Tektronix 2445A Service Manual page 11

Specification-2445A/2455A Service
Table 1-1 (cont)
Characteristics
Performance Requirements
AC Coupled, Lower -3 dB Frequency 10 Hz or less. 8
With Standard Accessory Probe
1 Hz or less.
Step Response Rise Time Calculated from Tr=0.35/BW. (a)
2455A
<= 1.4 ns.
2445A <= 2.33 ns.
Channel Isolation
>= 100:1 attenuation of deselected channel at 100 MHz; >= 50:1 at
350 MHz, for an eight-division input signal from 2 mV per division
to 500 mv per division, with equal VOL TS/DIV settings on both
channels.
Displayed Channel 2 Signal Delay with Respect to Adjustable through a range of at least -500 ps to +500 ps.
8
Channel 1 Signal
Input R and C (1 þÿM©)
Resistance
1 þÿM© ±0.5%.
8
Capacitance 15 pF ±2 pF.
8
Maximum Input Voltage
DC, AC, or GND Coupled 400 V (de + peak ac).
800 V p-p ac at 10 kHz or less.
8
Input R (50 þÿ©)
Resistance 50 þÿ© ±1%. 8
VSWR
<=1 :3:1 for de to Nominal Bandwidth.
Maximum Input Voltage 5 V rms, averaged for 1 second; ± 50 V
peak.
Cascaded Operation Channel 2 Vertical Signal Output into Channel 1 input; DC coupled
using a 50 þÿ© RG-58C/U coaxial cable, terminated in 50 þÿ © a t the
Channel 1 input. Channel 1 and Channel 2 VOL TS/DIV set at 2 mV
and Bandwidth Limit On.
Deflection Factor 400 µV per division ± 10%.
CMRR (ADD Mode with Channel 2 inverted) At least 20: 1 at 50 MHz for common-mode signals of eight
divisions or less, with VAR VOL TS/DIV control adjusted for best
CMRR at 50 kHz, at any VOL TS/DIV setting.
•Performance requirement not checked In manual.
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