MX-9331/URC

MX-9331/URC

REPEATER REGENERATIVE.
What is this?

Retransmit for wide band 16Kbps digital data (e.g. VINSON) ?
Recv fil (root Nyquist?) -> Adaptive threshold comparator
-> Clock recovery -> Re-sampling -> Xmit fil (root Nyquist?)

5 pin Audio conn. for handset.
14 pin X-MOD conn. (for COMSEC/TSEC device ?)
Two 26 pin conn. for RT.

What is 18.75Kbps ?

Four NICE relay

Four PCBs

PCB.1 & 3 SM-D-687705
U1/2/6/7/12:4029, U3:4030, U4:4023, U5/9:4011
U8/13:4013, U10:4001, U11:4049, U14:4024

PCB.2 SM-D-687706
U1:4015, U2/6:4030, U3/4/7:4011, U5:4019
U8:4029, U9:4013, U10:4024
Y1:3.30000MHz (18.75K x 176 ?)
Y2:2.81600MHz (16K x 176 ?)

PCB.4 SM-D-687707
U1:4013, U2:4001, U3:LM124D(Op-Amp),
U4:LM139D(comparator), U5:F7815(voltage regulator)

PCB.4 "NO Sync 18.75"