VJ1000
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USER MANUAL
Rev. 3.0 - 26/02/01
REPEAT STEPS 7 AND 8 SEVERAL TIMES TO OBTAIN THE OPTIMUM SETTINGS
9)
Increase exciter power until an output power of 800/850 W is obtained and repeat steps
7 and 8.
10) With output power at 1000 W, make small adjustments, as above, to minimize grid and
anode currents; if necessary, reduce exciter power to maintain 1000 W of output power.
8.2
Calibration of the Protection Card
Before calibrating the protection board, or IG and IA currents, remove the front panel
which also supports the RF chamber.
Disconnect the antenna output cable, remove the coaxial cable from the input connector,
undo the 8 screws holding the panel and remove the panel; take care not to disturb the high
voltage cables and the multipolar service cable.
Lay the chamber carefully on a raised surface, opposite the unit to facilitate the following
procedure.
The protection board has three trimmers for adjusting the following alarm thresholds:
insufficient fan pressure, excess V.S.W.R. and excess grid current.
These alarm conditions are indicated by three leds (Alarms Fig.1).
Remove the metal cover of the protection box by undoing the 4 screws.
The alarm thresholds may be calibrated through the following procedure:
1)
CALIBRATION OF FAN PRESSURE ALARM THRESHOLD (PRESS.).
a)
Switch the ST.BY. switch (15 Fig.1) to ST.BY.
b)
Enable power to the unit by switching the POWER switch (16 Fig.1) to ON.
c)
Ensure that the PRESS. indicator (11 Fig.1), initially on, turns off when the air-flow
switch (3 Photo3), positioned inside the flue, switches up (air pressure normal).
Two error conditions can prevent the above sequence from being completed: the indicator
remains on, or remains permanently off.
In this case adjust the trimmer, R4, until the sequence is completed correctly: switch
down, led on; switch up, led off.
2)
CALIBRATION OF V.S.W.R.
To adjust the threshold of the V.S.W.R. alarm first perform SETUP1 (Fig.3). The threshold
should be set at around 10 % of the maximum output power i.e. of 100W.
a)
Connect a mismatched, dummy load (e.g. 25 Ohms 1.5KW) to the RF output of the
amplifier, in series with a bypass wattmeter.b). With the unit switched on (N.B. the rear
cover must be in place) and having calibrated the unit to its exciter frequency, gradually
increase the output power from 0W until a reflected power of 100W is registered on the
external wattmeter.
c)
Adjust the trimmer R7 until the alarm threshold is reached and the V.S.W.R. led lights
up (10 Fig.1).
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Summary of Contents for VJ1000
Page 1: ...Prodotto da Italia VJ1000 User Manual www DataSheet4U com ...
Page 18: ...VJ1000 14 40 USER MANUAL Rev 3 0 26 02 01 FIG 1 www DataSheet4U com ...
Page 20: ...VJ1000 16 40 USER MANUAL Rev 3 0 26 02 01 FIG 2 www DataSheet4U com ...
Page 24: ...VJ1000 20 40 USER MANUAL Rev 3 0 26 02 01 PHOTO 2 1 2 3 4 5 6 www DataSheet4U com ...
Page 38: ...VJ1000 34 40 USER MANUAL Rev 3 0 26 02 01 SETUP 1 FIG 3 www DataSheet4U com ...
Page 39: ...VJ1000 35 40 USER MANUAL Rev 3 0 26 02 01 SETUP 2 FIG 4 www DataSheet4U com ...
Page 40: ...VJ1000 36 40 USER MANUAL Rev 3 0 26 02 01 SETUP 3 FIG 5 www DataSheet4U com ...
Page 47: ...VJ1000 Flat Cable 1 2 Appendice Tecnica Rev 1 0 26 02 01 www DataSheet4U com ...
Page 49: ...VJ1000 Telemetry Cable 1 2 Appendice Tecnica Rev 1 1 26 02 01 www DataSheet4U com ...
Page 51: ...VJ1000 Power Supply 1 4 Appendice Tecnica Rev 1 0 26 02 01 www DataSheet4U com ...
Page 52: ...VJ1000 2 4 Power Supply Technical Appendix Rev 1 0 26 02 01 www DataSheet4U com ...
Page 55: ...VJ1000 H T Rectifier Board 1 4 Appendice Tecnica Rev 1 0 26 02 01 www DataSheet4U com ...
Page 56: ...VJ1000 2 4 H T Rectifier Board Technical Appendix Rev 1 0 26 02 01 www DataSheet4U com ...
Page 59: ...VJ1000 R F Block 1 4 Appendice Tecnica Rev 1 0 26 02 01 www DataSheet4U com ...
Page 68: ...VJ1000 2 4 Grid Plate Meter B Technical Appendix Rev 1 0 26 02 01 www DataSheet4U com ...
Page 72: ...VJ1000 2 4 Low Pass Filter Technical Appendix Rev 1 0 26 02 01 www DataSheet4U com ...
Page 75: ...VJ1000 Input Matching Circuit 1 4 Appendice Tecnica Rev 1 0 26 02 01 www DataSheet4U com ...
Page 76: ...VJ1000 2 4 Input Matching Circuit Technical Appendix Rev 1 0 26 02 01 www DataSheet4U com ...
Page 80: ...VJ1000 2 4 Directional Coupler Technical Appendix Rev 1 0 26 02 01 www DataSheet4U com ...
Page 83: ...VJ1000 Telemetry Card opt 1 4 Appendice Tecnica Rev 1 0 26 02 01 www DataSheet4U com ...