Lexicon LXP-5 Service Manual

Performance
Verification
Lexicon
Static Electricity
Precautions
Clocks and
Power Supply
Measurements
Equipment Required
Variac
DMM
Frequency Counter
(50MHz)
50 MHz Oscilloscope
Many of the LXP-5’s internal components are extremely sensitive to static
electricity. The following practices minimize possible 1C damage which can
result from electrostatic discharge.
1. Don't handle ICs and boards any more than is necessary.
2 . Discharge personal static by touching the LXP-5 mainframe before
handling ICs or boards.
3. Handle each 1C by its body.
4. Do not slide ICs or boards over a surface.
5. Avoid having plastic, vinyl or styrofoam in the work area.
6 . Handle ICs only at a static-free workstation.
7. Use only grounded-tip soldering irons.
8 . Use antistatic containers for handling and transport.
Remove the two screws from the LXP-5 front panel and the center screw from
the rear panel. Remove the 5 hex nuts from the 1/4" phone jacks on the rear
panel. The pc board should now slide outtowards the front of its case, allowing
easy access to the circuitry.
1. Plug the LXP-5 power pack into the Variac and set output for 120 VAC.
2. Set the DMM to measure VAC. Apply power to the LXP-5 and measure the
voltage across C25; it should measure between 9 and 11 VAC. If measure¬
ment is below 9VAC, the power pack may be faulty.
3. Setthe DMM to measure VDC and check the regulated voltages for proper
levels:
Location: Power/Ground
Allowable voltage range
U25 pin 3/U25 pin 2
11.40 to 12.60 VDC
U26 pin 3/U26 pin 1
-11.40 to -12.60 VDC
U24 pin 3/U24 pin 2
4.75 to 5.25 VDC
U1 pin 14/pin 7
4.25 to 4.50 VDC
U38 pin 16/pin 8
6.75 to 8.25 VDC
U38 pin 7/pin 8
-6.75 to -8.25 VDC
4. P ower off the LXP-5 and measure DC voltage across battery BAT1 with
DMM; it should be 3.00 VDC or greater. If voltage is low, replace the battery.

Lexicon LXP-5 Specifications

General

Brand	Lexicon
Model	LXP-5
Category	Recording Equipment
Language	English