R.V.R. Elettronica PTX30 UHT/S3, Руководство пользователя

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PTX30 UHT /S3
35 / 36 User Manual Rev. 5.0 - 10/12/2001
10.4 Power supply adjustment
The adjustments on the power supply after a replacement are the same performed
when a R.F. power module is changed.
Follow points 1, 2, 3, 4, 5, 6, 7, 8, of R.F. power amplifier replacement.
10.5 R.F. Power amplifier adjustment
• After the RF power module replacement, connect the setup shown in
(see figure 10.2).
figure 10.2
• Switch on the PTX30 and wait for the PLL to lock.
• Rotate clockwise trimpot PWR ADJ to obtain the maximum output power.
• Read the output power on the external wattmeter; if it isn’t 30W, adjust trimpot
R3 on the power supply board to obtain 30W.
• Select with switch the FWD PWR reading and check that the reading of PTX-
30 meter is 30W.
If not, adjust R21 on the anameter board.
• Disconnect the dummy load and you should notice a power output reduction at
about 12W, and the SWR lamp should light.
Connect a voltmeter across the terminals PD and PR of the rear panel telemetry
terminal board, and adjust R8 on the power supply for a reading of 0V ±0.1V.
• Adjust trimpot PWR ADJ for an output power of 10W read on the FWD PWR
scale, select the REF PWR scale with switch and adjust R16 on the anameter
board for a reading of 10W f.s.d.
• Reconnect the dummy load and rotate clockwise trimpot PWR ADJ checking
the output power of 30W.
10.6 Audio input card adjustment
No adjustments needed after board replacement.
10.7 CPU adjustment
After Cpu board replacement, check for proper performance of the display, the
UP, DOWN and ENTER switches by entering an operating frequency. Check also
the RS232 port.