Tektronix 485, Instruction Manual

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Specification—485/R485 Service
DIFFERENCE Between Two Dial
Readings, Major D.T.P. Divisions
Fig. 1-3. Specified Differential Delay Accuracy vs. Size of Measure­
ment.
Jitter
Less than 0.005% (one part in 20,000) of full scale plus
0.2 ns. (Wrap-around cover must be in place.)
X -Y
Full Sensitivity
(CH 1 Vert, CH 2 Horizontal.) 5 mV/div to 5 V/div in
10 calibrated steps (1-2-5 sequence) accurate within 2%.
Gain can be recalibrated at front panel.
Y Performance
Identical to CH 1. See Vertical Deflection.
X-Axis Bandwidth
DC to 4 MHz (with 10 div reference signal).
X-Y Phase Match (Full BW and BW Limit)
Within 3° to 4 MHz.
X-Gain Match to CH 2
+15°C to +35°C: 1%
—15°C to +55°C: 3%
CRT
T E K T R O N IX CRT
4-inch rectangular tube; 8X 10 divisions (0.8 cm/div)
display area. P31 phosphor normally supplied; P11
optional without extra charge. 21 kV accelerating
potential.
Photographic Writing Speed
A t least 3 div/ns for standard P31 phosphor; at least
6 div/ns
for optional P11 phosphor (with the
TEKTRONIX C-31-R Camera and POLAROID 10,000
ASA film ).
Auto Focus
Automatically maintains beam focus for all intensity
settings. (Intensified zone and EXT Z axis are not
auto-focused).
Graticule
Internal, no parallax. Variable edge-lighting. Markings
for measurement of risetime. Graticule is dark with
illumination off.
Beam Finder
Limits display within graticule area.
External Z-Axis
Risetime 15 ns. Input R 500 T2. +0.2 V (DC to 20 MHz)
blanks trace of average intensity. +2 V (DC to 2 MHz)
blanks maximum intensity trace.
Beam Current Limit
Automatically limits the average beam current to protect
the CRT phosphor. (Limits average current to 20 pA for
sweep rates faster than 50 ms/div; 5 pA for 50 ms/div
and slower sweep rates and for X-Y. Backup system
shuts down power supply if average current reaches
approximately 30 pA.)
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