 - 1 piece 10nF ceramic C35 - 1 piece 10nF foil WIMA C26, C49 - 2 pieces 47nF ceramic C4,C30,C32,C36,C39 - 5 pieces 47nF foil WIMA C38 - 1 piece 100nF 9 ceramic C1,C15,C16,C17,C18,C34,C43,C44,C47 - 9 pieces 220nF foil WIMA C31 - 1 piece 330nF foil WIMA C28 - 1 piece 2M2/50V radial electrolytic capacitor C20 - 1 piece 10M/50V radial electrolytic capacitor C45 - 1 piece 47M/12V(25V) radial electrolytic capacitor C27,C29 - 2 pieces 100M/10V radial electrolytic capacitor C46 - 1 piece 100M/15 radial electrolytic capacitor C40 - 1 piece 1000M/16V radial electrolytic capacitor C48 - 1 piece 8 BASE DIL20 low for IC3 - 1 piece F-KON FC-017 1 Antenna connector F+M (Put on the receiver basic board and solder) 1 piece Distant piece M3x5 mm 4 pieces Nuts M3 Fe/Cd - 4 pieces Connector SCD-016A 1 power socket 12V-2,5mm ( Put on the receiver basic board and solder ) - 1 piece Connector SCP-2009C 1 socket 12V-2,5mm (Connect to the cable into the adapter - attention: polarity! ) - 1 piece Connector CINCH SCJ-0363 1 GM Electronic (Solder into the board at REP. position ) 1 piece Switch DIP 4x GM Electronic (Solder into the board only if using the LCD type ) - 1 piece Switch DIP 8x 1 GM Electronic (Solder into the board at the DIP position, versions without LCD only ) - 1 piece Button P-B1720 switching GM electronic (Solder into the display board at the position TL1. TL2, in the version with LCD) - 2 pieces Button P-B1720 switching GM electronic (Solder into the basic board at the position TL1. TL, the variant without LCD display) - 2 pieces Instrument button GM electronic, at the spindle with a diameter of 4mm (Put on the P1 a P2 potentiometer spindles) - 2 pieces REZISTORS, TRIMMERS A POTENCIOMETERS 2R2 R20 - 1 piece 47R R3 - 1 piece 180R R14 - 1 piece 820R (adjust the display contrast ) R10 - 1 piece 3k3 (2k7 value can be use as well ) R8, R9, R11 - 3 pieces 4k7 R17,R18 – 2 pieces 10k R5,R7,R16, R19 - 4 pieces 22k R4 - 1 piece 39k R6 (39K - 56K - refer to the text) - 1 piece 47k R12,R13 - 2 pieces 50k/G potentiometer TP160, spindle 4mm P2 - 1 piece 100k/N potentiometer TP160, spindle 4mm P1 - 1 piece 100k R1, R2 - 2 pieces 100k trimmer PIHER PT6VK100 P3 - 1 piece 180k R15 - 1 piece INTEGRATED CIRCUITS MC3362 RX FM 2x MF IC1 – 1 piece LM386 NF amplifier IC2 – 1 piece Microprocessor Atmel 89C2051 with the programme RX137DIP4X IC3 (LCD version only ) – 1 piece Microprocessor Atmel 89C2051 with the programme RX137DIP8X IC3 IC3 (versions with no LCD only ) – 1 piece SAA1057 PLL do 160 MHz IC4 – 1 piece LM7805 Stabiliser +5V IC5 – 1 piece LCD-DV-16100 One line display LCD1 – 1 piece TRANZISTORS A DIODS BF981 2 GATE MOS FET T1 – 1 piece BC238 NPN universal TO92 T2,T3 – 2 pieces RED LED any LED diode D1 – 1 piece 1N4007 rectifying diode 1A D2 – 1 piece TO220 COILS 7MC455kHz TOKO 455kHz/600uH L6 - 1 piece CHOKE 560nH - 1 uH axial design TLM1,TLM2 - 2 pieces Wind L with the inductance of 0.1uH 2,75z. refer to the kit L of the circuit L1,L2,L3,L4,L5 - 5 pieces OTHERS X-TAL 10.245MHz Crystal X2 - 1 piece X-TAL 4.000MHz Crystal X1 - 1 piece F 455 kHz/15kHz 1 ceramic filter F2 - 1 piece 10.7MHz ceramic filter F1 - 1 piece BASE DIL8 low for IC2 - 1 piece BASE DIL18 low for IC4 - 1 piece 2000 AREAL VUHZ CZ-739 51 DOBRA TO92 http://www.emgola.cz/ E-Mail: emgo@iol.cz 9 Technické informace 050699 Breaking pins S1G11W GM Electronic (Solder at the position PANEL and hereby connect the receiver basic board with the display ) - 1 piece Loudspeaker Conrad Electronic (Solder into the basic board at the position REP.) - 1 piece Tubular tin solder 1x200 mm Do not waste the solder - there should be some left - 1 piece Printed circuit - Basic board 144-146 138x88mm - 1 piece Printed circuit - Display board 144-146 138x38mm - 1 piece Technical data concerning the semiconductor devices used in this make can be found in the site http://www.elektronikforum.de/ic-id/ or refer to this link http://www.chipdir.com/chipdir/chipdir.html . DESCRIPTION OF THE RECEIVER SETTING First, pay attention to the power supply. This can be divided into the transformation part outside of the receiver ( a professional adapter transforming the line voltage of 220 V into the safe voltage 9-12 volts ) and into the 5 volts stabiliser at the receiver basic board. For emergency and temporary cases a power supply with only a transformer can be used ( however, always, to keep you well-being, it is advisable to use a reliable professional product having the appropriate certificates - e.g. from HAMA company ), with a rectifier and an electrolytic smoothing capacitor. The central port of the supplying adapter is connected to the voltage of +9 ( +12 ) volts and the external cover is connected to the GND. This can be verified by measuring with a multimeter. The basic board is provided with a connector labelled U12V ( the voltage at the central pin is supposed to be positive, the cover is at the potential GND ) which is connected to the adapter connector. The scatterbrained constructors can be pleased with a safety diode D2 that is put in the power supply to prevent from reversing of polarity of the power supply. However, it is not a heal-all. If you work carefully and properly while complementing, there should occur no problems at the power energising. Check, with a voltmeter, the +5 V voltage at the stabiliser output with the IC5 circuit and +9 V ( +12 V ) at the output 6 of the IC2 circuit. If there is the possibility, watch the stress distribution at the IC5 stabiliser output by means of a oscilloscope probe. No flashes or higher noise should be recognised. The receiver board has been complemented with all the components of the receiver part, including the tuned circuits L1 - L6, nevertheless, there are no MF ceramic filters F1 a F2 yet. Next, put an integrated circuit - the low-frequency amplifier IC2 to the base. Do not complement the circuits around the PLL synthesiser and around the ATMEL microcomputer yet. The energising and setting procedure of the highfrequency ( HF ) receiver parts depends mainly on the constructors technical equipment - HF devices - of the measuring working place. It is important mainly if a fault occurred during complementation. In such a case, the HF probe connected to the multimeter or even to an old AVOMET will not be sufficient. For setting the resonant circuits at the receiver input and the discriminator circuit use a wobbler or a combination of HF generator ( even an improvised one for the considered receiver frequency band in the range of tuning in of the 2000 AREAL VUHZ CZ-739 51 DOBRA testing oscillator 137 - 141 MHz, so called beacon, together with a counter ) and the HF diode probe with a multimeter. Connect the 7IC1 pin through the carrier coupling capacitor with the signal of the frequency 455 kHz, preferably with modulated frequency. Connect the oscilloscope to the pin 13 of the IC1 and tune the maximum amplitude of the demodulated signal through the L6 coil. If there is a possibility to change the FM modulation swing, increase it step by step and watch the changing demodulated voltage. By changing the values of the damping resistor R6 ( lower value of the resistor resistance = extending the linear part of the S curve, the recommended range of the R6 resistor values is 18 - 56 kiloohms ), try to reach at least 25 kHz of the wide linear part of the demodulation characteristics ( S curve ). If using a generator without lift regulation it is necessary to change the input frequency 1 kHz by 1 kHz for both sides from the central frequency and register the output direct voltage at the pin 13 of the integrated circuit IC1 into a diagram. Then, the width of the linear S curve part can be read from the graph. The last possibility is to determine the R6 value experimentally during the auditory tests and by watching the display image quality ( minimal noise, the highest loudness level and mainly acuteness of the image details ). The best value will be probably 18 - 39 kiloohms. Now, solder the F2 ceramic filter ( 455 kHz / 30 kHz ) into the printed wiring board. Next step of the setting will be connecting the generator wobbler output or the analyser output to the receiver antenna input. Connect the wobbler probe input at the pin 19of the IC1 ( ceramic filter F1 has not been connected yet ). The wobbler screen will now be able to display the input part characteristics which is not influenced with the probe capacity. Damp L1 with the 50 ohm resistor and tune the band pass filter with L2, L3 and L4 to the centre of the band pass 139 MHz and set the width of the band pass filtration to the value from 137 to 141 MHz. Optionally, by changing C6, C7 and C9, C10 ( 0.5 - 1 pF ), make the reverb circuit coupling critical or moderately higher. Remove the damp of the L1 and tune it to the centre of the received band, to the frequency value of 139 MHz. If there is no wobbler available, connect an optional generator for 137 - 141 MHz ( e.g. a monotransistor make of Colpitts oscillator together with a counter ) to the antenna input and tune the reverb circuits using the above mentioned way for the minimal noise in the demodulated signal, is sufficient. This can be done after the synthesiser PLL energising ( will be described later ). Now, put the F1 filter and all the synthesiser and microcomputer components on their place. After powering up, the communication should be visible on the attached oscilloscope at the pins 8 ( CLB ), 9 ( DLEN ), and 11 ( DATA ) of the circuit IC3 between the microprocessor and the PLL circuit at TTL levels. The sequence of pulses must be displayed there after the microprocessor sends new data to the synthesiser. Set the range of the PLL loop catching . Measure the tuning voltage at the pin 23 of IC1 with a voltmeter. If everything is all right, the voltage must be steady and it, during tuning over with the ferrite core in the coil L5, must http://www.emgola.cz/ E-Mail: emgo@iol.cz PØIJÍMAÈ FM V PÁSMU 137 - 141 MHz s displejem LCD be in the range of 0.4 V and 4.2 V. At frequency of 141 MHz at the display, set the tuning voltage to the value up to 4 volts by turning the ferrite core in the L6 coil. Then apply wax drops to the core in the framework. Failing this, when the PLL loop does not want to catch, check, using the counter, if the oscillator frequency is not out of the range. If the value of the tuning voltage oscillates around the down stop ( approximately 0.3 V ), the oscillator oscillates too high and vice versa. In this case, changing the capacitor C33 value appropriately will be sufficient to solve the problem. If the tuning frequency is at the top limit at even the lowest coil L5 inductance ( with the ferrite core nearly screwed out), it is recommendable to decrease the capacitor C33 capacity and vice versa. If using the recommended materials in the L5 reverb circuit and the recommended capacitor C33 capacity, no problems occur. However, we uncompromisingly expect your precise work when winding and complementing the circuits being tuned. For the frequency of 141 MHz we selected the PLL voltage value of 4 volts for setting. For other set frequencies in the range 137 - 141 MHz the voltage will always be lower. E.g., for the received frequency of 137.50 MHz - the NOAA 12 satellite ( the receiver oscillator oscillates at 126.80 MHz ), the expected voltage value in the junction R16, C31 can be approximately 2.5 volts. After that, check the actual oscillator frequency by means of the counter. For the frequency of 137.62 MHz at the receiver input, the counter connected to the oscillator will read the frequency of 126.92 MHz. By changing the trimmer C21 capacity adjust the oscillator frequency to the desired value. All this can be done provided a perfect connection between the synthesiser and the master microprocessor IC3. Replace the high-frequency generator at the input of the ANT receiver with the TURNSTILE antenna ( without any pre-amplifier for the long distance reception for the time being ) for the frequency of 137 - 141 MHz and tune the operating frequency of the favourite satellite NOAA12 with the DIP1 switch. When all the switches are in the OFF position, the oscillator frequency is tuned to the value of 126.80 MHz ( the NOAA12 satellite ) by means of the PLL circuit and the received frequency is set to the value of 137.500 MHz. If you turn some of the DI P ( DIP 8 x with eight switches - for the receiver without the display ) to the position ON, set the receiver frequency according to the table, listed in the Assemblage Instruction Enclosure. E.g. - the DIP4 switch has no switched contact ( K0 selection ), the oscillator is set to 126.800 kHz and the frequency being received is 137.500 MHz. Or the contact 1 ( K selection ) of the DIP4 switch is switched, the oscillator is set to 130.300 MHz and the frequency being received is 141.000 MHz. It is possible to increase the frequency, step by step of 10.0 kHz, from the switch frequency setpoint DIP4x, using the button TL1_UP. The same operation can be done with the TL2_DOWN button in the down part of the band being received. After switching on the receiver, the frequency adjusts according to the actual position of the DIP switch. One DIP switch can be in the ON position at the time only. If the situation does not correspond with this, the oscillator frequency is set according to the position of the switch with 2000 AREAL VUHZ CZ-739 51 DOBRA 10 Obr. 7 Anténa Turnstile 137 MHz pro kruh. polarizaci 50 5 50 5 m m m m 5 50 mm 50 λ/4.k 50Ω 5 m m λ/4.k 75Ω (54xk=cm) (54xk=cm) k= koeficient zkrácení pouitého kabelu 75Ω libovolná délka koaxiálního kabelu Obr. 8 zapojení antény Turnstile pro kruh. polarizaci http://www.emgola.cz/ E-Mail: emgo@iol.cz 11 Technické informace 050699 the lowest sequence number and the buttons TL1 and TL2 keep their function. HAVE YOU GOT ONLY MULTIMETER IN YOUR ELECTRONIC LABORATORY? Even in the laboratory equipped just with a common sense, multimeter and probably with a high - frequency probe, completing the receiver assemblage can be done successfully. The main condition is highly precise work during complementing the printed wiring board with the components of the required values and mainly it is necessary to place them on their appropriate position. The multimeter will be used for reading the resistor values and for learning the properties of the used capacitors before putting them on the printed wiring board. Another condition is a reliable function of the oscillator with the L5 and the C33 and flawless communication between the PLL loop and the microprocessor. The oscillator function with L5 has already been checked in accordance with the description in the previous chapter. Now, it is the time to set the input tuned circuits L1 - L4 to the resonance for the lowest noise in the output low frequency signal. Set the pre - selection switch DIP4 or DIP8 at all the positions to OFF, by this, the oscillator tunes to the frequency of 126.8 MHz and the supposed signal at the receiver input shall occur, with the frequency of 137.5 MHz. Connect the Turnstile antenna ( or a makeshift of it - a piece of a wire of the length about 110 cm ) to the receiver input. Wait for the NOAA12 satellite pass and during this pass set the tuned circuits to the best reception. If you do not manage to do it during the pass, you can wait for the next satellite pass or chose other source of the testing signal flying over your place, e.g. NOAA14 satellite ( with the frequency of 137.62 MHz ) or NOAA15 ( 137.50 MHz ). In order not to wait for long hours, there is a programme called TIMESAT1 that is able to calculate the pass time of your desired satellite and its position on the sky instead of you. The TIMESAT1 is a part of the documentation for every EMGO receiver and kit, or you can load it. It is on the Internet site: http:// www.emgola.cz. Audio samples of WEFAX signals in WAV format, received from the NOAA satellites, can be found there as well, for you to know, what kind of sounds you can expect from the loudspeaker of the set receiver. More advanced way of setting the receiver in the terms of not very well equipped laboratory requires certain preparation. First, make a simple monotransistor oscillator for the frequency of 137 - 141 MHz ( if you do not have the scheme for it, we will send it to you with pleasure - emgo@iol.cz ) together with a printed circuit or you can get the information from the Internet address: http://www.emgola.cz/easy_vfg.html. You will not be dependent on some of the satellite pass then. After connecting a piece of a wire to the receiver antenna connector ( a paper clip shaped to a letter L will do ) set the DIP4 or DIP8 switch to the frequency of 137.5 MHz. Then, tune over the testing oscillator ( beacon ) frequency to the frequency, when the noise in the set receiver loudspeaker disappears or its intensity drops considerably. If you use the EMGO EASY VFG beacon, you can initiate the frequency 2000 AREAL VUHZ CZ-739 51 DOBRA modulation to the testing signal. The signals being received can be observed at the pin 13 of the IC1 circuit by means of the oscilloscope, or they can be checked by listening in the loudspeaker. First, set the lowest noise in the low-frequency signal by turning the ferrite core in L6. Set the highest magnitude of the sound. Then try to tune the input circuits L1 - L4, step by step, shortening the standby wire antenna ( or by moving the beacon away ) to the lowest voltage at the pin 10 of the IC1 integrated circuit. Shorten the standby antenna so as the noise is stressed during listening to the beacon in the output low - frequency signal, but the desired signal must not disappear. Further, by turning the ferrite cores of the L1 - L4 coils look for the core position by which the noise in the low-frequency signal drops to the minimal value. A screwdriver ( a tool for tuning ) for this use can be made of a skewer ( of hardwood - beech or bamboo ) or of an appropriate piece of plastic - e.g. a narrow stripe of a printed circuit with a ground edge. This is very important, because a metal screwdriver is absolutely inappropriate. By approaching it, the inductance of the circuit being set will be changed. Attention - the toggle level of the SQUELCH must be set before this operation by means of the P1 potentiometer to MIN ( with the button fully right ) and then, after completing the tuning of L1 - L4 select its switch level by tentative listening to the signal being received. Now, the printed circuit board can be provided with an appropriate plastic or metal box. CONTROLS OF THE RECEIVER WITH LCD DISPLAY The DIP4x switch ( in the receiver type with the LCD display ) has not got 8 positions as it has at the receiver without the LCD display, because it would be necessary to enable 4 pins of the ATMEL microprocessor for LCD display control. The microprocessor programme is programmed so as the operating frequency at the DIP4x switch with four positions is set in less synoptical binary code, shown in the table of the Assemblage Instruction Enclosure. Example: All the switches are in OFF position ( 0000H ) and the receiver oscillator frequency is set to the value of 126.800 MHz and the frequency being received is 137.500 MHz. By using the binary code we get 16 positions of the pre-selection - refer to the table of the Assemblage Instruction Enclosure ( attention - at the DIP4x switch, the numbering goes from one to four from left to right, in the binary code tables is the lowest bit the rightmost as it is shown in the table of the Assemblage Instruction Enclosure ). The pre-selection of the channel being received by means of the DIP4x switch, during reading the data from the display, serves for setting the locating point of the tuning element after connecting the receiver to the power source. After repetitional connecting to the power, the locating frequency is set according to the DIP4x pre-selection. It is recommendable to chose and set the operating frequency of your favourite satellite after getting the initial experience with the reception at the DIP4x switch. From the setpoint frequency bz means of the DIP4x switch, the frequency can be increased by 10 kHz steps ( the button TL1_UP ). The same operation can be done with the TL2_DOWN button towards the down part of the band 137 http://www.emgola.cz/ E-Mail: emgo@iol.cz PØIJÍMAÈ FM V PÁSMU 137 - 141 MHz s displejem LCD - 141 MHz:, with the TL2_DOWN button up to 137.000 ( PLL 126.300 ) and with the button TL1_UP till 141.000 ( PLL 130.300 ). The buttons TL1_UP and TL2_DOWN at the front receiver panel ( the type with the LCD display ) have got double function: By short pressing the selected button, the receiver tunes up of 10.0 kHz (UP ) or down ( DOWN ). Pressing the button for longer time, the tuning becomes quicker and it stops after releasing the key. The last function enables to search the transmitter activity in the band 137 - 141 MHz ( Scanning ). First, push and hold the button for the direction of the desired scanning ( UP - DOWN ) and then shortly press the other key. The actual frequency in the band will be displayed on the display and after interception of the carrier transmitter, the scanning stops for two seconds and a message TUNING will occur at the display. This is the right time for pressing any of the two buttons ( if the you are interested in the signals at the sought frequency ) and the scanning will stop. The threshold value for searching is set by SQUELCH ( noise gate ).Turning the potentiometer leftmost disables SQUELCH ( noise gate ) and scanning stops at ever so little indication of the demodulated signal. At the opposite position, the tuning goes over and over in the range of t 137 - 141 MHz, after single 10 kHz steps. It stops only after indicating a very intensive signal ( mostly, as far as the satellite directly passes your aerial ). Select the appropriate value after having some experience with the reception. NOTE: If you are not satisfied with too low SQUELCH hysteresis, connect the pins 10 and 11 of the IC1 ( MC3362 ) with a resistor ( approximately 5 megaohms ) and connect a ceramic capacitor 100 mF ( SMD preferably ) between the pin 11 and GND, in accordance with the Figure 1. Have a nice reception and we expect your advice, notes and mainly your reception experience in extreme terms at the address: emgo@iol.cz. HOW TO CONNECT LOW-FREQUENCY RECEIVER OUTPUT TO YOUR PERSONAL COMPUTER After signal demodulation by FM receiver, an amplitude modulated tone 2,400 Hz occurs at the low-frequency output. This tone is further processed. Thanks to its reliability, a very old system of the modulation format WEFAX ( Weather Faksimile ) is used up to the present for transmission of the black and white pictures through a standard audiochannel. It uses a ( sub - )carrier frequency of 2,400 Hz which is modulated with an amplitude by a video signal. The maximal modulation ( black ) is not zero, but approximately 5% and white is 87%.This compound audio signal is then modulated by frequency to the main carrier, e.g. 137.5 MHz for the NOAA12 satellite. There are several ways how to process the demodulated low-frequency signal. We are going to describe a simple way, based on conversion the amplitude modulation to the frequency modulation ( refer to the Assemblage Instructions for the Easy Interface communicator, the Internet address:http://www.emgola.cz/ easy interface WEFAX.html. 2000 AREAL VUHZ CZ-739 51 DOBRA 12 Obr. 9 Obrazovka programu JVFAX 7.1 The frequency change from 1,500 to 2,300 Hz corresponds to the maximal brightness change. Such an adapted signal is then led via a simple comparator to the computer serial port and it is further processed by JVFAX 7.1 programme which is available at the Internet address: http://www.jvcomm.de The Easy Interface is described in the individual EMGO publication and it is sold as a kit or as a completely assembled functional product. The results that can be obtained with an uncomplicated and cheap interface are surprisingly good, however, they do not reach the digital quality of the picture conversion. Such results can be reached only with eight-bit analogue to digital converters of more expensive models or by processing the WEFAX signals with the sound card supported by JVComm32 programme which is available for loading the address: http://www.jvcomm.de DECODING WEFAX SIGNALS WITH SUPPORT OF SW JVFAX7. 1a OR JVComm32 Decoding the pictures by means of PC is supported with JVFAX programme, version 7.0 or 7.1a [10] that can be configured to many operation modes. For browsing the received pictures, ZOOM function can be used. This function enables enlarging the image up to the maximal picture resolution in the computer memory. Other details can be found in the JVFAX programme user manual which contains more then fifty text pages and goes into tiniest particulars. The user manuals and JVFAX programme in its upgraded version can be easily obtained from EMGO company. The WEFAX images are transmitted as black-and-white pictures, the JVFAX programme allocates them the appropriate colour scheme. Single images ( bit maps ) are transferable to the following programmes: Microsoft Word, Corel Draw and others. RECEPTION AND DECODING IMAGES V JVFAX PROGRAMME ( interconnecting RX and PC, programme setting and control ) Connect the low-frequency output of the receiver to the Easy Interface input with a single shielded cable, ended with the CINCH connectors. Connect the CANON 9 output http://www.emgola.cz/ E-Mail: emgo@iol.cz 13 Technické informace 050699 connector of the Easy Interface module with the COM1 port or COM2 port of the PC with a cable, you have bought ( a cable for interconnection of the modems - without signal cables crossing ), or you have made of 3 meters of fourstrand ( shielded preferably ) cable. the reception and the decoding can be started. Wait for starting the transmission at your selected frequency and finish the optimal setting of the low-frequency amplitude at the Easy Interface according to the frequency analyser unit of the JVFAX programme. Note: Possible problems with image decoding can occur if you have a slow PC. CONNECTING EASY INTERFACE PATCHCORD - PC COM IMAGE RECEPTION AND ITS DECODING BY MEANS OF JVComm32 PROGRAMME - W95/W98/W-NT ( interconnecting the RX and the PC sound card ) Connecting the PC - Interface patchcord ( DB9M/DB9F ): At the CANON DB9M Interface connector: 3 4 5 6 7 - TXD ( Transmitted Data ) DTR ( Data Terminal Ready ) GND ( GND Signal ) DSR ( Data Seat Ready ) RTS ( Request to Send ) At the PC Canon DB9F connector: 3 4 5 6 7 - TXD DTR GND DSR RTS Connecting the PC - Interface patchcord DB25F ): ( DB9M/ At the CANON DB9M Interface connector: 3 4 5 6 7 - TXD DTR GND DSR RTS At the PC Canon DB25F connector: 2 - TXD 20 - DTR 7 - GND 6 - DSR 4 - RTS After loading the computing storage with JVFAX ( the computer must be set to work in MS-DOS, not in Windows!!! ), set the basic working mode first in the configuration menu ( letter C ). Basic setting of the JVFAX7.1 programme: - interface type - COMPARATOR - number of bits - ( 5-8 ) - base address of the COM1 or COM2 port - appropriate IRQ ( you will get a piece of advice form your experienced friends ) Then select the mode with 240 lines per second (WEFAX) or 120 lines per second ( FAKSMILE ) and the appropriate mode. After saving the configuration data at the hard disk, 2000 AREAL VUHZ CZ-739 51 DOBRA Eberhardt Backeshoff, DK8JV, German author of the JVFAX programme ( for MS - DOS, last upgrade 7.1a ), introduced an excellent programme called JVComm32 for decoding WEFAX and FAKSMILE and other modes to the Internet in 1998. This can be found at the Internet address: http:// www.jvcomm.de/ or e-mail address: feedback@jvcomm.de. The author expects us to use some of the common 16-bit sound cards and a computer 486DX with the RAM memory 16 MB, the operation system Windows 95, Windows 98 or Windows NT 4.0 and a high quality graphic card ( High - or True Colour ) with the resolution of 800 x 600 pixels at least. Of course, you can work with older interface models that communicate with the programme via the PC serial port COM1 or COM2. The JVComm32 programme can work at the background and you can process the received images ( browsing them, making cut-outs, sending them to your friends via Internet etc. ). For multiasking, the author recommends Pentium 90 MHz at least and 32 MB of the RAM computing storage as the necessary minimum. The programme can be loaded from the Internet address: http://www.jvcomm.de/ from the DOWNLOADS option. Connecting the FM 137 - 141 MHz receiver to the sound card input of the personal computer is very easy. Connect the receiver loudspeaker output to the Line input of the sound card. If you want to have the independent loudspeaker output, lead out, from the receiver junction P2, C37, C38, a low-frequency signal through a shielded cable to a separate connector at the receiver back panel and then connect it to the microphone ( or LINE IN ) input of the sound card. You can put an amplifier, similar in the make with the IC2, between the connector at the panel and the receiver output junction, in case that your sound card has got lower sensitivity. It is usually not necessary, mainly if you lead the signals to the microphone port of the card. If you decide to use the JVComm32 programme, you can forget the simple Easy Interface for the COM port. The programme configuration for reception of the signals from NOAA or METEOSAT satellites is very easy: set the NOAA or GEOSTACIONARY mode and the sound card. An extensive help for the programme is greatly pleasant for the users as well. http://www.emgola.cz/ E-Mail: emgo@iol.cz PØIJÍMAÈ FM V PÁSMU 137 - 141 MHz s displejem LCD CONCLUSION EMGO Company has prepared a receiver kit for you. This kit contains a complete assembling documentation, bilateral printed circuits with a non-soldering mask and a service applied colour, a set of integrated circuits ( MC3362, SAA1057, ATM89C2051 with the programme RX137DIP4X or RX137DIP8X, LM386, LM7805 ), ceramic filters 10.7 MHz and 455 kHz/30 kHz, a crystal 10.245 MHz and 4 MHz and a set of passive component parts ( including the software for MS-DOS or Windows 95/98 ). Information and complete price list is available at the address: EMGO, Areál VÚH, 739 51 Dobrá, CZ Via fax +420 /658/ 624 426, Tel. +420 / 658 / 601 471 and mobile phone +420 602 720 424, or via E-mail: emgo@iol.cz Rev: 31012000 / OK2UGS http://www.emgola.cz/Index_angl.htm 14 LITERATURE USED: [1] Günter Borchert DF5FC, Funkamateur 2/1995, pages. 153 156 Der Wetterfrosch - ein 137 MHz Satellitenempfänger, continued in Funkamateur 3/1995, page 274 [2] Ing. Radek Václavík OK2XDX, Pøíjímaè a interfejs WXSAT (pøíjem snímkù z orbitálních meteosatelitù). A-Radio Praktická elektronika, series of the articles in issues 2-6/1997. [3] Marík, V.: Kmitoètová syntéza oscilátorového kmitoètu rozhlasových pøijímaèù, Amatérské Radio B3/1987 [4] Motorola, Linear/Interface ICs Device Data, Vol. II, pages 8-82 [5] Philips Semiconductors, SAA1057 - Radio tuning PLL frequency synthesiser, November 1983. [6] ATMEL, AT89C2051 8.bit Microcontroller with 1 kbyte Flash, katalogue lists August 1994. [7] DF2FQ: VHF Empfanger, CQ DL 1/1994 [8] Josef Daneš a kolektiv: Amatérská radiotechnika a elektrotechnika, 3rd part, Mìøení na pøijímaèích, pages 190 - 254. Nae vojsko Praha 1988. [9] Tùma, P. Displej s LED. AR A4/94 page 18 [10] Kolomazník, P.: Pamì EEPROM 93C46 AR B6/93, page 208. [11] Marík, V.: Kmitoètová syntéza oscilátorového kmitoètu rozhlasových pøijímaèù. AR B3/87, page 88. [12] OK2UGS.: Pøijímaè FM v pásmu 144 - 146 MHz s obvodem Motorola MC3362. Elektroinzert 5/97 page 6. [13] OK2UGS.: Pøijímaè FM v pásmu 144 - 146 MHz s obvodem Motorola MC3362. A_Rádio_Electus99, pages 73-79. [14] OK2XDX.: address: http://207.204.29.183/ok2xdx/DK/ DKEN.html [15] OK2UGS.: address: http://www.emgola.cz [16] Ing. Radek Václavík, OK2XDX.: Praktická elektronika è. 7/ 1999 - popis stavby konvertoru LNC1700 MHz. Obr. 10 Program JV Comm32 v akci 2000 AREAL VUHZ CZ-739 51 DOBRA http://www.emgola.cz/ E-Mail: emgo@iol.cz