Velleman DVM13MFC2U User Manual

DVM13MFC2U

2.4GHz HIGH-RESOLUTION FREQUENCY COUNTER
CONTADOR DE FRECUENCIA DE ALTA RESOLUCIÓN 2.4GHz
COMPTEUR DE FRÉQUENCE HAUTE RÉSOLUTION 2.4GHz

USER MANUAL
MANUAL DEL USUARIO
NOTICE D’EMPLOI

DVM13MFC2U VELLEMAN

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DVM13MFC2U – 2.4GHz HIGH-RESOLUTION FREQUENCY COUNTER

1. Introduction & Features

Thank you for buying the DVM13MFC2U! Please read the manual thoroughly before bringing this device into service. If the device was damaged
in transit, don't install or use it and contact your dealer.
The DVM13MFC2U is a high-resolution, multifunction intelligent frequency counter based on a microprocessor. The features include:
frequency, period measuring, 3-step function selection, working state, unit and 8-digit LED display.

2. Description

1. port channel A 10. CONFIRM key

2. port channel B 11. FUNCTION key

3. frequency indication LED 12. ATT key

4. period indication LED 13. AC/DC COUPLING key

5. LED display 14. GATE TIME knob

6. kHz/s indication LED 15. POWER switch

7. MHz/ms indication LED 16. 220V/110V switch

8. RESET key 17. power jack and fuse

9. PERIOD key

3. The Keys

Make sure to connect your DVM13MFC2U to an AC 220V/110V (± 10%) mains socket. Maximum consumption is 5W. Switch on your device
20 minutes before measuring. This preheats the unit and the crystal oscillator to ensure accurate readings and stability.

FUNCTION key (3 steps)

Step 1: 50MHz ~ 2.4GHz range, input from channel B, measurement unit indication in MHz/ms.
Step 2: 2MHz ~ 50MHz range, input from channel A, measurement unit indication in MHz/ms.
Step 3: 0.01Hz ~ 2MHz range, input from channel A, measurement unit indication in KHz/s.

PERIOD key

Press this key to enter the period measurement mode.

CONFIRM key

Press this key, the instrument will start working according the preset mode.

AC/DC COUPLING key

Position this button in the down position for DC measurements. Position this button in the up position for AC measurements.

RESET key

Press this key to reset your DVM13MFC2U.

ATT key

Position this button in the down position for a measurement attenuated by 20dB. Position this button in the up position for a non­attenuated measurement.

4. Operation

Connect the power cord to a power outlet (AC 220V/110V, 50Hz or 60Hz) and switch on your DVM13MFC2U. Allow the unit to warm up for
20 minutes.

Make sure to match the voltage from the local mains with the voltage on your DVM13MFC2U.
Check the 220V/110V switch at the back of the device.

DVM13MFC2U VELLEMAN

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Frequency Measurement

1. Select channel A or channel B (depending on the range being measured) and connect it to the signal source by means of the cable.

2. Press the AC/DC COUPLING key if the frequency of the signal to be measured is less than 100Hz.

3. If the input signal is high, press the ATT key to ensure that the DVM13MFC2U will measure an attenuated signal.

4. When the FUNCTION key is pressed, the last digit display value is the current selection step.

The frequency measurement has only 3 steps.

5. Complete steps 1 to 3 and press the CONFIRM key. The DVM13MFC2U displays the measurement results.

6. Adjust the gate time.

7. When measuring a 100Hz signal, the device will automatically start measuring the period and display the measuring results.

Period Measurement

Press the PERIOD key. The device will start measuring the period and display the test results.

5. Examples

• Connect the DVM13MFC2U to the mains (110V/220V AC).

• Switch on the device with the ON button and preheat it for 20 minutes.

• Connect the test cable with the input port on the front panel. Select channel A or B according to the frequency range.

• Select the proper function and gate time. The shorter the gate time, the faster the frequency measurement but the lower the resolution.

The longer the gate time, the slower the frequency measurement but the higher the resolution.

• Press PERIOD to measure the period. Confirm by pressing the CONFIRM key. The device starts measuring.

Example 1: Measuring an analogue handset

Connect the test cable with the input from channel B and set the FUNCTION key to the 1-step position. Select the gate time (adjust manually
from 100 msec to 10 sec). The LED display will read:

Example 2: Measuring a 30Mhz intercom emission frequency

Set the FUNCTION to the 2-step position and select the gate time (adjust manually from 100 msec to 10 sec). The LED display will read:

Example 3: Measuring a self-oscillating frequency (e.g. from a telephone, intercom etc.)

Set the FUNCTION key to the 2-step position. Connect one end of a cable with 5pF capacitance to the red clamp; use the other end to
measure the frequency by touching the contact point.

6. Warnings

• When measuring a high-voltage or strong RF signal, make sure that the cables are in series and have a large capacitance to avoid

damage.

• Press the RESET button once to reset the device or turn off the device in case the device is not working appropriately.

• When there is no input signal, the display may not necessarily read “0”. This is absolutely normal and does not affect the measurements

or the accuracy.

• Do not expose the device to extreme temperatures, humidity, dirt, dust etc. Do not open the device to avoid lethal electroshocks.

• A strong interference will reduce the sensitivity when measuring.

1-step

900MHz

2-step

30MHz