Faced with an oscilloscope, an uninformed person has many questions why there are so many switches and control knobs on it. Everything is pretty simple and logical. Now we will describe, using the example of the C1-49 electron-beam measuring device, which is widespread in the circles of radio amateurs, how to use an oscilloscope.
Content:
- Briefly about management
- User manual
Briefly about management
The C1-49 model looks like in the photo:
The toggle switch for switching on the device is located on the right side with the inscription “Network», After moving the toggle switch to the on position, the red light indicator above it should light up.
Handle "Focus»Changes the beam thickness - since the device is not equipped with a temperature compensation unit, and the diameter changes as the oscilloscope heats up.
Regulator with the inscription "Brightness»Adjusts the brightness of the dot on the screen, can be individually adjusted to the working environment.
«Scale illumination», Again an individual approach to the illumination of the measuring grid, in bright daylight you will have to make it brighter in order to see the grid.
Pen with the inscription "Gain Y”Is essentially a coarse gain control for the vertical beam span. When measuring high-level signals, you will have to reduce the sensitivity level in order for it to fit into the oscilloscope screen. When looking for weak signals, you need to increase the sensitivity of the amplifier.
Below is a toggle switch, which is used to connect to the input of the measuring tank. This is done to cut off the DC current from the measurement. Only the alternating component of the signal gets to the amplifier.
Under it is a bayonet measuring input connector for a special adapter. The device is supplied with special probes for measurements, shielded wires, with a voltage divider. The probe does not distort the signal under test and the effect on the device under test is minimized. Typically, an oscilloscope comes with several types of probes for different types of measurements. Active probe - with its own amplifier. Passive without any additional elements other than the matching chain to reduce the effect of cable length on the input signal. And probes with a divider, in which it is possible to reduce the voltage amplitude 1:10 with a separate toggle switch; 1:100; 1:1000.
Below the bayonet is the output from the built-in square-wave generator. With its help, you can check the device of interest, as well as perform the initial calibration of the meter.
Under the oscilloscope screen, there are regulators with a scale:
- Switch "Gain»The voltage range is selected - volts / division. It is selected how many volts will fit into the division of the measuring grid of the screen, and you can visually determine the voltage value, knowing the range on the switch.
- A second dial switch measures the pulse width. Simply put, the measurement frequency. Signal duration per one division of the measuring grid.
- Regulator " Scan»Shifts the beginning of the pulse horizontally. They need to be used to shift the signal under investigation along the scale, in the case when the beginning of the pulse is obtained outside the scale.
- Entrance "NS»Allows you to use external generators to control the horizontal time base. In the case when the built-in is not enough, or is not stable, that is, the frequency floats. In this position, you can observe the figures of Lissajous. Intricate geometric patterns.
Below are the sync control knobs:
- Toggle switch "Internal External”The choice is made from which source the sweep will be synchronized. Simultaneously with the investigated signal or from the internal one.
- Regulator "Level»Changes the sensitivity, it depends on which edge of the signal will trigger the sweep, the rising or falling edge of the external signal.
- Toggle switch "- / ~" switches between single or self-oscillating sweep triggering. This mode is convenient for examining digital logic devices, where signals do not follow periodically, as in generators.
- Adjustment knobStability»Is the same as synchronization. This resistor is used to adjust the synchronization of the signal with the sweep. The sine wave of the beam stops running across the screen and freezes into a static picture, which can now be studied in more detail.
User manual
The oscilloscope needs to be calibrated before starting work. After plugging into the network, it is necessary for the device to warm up and stabilize. This usually takes 5 minutes. Regulators "amplifier Y" and "Scan»The beam is set in the center of the screen. After that, the brightness and focus are adjusted.
If the measuring probe touches the generator output, then we will observe on the screen rectangular pulses with a frequency of 1 kHz and 500 mV. When the regulator is in the “Duration"At the 1ms (millisecond) position. If everything is in order, then our device is ready for use.
When measuring the signal, the switches "Gain" and "Duration»Set to the extreme left positions. By amplification, the measurement range is raised to clear, maximally distinguishable signals on the screen, and the regulator “Duration»The frequency of the input signal is found out.
For reference, 1kHz (1000Hz) is 1ms, 1Hz is 1000ms.
When the signal is fixed on the screen, using a measuring grid, the signal voltage, period (frequency) is measured. Modern digital meters display this information directly on the device display, and the operator knows everything about the signal: voltage, duration, duty cycle, period. This concludes our brief explanation. We hope you now know how to use an oscilloscope and what this measuring device is for. Finally, we recommend that you watch the video instructions below, which show how to work with the most popular oscilloscopes.
Instructions for use of the device
How to use C1-67
s1-83
s1-65a
Digital model ASK-2203
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