Vremya-ch VCH-315M, Руководство по эксплуатации

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2
1
2
1
2
1
, ,
c x y
  
– Allan variance of "

fx" and "

fy" input signals and the
measuring channel CHANNEL 1.
Figure 5
Instability of the measuring channel CHANNEL 1 –
1 1 1
, ,
c c
N
c
y
 
("noise floor")
can be calculated if the same signal is connected to both "

fx" and "

fy" inputs.
The "

fy" input signal instability estimate is biased and includes the instability
( systematic error ) of the reference signal and the measurement channel. When using
this method you need to be sure that instability of the reference signal and
measurement channel is much less than that of measured signal.
Signal
Source
Y
1
RS-232 interface
cable
(included
with
the
instrument
set
composition)
UTP cable
8P8C plug
Personal Computer
Multichannel frequency comparator VCH-315M
 fy  fx
CHANNEL 1
RS-232
LAN
~220 V 50 Hz 40 V·A 
22...30 V, 35 W
POWER SUPPLY PROCESSOR
USB
Power connecting cord
AC power connecting cord
(connector 2PMT14КПН4Г1В1)
USB interface cable
 fy  fx
CHANNEL 2 CHANNEL 3 CHANNEL 4 CHANNEL 8
 fy  fx
 fy  fx  fy  fx
Connecting
cables, 50 Ohm
Connecting
cables, 50 Ohm
Signal
Source
X
1
Signal
Source
Y
2
Signal
Source
X
2
Signal
Source
Y
3
Signal
Source
X
3
Signal
Source
Y
4
Signal
Source
X
4
Signal
Source
X
8
Signal
Source
Y
8