B&K 4070A Burst Mode Introduction, Burst Mode Trig Ton 10,000 mS 000,000.00 Hz Off 10.0 dBm

5.11Burst Mode

Introduction

The Burst mode generates a sinusoid burst of fixed frequency and level for a specified duration. Both continuous and triggered bursts may be generated.

In the continuous burst mode, the 4070A continuously gates the output sinusoid on and off according to the values entered in the On and Off fields.

In triggered burst mode, the output frequency is set to 0 Hz and the unit awaits a trigger condition. When a trigger condition occurs, the 4070A delays for a time specified in the Off time field and then sets the output frequency to the specified value. When the time specified in the On field has elapsed, the 4070A resets the output frequency to 0 Hz and awaits another trigger condition.

The 4070A will simultaneously accept a trigger from all of the above sources.:

1.Pressing the Trigger key

2.Applying a low-to-high transition on the Ext Trig In connector

3.Sending an ASCII "T" to the RS-232 port

NOTE: An external digital signal can be used to generate bursts by switching to Sinewave mode and using the Ext. Gating In connector to gate the output waveform on or off. The output is turned off when the input is at a logic high voltage (3V to 10V). This input can be run up to 3 MHz.

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Burst Mode	Trig		Ton:	10,000 mS
1,000,000.00 Hz		Off:	0 mS	-10.0 dBm

Figure 5.11-1: Burst mode display	4
1. Continuous / Triggered Mode

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This field selects whether the bursts will be generated on ongoing or single event basis. To select Triggered mode, press 0. To select Continuous mode, press 1. Pressing any arrow key or rotating the wheel will toggle this value.

2. Burst On Time (duration)

The burst will last for the duration specified in this field before being switched off. You may enter a value from

1 mS to 99,999 mS in 1 mS step.

3. Burst frequency

The output frequency is held at this value during the burst. You may enter from 0 Hz (DC) to 21.5 MHz in 0.01 Hz steps.

4. Burst Off Time (delay)

The burst waveform will be held at 0V for the duration in this field before the sinewave is switched on. In triggered burst mode this value may be viewed as a delay between the trigger event and when the output sinusoid is generated. You may enter a value from 0 mS to 99,999 mS in 1 mS steps.

5. Level

In this field enter the 50 ? loaded output level, from 4 mVp -p to 10 Vp -p or from -44.0 dBm to +24.0 dBm.

Offset

You can enter an offset voltage for the output waveform. For more information on refer to section 4.4.

Ext Trigger Input

In triggered burst mode this input functions as an external trigger input. A logic low-to-high transition on this input will trigger the burst. This input has an internal pull down resistor so that the input is held at a logic low when this input is left unconnected. See section 2.0 for more information.

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BK Precision 4070A User Manual Rev.2.2