109: Difference between revisions

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The 109's operating principle is that of a
The 109's operating principle is that of a
[http://en.wikipedia.org/wiki/Pulse_forming_network#Transmission_line_PFNs charged transmission line pulse generator]
[http://en.wikipedia.org/wiki/Pulse_forming_network#Transmission_line_PFNs charged transmission line pulse generator]
with a mechanical reed switch and external 50 Ω transmission line/lines attached through two GR-874 50 Ω connectors.
with a mechanical reed switch and external 50 Ω; transmission line/lines attached through two GR-874 50 Ω connectors.
The length of the external cables determines the impulse width.
The length of the external cables determines the impulse width.
Using two transmission lines of non-equal length, alternating pulses having different width can be produced. 
Alternatively, an R-C network can be used to create pulses with R-C decay characteristic but longer duration.


The pulse-generating switch in the 109 is a mechanical [[mercury switch]], which limits pulse frequency to about 600 Hz.
The pulse-generating switch in the 109 is a mechanical [[mercury switch]], which limits pulse frequency to about 600 Hz.
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The internal voltage source is adjustable from 0 to 50 V in three ranges (0.5 V, 5 V, 50 V), either positive or negative.   
The internal voltage source is adjustable from 0 to 50 V in three ranges (0.5 V, 5 V, 50 V), either positive or negative.   
Using an external voltage source, pulses up to 300 V are possible.
Using external voltage sources, pulses up to 300 V of either polarity are possible, including alternating positive/negative pulses.


==Repair issues==
==Repair issues==
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==Links==
==Links==


* [http://cds.linear.com/docs/en/application-note/an120f.pdf Jim Williams, Linear Technology Application Note 120, "1ppm Settling Time Measurement for a Monolithic 18-Bit DAC"] - see Appendix H (p.30)
* [http://cds.linear.com/docs/en/application-note/an120f.pdf Jim Williams, Linear Technology Application Note 120, "1 ppm Settling Time Measurement for a Monolithic 18-Bit DAC"] - see Appendix H (p.30)
* [http://w140.com/slac-tn-71-027.pdf Report comparing RG-58 with RG-174 using Tek 109 and Tek 661 (PDF)]
* [http://w140.com/slac-tn-71-027.pdf Report comparing RG-58 with RG-174 using Tek 109 and Tek 661 (PDF)]
* [http://www.amplifier.cd/Test_Equipment/Tektronix/Tektronix_other/109.html Tek 109 page @ amplifier.cd]
* [http://www.amplifier.cd/Test_Equipment/Tektronix/Tektronix_other/109.html Tek 109 page @ amplifier.cd]
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==Pictures==
==Pictures==
<gallery>
<gallery>
File:109_front.jpg | Front view
File:109_front.jpg         | Front view
File:109_right.jpg | Right internal
File:109_right.jpg         | Right internal
File:109_left.jpg   | Left internal
File:109_left.jpg         | Left internal
File:109_back.jpg | Rear view Connector not original
File:109_back.jpg         | Rear view Connector not original
File:109_impulse.jpg | flying spot caught with 7904, S6, 7T11, 7M11. 2.5&nbsp;V<sub>pk</sub>, T<sub>r</sub>=240&nbsp;ps
File:109_impulse.jpg       | flying spot caught with 7904, S6, 7T11, 7M11. 2.5 V<sub>pk</sub>, T<sub>r</sub>=240 ps
File:Tek 109 schematic.png | schematic
File:Tek 109 schematic.png | schematic
File:Tek-017-067.jpg      | 017-067 Charge network for 109
File:017-067.jpg          | 017-067 Charge network for 109 (description)
</gallery>
</gallery>



Revision as of 04:37, 30 June 2015

The Tektronix Type 109 is a pulse generator introduced in 1962. It uses a GR-874 50 Ω output connector and has a specified rise time of 250 ps.

Key Specifications

Rise time 250 ps
Pulse frequency 550 to 720 Hz
Pulse length 0.5 ns to 100 ns with a single charge line between the two charge line connectors, or up to 300 ns at half pulse rate with one open-ended charge line (other connector grounded)
Pulse amplitude Internal supply: 0 to 50 V variable in three ranges (0.5 V, 5 V, 50 V), positive or negative, or external up to ± 300 V

Manuals

Internals

The 109's operating principle is that of a charged transmission line pulse generator with a mechanical reed switch and external 50 Ω; transmission line/lines attached through two GR-874 50 Ω connectors. The length of the external cables determines the impulse width. Using two transmission lines of non-equal length, alternating pulses having different width can be produced. Alternatively, an R-C network can be used to create pulses with R-C decay characteristic but longer duration.

The pulse-generating switch in the 109 is a mechanical mercury switch, which limits pulse frequency to about 600 Hz. Moreover, this switch has a relatively short life time (200 hours) — if the operator forgets to shut the 109 down over the weekend and some holidays, the reed switch will need replacement.

The internal voltage source is adjustable from 0 to 50 V in three ranges (0.5 V, 5 V, 50 V), either positive or negative. Using external voltage sources, pulses up to 300 V of either polarity are possible, including alternating positive/negative pulses.

Repair issues

Be aware during servicing that the thermal breaker is on full mains and has no protection cover!

Links

Pictures