NA 501 - 3
Contents
1. 6195 SSA 5 4 1 dozy MS 259 1H E sa dvou lAs 980 552 998 698 A SA 4012191 7145 973 8 12 7163 a Y y vide 1001 2105 gt oyo 25 5050 102 za 2950 6 29 250 07124 zno 109 SEDA 220 Y 1881 ye lt ma 5 1 a 2 yi ber u aa 53 aana haz lt o hr 9 28 y er e 824 Leg asa ar 3900 0 S 48 IHNI Hp rs en AS AL ino 18 ely SA b e P 5 lt 3 ON adp E e on 8 on 8 o on 8 ES vaP2. 501 Positioning of power supply internal terminal board PAGE 17 by the Unit controller 1 output on stand by current and voltage monitoring status prompting and alert A fast 80 semiconductor grade protection fuse is serewed on the board it may be fused by the crowbar protection in case of switching transistor damage If this happens a first attempt to replace the fuse may be accomplished after having verified the integrity of the power transistors Usually something is broken so causing the fuse blow up Reparation of this module in the field 15 very difficult if any component other than fuse or a power transistor failed It is suggested to substitute the module with a new one and send back the damaged unit to the factory for inspection and possible reparation 6 5 TheRFcontroland measure board This small board carries all the circuitry to control and protect the RF amplifier stage Let us consider its various loops Two identical buffers 4 and IC3a insulate and amplify the direct and reflected signal detected on the RF output coupler with different gain The main direct power regulator loop is built around the subsequent IC4d op amp which compares the sensed signal with the preset power level on RTS Adjusting this t
3. 13 4 SERVICE AND MAINTENANCE 14 A u ua a ua asua 14 6 SERVICEMANUALD asus SG 15 6 1 SYSTEMDESCRIPTION 15 6 2 INTERNALDESCRIPTION 16 7 REPAIRAND REPLACEMENT OF DAMAGED MODULES 21 DRAWINGS 501 amplifierfront z top internal view D1067 NA 501 amplifier rear and bottom internal view D1068B 501 general electric diagram ver 220 240Vac E0893 NA 501 wiring diagram E0895 501 power supply 1003 SRFB1K0AL2 control display RF controls amp measures board andcomponent layout 20894 SRFB1K5ALM 48V 40A SMPS regulator module diagram and layout power and ri es 501 500 amplifier assembly electric diagram E0857 SRFB1KOIN 2 port RF input splitter diagram and layout E0858 SRFB 1KOPB 2 port RF output combiner amp LPF diagram and layout E0859 5 500 500W amplifier module diagram and layout 20764 SRFBS500W 500W amplifier module component layout
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5. Tit A 1 D o y o 5 0 912 D z o A gt t k 90 2422 1 A LAE PAGE 26 ELECTRICAL DIAGRAM 220 240Vac CONTROLS MEASURES BOARD NA 5015 AMPLIFIER ar tol 922 ZEAE 400 door sey 819 aval N XOL 4 ve _ 189 94 4 4 ve uy zee LEN 620 SA 7 ino ino ezo z WIVIJOLNOO W m Md y 1 a SA 5 door door 0
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7. PAGE 2 NA 501 500W POWER AMPLIFIER 1 GENERAL DESCRIPTION The NA 501 isa highly integrated broadband solid state Mos FetFM amplifier of 500W rated power fitted in a4 unit 19 rack which do notrequire any specific calibration to operate in the 87 5 108 MHz frequency range Its compact size high efficiency wide mains range acceptance low maintenance requirements and broadband construction make this amplifier ideal in medium power repeaters in unattended posts in N 1 systems and as a reserve Its sturdy modular mechanical and electrical construction guarantees a high and an easy maintenance The modules are easily identifiable and inspectable with few interconnections each with the other through multi pole connectors The nominal RF output power is obtained over the full FM range with a mere 8W drive and is particularly stable against time temperature and frequency variations being ALC regulated witha front panel adjustment The output power may be varied from aminimum level to the nominal level and the frequency varied over the full FM range without retouching the drive power or any other adjustment than the ALC control The output stage has a reverse intermodulation figure which is lower than standard bipolar construction due to the all Mos Fet design and approaches that of tube equipment A simple metering and alarm section completes the amplifier permitting an easy check of the
8. 2 o o Z ollo Y offo offo GY O O 5 zolo o lo zolo zo 7 5 SO O O Tax a 83 O 1 O 00000 O TM O 0 31 i gt E Sees 48 40 SMPS REGULATOR 4 le ZT i ELECTRICAL DIAGRAM POWER SECTION 1 SRFBIK5ALM i PAGE 32 SRFBIKSALM 48 40 SMPS REGULATOR ELECTRICAL DIAGRAM CONTROL SECTION PAGE 33 SRFBIKSALM 48 40 SMPS REGULATOR COMPONENT LAYOUT POWER SECTION SRFBIKSALM 48 40 SMPS REGULATOR COMPONENT LAYOUT CONTROL SECTION r PAGE 34 ELECTRICAL DIAGRAM NA 5015 RF AMPLIFIER ASSEMBLY PAGE 35 HOS 6S803 HOS 94 03 8 aSNaS 8 3SN3S T 170 4005 155 leans HIS Y9L03 A J 170 SOLINOW er A svis lt ASTIZA andzno 10 100 4a IT 355 MOOG MOOSE 355 SRFBIKOIN 2
9. CERAMIC M S 1000PF 50V P 2 54 1 80 M S 1000PF 50V P 2 54 1 C83 CAPACITOR CERAMIC M S 1000PF 50V P 2 54 NPO 1 1 C6 CAPACITOR CERAMIC M S 100PF 50V P 2 54 NPO C16 C17 C27 C30 C37 C46 C48 C49 C50 C60 C61 C62 C69 C72 C74 C78 C63 C79 C10 C13 C35 C41 C68 C38 C47 C53 C54 C66 C75 CR1 CR17 CR3 CR4 CR13 CR15 CR16 CR22 CRS CR12 CR14 CR18 CR19 CR20 CR21 1 2 04 5 CS1 P1 P2 P3 Q1 Q2 CAPACITOR CERAMIC M S CAPACITOR CERAMIC M S CAPACITOR CERAMIC M S CAPACITOR CERAMIC M S CAPACITOR CERAMIC M S CAPACITOR CERAMIC M S CAPACITOR CERAMIC M S CAPACITOR CERAMIC M S CAPACITOR CERAMIC M S CAPACITOR CERAMIC M S CAPACITOR CERAMIC M S CAPACITOR CERAMIC M S CAPACITOR CERAMIC M S CAPACITOR CERAMIC M S CAPACITOR CERAMIC M S CAPACITOR CERAMIC M S CAPACITOR CERAMIC M S CAPACITOR CERAMIC M S CAPACITOR CERAMIC M S CAPACITOR CERAMIC M S CAPACITOR CERAMIC M S CAPACITOR CERAMIC M S CAPACITOR CERAMIC M S CAPACITOR CERAMIC M S CAPACITOR CERAMIC M S CAPACITOR CERAMIC M S CAPACITOR CERAMIC M S CAPACITOR CERAMIC M S CAPACITOR CERAMIC M S CAPACITOR CERAMIC M S DIODE BZX55C16 DIODE BZX55C4V7 DIODE BZX55C4V7 DIODE 7 55 33 DIODE BAV21 DIODE BAV21 DIODE BAV21 DIODE BAV21 DIODE BAV21 DIODE 2 55 18 100PF 50V P 2 54 NPO 100PF 50V P 2 54 NPO 100PF
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11. 501 500W POWER AMPLIFIER USER AND MAINTENANCE MANUAL 9 PWR REL ON 22 ne O O O O G RFL POWER olu Y O NY GG Y NY Y SY XJ Ye PAGE 1 CONTENTS 1 GENERAL DESCRIPTION 3 2 TECHNICAL FEATURES JL AAAS ia awa iio 4 2 1 FRONT PANEL COMMANDS AND SIGNALLING 4 2 2 THE REAR PANEL AND THE CONNECTION S 5 2 3 TECHNICALSPECIFICATIONS 6 24 I OREMOTE CONTROL SPECIFICA TION S 6 3 INSTALLATIONANDUSE 55 566 7 31 FOREWORDTO INSTALLATION 7 222 PLACINGTHEUNIT 8 3 3 WIRING INTO THE MAIN S 9 3 4 ANTENNA CONNECTION A A u Sau usa qa qaa usss 9 25 ULE CONNEC PION 10 36 OTHER RECOMMENDATIONS 10 3 7 OPERATION Sq 12 3 8 POSSIBLEMALFUNCTION S
12. INPUT SPLITTER ELECTRICAL DIAGRAM gt x L Y Y m A me Sey 2 US mas er 160 160 ecte 0 J rect pw FS 7 os gt 29 28 4 08 OF a0 u al Che aCe 165 163 A ac eo cu 1114144 PAGE 36 1 2 OUTPUT COMBINER amp LPF ELECTRICAL DIAGRAM 5 me 5 E Yo Us 1 _ 3891 Dn x XN 8 58 Y wr ES 5 E s Hl E IN 2 IN 1 PAGE 37 SRFB500W 500W AMPLIFIER MODULE ELECTRICAL DIAGRAM L1 NAO 4 C1 L2 TANDA R1 el 11 R15 14 216 12 LI d R3 R5 R19 E Hd E 221 1 y Y T1 NES
13. RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M 220 1 2W 10 220 1 2W 10 220 1 2W 10 330 1 2W 10 330 1 2W 10 1K 1 2W 10 1K 1 2W P 10 470 1 4W P 6 35 470 1 4W P 6 35 470 1 4W P 6 35 11K 1 4W P 6 35 220K 1 4W P 6 35 220K 1 4W P 6 35 220K 1 4W P 6 35 2K2 1 4W P 6 35 2K2 1 4W P 6 35 2K2 1 4W P 6 35 2K2 1 4W P 6 35 2K2 1 4W P 6 35 2K2 1 4W P 6 35 2K2 1 4W P 6 35 2K2 1 4W P 6 35 2K2 1 4W P 6 35 2K2 1 4W P 6 35 2K2 1 4W P 6 35 2K2 1 4W P 6 35 27 1 4W P 6 35 9K1 1 4W P 6 35 100 1W 1 10 100 1W 1 10 1K2 1 4W P 6 35 1K2 1 4W P 6 35 1K2 1 4W P 6 35 1K2 1 4W P 6 35 3K3 1 4W P 6 35 3K3 1 4W P 6 35 2K7 1 4W P 6 35 2K7 1 4W P 6 35 RESISTOR S M 470K 1 4W P 6 35 RESISTOR S M 470K 1 4W P 6 35 RESISTOR S M 470K 1 4W P 6 35 RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR
14. 1 AA o dog Oj o O Yo 5 la D q T 9 o O SS DA N H W o lo 6 O DOO OOo oe O 5 O THe TD flo M 25 NA 501 AMPLIFIER BOTTOM INTERNAL VIEW 2 2 210 IN 9 gt 9 y 2
15. C23 C24 220 he C35 4 va a C37 R14 RF OU 241 WA 7 2 4 rra c39 ee C36 zty _ c21 Y ete 2 022 le 2 C29 C30 C34 RE PAGE 38 SRFB500W 500W AMPLIFIER MODULE COMPONENT LAYOUT x 59 444 LI EN 5 eee PAGE 39 REF 24 25 26 27 C31 15 16 C17 C18 C19 C20 C21 C22 C23 C28 C41 C39 C5 C40 C33 C30 C36 C37 C43 29 C38 C47 D17 D13 D14 D15 D16 04 05 5 IC3 1 12 POLES P2 5 POLES R16 R5 R57 R58 R31 R61 R62 R33 R34 R45 R47 R48 R3 SRFB1K0AL2 RF CONTROLS AND MEASURES BOARD DESCRIPTION Q TY CAPACITOR CERAMIC 100pF 2 100V NPO P5 CAPACITOR CERAMIC 100pF 2 100V NPO P5 CAPACITOR CERAMIC 100pF 2 100V NPO P5 CAPACITOR CERAMIC 100pF 2 100V NPO P5 CAPACITOR CERAMIC 100pF 2 100V NPO P5 CAPACITOR CERAMIC 1nF 5 50V P2 5 CAPACITOR CERAMIC 1nF 5 50V P2 5 CAPACITOR CERAMIC 1nF 5 50V P2 5 TC CAPACITOR CERAMIC 1nF 5 50V P2 5 CAPACITOR CERAMIC 1nF 5 50V P2 5 CAPACITOR CERAMIC 1nF 5 50V P2 5 CAPACITOR CERAMIC 1nF 5 50V P2 5 TC CAPACITOR CERAMIC 1nF 5 50V P2 5 TC CAPACITOR CERAMIC 1nF 5 50V P2 5 CAPACITO
16. RESISTOR CHIP 1206 10K OHM 1 4W 1 RESISTOR CHIP 2512 100 OHM 1W 5 RESISTOR CHIP 2512 100 OHM 1W 5 RESISTOR CHIP 2512 100 OHM 1W 5 RESISTOR CHIP 2512 100 OHM 1W 5 TRIMMER RES CERMET SMD 5x5 20k OHM G4BT TRIMMER RES CERMET SMD 5x5 20k OHM G4BT TRIMMER RES CERMET SMD 5x5 20k OHM G4BT RESISTOR PTC TO92 2 25 C 1 64 52 54 Q TY TAZA A gt dl gt gt SRFB1K5ALM 48V 70A SMPS REGULATOR CONTROL SECTION REF DESCRIPTION C 1 CAPACITOR CERAMIC M S 0 22MF 50V P 5 08 X7R 1 CAPACITOR CERAMIC M S 470 50V P 2 54 NPO 1 C59 CAPACITOR CERAMIC M S 470PF 50V P 2 54 NPO 1 C86 CAPACITOR CERAMIC M S 470PF 50V P 2 54 NPO 1 2 CERAMIC M S 10000PF 50 P 2 54 X7R 1 CERAMIC M S 10000PF 50V 2 54 X7R 1 4 CERAMIC M S 10000 50 2 54 7 1 9 CERAMIC M S 10000 50 P 2 54 X7R 1 15 CERAMIC M S 10000PF 50 P 2 54 X7R 1 C25 CAPACITOR CERAMIC M S 10000PF 50V P 2 54 X7R 1 C26 CAPACITOR CERAMIC M S 10000PF 50V P 2 54 X7R 1 C29 CAPACITOR CERAMIC M S 10000PF 50V P 2 54 X7R 1 C32 CAPACITOR CERAMIC M S 10000PF 50 2 54 X7R 1 C39 CAPACITOR CERAMIC M S 10000PF 50 P 2 54 X7R 1 C40 CAPACITOR CERAMIC M S 10000PF 50 P 2 54 7 1 C42 CAPACITOR CERAMIC M S 10000PF 50V P 2 54 X7R 1 C43 CAPACITOR CERAMIC M S 10000PF 50V P 2 54 X7R 1 C45 CAPACITOR CERAMIC M S 10000PF
17. 1 C24 CAPACITOR CERAMIC 100PF 1KV 5 08 1 C5 CAPACITOR POLY 2 2MF 250V P 22 5 MKT1822 1 C16 CAPACITOR POLY 1MF 250V P 22 5 MKT1822 1 C21 CAPACITOR CER M S 0 22MF 100V P 5 08 X7R1 1 C3 CAPACITOR ELECTROLITIC VERT 1000MF 200V P 10 35x35 1 C4 CAPACITOR ELECTROLITIC VERT 1000MF 200V P 10 35x35 1 C6 CAPACITOR ELECTROLITIC VERT 1000MF 200V P 10 35x35 1 ELECTROLITIC 1000 200 10 35 35 1 C17 CAPACITOR ELECTROLITIC VERT 1000MF 200V P 10 35x35 1 18 ELECTROLITIC 1000MF 200 10 35 35 1 10 ELECTROLITIC VERT 1000MF 63V 7 5 18 30 5 1 C11 CAPACITOR ELECTROLITIC VERT 1000MF 63V P 7 5 18x30 SXE 1 C12 CAPACITOR ELECTROLITIC VERT 1000MF 63V P 7 5 18x30 SXE 1 C13 CAPACITOR ELECTROLITIC VERT 1000MF 63V P 7 5 18x30 SXE 1 C14 CAPACITOR ELECTROLITIC VERT 1000MF 63V P 7 5 18x30 SXE 1 C15 CAPACITOR ELECTROLITIC VERT 1000MF 63V P 7 5 18x30 SXE 1 C22 CAPACITOR ELECTROLITIC VERT 220MF 25V P 5 08 1 C27 CAPACITOR ELECTROLITIC VERT 220MF 25V P 5 08 1 C23 CAPACITOR ELECTROLITIC VERT 47MF 63V P 3 5 LXF 1 C25 CAPACITOR ELECTROLITIC AX 10MF 40 63V P 17 5 1 C26 CAPACITOR ELECTROLITIC AX 10MF 40 63V P 17 5 1 7 1 C8 OMITTED 1 CR1 DIODE ZENER 7 85 18 1 CR2 DIODE ZENER 7 85 18 1 CR15 DIODE ZENER BZX85C18 1 CR16 DIODE ZENER BZX85C18 1 CR3 DIODE MUR115 BYV27 200 1 CR5 DIODE MUR115 BYV27 200 1 CR6 DIODE MUR115 BYV27 200 1 CR
18. 50 2 54 X7R 1 C51 CAPACITOR CERAMIC M S 10000PF 50 P 2 54 X7R 1 C55 CAPACITOR CERAMIC M S 10000PF 50V P 2 54 X7R 1 C56 CAPACITOR CERAMIC M S 10000PF 50 2 54 X7R 1 C57 CAPACITOR CERAMIC M S 10000PF 50 2 54 X7R 1 C71 CAPACITOR CERAMIC M S 10000PF 50 P 2 54 X7R 1 C73 CAPACITOR CERAMIC M S 10000PF 50 P 2 54 X7R 1 C76 CAPACITOR CERAMIC M S 10000PF 50 P 2 54 X7R 1 C77 CAPACITOR CERAMIC M S 10000PF 50 2 54 X7R 1 C81 CAPACITOR CERAMIC M S 10000PF 50 P 2 54 X7R 1 C82 CAPACITOR CERAMIC M S 10000PF 50 P 2 54 X7R 1 C5 CAPACITOR CERAMIC M S 1000PF 50 2 54 NPO 1 C14 CAPACITOR CERAMIC M S 1000PF 50V P 2 54 NPO 1 C20 CAPACITOR CERAMIC M S 1000PF 50V P 2 54 NPO 1 C21 CAPACITOR CERAMIC M S 1000PF 50 2 54 NPO 1 C22 CAPACITOR CERAMIC M S 1000PF 50V P 2 54 NPO 1 C23 CAPACITOR CERAMIC M S 1000PF 50V P 2 54 NPO 1 C24 CAPACITOR CERAMIC M S 1000PF 50V P 2 54 NPO 1 C28 CAPACITOR CERAMIC M S 1000PF 50V P 2 54 NPO 1 C31 CAPACITOR CERAMIC M S 1000PF 50V P 2 54 NPO 1 C33 CAPACITOR CERAMIC M S 1000PF 50V P 2 54 NPO 1 C34 CAPACITOR CERAMIC M S 1000PF 50V P 2 54 NPO 1 C36 CAPACITOR CERAMIC M S 1000PF 50V P 2 54 NPO 1 C44 CAPACITOR CERAMIC M S 1000PF 50 2 54 NPO 1 C52 CAPACITOR CERAMIC M S 1000PF 50V P 2 54 NPO 1 C58 CAPACITOR CERAMIC M S 1000PF 50 2 54 NPO 1 C65 CAPACITOR CERAMIC M S 1000PF 50V P 2 54 NPO 1 C67 CAPACITOR CERAMIC M S 1000PF 50V P 2 54 NPO 1
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20. functioning with few unambiguous readings Power readings and control are externally available on a remote I O port for an external controller A suitable one may be supplied on request to permit full remote control of the Unit from the studio or another service centre The whole assembly is designed in accordance with the CCIR FCC and tighter international norms and conforms to the recent strictC requirements for EMI susceptance and emission This equipment complies in particular to ETSI EN300 384 and EN 300 447 Broadcast and EMI EMC standards EN60065 and EN60215 safety standards and FCC parts 73 amp 74 PAGE 3 2 TECHNICAL FEATURES 21 FRONT PANEL COMMANDS AND SIGNALLING AN IRA 3 2 3B Te The front control panel carries the power on switch the control meter some alarm warning led s and a monitor connector On the bottom side a gridding on the panel permits the output of the ventilation air At the monitor output BNC type a sample of the output power 15 available which 15 attenuated 54 dB typically 6 2 500W output Evenifthis outputis fairly flat vs frequency itis not suggested to use this for accurate harmonica analysis The switchable meter permits the reading of the most important operating parameters i e the forward andreflected power 500W f s and the regulated and unregula
21. power supply comprises a mains transformer whose output is rectified and filtered and a highly efficient Switch Mode Power Supply regulator The control section is built on one small board It performs RF AGC and protection control providing metering and an interface to the external I O port Both direct and reflected power are displayed and provided as proportional analog signal at the Remote I O port Through this portis possible as well to command the RF output power overcoming the internal front panel regulation 6 2 INTERNAL DESCRIPTION POWER SUPPLY amp CONTROL NA501 Block diagram PAGE 15 The NA 501 amplifier comprises 6 internal different modules boards plus some spare components as can be seen in the drawing of the inner contents and in the General wiring diagram both comprised in this manual The power supply transformer rectifier and capacitor The Switch Mode Power Supply regulator The control and measure board The input power splitter The 500W RF power amplifier module The output RF combiner Low Pass Filter and coupler For the detailed description of each module on the following pages always refer to the corresponding electrical diagram in the relevant section of the manual THIS SECTION IS ONLY AIMED GENERAL KNOWLEDGE OF THE UNIT AND FOR SERVICE PURPOSE BY SKILLED PERSONNEL AS EXPLAINED IN THE PREVIOUS SECTIONS INTERNAL ADJUSTMENTS ARE NOT REQUI
22. 13 DIODE MUR115 BYV27 200 1 CR14 DIODE MUR115 BYV27 200 5 CR4 DIODE ZENER BZX55C20 1 CR7 DIODE BYV10 40 1N5819 1 CR8 DIODE BYV10 40 1N5819 1 CR9 DIODE BYV10 40 1N5819 1 CR10 DIODE BYV10 40 1N5819 1 CR11 DIODE BYV10 40 1N5819 1 CR12 DIODE BYV10 40 1N5819 6 CR17 DIODE BYV27 200 1 CR18 DIODE BYV27 200 1 CR19 DIODE BYV27 200 1 CR20 DIODE BYV255 V200 1 DT1 HEATSINK 1 E1 TEFZER WIRE D2 5mm 13cm E2 SHEATHED WIRE JUMPER 1 E3 OUTPUT BAR 1 E4 OUTPUT BAR 1 1 E5 BUS BAR PART C W 0089 E7 E8 E9 E10 F1 FL1 L1 L2 CS1 P1 P2 PTC1 Q1 Q2 Q3 Q4 Q5 Q6 Q7 R1 R2 R4 R24 R5 R6 R7 R26 R27 R28 R8 R9 R10 R11 R12 R13 R14 R15 R16 R17 R18 R19 R20 R21 R22 R23 R25 R 29 R30 R31 R32 R3 SCR1 SH1 SH2 SH3 BUS BAR PART D W 0089 BUS BAR PART E W 0089 BUS BAR PART F W 0089 BUS BAR PART G W 0089 BUS BAR PART H W 0089 FUSE SUPER FAST L350 80 80LET FILTER INDUCTOR INDUCTOR 22uH D46 INDUCTOR 22uH D46 PRINTED CIRCUIT STRAIGHT CONNECTOR 16P 2 54 L P STRAIGHT CONNECTOR 9P 2 54 L P PTH9M04 BD 471TS2F333 MOSFET IRFP250 MOSFET IRFP250 MOSFET IRFP250 MOSFET IRFP250 MOSFET IRFP250 MOSFET IRFP250 MOSFET IRF720 RESISTOR MET OXIDE 22 3W 5 p 20 RESISTOR MET OXIDE 22 3W 5 p 20 RESISTOR MET OXIDE 10 3W 5 p 20 RESISTOR MET OXIDE 10 3W 5 p 20 RESISTOR S M 1K 1 2W RESISTOR MET OXIDE 4 7 2W 5 p 15 RESISTOR S M 4 7 1 2W RESISTOR S M 4K7 1 2W RESISTOR S M 4 7 1 2W RESI
23. 2 RESISTOR KDI 100 Ohm 20W RESISTOR SMD 1206 22 Ohm 1 4 W RESISTOR SMD 1206 22 Ohm 1 4 W RESISTOR SMD 1206 22 Ohm 1 4 W RESISTOR SMD 1206 22 Ohm 1 4 W RESISTOR RF 200 Ohm 20W 5 RESISTOR RF 200 Ohm 20W 5 RESISTOR RF 200 Ohm 20W 5 RESISTOR RF 200 Ohm 20W 5 RESISTOR METAL OXIDE 10 Ohm 2W RESISTOR METAL OXIDE 10 Ohm 2W RESISTOR 0 01 Ohm 5W 5 RESISTOR 0 01 Ohm 5W 5 RESISTOR KDI 100 Ohm 250W RESISTIVE TRIMMER 20T VERT 5 kOhm 3 8 RESISTIVE TRIMMER 20T VERT 5 kOhm 3 8 RESISTOR METAL OXIDE 1 Ohm 2W 5 RESISTOR METAL OXIDE 1 Ohm 2W 5 RESISTOR SMD 1206 51 Ohm 1 4W RESISTOR SMD 1206 51 Ohm 1 4W RESISTOR SMD 1206 51 Ohm 1 4W RESISTOR SMD 1206 51 Ohm 1 4W MOSFET BLF278 300W MOSFET BLF278 300W VHF INPUT TRANSFORMER VHF INPUT TRANSFORMER Se dd dd SIEL SIEL SIEL SIEL TR3 TR4 21 21 VHF OUTPUT TRANSFORMER VHF OUTPUT TRANSFORMER BRASS M4 TC STUD 400W RF AMPLIFIER PCB SIEL
24. 35 mm W x Hx L See drawings Weight approx 66Lbs 30 kg 24 I O REMOTE CONTROL SPECIFICATIONS A remote I O DB25 female connector located the rear panel makes available 3 analog lines to permit remote control and surveillance of the equipment as detailed Pin 1 3 21 9 10 13 The remote 1 signal and control DB25 female connector on the rear panel Line Range use ground common Reflected Power 0 5 vs 0 550Wout Zo 10kQ 4 V typ E 500W Forward Power 0 5 vs 0 550Wout Zo 10kQ 4 V typ E 500W Power control External RF output control 0 5 to full scale low impedance PAGE 6 3 INSTALLATION AND USE 3 1 FOREWORD TO INSTALLATION Although in mostcases no special instruments are required have skilled personnel install the Unit To make best use of the Units capabilities and prevent damage to the unit comply with the recommendations throughoutthis manual When in doubt orifany technical problems should arise during the installation procedure Nicom strongly recommend the Unit not to be tampered with in any way by unskilled personnel and will be glad to supply qualified after sale service Asarule the user should not have access to the inside of the Unit for normal installation and use Tampering with the factory settings makes the warranty void and mightalso affect Unit performance causing costly damage w WARNING NO ADJUSTMENT OR INTERNAL PRESETTING IS REQUIRED FOR NORMA
25. 4 25 26 27 28 29 C30 C31 C32 C35 C36 C37 C38 39 C40 C41 C42 C43 D1 D2 L1 L2 L3 L4 L5 L6 R1 R2 R3 R4 R5 R7 R8 R9 10 11 R12 R13 R14 R15 R16 R17 R18 R19 R20 R2 R22 T1 T2 1 2 1 100 CAPACITOR SMD 1nF 100 CAPACITOR SMD 1nF 100V COG SMD 1nF 100 PORCELAIN 470pF 10 200 17 PORCELAIN 470pF 10 200 17 PORCELAIN 470pF 10 200 17 PORCELAIN 470pF 10 200 17 PORCELAIN 470pF 10 200 17 PORCELAIN 470pF 10 200 17 PORCELAIN 470pF 10 200 17 PORCELAIN 470pF 10 200 17 PORCELAIN 47pF 5 500 17 PORCELAIN 47pF 5 500 17 PORCELAIN 15pF 5 500 17 PORCELAIN 15pF 5 500 17 PORCELAIN 10pF 5 500 17 PORCELAIN 10pF 5 500 17 2 18 CAPACITOR ELETTR 100uF 63V CAPACITOR ELETTR RD 100uF 63V CAPACITOR SMD 1 100 SMD 1nF 100 DIODE 1N4148 DIODE 1N4148 INDUCTOR 4 SPIRE d6 FILO d0 8 INDUCTOR 4 SPIRE 96 FILO 90 8 INDUCTOR 3 SPIRE SU R2W FILO 41 INDUCTOR 3 SPIRE SU R2W FILO d1 INDUCTOR 3 5 SPIRE d10 5 FILO d2 INDUCTOR 3 5 SPIRE d10 5 FILO d
26. 5 22 1 4W 6 35 22 1 4W 6 35 220 1 4W 6 35 22 1 4W 6 35 22 1 4W 6 35 10 1 4W 6 35 10 1 4W 6 35 10 1 4W 6 35 100K 1 4W 6 35 100K 1 4W P 6 35 100K 1 4W P 6 35 100K 1 4W P 6 35 100K 1 4W P 6 35 7 5 1 4W 6 35 27K 1 4W P 6 35 27K 1 4W P 6 35 1K5 1 4W P 6 35 510 1 4W P 6 35 8K2 1 4W P 6 35 270K 1 4W 7 5 82K 1 4W P 6 35 91 1 4W P 6 35 180 1 4W P 6 35 47K 1 4W P 6 35 2 1 4W 6 35 68K 1 4W P 6 35 1 1 4W P 6 35 15K 1 4W P 6 35 6K2 1 4W P 6 35 330 1 4W P 6 35 150 1 4W P 6 35 3K3 1 4W 0 25 25 P 6 35 15K 1 4W 0 25 25PPM P 6 35 15K 1 4W 0 25 25PPM P 6 35 SPACER FOR TO 5 SPACER FOR TO 18 TRIMMER 10K CERMET 10T 64Y TRIMMER 50R CERMET 10 64Y 100R 10 64Y 20 1 3362 UC3844 1 C LP339N HCPL 3120 HCPL 3120 LM336BZ5 0 1 LM2902N 1 UC3846N Se 09 1 SRFB1K5ALM 48 70 SMPS REGULATOR POWER SECTION REF DESCRIPTION Q ty C1 CAPACITOR CERAMIC 2 2NF 1 5 08 1 C20 CAPACITOR CERAMIC 2 2NF 1 5 08 1 C2 CAPACITOR CERAMIC 100PF 1KV 5 08 1 C19 CAPACITOR CERAMIC 100 1KV 5 08
27. 50V P 2 54 NPO 100PF 50V P 2 54 NPO 100PF 50V P 2 54 NPO 100PF 50V P 2 54 NPO 100PF 50V P 2 54 NPO 100PF 50V P 2 54 NPO 100PF 50V P 2 54 NPO 100PF 50V P 2 54 NPO 100PF 50V P 2 54 NPO 100PF 50V P 2 54 NPO 100PF 50V P 2 54 NPO 100PF 50V P 2 54 NPO 100PF 50V P 2 54 NPO 100PF 50V P 2 54 NPO 2200PF 50V P 2 54 NPO 2200PF 50V P 2 54 NPO 2200PF 50V P 2 54 NPO 1MF 50V P 5 08 Z5U 1MF 50V P 5 08 Z5U 1MF 50V P 5 08 Z5U 1MF 50V P 5 08 Z5U 1MF 50V P 5 08 Z5U 1MF 50V 5 08 7 1MF 50V P 5 08 X7R 1MF 50V 5 08 7 1MF 50V 5 08 7 1MF 50V P 5 08 X7R 1MF 50V 5 08 7 DIODE SCHOTTKY BAT43 BAT48 DIODE SCHOTTKY BAT43 BAT48 DIODE SCHOTTKY BAT43 BAT48 DIODE SCHOTTKY BAT43 BAT48 DIODE SCHOTTKY BAT43 BAT48 DIODE 2 55 15 1 610A 3 1 610 3 1 610A 3 1 610A 3 1 610A 3 PRINTED CIRCUIT CONNECTOR STRAIGHT 16 2 54 L P CONNECTOR STRAIGHT 9P 2 54 L P CONNECTOR FLAT 2x7WAYS STRAIGHT 2 54 L P BC 327 BC 337 Ck ee AA ea Gea ad ee a EEE eR A E E US es he ea E a E ea Sa Sas et ek Sah Q3 Q4 R1 R2 R3 R4 R5 R7 R8 R12 R34 R9 R10 R90 R91 R11 R23 R25 R26 R27 R32 R52 R55 R62 R64 R77 R100 R13 R14 R15 R66 R17 R18 19 R21 R20 R99 R22 R40 R24 R48 R81 R28 R29 R49 R56 R57 R70 R71 R72 R 92 R 93 R 30 R31 R33 R37 BC 337 MOSFET IRDFD9120
28. CAPACITOR CHIP CERAM 1206 220pF 5 100V NPO C6 CAPACITOR CHIP CERAM 1206 220pF 5 100V NPO CAPACITOR CHIP 1206 220 5 100 9 CAPACITOR CHIP CERAM 1206 220 5 100 D1 DIODE 545 SOT23 DUAL SCHOTTKY 2A 30 D2 DIODE BAT54S SOT23 DUAL SCHOTTKY 2A 30 L1 RF LINE L2 INDUCTOR TOROIDAL FERRITE F2 D16x8sp10 R5 RESISTOR CHIP 1206 18 OHM 1 4W 1 R6 RESISTOR CHIP 1206 120 OHM 1 4W 1 R3 RESISTOR CHIP 1206 150 OHM 1 4W 1 R7 RESISTOR CHIP 1206 150 OHM 1 4W 1 R14 RESISTOR CHIP 1206 270 OHM 1 4W 1 R4 RESISTOR CHIP 1206 330 OHM 1 4W 1 R12 RESISTOR CHIP 1206 1 0K OHM 1 4W 1 R13 RESISTOR CHIP 1206 1 0K OHM 1 4W 1 R10 RESISTOR FLANGED 250W 50 OHM R11 RESISTOR FLANGED 250W 50 OHM e C1 CAPACITOR SMD 33pF 100V COG 1 C2 CAPACITOR SMD 10pF 100V COG 1 22 100 1 4 SMD 22pF 100 COG 1 C5 CAPACITOR SMD 100pF 200V COG 1 C6 CAPACITOR SMD 100pF 200V COG 1 C7 CAPACITOR SMD 100pF 200V COG 1 100 200 COG 1 9 47 100 1 C10 CAPACITOR CER 47pF 100V 1 C11 CAPACITOR SMD 1nF 100V COG 1 C12 CAPACITOR SMD 1nF 100V COG 1 C13 CAPACITOR SMD 1nF 100V COG 1 C14 CAPACITOR SMD 1nF 100V COG 1 C16 CAPACITOR CERAMIC 470pF 100V 1 C16 CAPACITOR CERAMIC 470pF 100V 1 C17 CAPACITOR CERAMIC 470pF 100V 1 1 C18 CAPACITOR CERAMIC 470pF 100V 19 20 21 22 23 2
29. K OHM 1 2W 1 R29 RESISTOR RS2F1332 3 32 OHM 1 2W 1 R30 RESISTOR RS2F1332 3 32 OHM 1 2W 1 R32 RESISTOR RS2F1332 3 32 OHM 1 2W 1 R38 RESISTOR RS2F1332 3 32 OHM 1 2W 1 R23 RESISTOR RS2F1475 4 75K OHM 1 2W 1 24 RESISTOR RS2F 1475 4 75 OHM 1 2W 1 R46 RESISTOR RS2F 1475 4 75K OHM 1 2W 1 R56 RESISTOR RS2F 1475 4 75 OHM 1 2W 1 R54 RESISTOR RS2F1619 6 19K OHM 1 2W 1 R25 RESISTOR RS2F2100 10 0K OHM 1 2W 1 R26 RESISTOR RS2F2100 10 0K OHM 1 2W 1 R37 RESISTOR RS2F2100 10 0 OHM 1 2W 1 R43 RESISTOR RS2F2100 10 0 OHM 1 2W 1 R49 RESISTOR RS2F2100 10 0 OHM 1 2W 1 R50 RESISTOR RS2F2100 10 0K OHM 1 2W 1 R51 RESISTOR RS2F2100 10 0K OHM 1 2W 1 R59 RESISTOR RS2F2100 10 0K OHM 1 2W 1 R60 RESISTOR RS2F2100 10 0K OHM 1 2W 1 R22 RESISTOR RS2F2110 11 0K OHM 1 2W 1 R2 RESISTOR RS2F2140 14 0K OHM 1 2W 1 R35 RESISTOR RS2F2221 22 1K OHM 1 2W 1 R39 RESISTOR RS2F2221 22 1K OHM 1 2W 1 R28 RESISTOR RS2F2332 33 2K OHM 1 2W 1 R36 RESISTOR RS2F2475 47 5K OHM 1 2W 1 R40 RESISTOR RS2F3100 100K OHM 1 2W 1 R55 RESISTOR RS2F3110 110K OHM 1 2W 1 R27 RESISTOR RS2F3221 221K OHM 1 2W 1 R53 RESISTOR RS2F3475 475K OHM 1 2W 1 RT1 TRIMMER HORIZ CERAM RES Q10 110 1K OHM RT3 TRIMMER HORIZ CERAM RES Q10 210 10K OHM RT4 TRIMMER HORIZ CERAM RES Q10 210 10K OHM 5 HORIZ RES 010 310 100K TR4 TRANSISTOR 2N 1711 TOS 60V NPN TR5 TRANSISTOR BC556B TO92 65V 1A PNP GEN
30. L OPERATIONS THE UNIT SHALL BE PROPERLY GROUNDED AND BE OPERATED WITH ALL THE COVERS CLOSED TO PREVENT ELECTRICAL HAZARDS IN OPERATION AND FULLY COMPLY WITH CE EMI AND SAFETY REQUIREMENTS NEVER TOUCH THE INSIDE OF THE UNIT WITHOUT FIRST DISCONNECTING IT FROM THE MAINS DANGEROUS DC AND RADIO FREQUENCY VOLTAGES ARE PRESENT INSIDE AND BECOME ACCESSIBLE WHEN THE COVERS ARE REMOVED MAINS VOLTAGE MAY KILL PAGE 7 3 2 PLACINGTHE UNIT Install Unitin adry sheltered butwell ventilatedroomaway from dust moisture insects and vermin mice Place Unitas close as possible to antenna to prevent excessive power loss in the cables If this is not feasible use antenna cables of suitable cross section Room size shall be such that the Unit can be placed in an upright position and that technical personnel caneasily carry outroutine or extraordinary maintenance The minimum recommended size 15 2 5m x 2m and 2 2m high when there is no other broadcasting or support equipmentnearby The room must be ventilated to ensure that the inside temperature never exceeds 35 C Even if 45 Cis the max allowed temperature itis anyway suggested not to approach to this limit This condition cannot generally be met when the exhaust cooling air is not pushed outside and 15 fed back into the room This is even truer if more than one Unit is installed in the same location An efficient ventilation system is thus required in theroom Airexchange inthe
31. P for TR4 TRANSISTOR SPACER TO5 4mm NYLON for IC5 SOCKET DIL08 LOW PROFILE I 7 62 for IC3 IC4 SOCKET DIL14 LOW PROFILE I 7 62 for IC3 1 4 SOCKET DIL14 LOW PROFILE I 7 62 ALA Ad R21 R22 R23 R24 RT1 RT2 RT3 RVT1 SRFB1KOIN 2 PORT INPUT SPLITTER DESCRIPTION RFB1001 INPUT SPLITTER BOARD CAPACITOR CHIP CERAM CAPACITOR CHIP CERAM CAPACITOR CHIP CERAM CAPACITOR CHIP CERAM CAPACITOR CHIP CERAM CAPACITOR CHIP CERAM CAPACITOR CHIP CERAM CAPACITOR CHIP CERAM CAPACITOR CHIP CERAM CAPACITOR CHIP CERAM 1206 6 8pF 5 100V NPO 1206 33pF 5 100V NPO 1206 100pF 5 100V NPO 1206 100pF 5 100V NPO 1206 100pF 5 100V NPO 1206 100pF 5 100V NPO 1206 100pF 5 100V NPO 1206 1 0nF 10 100V NPO 1206 1 0nF 10 100V NPO 1206 100 10 50V X7R DIODE BAT54S SOT23 DUAL SCHOTTKY 2A 30 INDUCTOR CHIP 1210 1 0UH LO Q INDUCTOR CHIP 1210 1 0UH LO Q INDUCTOR CHIP 1210 1 0UH LO Q INDUCTOR CHIP 1210 1 0UH LO Q INDUCTOR CHIP 1210 1 0UH LO Q MALE CONNECTOR C S FLAT CABLE 10p RESISTOR CHIP 1206 56 OHM 1 4W 1 RESISTOR CHIP 1206 120 OHM 1 4W 1 RESISTOR CHIP 1206 1 0K OHM 1 4W 1 RESISTOR CHIP 1206 1 0K OHM 1 4W 1 RESISTOR CHIP 1206 1 0K OHM 1 4W 1 RESISTOR CHIP 1206 10K OHM 1 4W 1 RESISTOR CHIP 1206 10K OHM 1 4W 1
32. R CERAMIC 1nF 5 50 P2 5 TC CAPACITOR CERAMIC 1nF 5 50V P2 5 CAPACITOR ELECTROLITC VERT 105 C 1001 25V D8 CAPACITOR ELECTROLITC VERT 105 C 2201 35V 010 CAPACITOR POLYESTER 1 0nF 10 100V P5 CAPACITOR POLYESTER 2 2nF 10 100 5 CAPACITOR POLYESTER 4 7nF 10 100V P5 CAPACITOR POLYESTER 100nF 10 63V P5 CAPACITOR POLYESTER 100nF 10 63V 5 CAPACITOR POLYESTER 470nF 10 63V P5 CAPACITOR TANTALIUM 2 2 uF 25V P5 CAPACITOR TANTALIUM 4 7 16V P5 CAPACITOR TANTALIUM 4 7 16V P5 DIODE RECTIFIER 1N4004 SI 1A 400V DIODE SIGNAL 1N4148 51 DO 35 DIODE SIGNAL 1N4148 SI DO 35 DIODE SIGNAL 1N4148 SI DO 35 DIODE SD103A SI SCHOTTKY RECT 40V 0 5A DIODE ZENER 1068 400mW 6 8V DO 35 DIODE ZENER 1112 400mW 12V DO 35 INTEGRATED CIRC NE5532 DIP8 2 LOW NOISE OP AMP INTEGRATED CIRC TLC274 DIP14 4 LCMOS OP AMP INTEGRATED CIRC TLC274 DIP14 4 LCMOS OP AMP PIN STRIP 2 54 M 6x6 DIR 20040 POLES PIN STRIP 2 54 M 6x6 DIR 20040 POLES RESISTOR RS2F 100 10 0 OHM 1 2W 1 RESISTOR RS2F 475 47 5 OHM 1 2W 1 RESISTOR RS2F0100 100 OHM 1 2W 1 RESISTOR RS2F0100 100 OHM 1 2W 1 gt 4 RESISTOR RS2F0412 RESISTOR RS2F0619 RESISTOR RS2F0619 RESISTOR RS2F0681 RESISTOR RS2F 1100 RESISTOR RS2F 1150 RESISTOR RS2F 1150 RESISTOR RS2F 1150 RESISTOR RS2F1182 412 OHM 1 2W 1 619 OHM 1 2W 1 619 OHM 1 2W 1 681 OHM 1 2W 1 1 00K OHM 1 2W 1 1 50K OHM 1 2W 1 1 50K OHM 1 2W 1 1 50K OHM 1 2W 1 1 82K OHM 1 2W 1 R52 RESISTOR RS2F1280 2 80
33. RED DURING NORMAL OPERATION TAMPERING WITH INTERNAL SETTINGS VOIDS THE WARRANTY MAY HARM THE UNIT AND JEOPARDIZE THE GUARANTEED PERFORMANCE IN ADDITION MANY MODULES ARE TOO MUCH SPECIALIZED AND DIFFICULT TO REPAIR EVEN BY SKILLED TECHNICIANS AND MUST BE REPLACED IN CASE OF NEED BY BRAND NEW ONES AND POSSIBLY RETURNED BACK TO FACTORY TO VERIFY IF THEY CAN BE REPAIRED ANY ISPECTION ON THE MODULES DESCRIBED ABOVE MUST BE EXECUTED WITH THE TOP COVER REMOVED AND OFTEN WITH THE OPERATING UNIT CONNECTED TO THE MAINS ALTHOUGH MOSTLY OF THE PARTS UNDER VOLTAGE ARE INSULATED AND NOT EASILY ACCESSIBLE THIS EXPOSES TO THE RISK OF ACCIDENTAL CONTACT WITH THE MAINS VOLTAGE TO AVOID IT ALWAYS USE INSULATED TOOLS AND NEVER TOUCH THE SUPPLY TRANSFORMER THE MAINS SWITCH OR THE MAINS SOCKET WITH MAINS CONNECTED NEVER OPERATE THE EQUIPMENT WITH THE COVERS REMOVED REMOVAL OF THE BOTTOM RF COVER MA Y LEAD TO IMPROPER FUNCTIONING OF ANY ELECTRONIC MEASURING METER DUE TO HIGH RF FIELD MAINS VOLTAGE MA Y KILL PAGE 16 6 3 Thepowersupply components The power supply components other than the boards below described are very few mainly the power transformer with a power relay a bridge rectifier and a power capacitor which delivers the raw rectified de power to the SMPS regulator module The unregulated de voltage nominally 140 Vdc may range 120 170 V The primary tap on the power transformer 15 factory set on the 230V input allowi
34. S M RESISTOR S M 2M2 1 4W P 6 35 1K 1 4W P 6 35 1K 1 4W P 6 35 1K 1 4W P 6 35 1K 1 4W P 6 35 1K 1 4W 6 35 1K 1 4W P 6 35 1K 1 4W P 6 35 1K 1 4W P 6 35 1K 1 4W P 6 35 5K1 1 4W P 6 35 1K6 1 4W P 6 35 75 1 4W P 6 35 43K 1 4W P 6 35 A E E E E E E ES a a a E E E E Qk Qa Q U S E ES E E E E A E ES EE R38 R44 R59 R44 R75 R76 R84 R85 R36 R46 R53 R35 R39 R60 R41 R54 R87 R42 R51 R68 R82 R83 R43 R45 R61 R47 50 58 R63 R67 R69 R73 R74 R78 R79 R80 R86 R88 R89 R94 R95 R96 R97 R98 RV1 RV2 RV3 RV4 U1 U3 U4 U5 U6 07 08 RESISTOR 5 RESISTOR 5 RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M 3K3 1 4W 0 25 25PPM P 6 35 RESISTOR S M RESISTOR S M RESISTOR S M RESISTOR S M 4K3 1 4W P 6 35 4 7 1 4W P 6 35 4 7 1 4W P 6 35 4K7 1 4W P 6 35 4 7 1 4W 6 35 4K7 1 4W P 6 35 4 7 1 4W 6 35 1 4W 6 35 22 1 4W 6 3
35. STOR S M 4K7 1 2W RESISTOR S M 4 7 1 2W RESISTOR S M 4 7 1 2W RESISTOR S M 4 7 1 2W RESISTOR S M 4 7 1 2W RESISTOR S M 4 7 1 2W RESISTOR S M 4 7 1 2W RESISTOR MET OXIDE 47K 2W 5 P 17 5 RESISTOR S M 47 1 2W RESISTOR S M 151 2W RESISTOR S M 151 2W RESISTOR S M 151 2W RESISTOR S M 151 2W RESISTOR S M 151 2W RESISTOR S M 151 2W RESISTOR S M 2K2 1 2W RESISTOR S M 2K2 1 2W RESISTOR MET OXIDE 6 8 2W 2 P 20 RESISTOR MET OXIDE 2K2 3W 5 P 22 5 RESISTOR MET OXIDE 4K7 3W 5 P 22 5 RESISTOR MET OXIDE 4K7 3W 5 P 22 5 RESISTOR MET OXIDE 4K7 3W 5 P 22 5 RESISTOR MET OXIDE 4K7 3W 5 P 22 5 OMITTED SCR S2065K LOW OHM WIRE RESISTOR D3mm L 23 LOW OHM WIRE RESISTOR D3mm L 23 LOW OHM WIRE RESISTOR D3mm L 23 Ba 428 ey da ee oaks E Gan Gk Gas Sek 25 es E E ea E ea tau SESA E SH4 LOW OHM WIRE RESISTOR D3mm L 23 1 SH5 LOW OHM WIRE RESISTOR D3mm L 23 1 SH6 LOW OHM WIRE RESISTOR D3mm L 88mm 1 T1 TRANSFORMER 1 TA1 TRANSFORMER 1 TA2 TRANSFORMER 1 SRFB1KOPB2 2 PORT RF OUTPUT COMBINER 8 LPF REF DESCRIPTION C2 AUXILIARY PRINTED CIRCUIT C1 AUXILIARY PRINTED CIRCUIT CAPACITOR CHIP CERAM 1206 5 100 CAPACITOR CHIP CERAM 1206 5 100 5 CAPACITOR CHIP CERAM 1206 47 5 100 C4
36. are immediately accessible or needs a minimum of dislocation of other components and plates Only the RF boards need a deeper look RF boards are delicate modules which contains some parts as flanged power transistors and resistors which must separately be screwed on the supporting heatsink and may be easily damaged by improper handling These boards are the 500 W power amplifier modules and the RF output combiner Repairs of these modules are usually made in the factory or in a specialised laboratory if possible at all If the p c board is damaged perhaps only the costly RF active devices may be recovered Nevertheless very often this is worthless because in case of major damages these parts are internally electrically damaged or degraded Repair of the RF modules requires too at the end of the reparation a full check of the module s working parameters in a dummy fixture or in a test assembly which are not available even in most specialised laboratories For these reasons repairs of the modules specially the higher power amplifiers is discouraged at the most and the broken one must be replaced by new parts with the PAGE 21 same identical characteristics fully tested at the factory To replace the modules avoiding as much as possible to damage the new part or the old transistors if not already broken carefully follow the subsequent steps 1 Remove the amplifier cabinet from the rack after having disconnected from its rear conne
37. be over hauled when the Unithas been working at high temperatures over 30 35 Never change or cause the original settings to be changed when the necessary complex testing equipment and standard calibration procedure are not available 5 WARRANTY Like all NICOM s solid state equipment the NA 501 carries a 2 year Warranty on all its components with the exclusion of the final RF power module which may be damaged by faulty output connections This warranty is null and voidif the Unitis tampered with failure 15 due toimproper use wrong installation or external causes suchas mains overvoltage This warranty covers work done exclusively in our laboratories and in those of our agreed representatives The goods shall be delivered carriage prepaid to the laboratory and shall be returned freight forward This warranty does notcover any consequential damage due to non operation or faulty operation PAGE 14 6 SERVICE MANUAL 6 1 SYSTEMDESCRIPTION 3 basic sections compose the NA 501 the RF amplifier box the power supply and the control and metering section The RFsection comprises 1 500W amplifier modules connected through strip linecombiners All the RFtransistors Mos Fet type A low pass filter with directional coupler completes the section whichis completely screened by a metal box tocomply with EMI requirements A fully planar design permits an immediate access and inspection to the 2 internal modules The
38. board fixing screws 10 Remove the broken module and clean the supporting heatsink base plate before mounting the new one 11 Smear thin heat conductive silicon grease below the flanges of the power transistors and resistors of the new module before mounting it 12 Position the new module placing the threaded spacers and screws over the p c board avoiding to tighten them When all the screws are placed control the correct alignment of the transistors and resistors fixing holes and tighten the screws and spacers 13 Insert the proper screws and washers if any across the transistors and resistors and carefully tighten them in several alternate steps 14 Reconnect the power supply and bias cables to the module 15 Turn on the whole amplifier fully connected to the supporting power and control rack without RF power with RF load connected and driver exciter off Enable the equipment with the exciter still off 16 Measure the bias current of the two transistors on the module as explained on previous paragraphs 4 and 5 They were factory adjusted to 100 mA 1mV 17 If the currents are off the range 50 200 mA 0 5 2 mV carefully retouch the bias trimmers on the board A small clockwise rotation increases the bias current 18 Reduce the output set power to a low value acting on the front panel power set trimmer and turn on the exciter power 19 Slowly increase the power set and measure the balance of the current dra
39. commended values are 1 5 to2 5 mm squared Donever switch the Unit on without antenna connection even when no RF drive is on 3 4 ANTENNA CONNECTION N output connectoris fitted at the back of the amplifier module Itis very important to check that the antenna the connecting cables and the connectors are suitable for 500W The antenna coupler too should be capable of adequate power its input connector shall be PAGE 9 3 5 LF CONNECTION maximally avoid earth loops wire the modulation signal line directly on the exciter withhigh quality shielded and preferably balanced cable Ground the shield only on the exciter LFinput 3 6 OTHER RECOMMENDATIONS The ambienttemperature shall range between 5 C and 30 C 35 C max peak Itis advisable tohang amin max thermometer on the wall to display any variation Airconditioning at20 25 C would obviously be the best solution but installation and operating costs are generally excessive Thermal isolation and efficient ventilation with athermostat controlled blower are generally the most advantageous solution Mains fluctuation and electric discharges due to the weather or nearby industrial machinery may cause significant trouble especially in mountain areas and in places close to industrial areas In such cases itis advisable if notindispensable to install a protector and insulating transformer or possibly an electromechanical mains voltage regulator NICOM can provide al
40. ctors the input and output cables the power supply and the control cables Disconnect also the ground cable from its screw 2 To investigate on the damaged parts or to test the reparation it may be required to externally connect the removed cables and the output load to the amplifier assembly in manner to permit inner inspection of the top and bottom of the Unit If the latter is placed on a small stand aside of the main rack the internal cables are usually long enough to permit the connections avoiding extension cables 3 Open the bottom cover of the cabinet and remove the screen from the damaged module s if any 4 If the damage is not immediately visible it may be helpful to measure the currents sunk by each 300W sub module amplifier To this aim a low ohmic value shunt resistor is inserted in series to the 48V power supply of the module s subsections R12 and R13 10mQ To measure the current sunk the amplifier assembly must be completely connected and powered with and without RF A sensitive RF proof digital voltmeter must be used to measure the voltage across the shunt resistors which vary from nearly mV at no load to 100 mV at full power Take care most of low quality digital or analog meters are not able to do this reading because they are affected by the high RF field and their reading is completely meaningless WARNING great care must be paid not to accidentally short circuit the resistor leads to the ground wi
41. decoupler and dampening components are mounted on the positi ve supply line of each amplifier plus a small value resistor R12 and R13 for possible separate current detection of each supply leg The gate bias is separately adjusted through R15 and R16 on each section Do not tamper the factory bias preset values The full power output of the whole module exceeds 600W to provide some room for coupling losses on the combining stages of higher power amplifiers like the same NA 501 PAGE 19 6 8 Theoutput RF power combiner LPF and coupler This module is symmetric to the input power splitter and is another printed Wilkinson coupler whose power management capability is obviously much higher than the input board In this case the power balancing resistors are high power devices whose centre connection is referred to ground through an inductor which discharges any static electricity on the antenna up to a relevant amount of power The power combiner is followed by a printed low pass filter which attenuates the harmonic products generated by the amplifiers 3 directional sample lines derive two rectified voltages proportional to the direct and reflected output power and a RF signal for external monitoring purposes PAGE 20 7 REPAIR AND REPLACEMENT OF DAMAGED MODULES The NA 501 is a high reliability Unit as much effort was done in the design and development stage to assure the maximum reasonable working margin for each part Neverthe
42. ed ventilation air flux It is not permitted to insert the equipmentin a closed rack withouta suitable external air extraction system An auxiliary IEC 320 female type mains outlet is provided which is powered only when the amplifier is on to supply the exciter No fuses other than the general fuses 16A are inserted on this line Limit the power absorption from this outlet to low levels i e 100W max W WARNING Setting the mains voltage for 115 or 230V operation requires to gain access to the inner of the equipment removing the top cover Be sure to remove the power cord from mains to avoid direct exposure to hazardous mains voltage which are always present on the fuses and the input board even with power on switch in the off position PAGE 5 2 3 TECHNICAL SPECIFICATIONS 1kW output if not otherwise specified Frequency range 87 5 108 MHz RFinputpower 8W nom 10 W max RFoutput power 500 W 0 5 dB RF input output impedance 50 Q RF input connector N RFoutputconnector N RF monitor connector BNC Harmonic and spurious emissions lt 70 4 monitor attenuation 54 dB typ Max total current handling capability on the auxiliary socket 1A 230 Vac 100Wmax not fused Mains supply requirements 115 230 Vac 50 60 Hz lt 950W 1250 VA Operating temperature range 0 35 C recommended 10 50 C max Dimensions not including the handles 483 x 177 x 5
43. egative bias to completely disable the RF power if needed The positive regulator TR4 derives the positive 11 3V board supply from the 48V regulated line 6 6 RF power splitter The purpose of this simple board is mainly to divide the input RF drive power in two identical signals one for each power amplifier module providing a good insulation between each output port gt 20 dB typ 23 dB minimum on the whole FM band This is done by a Wilkinson type printed coupler followed by the balancing resistor array R21 R24 A directional coupler senses the input RF level and RT1 is regulated to provide the overdrive protection circuit trip at the right maximum input level The board supports also the direct or forward and reflected detector sensitivity trimmers whose input comes from the output board Two additional lines support the RF module bias or AGC line and the temperature sensing PTC thermistor 6 7 TheRF power amplifier module This module is built around a couple of Gemini type Mos fet transistors each one forming a 300W push pull amplifier Discrete Wilkinson type couplers equip both the input and the output module section doing the job of dividing and recombining the input and output signals providing a suitable insulation between the transistors A small balancing resistor R1 is mounted on the input splitter while a much bigger resistor R14 is mounted in the output combiner A group of C R and L RF
44. ight however flash briefly at low power when firstly tuning the input of an NA 501 driven tube amplifier or a cavity band pass filter Temperature led on This led turns on when the internal temperature is excessive Reduce environment temperature and increaseroom ventilation In this case itis important that the hot air released by the Unit be exhausted Control regular functioning of the internal ventilation fans and clean any externally applied dustfilter ifany PAGE 13 4 SERVICE AND MAINTENANCE Since the NA 501 is cooled by air itis subject to clogging by dust Because of the high quality materials used in their manufacture ifitis installed as setforthunder INSTALLATION AND USE itwill notrequire special maintenance for quite some time Aregular service routine mainly toremove internal dustis suggested over a6 year rate Take present that 90 of the air circulation is restricted to the main internal ventilation channel and donotaffect the components Regularly change the ventilation fan especially in higher temperature environments 2 yearrate may be prudential always usethe same high quality ball bearing fan type After a few years of continuous service itis recommended that the Unit be overhauled in the factory orina specialised laboratory where the characteristics can be checked against the initial ones and recalibration can be made when needed Itis also especially important that the power supply
45. ined by each module at half level and at full power Verify the limits written in paragraph 5 PAGE 23 20 Turn off the equipment reassemble screening covers and bottom panel of the Unit and reposition it in its working location with full connections 21 Perform limited period of test at full power i e 500 550 W and then reduce power at maximum nominal working level 1 e no more than 500 W PAGE 24 NA 501 AMPLIFIER FRONT TOP INTERNAL VIEW D OnO Ea NS RFL POWER O y SBS
46. l these accessories on request Since the total cost of the plant inclusive of broadcasting equipment antenna system and installation is rather high a certain percentage of the budget should be estimated for buying and installing suitable protection and conditioning facilities as described above Depending on location the share of total cost should be around 20 30 with this expenditure however the machinery will operate under optimum conditions its useful lifespan will increase and above all the incidence of accidental breakdowns due to ambient or mains trouble will be reduced PAGE 10 WARNING OPERATION WITHOUT THE ANTENNA OR WITH FAULTY ANTENNA CONNECTION MAY CAUSE DEGRADATION AND POSSIBLE DESTRUCTION OF THE FINALSTAGE THIS FAILURE IS NOT COVERED BY THE WARRANTY AVOID TO USE TOO POWERFUL EXCITERS AN INPUT POWER HIGHER THAN 12W MAY PERMANENTLY DAMAGE THE RF TRANSISTOR CAUSING A COSTLY DAMAGE WHICH IS NOT COVERED BY THE WARRANTY A STABLE AND PROPERLY REGULATED 20 25 EXCITER LIKE NICOM S NT20 or NT30 ARE THE BEST CHOICE 501 driven by atypical NICOM exciter generates a very clean RF output Neverthless if any strong RF signal coming fromnerby transmitters 1s coupled to the antenna itmay cause intermodulation in the output transistors and generate spurias In this case a tuned output filter may be required to remove the problem Itis mandatory to provide adequate venti
47. lation to the Unit to maintain its internal temperature as low as possible in the recommended range 5 25 C Even if the Unit may sustain 45 C and occasionally slightly highertemperatures his life expectancy will be impaired by high temperature As general rule the life expectancy may be halved by each 10 C increase in ambient temperature over 30 C PAGE 11 3 7 OPERATION Check that the antenna the subsequent power amplifier or a suitable dummy load is connected to the amplifier RF output Ifthe NA 501 drives atunedtube amplifier check that the input of the power amplifier is already tuned on the wanted frequency Control that the power cords are correctly connected to the amplifier and its driver and both the Unitare off Before connecting to the amplifier control that the exciter power is set at zero ora very low level lt 1 W and the frequency is correctly set Check that the exciter output signal is fed to amplifier input then 1 Switch on the power on switch on the NA 501 theswitch will glowred Internal blowers will start Noledshouldlighton NoRF output power should be present 2 Properly position the meter switch to observe the RF output increasing on the amplifier 3 Switch on the power on switch on the exciter 4 Slowly raise the drive power to the required level i e 8 10W The RF output power should rise from zero to the nominal 500 Watt if the output power adjustmentis set is to maximum on the a
48. less as all Unit which works 24 hours a day for years some failures are possible especially in those environments which over stress the Unit like hot or dusty or moist places or subjected to wide mains fluctuations or static discharges and things like that In the event of any failure an appropriate analysis must be done to avoid subsequent failures due to faulty ambient conditions A often underestimate cause of failure is simply a too high ambient temperature or insufficient ventilation Improving the ambient and system ventilation as suggested in the installation paragraph of this manual usually fix the problem Other obvious causes may be dust clogging and ventilator fan failure A regular service and maintenance routine will avoid these sources of problems and it is suggested to change the ventilator each two years even if no damage is still visible especially at high ambient temperature No air pipe must be attached to the ventilator fan output for air ducting if an external extacting fan 15 not installed in that system In any case if the amplifier fails some work must be done on the Unit to fix the problem With the appropriate spare parts most of repairing work may be done on site without need of special tools and often without need of any solder joint Not much needs to be said about the general boards and components changing virtually all of them may be changed in few minutes without retouching the adjustments Most of them
49. mplifier front panel Noledshouldlighton Asageneralrule the input power must be 20 higher than the minimum level required to the full output power i e 8W if 10W are enough to obtain 500W on the output 5 Control and note for future reference the correct reading of the operating parameters through the internal instrumentation which must indicate the following values FORWARD POWER up to 500W REFLECTEDPOWER lt 50 W typ 0 20W REGULATED VOLTAGE 48V 300V meterrange UNREGULATED VOLTAGE 140V 15 Some amplifiers donotpermittoread the regulated and unregulated voltage on the internal meter The installation of the amplifieris thereby completed spectrum analysisisnow advisable to assure no spurious products due to internal orexternal causes i e reverse intermodulation on the final stage are generated Nicom wishes you success in your work and remind you that they are always available for further information orto tackle any specific problem PAGE 12 3 8 POSSIBLEMALFUNCIONS Noledalarmmustbeon duringregularfunctioning following isa listof possible malfunctions causes VSWR led on This led turns on when the reflected output power exceeds the 40 50 W threshold In this case do not operate the system and check antenna relevant wiring and connectors When the Unitis connected to asuccessive amplifier re tune the latter s input to obtain the smallest reflected power This light should never turn on it m
50. ng a mains range approximately 200 250 Vac Should mains voltage be 240 nominally it is suggested to change the transformer tap to that voltage If mains voltage is a stable 215 225 Vac the transformer tap may be left as factory set Only if there are frequent occasional drops of mains input below 195 and consequent system stops it is suggested to lower the input tap to 220V To do that the power cord must be disconnected from the mains the top cover must be removed and the transformer voltage terminals may be accessed An USA version is provided with a someway different transformer and general wiring see the appropriate electrical diagram and internal layout In this version some jumpers must be preset on the equipment s internal terminal board to provide 115 or 230Vac operation if not factory wired In details these settings are 220 Vac 1 P3 to 3 P4 115 Vac 3 P3 to 3 P4 and 1 P3 to 1 P4 6 4 TheSwitch Mode Power Supply regulator This module performs an efficient regulation of the raw dc input nominally 140V 15 to a lower 48V 11 Being its efficiency very high very little heat is produced in the regulation process The nominal current capability of the regulator 15 much higher than requested and approaches 40 48V A control I O connector an upper daughter board permits a remote control of the regulator
51. rimmer the RF output power may be varied to values different from that factory preset Never exceed safe 500W on RF output even if the amplifier is usually able to easily threpass this limit to have some safety margin The output of IC4d constitues the AGC line which is buffered by ICS to drive the RF transistor gates Both the two sections of IC5 are in parallel to increase the current capability of the external AGC line The reflected power protection is managed by which compares the reflected sensed signal to a fixed threshold which is set to 40 SOW as determined by R35 and R36 The output of IC3 adds on the internal AGC line though D14 The action of this circuit is proportional i e the output power is continuously decreased till the fraction which is reflected back no more exceeds the safe maximum level There is no RF complete switch off even with severe load mismatch Both direct and reflected signal lines are conveyed to the remote connector through insulating 10kohm resistors The temperature protection on the output stage is performed by IC4b which trips when the temperature sense line crosses its preset threshold completely disabling the RF output The tem perature sensor is mounted on the heatsink near the RF transistors and is constitued by a precise PTC resistors which varies its resistance accordingly to the temperature PAGE 18 On this board a small negative rectifier and regulator 5 provides n
52. room shall haveaminimum flow rate of 500 metres cubed per hour or more If the Unitis fitted in arack system the back door of the rack cannot usually be fixed in place acompletely closed assembly is needed a suitable ventilation extraction unit must equip the system Toaidair ducting an optional flange may be retrofitted on the ventilation outlet to which duct can be attached to convey hot air outside In this case remember that the NA 501 internal fans are low pressure units some sort of external air extraction blower is than imperative on the exhaust air duct Vents in the walls and any other openings shall be fitted with a metal grating to keep rodents out and with a dust filter Make absolutely certain that no water can seep through the vents or the air exhaust duct or antenna cable grommet and that the floor cannot be flooded during heavy rainfall If notimpedited by properairfiltering insects in some location may be conveyedin the internal heatsink accumulating on it and finally obstructing it causing overtemperature alarm Even moisture and or dust when contained in the air orin the room in excessive quantity may cause condensation build up in the amplifier When the system 1s periodically switched on and off this can trigger destructive electric arcs and short circuits and thus cause damage that is not covered by the guarantee PAGE 8 3 3 WIRING INTO THE MAINS The NA 501 is powered by a single phase line Mains capaci
53. ted power supply voltage 300Vdcf s The 2 led s light only in case of failure The meaning of these led is summarised on the following table LED MEANING VSWR High RF output reflected power gt 50 60 W TEMPERATURE High internal temperature probably due to high environment temperature or failure of the ventilation system Table 1 warning led meaning PAGE 4 2 2 THE REAR PANEL AND THE CONNECTIONS 0678 O REMOTE CONTROL N f n NANO f f AE L The rear panel allocates RF power and the I O ports in addition to mains power cord and fuse the earthling screw and an auxiliary mains socket on some models The power cord is not removable Ifitis required a longer cable than that provided in the factory roughly 2 meters long a suitable 1 5 mm sq power cord may easily replace the original one The fuse has a different rating for 115 or 230Vac operation be sure to adopt the right type for your mains network The Antenna output is brought out ona type connector the inputconnectoris also a N type Aremote I O portis available ona SUBD 25 poles female connector The exhaust air output opening must not be obstructed during operation wide room must be provided during installation to permit a substain
54. th the voltmeter probe tips during measurements 5 When properly functioning at full power each module 300W subsection will sink 8 10 Amperes i e 80 100 mV across the shunt resistor The absorption must be balanced 10 around the mean value on each amplifier A lower or higher value may mean a module failure 6 Remove the power supply cable screwed on a centre terminal in the board and the small bias cable 7 Unscrew the input and output RF connections at the module opposite sides 8 Carefully unscrew the RF transistor flanges from the heatsink base plate This operation if not properly done may mechanically over stress the transistor cracking the internal de licate beryllium oxide ceramic which supports the active silicon dies and determine unrecoverable PAGE 22 damage of the device CAUTION beryllium oxide is toxic and must not be thrown with domestic refuse but in specialised toxic material disposals No special handling precaution must be paid when the transistors or power resistors are not mechanically broken apart those deriving from the handling of mechanically fragile and very costly devices If the transistor or resistor flange 15 broken avoid to get in touch with it and the brittle white exposed internal ceramic or inhaling dust of it Dispose the transistor or the entire broken module as previously described 9 Make a note of the position and the length and remove the threaded screen spacers and the
55. ty must be atleast2kVA and nominal voltage is 230Vac In some countries where 115 is norm this voltage must be internally set in the factory or by skilled people before installation While the power supply regulator accepts a wide input voltage 190 250 Vac operation near the lower input voltage on high impedance lines must be avoided if the line drops more than 10 volt at full load the low line sense circuitry may trigger an oscillating turn on turn offcycle whichis very dangerous In this cases adoptan external line stabiliser The nominal mains input range 190 250 Vac is achieved when the primary side of the main transformer is wired to the 230 V tap Two other taps the first one slightly lower 220 V the second higher 240 V are available to adjust the input voltage range of 10 V In countries were a stable 240V 15 the norm itis important to set this tap on the transformer In this case the allowed voltage range window mustbe shifted higher to avoid nuisance trip at occasional higher mains voltage See proper section in the service section of this manual Toensure proper operation and comply with the safety regulations efficient earthling is required Use the yellow green lead inthe power cable Thecable s neutral lead is blue Neverconnect the earth tothe mains neutral lead Thecableconnecting the NA 501 mains input terminal block to the external board should consist of leads of adequate cross section Re
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