MultiDyne VAGC-100 - Manual (Page 5)

Instruction Manual, VAGC-100 DISASSEMBLY 5
NOTE
Use only a 1/4 Amp replacement fuse for 115 VAC operation. Use only a
1/8 Amp replacement fuse for 230 VAC operation.
FRONT PANEL CONTROLS and INDICATORS, VAGC-100
During normal operation the technician should be aware of the cable type in use and select it using the front
panel switch. When setting the equlization first turn the EQ BOOST switch on. If the cable being equalized in
shorted than 1000 feet, the VIDEO LED will glow red indicating over equlaization and that the fixed equalizer EQ
BOOST should be turned off. The front panel GAIN and EQ controls are for fine adjustments of video level and
equalization. During operation with an external battery the AC power supply will be bypassed.
DISASSEMBLY
!!!!!!!!!! CAUTION !!!!!!!!!!
HIGH VOLTAGES INSIDE. USE EXTREME CAUTION WITH THE UNIT OPEN.
SERVICE ONLY TO BE PERFORMED BY QUALIFIED PERSONNEL.
UN-PLUG POWER CORD BEFORE OPENING UNIT.
The disassembly process is basically the same for both portable and rack-mount units. First, remove the
power cord from the AC outlet. Remove the screw in the center of the front panel. Next locate the 2 screws on
the rear panel closest to the left and right edges. Please remove both screws. At this point the rear panel and bezel
will slide out with the main board connected. Be careful not to provide excess strain to the connecting wires
and coax. The unit can now be powered up on the bench without the chassis. Please take special care when
working near the power fuse. High Voltage is present near the fuse. Use extreme caution!
RE-ASSEMBLY
The re-assembly process is very simple. Slide the main board into to groves of the chassis. Do not bend
the wires more than necessary. The control and LEDs may need slight adjustment for alignment with the front panel
holes. Replace the screw in the center of the front panel fastening the bracket on the main board. Next, secure the
rear panel and bezel with the 2 screws on the left and right edges.
CALIBRATION
!!!!!!!!!! CAUTION !!!!!!!!!!
HIGH VOLTAGES INSIDE. USE EXTREME CAUTION WITH THE UNIT OPEN.
SERVICE ONLY TO BE PERFORMED BY QUALIFIED PERSONNEL.
UN-PLUG POWER CORD BEFORE OPENING UNIT.
For all calibration procedures, the VPDA-100 requires disassembly. Please see the section DISASSEMBLY
on page 5. The unit can now be powered up on the bench without the chassis. Please take special care when
working near the power fuse. High Voltage is present near the fuse. Use extreme caution!
Remove the instruments front panel or put the card on an extender for the plug in version and proceed as
follows. Connect a source of NTC7 composite to the input and terminate it at 75 Ohm. Adjust R33, front panel gain