R.V.R. Elettronica TEX150, User Manual

Page: 29 / 110

TEX150
23 / 40 User Manual Rev. 4.0 - 27/07/01
8.2 Removal of the Modules
NOTA: When the exciter is operated with the cover removed, hazardous voltages
and heavy current are accessible. Ensure all primary power is disconnected from
the exciter before attempting equipment maintenance.
To reinstall the card is enough to execute operations sequence in the opposite
way.
Remove all the screws that are located on the top and bottom covers of the machine.
After that the covers have been removed, extract, with the help of the chapters
8.1.1 and 8.1.2, all exciter modules.
8.2.1 Stereo encoder card replacement
• Open the top and bottom covers of the unit.
• Disconnect connectors J1, J3 and J4.
• Unscrew the four nuts fixing the card on internal chassis.
• Unscrew the screw inside the INPUT LEVEL knob and slide it off.
• Raise the card from its supports, simultaneously sliding the switches and the
INPUT L\EVEL switch pivot from the panel.
8.2.2 RF power amplifier transistor replacement
For this module it's only possible to replacement the transistors:
• Open the top cover of the unit.
• Open the top cover of the RF power amplifier.
• Unscrew the two fixing screws of the device (BGY33, MRF317 or SD1480).
• Remove the broken transistor.
NOTE: During replacement of broken devices it's necessary to pay attention to
device's pin position and insertion, to check that the device's fixing screws aren't
in short-circuit and to check that the soldering is good and without impurities.
NOTE: Interpose between devices and heat-sink an electronic silicone compound.
8.2.3 VCO replacement
• Open the top cover of the unit.
• Disconnect connectors CN1, CN2, J1, J3 and J4.
• Desolder the two wires connected on J2 and J5 of the VCO Card.
• Unscrew the fixing screws of the VCO card metal box on the internal chassis.
• Remove the metal box.