Tektronix 1A5 Instruction Manual page 25

Method Advantages
Permits
5. Tap into termi ­
nated coaxial sys ­ go to normal load.
tem. (BNC T at 1 A5 DC or AC coupling
without coaxial at ­
input.)
tenuators.
Full sensitivity.
6. 1 × , 1MΩ
Total
Probe.
Oscilloscope band ­
width.
Reduced resistive
7. 10 × probe.
and capacitive
loading; nearly full
bandwidth of 1A5.
100 × , 9.1 MΩ
probe.
1000 × , 100 MΩ
probe.
8. 500 Ω and 5 kΩ Reduced
tive loading to
probes. (Must be
about 0.7 pF.
terminated in 50 Ω
at 1A5 input.) Bandwidth that of
1A5.
9. Current trans ­ Current transform ­
former. Terminated er can be perma ­
in 50 Ω at 1A5. nent part of test
circuit.
2.2 pF to test cir ­
cuit chassis. Meas ­
ure signal cuurrent
in transistor cir ­
cuits:
CT-1 — 20 A peak.
CT-2 — 100 A peak.
10. P6019 or P6020 Measure signal
Current Probe and currents.
Type 134 Amplifi ­ rent saturation rat ­
er.
ing: 15 A peak to
peak.
Type P6023 Probe Adjustment Procedure
The following equipment is recommended for this proce ­
dure:
Oscilloscope to be used with the Type 1 A5.
TABLE 2-3 (cont)
Passive Signal Coupling Methods
Limitations
signal to 20-pF load at tap
point.
High capacitance
Type 1A5- of cable.
× 0.1 sensitivity.
× 0.01 sensitivity.
× 0.001 sensitivity.
capaci ­ Resistive loading.
× 0.1 or × 0.01
sensitivity. May
need blocking ca ­
pacitor to prevent
DC loading or dam ­
age to termination.
Limited low-fre ­
quency response
when AC coupled.
See Fig. 2-13.
RMS current rating:
CT-1 — 0.5 A
CT-2 — 2.5 A
Less than Sensitivity:
CT-1 — 5 mV/mA.
CT-2 — 1 mV/mA.
Low frequency lim ­
AC cur ­ it: — 30 Hz. Basic
deflection factor:
50 mV/mA.
Operating Instructions — Type 1A5
Accessories
Required Source Loading
BNC T and BNC 1 MΩ
connectors on sig ­ at tap point.
nal cables.
P6011 and P6028 1 MΩ and ≈ 60 pF.
are 1 × probes. 1 MΩ and ≈ 28 pF.
P6006, P6008, P6006: ≈ 7 pF ,
P6010 and P6023 10 MΩ.
P6008: ≈ 7.5pF,
are 10 × probes.
10 MΩ.
P6010: ≈ 10 pF,
10 MΩ
P6023: ≈ 12 pF,
8 MΩ
P6007: 100 × P6007: ≈ 2pF,
10 MΩ.
P6015: 1000 × P6015: ≈ 2.7pF,
100 MΩ.
P6034: 10 × . P6034: 500 Ω,
P6035: 5 kΩ, 0.6 pF. 0.7 pF.
CT-1: Insertion; 1 Ω
CT-1 : coaxial cable,
adapter and BNC paralleled by
termination. about 5 µH. Up
to 1.5 pF.
CT-2: Additional
CT-2: Insertion;
coaxial cable for
0.04 Ω paralleled
either transform ­
er as necessary. by about 5 µH. Up
to 2.2 pF.
None. Insertion Z with
step function
plied: 0.04 Ω after
0.1 µs.
Type 1A5 Differential Amplifier plug-in unit.
Type P6023 Probe. (Two required for differential oper ­
ation.)
BNC binding post adapter.
0033-00.
Precautions
Reflection from 20
and 20 pF
pF input.
High capacitance
loading.
Check probe fre ­
quency compensa ­
tion. Use square
wave frequency
less than 5 kHz,
preferably 1 kHz.
DC and AC load ­
ing.
Voltage rating of
probe.
Not a quick-con ­
nect device.
CT-1: Low-fre ­
quency limit about
75 kHz.
CT-2: Low-fre ­
quency limit
about 1.2 kHz, and
is 1 /5th as sensi ­
tive as the CT-1 .
Avoid scratching
probe current trans ­
ap ­
former core to pre ­
serve low-frequen ­
cy response.
Tektronix Part No. 103-
2-17