background image

GVT-427B User Manual

12

4.

The  dB  and  dBm  scales  of  the  indicating  meter  are  as

stated the following:

Range setting

dB

dBm

+40
+30
+20
+10

    0

-10
-20
-30
-40
-50
-60
-70

+20
+10

0

-10
-20
-30
-40
-50
-60
-70
-80
-90

to
to
to
to
to
to
to
to
to
to
to
to

+ 41
+31
+21
+11
+  1
-  9
-19
-29
-39
-49
-59
-69

+20
+10

0

-10
-20
-30
-40
-50
-60
-70
-80
-90

to
to
to
to
to
to
to
to
to
to
to
to

+43
+33
+23
+13
+  3
-  7
-17
-27
-37
-47
-57
-67

GVT-427B User Manual

13

Specifications

This section contains a table of GVT-427B characteristics.

Table 1: Specifications

Model

Specification

GVT-427B

Channels

Two

*Indicating Meter

(105mm in scale length)

2-Pointers (Black and Red)

Scale Values

V

rms

 value of sinusoidal wave,

dB value with 1 V as 0 dBm

dBm value with 1 mW

Range Select Mode Independent / tracking control mode for each

channel range

Voltage

Measurement

12 ranges: 300 

µ

V, 1, 3, 10, 30, 100, 300 mV,

1, 3, 10, 30 and 100 V of full scale

Decibel Range

12 range: -70 to +40 dB in increments of 10

dB

Decibel Scale

-20 to +1 dB ( 0 dB = 1 V ),

-20 to +3 dBm (0 dBm = 1 mW [ 600 

])

Voltage Accuracy Within 

±

3% of full scale at 1 kHz

Summary of Contents for GVT-427B

Page 1: ...he product WARNING Warning statements identify condition or practices that could result in injury or loss of life CAUTION Caution statements identify conditions or practices that could result in damage to this product or other property The following symbols may appear in this manual or on the product DANGER High Voltage ATTENTION refer to Manual Protective Conductor Terminal Ground Earth Terminal ...

Page 2: ...loured Blue or Black The wire which is coloured Brown must be connected to the terminal marked with the letter L or P or coloured Brown or Red If in doubt consult the instructions provided with the equipment or contact the supplier This cable appliance should be protected by a suitably rated and approved HBC mains fuse refer to the rating information on the equipment and or user instructions for d...

Page 3: ...sis ground terminal is connected to the earth before inserting the power plug into the main supply 2 Maximum input voltage The voltmeter may be damaged if any input voltage exceeding the specified voltage is applied to it The specified voltage is determined by adding the peak value of the input signal and the superimposed DC voltage 300 V for the 300 µV ranges and 500 V for the 3 V to 100 V ranges...

Page 4: ...ut signals when the meter is used as a preamplifier When the range selector switch is setting at 100 mV the output voltage will be approximately equal to the input voltage However when the range selector switch is setting to the next higher or lower voltage range the amplification factor is decreased or increased by 10 dB respectively The maximum voltage of DC isolation is 12 V peak value 10 Mode ...

Page 5: ...GVT 427B User Manual 8 GVT 427B User Manual 9 ...

Page 6: ...0 log P2 P1 If the impedance is at the place where P1 and P2 are equal to each other the ratio of power could be expressed as follows dB 20 log E2 E1 20 log I2 I1 GVT 427B User Manual 11 Decibel is originally the ratio of power as explained above However the logarithm of the ratio of other values ratio of voltage or current can also been called decibel For example If the input voltage of an amplif...

Page 7: ...s section contains a table of GVT 427B characteristics Table 1 Specifications Model Specification GVT 427B Channels Two Indicating Meter 105mm in scale length 2 Pointers Black and Red Scale Values Vrms value of sinusoidal wave dB value with 1 V as 0 dBm dBm value with 1 mW Range Select Mode Independent tracking control mode for each channel range Voltage Measurement 12 ranges 300 µV 1 3 10 30 100 ...

Page 8: ...ull scale without load AC Frequency Response 10 Hz to 1 MHz 3 reference 1 kHz without load Stability against Line Voltage Fluctuation Indication change with respect to line voltage fluctuation of 10 is within 0 5 of full scale GVT 427B User Manual 15 AC Power Requirement 115 230 Vac 50 60 Hz Table 1 Specifications Cont AC Power Consumption 8 5VA or 5 0 Watts Maximum Fuse Replacement for 115 Vac se...

Page 9: ...er operational difficulties with your GVT 427B contact your Good Will representative for assistance WARNING To avoid electrical shock the power cord protective grounding conductor must be connected to ground WARNING To continued fire protection Replace fuse with the specified type and rating and disconnect the power cord before replacing fuse GVT 427B User Manual 17 Interchangeable Parts Interchan...

Reviews: