_______________________________________________________________________________________________ Section 4 - Diagram Contents: - Cable diagram - MTF0070CR0 RF Amplifier module Cable Diagram - MTF0070CR0 RF Amplifier module Connections Diagram - MTF0070CR0 Amplifier module - Component list - SCH0192AR0 (200W UHF LDMOS Amplifier module) - SCH0223AR1 (Control board and display) - SCH0221AR1 (Amplifier interface) - SCH0265AR0 (Mains distribution board) - SCH0288AR1 (Interface board) - E0012 (SP500-27-DI Switch
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Component list MTF0070CR0 Amplifier module Part Name Code Description Qty 00001 01041D 00221B 03207 SCH0192AR0 SCH0221AR0 SCH0248AR0 SCH0249AR0 SCH0250AR0 SCH0251AR0 SCH0252AR0 PN1091A 02402 02512 01400 01408 DET0726 DET0727 DET0728 DET0729 DET0730 DET0732 DET0734 DET0736 DET0807 DET0810 DET0811 DET0812 DET0819 DET0828 DET0839 08502 08527 03017 PN0998A 0W 1206 SMD RESISTOR 2 1nF 1206 2% SMD CAPACITOR 2 75W 1206 1% SMD RESISTOR 2 HSMS-2802*L31 DIODE 2 200W UHF LDMOS AMPLIFIER MODULE 9 AMPLIFIER INTERFA
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200W UHF LDMOS AMPLIFIER MODULE SCH0192AR0 DESCRIPTION The RF module is an integrated TV linear amplifier designed for UHF band, this module employs push-pull LDMOS technology in order to achieve very good efficiency, high linearity and reliability. LDMOS transistors operate in AB class. It is a wideband amplifier over the full frequency, no adjustment is required for the channel change. The board includes RF section amplifier, bias circuit, protection circuit and matching networks.
- Curve response graphic Middle frequency 660MHz, span 500MHz, 2dB/div., reference to the arrow CALIBRATION PROCEDURE - Technical characteristics Power supply voltage Polarisation current Gain for low signal 32V (± 2%) 1.0 cold for each device (2A total), ± 0.
- Calibration steps STEP 1. Close the input and the output of the module by connecting them to a 50W W dummy load and connect the spectrum analyser through a directive sample, in order to look for self-oscillation of the module, if any (anyway the module has been designed so that it would not self-oscillate even if totally decoupled, without any input or output load). STEP 2.
capacitive trimmers, between the two pair of gates, as shown by the mounting plan. STEP 5. Connect serially a c.c. amperometer to the power supply, with scale starting from more than 5A (i.e. 10A). STEP 6. Power the module and check the MOSFET is not absorbing current; this means that the device is integral and working correctly. STEP 7.
Component layout SCH0192AR0 83
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COMPONENT LIST SCH0192AR0 REF.
REF.
REF. DESCRIPTION ELETTRONIKA CODE B2 B3 B4 L1 L2 L3 L4 H1 H2 NTC1 NTC2 IC1 IC2 DZ1 DZ2 DZ3 DZ4 DL1 DL2 PN964AR3 COAX 2:1 BALUN COAX 4:1 BALUN COAX 4:1 BALUN 4 TURNS SILV. COP. WIRE 1.2mm WOUND ON OD 5mm 4 TURNS SILV. COP. WIRE 1.2mm WOUND ON OD 5mm ½ TURN COIL ½ TURN COIL HYBRID COUPLER 3dB 90° ANAREN HYBRID COUPLER 3dB 90° SAGE NTC 100KW PTH NTC 100KW PTH DG419DY DG419DY 15V SMD ZENER DIODE 15V SMD ZENER DIODE 6.8V SMD ZENER DIODE 6.
CONTROL BOARD AND DISPLAY SCH0223AR1 DESCRIPTION The control board SCH0223AR1 manages the operational logic of the amplifier: switching on and off, power supply and fans, alarms and protections, remote control, human-machine interface. All of that is performed by a modern and powerful 16 bit micro-controller, which is the main part of the board. Figure 1 shows the block diagram.
It can be seen that the micro-controller is the heart of the control system, to which the various peripherals (power supply, serial ports, telemeasure socket, AGC port, RF amplifier module, ROM, clock, display and keys) are interfaced. - Power Supply The board is powered with a continuous +24V voltage applied on the J14 connector. From that the +5V voltage, powering the most of the chips (micro-controller, operational amplifiers, display, etc.) is derived by means of a switching converter (see IC19).
RF AMPLIFICATION The J3 connector interfaces the control board with the RF amplification section. Through this connector the micro-controller acquires the forward and reflected powers, unbalancing (if any), and temperature of the critic amplification area. It also allows to inhibit the transistors in case of reflected power alarm, by means of a totally hardware, thus extremely fast protection. Depending on the apparatus, this connector may also allow to enable or disable the cooling fans of the critic area.
TELEMEASURES The J9 telemeasure connector (10 pins socket) is directly wired on a DB9 female connector placed on the rear panel. There are input and output digital lines (TTL level) and analog output lines on this connector, which are used to monitor and control the amplifier by means of a general-purpose remote control system.
level of the interlock signal becomes high (this line has a pull-up towards the +5V power supply voltage as well) and the interlock protection activates switching off the amplifier. Note that in case the interlock protection is not used, the pin 4 of the DB9 telemeasure connector and the earth pin (pin 5) must be short circuited. Otherwise it is possible to disable the monitoring of the interlock chain from menu (see user manual).
PIN N° ON DB9 PIN N° ON J10 TYPE DIRECTION 1 1 - - 2 3 Digital Output AGC Alarm 0V = Alarm 5V = Normal 3 5 Digital Output AGC Alarm 0V = Alarm 5V = Normal 4 7 - - Not used 5 9 - - Not used 6 2 - - Not used 7 4 - - Nout used 8 6 Analog Output Forward power 9 8 Analog Output Forward power DESCRIPTION Ground Table 4: Description of the AGC connector RS232 The DB9 female connector on the front panel is an external communication RS232 serial port, through which a
FIRMWARE UPDATE The microcontroller is provided with a built-in Flash memory containing the firmware. The firmware can be updated with a later version without removing the apparatus from the rack and/or replacing the chip. To upgrade it, connect a PC to the RS232 socket on the front panel of the apparatus by means of a cable DB9 male - DB9 female (pin-to-pin). Launch on the PC the EKAFlash application, select the serial port in use on the PC, choose the update file by pressing the ...
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COMPONENT LIST SCH0223AR1 Part Name/Number Description Qty. Comps.
Part Name/Number Description Qty. Comps. IND MS85 10uH-S IND T100uH-1.
