B&K 4071 user manual Voltage Controlled Oscillator VCO Mode, Start End 1,000,000.00 Hz 10.0 dBm

5.26 Voltage Controlled Oscillator (VCO) Mode

Introduction

The Voltage Controlled Oscillator mode generates signal, where frequency could be vary between two specified values using ext ernally supplied -5.0V/+5.0V voltage. The control input bandwidth is DC to 35 KHz. Start, End frequencies, output level and DC offset values could be manually entered from the front panel keypad in this mode. External signal gating options is available in this mode. External Sweep (VCO) mode could be entered by pressing “Mode”> “Sweep” >”2” key at any time.

VCO Mode Parameters

The Voltage Controlled Oscillator mode has the following front panel display:

	VCO	Start:	0 Hz
	End: 1,000,000.00 Hz		-10.0 dBm
2

Figure 5.26-1: VCO mode display

1. Start Frequency

1

3

This is the output frequency when -5.0V is applied to the External Modulation In connector (rear panel). You may enter from 0 Hz (DC) to 31.5 MHz in 0.01 Hz steps.

NOTE: You are not allowed to enter a start frequency that is greater than the end frequency.

2. End Frequency

This is the output frequency when +5.0V is applied to the External Modulation In connector (rear panel). You may enter from 0 Hz (DC) to 31.5 MHz in 0.01 Hz steps.

NOTE: You are not allowed to enter end frequency that is less than the start frequency.

3. Level

In this field enter the output level, from 4 mVp -p to 5 Vp -p in 1 mV steps or from -44.0 dBm to +18.0 dBm in 0.1 dBm steps.

NOTE: The level specified is a 50O loaded level. This is the level of the signal will appear across a 50O load connected to the SIG Out connector. Into an open circuit, the output swing will be twice the value entered.

Offset

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

External Modulation In

Apply the control voltage to this connector. For this mode, the input signal may be in the -5.0V to +5.0V range. Levels outside this range will be clipped by limiting circuitry.

*** Caution***

Levels outside ±25V may damage the 4071.

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BK Precision 4071 User Manual Rev.2.2