7B71
The Tektronix 7B71 Delaying Time Base is a 200 MHz time base plug-in for 7000-series scopes. It was designed by Murlan Kaufman.
The 7B71 contains a delay function to control a "B" horizontal plug-in in four-slot mainframes, typically a model 7B70. It has no provision for X-Y mode.
The 7B70/7B71 were primarily intended for the 7704 mainframe. They were superseded by the 7B85/7B80 pair (400 MHz) in 1976, which increased the frequency range to 400 MHz and added digital read-out of the delay time.
Key Specifications
| Sweep | 5 s/Div to 20 ns/Div in 1−2−5 sequence, ×10 magnifier down to 2 ns/Div, variable down to 12.5 s/Div |
|---|---|
| Excluded portions of sweep | None in 7700-series, first 50 ns with magnifier |
| Trigger sensitivity | 0.3 Div (int) or 75 mV (ext) up to 20 MHz, 1.5 Div or 375 mV from 20 MHz to 200 MHz |
| Trigger coupling | DC, AC (>30 Hz), AC HF REJ (30 Hz to 50 kHz), AC LF REJ (>30 kHz) |
| Trigger input | 1 MΩ // 20 pF, max. 500 V DC+peak AC |
| Jitter | less than 1 ns at 150 MHz |
| Trigger Modes | Peak-Peak Auto, Auto, Norm, Single Sweep |
| Variable time delay accuracy | 1% (0.5 s/Div to 1 μs/Div) |
| Variable time delay multiplier Linearity | within 0.2% |
Links
- Troubleshooting the 7B70 and 7B71 timebases. Tekscope Vol.6 No.4 Sept/Oct 1974
- Tek 7B71 @ barrytech.com (waybackarchive)
- Tek 7B71 @ amplifier.cd
- Zenwizard Studios - Tektronix 7B71 Repair and Partial Alignment
Documents referencing 7B71
| Document | Class | Title | Authors | Year | Links |
|---|---|---|---|---|---|
| Tekscope 1969 V1 N5 Oct 1969.pdf | Article | Introducing the New Generation | 1969 | 7000-series scopes • 7504 • 7704 • 7A11 • 7A12 • 7A13 • 7A14 • 7A16 • 7A22 • 7S11 • 7M11 • 7B50 • 7B51 • 7B70 • 7B71 | |
| Tekscope 1969 V1 N6 Dec 1969.pdf | Article | A New Logic for Oscilloscope Displays | 1969 | 7000-series scopes • 7A11 • 7A12 • 7A13 • 7A14 • 7A16 • 7A22 • 7B50 • 7B51 • 7B70 • 7B71 • 7S11 • 7T11 • 7504 • 7704 | |
| 7000 series brochure March 1973.pdf | Brochure | 7000 series brochure, March 1973 | 1973 | 7A11 • 7A12 • 7A13 • 7A14 • 7A15A • 7A16A • 7A17 • 7A18 • 7A19 • 7A21N • 7A22 • 7B50 • 7B53A • 7B70 • 7B71 • 7B92 • 7CT1N • 7D11 • 7D13 • 7D14 • 7D15 • 7M11 • 7L12 • 7S11 • 7S12 • 7T11 • 7704A • R7704 • 7904 • R7903 • 7603 • R7603 • 7403N • R7403N • 7313 • R7313 • 7613 • R7613 • 7623 • R7623 • P7001 | |
| Tekscope 1974 V6 N4.pdf | Article | Troubleshooting the 7B70 and 7B71 Time Bases | Jim Lawe | 1974 | 7B70 • 7B71 |
Patents that may apply to 7B71
Internals
The 7B71 contains five 148-0034-00 miniature relays and one 148-0035-00. It also contains one 152-0154-00 and two 152-0125-00 tunnel diodes.
Pictures
7B71 MOD515C Plugin
The 7B71 Mod 515C adds the ability to remotely operate the triggering level, the position & delay time, the magnifier setting and the trigger-modes. The modified 7B71 timebase can be configured as a delaying or as a delayed timebase. See WP1000AF for further details
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Front view of a 7B71 plugin with MOD515C
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Left side
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Right side
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Top side
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Closeup of serial number and MOD515C sticker
