Emtron DX-3SP Specifications

OPERATING MANUAL EMTRON DX-3SP HF LINEAR AMPLIFIER February 2009 Emtron DIVISION OF EMONA ELECTRONICS PTY. LTD. 92-94 Wentworth Avenue, Sydney 201

10 Move the transformer close to the front panel (do not slide it – lift it and move). This will create more space at the back, so that the high vo

11 5 FRONT PANEL The following controls and indicators are present on the front panel: 5.1 Controls BAND SWITCH A nine position switch selects

12 ON Air - single LED, green. When pressing PTT, this LED turns on (while in OPERATE and READY). READY - single LED, yellow. Turns on at the end o

13 7 ELECTRICAL CONNECTIONS 7.1 Connections to Transceiver / Exciter Signal connections Before making any connections, ensure that DX-3SP is no

14 PLEASE NOTE: The DX-3SP should not be connected to a mains supply of less than 200VAC! Figure 6 Wiring for 230V shown as example Figure

15 8 DX-3SP DESCRIPTION 8.1 RF Section The RF section occupies the right hand side of the DX-3SP (looking from the top - front). See picture in

16 8.6 Antenna relay / QSK module The QSK module acts as an antenna relay controlled by the transceiver, via the control board. It switches the an

17 9 POWERING UP Before switching the power on, check all the necessary connections: Earth, Antenna, Transceiver, PTT. Make sure the 2 switches on

18 10.1.1 General For each band and operating frequency, the transceiver settings must match the position of the BAND switch on the front panel of

19 3. During the preliminary tuning, switch PTT on and off several times, to allow time for tube cooling. The tube dissipation (at a given drive le

2 INITIAL SETTINGS FOR PLATE AND LOAD CAPACITORS TEST FREQUENCY BAND FACTORY SETTINGS 50 OHM LOAD USER SETTINGS ANTENNA PLATE LOAD PLATE

20 If there is green Ig2- indication, for a given input drive, try to minimise it and even to obtain red indication. For this, it is likely that LO

21 10.2.3 Hints on good linearity and efficiency Operating with good efficiency: If you are watching the plate current indicator, you must be awar

22 If it is still not working, unplug the power cord from the mains, then remove the fuses from the fuse holders on the rear panel of DX-3SP and ch

23 In such a case, it is possible that the high voltage is still shown on the meter, but it does not reach the tube. In any case, this is a major f

24 14 GLOSSARY AC Alternating Current ALC Automatic Level Control AM Amplitude Modulation BALUN Balanced / Unbalanced Transfo

25 15 APPENDIX 1: SCHEMATIC DIAGRAMS 15.1 Block Diagrams 15.1.1 DX-3SP Block Diagram BackPanelPrimaryACpowercordLine 130 ampfuseLine 230 ampfuse

26 15.1.2 AC INPUT AND WIRING DIAGRAM Figure 8 Note: The 2 Y2 capacitors (4.7nF) are now on the PCB (On Chassis)MT2BlueNeutral/Ground1GBrown200

27 15.2 Circuit Diagrams 15.2.1 SOFT START Single Phase – Circuit Diagram Figure 9 NEUTRALR1a100/2WC10100nF+C5220uF/25VGATER6270kC112.2nFR113.9k

28 15.2.2 HIGH VOLTAGE POWER SUPPLY – Circuit Diagram Figure 10

29 15.2.3 RF Module Simplified 1832.2kRS13x150V1FU-728F140VA106330/13W10nF/1kV9-Way123456789A106220k10nF/1kVBIAS2BIAS13k100/13WV2FU-728FEBS(White

3 TABLE OF CONTENTS 1 GENERAL DESCRIPTION ...

30 15.2.4 RF output circuit 47pFQSKSw itchingANTENNA 17 301780L2 (Torroid)C150pFRF SENSORSW1-3151500pF80PLATE40 121720 308015250pF303300pF/10kV1

31 15.2.5 QSK – Circuit Diagram Figure 13 AMPR3100/1WD21N4148+C310uFCOAXIAL CABLE (thick)R1680R22k2RF DECK OUTCOAXIAL CABLE (thin)E M T R O ND3

32 15.2.6 RF Sensor INC7220pFC110pFREVC510pFDIRC1347pFD1D1N4148C410pFD2D1N4148C640pFR22.2kL2C210pFOUTR322/2WL1C340pFR42.2kC1010nFC1247pFC910nFR

33 15.2.7 DISPLAY BOARD – Circuit Diagram Figure 15 L63RL16YVR250kVR15kL76RC112.2nFL56YL52YR122k2L38GC61

34 15.2.8 CONTROL BOARD – Circuit Diagram Figure 16

35 15.3 Control Board and Adjustment Points The drawing below shows all the connections to the control board and the adjustment points. Unless you

36 15.3.1 Control Board Component Layout Figure 18 R20 TP4

37 15.3.2 Control Board – Solder Side Track work Figure 19

38 16 APPENDIX 2: WAVEFORMS 16.1 QSK Switching Figure 20 No “Hot switching”: The output relay (Top trace) switches first, and then the

39 17 APPENDIX 3: ADJUSTMENTS ADJUSTMENTS TO EMTRON DX-3SP AMPLIFIERS CAUTION Most of the following adjustments require the amplifier to be open

12 TROUBLESHOOTING - IF SOMETHING GOES WRONG... 21 12.1 NO POWE

40 There are 3 bias adjustment potentiometers: POT3 (BIAS), affecting both tubes and POT10 (BS1) and POT9 (BS2) only adjusting the bias to the tu

41 17.1.4 EBS ADJUSTMENT Adjustment: POT4, marked EBS Usually this adjustment is performed on 20m (14.200 MHz), but it can be done on any band.

42 the EG2 pin on the control board. While operating the amplifier at full power, by rotating the LOAD knob, IG2 can be varied and the screen volta

43 Figure 22 Control Board – Component side view 17.2 Display Board Adjustments The display board is pre-adjusted during testing. Howeve

44 Adjust potentiometer AMP for correct indication. 17.2.2 PLATE VOLTAGE Adjustment: VR2, marked: VOLT Using a voltmeter with a high voltage prob

45 17.3 RF Sensor (Bridge) Adjustment The amplifier is switched off for this adjustment. Check if adjustment is required as per following proce

46 Emtron DIVISION OF EMONA ELECTRONICS PTY. LTD. 92-94 Wentworth Avenue, Sydney 2010, Australia Tel. +612 921

5 DX-3SP LINEAR AMPLIFIER Serial No ………… OPERATING MANUAL January 2009 CAUTION 1 GENERAL DESCRIPTION The Emtron DX-3SP Linear Amplifier

6 1.1 DX-3SP – Internal View The main components of a DX-3SP amplifier are shown in the picture below. Figure 1 BAND SELECTOR PLA

7 2 TECHNICAL SPECIFICATIONS FREQUENCY COVERAGE: Complete (manually tuned) coverage of the nine HF amateur bands: 1.800 – 2.000 MHz 3.500 –

8 METERING: The front panel moving LED display systems indicate: “Moving light” LED indicators: • output power • reflected power • screen gri

9 3 UNPACKING The DX-3SP is packed in a heavy duty package easily sufficient to protect the amplifier during transportation, even in case of fair