From TekWiki
Jump to navigation Jump to search
Tektronix PG508
50 MHz pulse generator
Tektronix PG508

Produced from 1976 to 1993

(All manuals in PDF format unless noted otherwise)
Manuals – Specifications – Links – Pictures

The Tektronix PG508 is a 50 MHz pulse generator plug-in for the TM500 system.

It was designed by Fred Beckett, Dennis Feucht, Tom Hill, and Gary Kersey.

Pulses can be triggered by an external input, a manual trigger button, or an internal period generator (optionally gated by the trigger input). The trigger signal can be undelayed, delayed by a selectable time, or both (in which case double pulses are generated). The pulse duration, leading and trailing edge transition times, high- and low-level amplitude can be controlled independently.

Period, delay, duration, and transition time switches each feature a custom position where a user-supplied internal capacitor determines the timing.

Key Specifications

Period external, or internal <20 ns to >200 ms in 7 decade steps plus variable; ≥200 ms possible in custom range
Jitter <0.1% +50 ps
Delay Time <10 ns to >100 ms in 7 decade steps plus custom position and variable control; ≥100 ms possible in custom range
Pulse Duration square, or <10 ns to >100 ms in 7 decade steps plus custom position and variable control; ≥100 ms possible in custom range
Transition time Ranges 5 ns to 500 μs in decade steps plus custom position; separate  ×1 to ×100 variable controls for leading and trailing edge (5 ns to 50 ms effective)
Output level High and low levels adjustable independently in −20 V to +20 V range, limited to max. 20 Vp-p / min. 1 Vp-p (open circuit), 50 Ω source impedance (−10 V to +10 V, 0.5 to 10 Vp-p into 50 Ω)
Trigger/Gate input Sensitivity 80 mVp-p to ≥10 MHz, 250 mVp-p to ≥50 MHz at 50 Ω impedance, max. ±5 Vpeak; 1 MΩ // 20 pF optionally selectable (internal switch), max. ±20 Vpeak

Rear Interface

(on right-hand plug-in slot as viewed from front)

Connector Pin Description
Signal Return
27B 28B Trig output (complement polarity installed; for normal polarity, front panel input requires optional cable and front output disconnection) [note error on manual page 1-12; table 1-13 is correct]
24B 25B Trig input (with optional cable, front panel input must be disconnected)
25A 26A Amplitude Monitor (from output via 27 kΩ)
22A External Low Level Control Input (requires internal jumper and trim)
22B External High Level Control Input (requires internal jumper and trim)

Custom connection solder pads are available on the left plug-in slot, which is otherwise used only for the associated pass transistors in the mainframe.




Custom ICs used in the PG508

Page Class Manufacturer Model Part nos Description Designers Used in
155-0078-00 Monolithic integrated circuit Tektronix M084 155-0078-xx 155-0273-00 155-0274-00 broadband vertical amplifier John Addis 464 465 466 468 475 475A 475M 485 7834 7844 7854 7904 R7903 R7912 7912AD 7912HB 7104 7A16A 7A16P 7A24 7A26 7A42 067-0587-01 067-0680-00 AM503 PG502 PG508 DC510 DC5010 FG5010