HP 8340b - Mhz Frequency Standard

A34
REFERENCE
LOOP
-
M/N
LOOP MOTHERBOARD
This
assembly
is
attached
to
a
metal
casting
that
forms
an
enclosed housing for
the
following
refer¬
ence
—
M/N
loop assemblies:
•
A29
reference phase
detector
assembly
•
A30100
MHz
VCXO
assembly
•
A31
M/N
phase detector
assembly
•
ASS
M/N
output assembly
Each
of
these
assemblies
has
a
sheet
metal
plate
attached
to
it,
that
completes
the
reference
—
M/N
enclosure.
The
enclosure
provides
RFI
(radio
frequency
interference)
shielding.
A51
10
MHz
FREQUENCY STANDARD
This is
a
self-contained,
oven-stabilized,
precision
reference oscillator.
The
output
of
the
A51
fre¬
quency
standard
is
sent
to
the
A29
reference
phase
detector
assembly
through
the
rear
panel
jumper.
HP
8340B/41B
Reference
Loop Theory
of
Operation B-3