CHAPTER 3: Installation
9
3.3 System Synchronization
A
SYNCHRONOUS
M
ODE
Strap the J6 jumper over the ASYNC pins. All attached equipment must be asynchronous. Turn the BIT RATE
rotary switch (BRI) to the correct system speed. No other adjustments to the PSD are necessary.
S
YNCHRONOUS
M
ODE
Strap the J6 jumper over the SYNC pins (this is the factory-default setting). All attached equipment must be
synchronous. There are four ways to synchronize the system:
1. Synchronization on the PSD’s internal clock.
• Main channel: Equipment attached to the main channel should be set to external clock.
• Sub-channel: Equipment attached to the sub-channels should be set to external clock.
• BIT RATE rotary switch: Set BRI to the correct system speed.
2. Synchronization on the equipment attached to the main channel.
• Main channel: Equipment attached to the main channel should be set to internal clock.
• Sub-channels: Equipment attached to the sub-channels should be set to external clock.
• BIT RATE rotary switch: Set BRI to the correct system speed.
• Jumper J7: If the equipment attached to the main channel is DCE, strap to NORMAL. If the equipment is
DTE, strap to FROM EXT DTE.
3. Synchronization on the equipment attached to sub-channel 1.
• Main channel: Equipment attached to the main channel should be set to external clock.
• Sub-channel 1: Equipment attached to sub-channel 1 should be set to internal clock.
• Sub-channel 2 through 8: Equipment attached to the sub-channels 2 through 8 should be set to external
clock.
• BIT RATE rotary switch: Set BRI to position 7 (CLK1).
• Jumper J7: If the equipment attached to the sub-channel 1 is DCE, strap to NORMAL. If the equipment
is DTE, strap to FROM EXT DTE.
NOTE: Synchronization on sub-channel 1 is not recommended when the device attached to sub-channel
1 operates in switched carrier mode. This will cause fluctuations in clock frequency and phase.
4. Synchronization on equipment attached to any sub-channel (PSD-8 only).
• Main channel: Equipment attached to the main channel can be set to internal or external clock.
• Sub-channels: Equipment attached to the sub-channels can be set to internal or external clock.