3B4
The Tektronix Type 3B4 is a timebase plug-in for 560-series scopes, introduced in 1964.
It was intended primarily for use with the 561A, but works fine in other 560-series scopes. The 3B4 is unusual in having an explicit "FREE RUN" mode.
In the triggered modes, the tunnel diode-based triggering is rated to work to 20 MHz. The vertical bandwidth of typical 560-series (non-sampling) scopes is about 10 MHz, so 20 MHz is adequate.
Triggering is done with a TD3A 4.7 mA tunnel diode. The trigger input is amplified and buffered by a 6DJ8-based differential amplifier driving a common-emitter 2N964 germanium PNP transistor whose collector current switches the tunnel diode.
The 283 Real Time adapter enables real-time sweeps with a 3B4.
Key Specifications
- please add
Links
Pictures
front view
left side view
right side view
top view
Some Parts Used in the 3B4
| Page | Class | Description | Used in |
|---|---|---|---|
| 6DJ8 | Vacuum Tube (Dual Triode) | dual triode | 80 • 132 • 161 • 310A • 316 • 317 • 3A75 • 502 • 502A • 503 • 504 • 515 • 516 • 519 • 526 • 529 • RM529 • 533 • 535 • 536 • 543 • 544 • 545 • 545A • 545B • 546 • 547 • 549 • 555 • 556 • 565 • 581 • 581A • 585 • 585A • 661 • 2A60 • 63 • 2A63 • 3A7 • 3A8 • 1121 • 1A4 • 67 • 81 • 82 • 86 • 3B1 • 3B4 • 1S1 • B • O • W • Z • Telequipment S32A • Telequipment D52 • Telequipment TD51 • Telequipment S52 • Telequipment S51 • Telequipment Type A |
| 7119 | Vacuum Tube (Dual Triode) | dual triode | 067-0532-00 • 191 • 3A3 • 3B4 • 3B5 • 516 • 545B • 549 • 661 |