7A29
Template:Plugin Sidebar 2 The Tektronix 7A29 is a 1 GHz single-channel vertical plug-in for 7000-series scopes. It is primarily intended for the 7103 and 7104. Like with the 7A19, a variable signal delay was available as an option.
There is also a 7A29P, which has digitally programmable gain, intended for the 7000 series digitizers and the 7854 only.
The 7F10 uses the 7A29's amplifier board after the optical/electrical converter.
Key Specifications
| Bandwidth | 1 GHz (in 7104) |
|---|---|
| Input impedance | 50±1 Ω, VSWR <1.2:1 from DC to 1 GHz (10 mV/Div: 1.4:1, Opt.4: 1.5:1) |
| Max. input | max. 10 VRMS or 1 Ws pulses not exceeding 50 V; max. 100 V additional DC component in AC mode |
| Deflection | 10 mV/div to 1 V/div, 1-2-5, ±2%; variable 2.5:1 |
| Channels | Single channel |
| Recommended probes | P6056 (×10), P6057 (×100) |
| Options | Option 4: variable delay (1 ns) |
Internals
The 7A29 employs a number of Tek-made custom Hypcon-packaged hybrids, the 155-0180-00 fast input protection, 155-0181-00 input amplifier and 155-0175-00 trigger amplifier (2 ×).
It uses a "feed-beside" scheme implemented with standard low-frequency operational amplifiers to compensate for low-frequency anomalies in the frequency response that are attributed to transistor heating.
The input connector is a special Tek-made part that is exactly 50 Ω. Typical BNC connectors are around 52 Ω.
Links
- Tektronix 7A29 teardown - nice detailed pictures of attenuator internals
- Tek 7A29P @ amplifier.cd including internal pictures
Pictures
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7A29 (no opt.) front
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7A29 Opt.4 front
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7A29P
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photo of 7A29 from manual (normal and option 4 units)
Internal
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7A29, left side
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7A29 Opt.4, left view (variable delay line enclosure above PCB)
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7A29, right side
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7A29 input protection relay
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7A29 input protection relay lever
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7A29 backplane connector (stripline signal path)
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7A29 amplifiers
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7A29, right side, rear
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7A29, right side, front
Schematics
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input amplifier schematic
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output amplifier schematic
