3B2
The Tektronix Type 3B2 is a delaying timebase introduced in 1963 for 560-series scopes except the 560 and 565. It can trigger on signals up to 30 MHz (limited to 500 kHz when used with low frequency vertical plugins like the 3A2).
The 3B2 has a 6CW4 Nuvistor triode cathode-follower buffer amplifier at the trigger input, followed by a differential trigger amplifier made of a pair of PNP transistors, with a 2 mA tunnel diode acting as the actual trigger.
The 3B2 has a 1 MHz crystal oscillator and a counter made of discrete transistors. It generates output pulses that enable it to communicate with a digital unit such as the 6R1 or 6R1A.
The 3B2 uses a 6AL5 tube as the disconnect diode for the sweep.
Key Specifications
| Trigger Frequency | DC to 30 MHz |
|---|---|
| Sweep Speeds | 1 sec/div to 2 μs/div |
| Sweep Types | Normal and Delayed |
Pictures
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3B2 Front
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3B2 Right
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3B2 Left
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3B2 Right
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3B2 Logic Boards
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3B2 Bottom
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3B2 Top
Components
Some Parts Used in the 3B2
| Part | Part Number(s) | Class | Description | Used in |
|---|---|---|---|---|
| 12AL5 | 154-0038-00 | Vacuum Tube (Double Diode) | high-perveance dual diode | 3A2 • 3B2 • 545 • 545A • 549 • N |
| 1N3714 | 152-0081-00 | Discrete component | 2.2 mA, 25 pF germanium tunnel diode | 546 • 547 • 556 • 21A • 22A • 3B1 • 3B2 • 3B3 • 422 • 491 • 283 |
| 6AL5 | 154-016 • 154-0016-00 • 154-0038-00 | Vacuum Tube (Dual Diode) | high-perveance dual diode | 163 • 181 • 190 • 1M1 • 310 • 310A • 315 • 316 • 317 • 3B1 • 3B1S • 3B2 • 3B3 • 3B5 • 502 • 502A • 503 • 511 • 511A • 512 • 516 • 517 • 517A • 524 • 526 • 535 • 535A • 545 • 545A • 549 • 551 • 565 • 570 • 581 • 581A • 585 • 585A • C • T • Telequipment S52 |
| 6BL8 | 154-0278-00 | Vacuum Tube (Triode/Pentode) | triode-pentode combo | 67 • 2B67 • 3B1 • 3B1S • 3B2 • 3B3 • 3B4 • 503 • 504 • 506 • 516 • 549 • 561 • 561A • 561S • 564 • 565 • 567 • Telequipment D52 • Telequipment S31 • Telequipment S32 • Telequipment S32A • Telequipment S51 • Telequipment S52 |
| 6C4 | 154-029 • 154-0029-00 | Vacuum Tube (Triode) | VHF triode | 190 • 3B2 • 507 • 511 • 511A • 517 • 517A • Chemtrix 205 |
| 6CW4 | 154-0323-00 | Vacuum Tube (Triode) | Nuvistor triode | 1A7 • 3A8 • 3B2 • 3S76 • 6R1 • 565 • S-311 |
| 6DJ8 | 154-0187-00 • 154-0305-00 | Vacuum Tube (Dual Triode) | dual triode | 132 • 161 • 310A • 316 • 317 • 502 • 502A • 503 • 504 • 506 • 515 • 516 • 519 • 526 • 529 • RM529 • 533 • 535 • 536 • 543 • 544 • 545 • 545A • 545B • 546 • 547 • 549 • 555 • 556 • 561A • 561S • 564 • 565 • 567 • 581 • 581A • 585 • 585A • 661 • 1A4 • 1S1 • 60 • 2A60 • 63 • 2A63 • 67 • 2B67 • 3A1 • 3A1S • 3A2 • 3A3 • 3A6 • 3A7 • 72 • 3A72 • 75 • 3A75 • 4S2 • 51 • 3B1 • 3B1S • 3B2 • 3B3 • 3B4 • 3M1 • 3S76 • 3T77 • 3T77A • 9A1 • 9A2 • 1121 • 80 • 81 • 82 • 86 • B • O • W • Z • Telequipment S32A • Telequipment D52 • S-311 • Telequipment TD51 • Telequipment S52 • Telequipment S51 • Telequipment Type A • TU-4 |
| TD714 | 152-0402-00 | Discrete component | 2.2 mA, 25 pF tunnel diode | 1401 • 1401A • 283 • R283 • 3B2 • 3B3 • 422 • 491 • 546 • RM546 • 547 • RM547 • 556 • RM556 • SPG11 • SPG12 |
| ZZ1000 | 154-370 • 154-0370-00 | Gas Discharge Tube (Voltage regulator) | 81 V voltage reference | 129 • 3B1 • 3B1S • 3B2 • 3B3 • 3S76 • 422 • S-311 |