HP 3562A Service Manual page 359

C I RC U I T D E SC R I PT I O N S
STlM G N D
ST l M @
SYNC2
SYNC OUT
SYSCLK
SYSTEM
6-1 44
S T I M U L U S G RO U N D
G ro u nd signal from A30 Analog Sou rce to A33, A35 I n put assem b l ies
for sti m u l us s i g n a l .
ST I M U LUS ANALOG
(A30 T P8)
Signal from the A30 Analog Sou rce to the A33, A35 I n put assembl ies.
This s ignal can be the sou rce output o r the cal i b rator output.
S E R I A L DATA ACC E PT E D
(A4 T P8)
This signal is from the AS Digital Fi lter to the A6 Digital Fi lter Controller
and the A4 Local Osc i l l ator. This signal goes h igh when the d igital fi lter
accepts an in put data word. SYNC2 is asserted with i n 25 ns of the risi ng
edge of the 1 0.24 M H z clock for about 1 00 ns. The frequency of SYNC2
is determi ned by the rate of d ata acceptance. SYNC2 is used by the
l ocal osc i l l ator and d igital fi lter contro l ler to i n itiate i n putti ng serial
s i n e/cosine data i nto the d i g ital fi l ter. When the LO receives SYNC2,
it sends a com plex value to the AS D i g ital F i lter and a real va l u e to
the A1 D i g ital Sou rce.
ANA LOG P U LS E
(A1 J 1 0)
T h i s signal goes to the user output on the rear p a n e l . I t comes from
the A1 D igital Sou rce. SYNC OUT is h i gh when bu rst is on and low
when bu rst is off.
SYST EM C LOCK
(A6 W2-1 )
T h i s is a 4.91 5 M H z clock generated by the A6 D i g ital F i l ter Contro l l er.
It is u sed by the A6 Digital Fi lter Contro l ler and the AS D i g ital Fi lter
to c l ock vari o u s sequential c i rcu its.
SYST EM B U S
T h e system bus is control led by the A 2 System C P U . T h e system C P U
uses these l i nes to give commands and receive status from the fo l lowing
Digital Sou rce
Program ROM
Local Osc i l l ator
Digital Fi l ter Contro l ler
Floati ng Point Transform Processor
G lobal RAM/D i s p l ay
Fast Fou rier Processor
Keyboard
MO D E L 3562A