Hameg HM604 Oscilloscope 电路图.pdf

Table of contents Technical Data.P 1 Accessories. . . . . . . . . . . . . . . . . . . . .Z 1 Operating Instructions General Information.M 1 Use of tilt handle.M 1 Safety.M 1 Operating conditions.M 2 Warranty.M 2 Maintenance.M 2 Mains/Line voltage change.M 2 Type of Signal.M 3 Amplitude Measurements.M 3 Time Measurements.M 4 Connection of Test Signal.M 5 Operating.M 6 First Time Operation.M 7 Trace Rotation TR.M 7 DC Balance Adjustment.M 7 Use and Compensation of Probes.M 8 Operating Modes of the Y Amplifier.M 9 X-Y Operation.Ml 0 X-Y Phase Measurements.Ml 0 Dual Trace Phase Difference Measurements. . M 10 Measurement of an amplitude modulation.Ml 1 Triggering and Timebase.Ml 1 Triggering of video signals.Ml 2 Function of variable HOLD OFF control.M l 3 Sweep Delay /After Delay Triggeringe.Ml 3 Delay Mode Indication.Ml 5 Component Tester.Ml 5 Miscellaneous.Ml 7 Test Patterns.Ml 8 Short InstructionK 1. Front Panel Elements Folder with Front View.K 2 Test Instructions General.T 1 Cathode-Ray Tube: Brightness, Focus, Linearity, Raster Distortions . T 1 Astigmatismus Check.T 1 Symmetry and Drift of thevertical Amplifier.T 1 Calibration of the Vertical Amplifier.T 1 Transmission Performance of the Vertical Amplifier . . . . . . . . . . . . . . . . . . . . . . . . . . . . T 2 Operating Modes: CH I/II-TRIG. l/II, DUAL, ADD, CHOP., INV. l/II and XY-Betrieb . T 2 Triggering Checks.T 3 Timebase.T 3 SweepDelay.T 4 Component Tester.T 4 Trace Alignment.T 4 Miscellaneous.T 4 Oscilloscope HM 604 Service Instructions General. . . . . . . . . . . . . . . . . . . . . . . S 1 Instrument Case Removal. . . . . . . . . . . . .S 1 Operating Voltages . . . . . . . . . . . . . . . . .S 1 Minimum Brightness . . . . . . . . . . . . . . . .S 1 Astigmatismus control. . . . . . . . . . . . . . .S 1 Trouble Shooting the Instrument . . . . . . . . . . S 2 Replacement of Components and Parts. . . . . . S 2 Replacement of the Power Transformer. . . . . . S 2 Adjustments. . . . . . . . . . . . . . . . . . . . S 3 Circuit Diagrams Block Diagram.D 1 Wiring Diagram.D 2 Identification of Components.D 3 Y Input, Attenuator, Preamplifier CH. l/II.D 4 Y intermediate Amplifiers, Trigger Pre-Amplifiers, Component Tester.D 5 Y Final Amplifier.D 6 Post Trigger, Field Selector.D 7 Timebase (analog).D 8 Timebase (digital).D 9 Tim,ebase Generator.DlO X Final Amplifier, Calibrator.Dl 1 CRT and HV circuit.D12 Power Supply.D13 Component Locations XY Board.D14 TB Board.D15 PTFS Board.D16 TBG, CAL, YF Boards.D17 CO, EY, Z Boards.D18 Subject to change without notice9.88. 604 RadioFans.CN 收音机爱 好者资料库 Specification Vertical Mhtion Operating modes: Channel I or Ch. II separate, Channel I and II: alternate or chopped. (Chopper frequency approx. 0.5MHz). Sum or difference of Ch. I and Ch. II, (with invert buttons for both Channels). XY-Mode: via Channel I and Channel II. Frequency range: 2x DC to 6OMHz (- 3dB). Risetime: approx. 5.8ns. Overshoot: II %. Deflection coefficients: 12 calibrated steps from 5 mV/div. to ZOV/div in l-Z-5 sequence, variable 2.5: 1 to min. 50V/cm. Accuracy in calibrated position: +3%. Y-Magnification x5 (calibrated) to 1 mV/div. (Frequency range DC to 20MHz. - 3dB. input impedance: 1 MQ II 3OpF. Input coupling: DC-AC-GD (Ground) Input voltage: max. 400V (DC + peak AC). Y-output from CH I or CH II, = 50 mV,Jdiv. (50 52) Delay Line: approx. 90ns. Trigger System With automatic lOHz-IOOMHz (P5mm height) normal with level control from DC- 100 MHz. LED indication for trigger action. Slope: positive or negative. Sources: Ch. I, Ch. II, line, external. Coupling: AC (21 OHz to approx. 20 MHz), DC LF (DC - 550 kHz), HF(?50kHzmlOOMHz). Threshold: external r50mV. Active TV-Sync-Separator for line and frame. Slope positive or negative. 2nd. Triggering (Del. Trig.): autom. or slope con- trolled (independent from slope direction). + selection for TV mode. Threshold: 1 div; typlcal 0.5div. Trigger bandwidth: 225 Hz to 60 MHz. Time coefficients: 23 calibrated steps from 50ns/div. to 1 s/div in l-2-5 sequence, variable 2.5: 1 to min. 2.5s/div, accuracy in calibrated position: +3%. with X-Magnifier x10 (k 5%) to = 5nsIdiv. Hold-Off time: variable (2 5 : 1). Delay: 7 decade steps from 1 OOns to 0.1 s, variable approx 10 : 1 to 1 s. Bandwidth X-Amplifier: DC-5MHz (-3dB). Input X-Amplifier via Channel II, sensitivity see Ch. II specification. X-Y phase shift: SOMHz), as otherwise strong overshoot or rounding may occur, when measuring fast-rising square waves. An exact HF-compensation, however, is only possible with square- wave generators having a risetime <5ns. Most HAMEG scopes already feature such a calibration generator. For other oscillo- scopes, it is available as accessory item HZ60-2. At present the following Modular Probes are available (HZ36 without HF-com- pensation): Type HZ36HZ51HZ52HZ53 selectable Attenuation Ratiol:l/lO:l 1O:l IO:1 (HF) 1OO:l Bandwidth min. (MHz)IO/ 100150250150 Risetime (ns)3513.5 <2t l . 4<2 Inp. Capacitance (pF)47/1816 1665 Inp. Resistance (MR)l/101010100 Inp. Voltage max. (V,)600600 6001200 Cable Length (m)1.51.2 1.51.5 Spare Cable for HZ36 Spare Cable for HZ51, HZ54 Sparepart Kit (2 sprung hooks, 2 screw tips, 1 ground cable) HZ54 selectable 1:1/10:1 IO/ 150 35/ 16OV, with probe X 10 : U = 62.2 V,), desired display height H = min. 3.2cm, max. 8cm. max. deflection coefficient D = 62.2 : 3.2 = 19.4V/cm, min. deflection coefficient D = 62.2 : 8 = 7.8V/cm, adjusted deflection coefficient D = lOV/cm If the applied signal is superimposed on a DC (direct voltage) level the total value (DC + peak value of the al- ternating voltage) of the signal across the Y-input must not exceed *4OOV(see figure). This same limit applies to normal x 10 attenuator probes, the attenuation ratio of which allows signal voltages up to approximately 1 ,OOOV, to be evaluated. Voltages of up to approximately 2,4OOV, may be measured by using the HZ53 high voltage probe which has an attenuation ratio of 100: 1. It should be noted that its ACpeakvalue is derated at higher frequencies. If a nor- mal x 10 probe is used to measure high voltages there is the risk that the compensation trimmer bridging the attenuator series resistor will break down causing damage to the input of the oscilloscope. However, if for example only the re- sidual ripple of a high voltage is to be displayed on the oscil- loscope, a normal x 10 probe is sufficient. In this case, an ap- propriate high voltage capacitor (approx. 22-68nF) must be connected in series with the input tip of the probe. Voltage DC + AC,k = 4OOV,. I peak AC DC Fu .-. DC/ / / AC /-1 Time . 1 / c I 1 ! / Total value of input voltage - / ,/ The dotted line shows a voltage alternating at zero volt level. When superim- posed a DC level, the addition of the positive peak and the DC voltage results in the max. voltage (DC + AC,). T = L.T,T, = ; 1 F - = L.Tc 1 L = F.Tc T, = e displayedcyc,e I v HOLD-OFF time Fig. 1 shows a case where the HOLD-OFF knob is in the Xl position and var- ious different waveforms are overlapped on the screen, making the signal observation unsuccessful. Fig. 2 shows a case where only the desired parts of the signal are stably dis- played. Sweep Delay / After Delay Triggering With the sweep delay, the start of the sweep can be de- layed from the trigger point by a selectable time (IOOns to maximum 1 s). It is therefore possible to start the sweep at practically any point of a waveform. The interval, which fol- lows the start of the sweep, can be greatly expanded by the increase of the sweep speed. From the 5 p/cm TIMEIDIV. range downwards to slower sweep speeds, an expansion of at least 100 times, and with the aid of the X MAG. x10 ex- pansion of 1000 times, is possible. With time coefficients higher than 5cm, the maximum expansion increases proportionally. However, with increasing the expansion, the display brightness decreases. Under very high ambient light conditions a Viewing Hood like HZ47 can overcome this problem. It should be noted that there are some difficulties with higher expansions, if the test signal has inherent jitter. To reduce or eliminate this jitter, expanded parts of a signal can be triggered again“after delay” provided there is another suitable edge (DEL. TRIG.). In DEL. TRIG. mode andN SEP. switch in H or V position, after delay triggering to the next following line is possible. Therefore discrete lines are representable. The slope is ap- pointed by the TV+ or N- position of the delay switch. When not in TV-trig. mode the susceptibility to interference (sense) can be influenced (A = normal, v = reduced). Operation of the sweep delay is relatively easy, as normally only 3 controls in the X-Section need to be used: the DELAY operating mode lever switch (OFF-SEARCH-DELAY-DEL. TRIG.), the DELAY rotary switch (delay time range), and its variable control VAR. IO:1 (small knob on the DELAY switch). The latter, a twenty-turn precision potentiometer with overwind protection, can increase the delay time range tenfold. An LED near the DELAY mode switch indicates the operating mode. For reliable operation of the sweep delay, it is recom- mended that the following procedure should always be adopted; also reference to the accompanying figures will be of assistance. Figure 1 MODE: NORM. TIME/DIV.: 0.5 ms/cm LED: off Initially, the sweep delay mode lever switch should be set in the OFF position. In this mode, the complete waveform under investigation will be displayed as for normal oscillo- scope operation. The mode indicator LED is not illuminated in OFF mode. The time coefficient on the TIME/DIV. switch is selected so that 1 to 3 basic periods of the signal are displayed. A larger number unnecessarily decreases the brightness and maximum expansion. The display of only a portion of a period limits the choice of the expanded time in- terval and possibly complicates the triggering. On the other hand, the range of 1 to 3 basic periods can always be set un- constrainedly with the TIME/DIV. switch. In doing so, the x10 expansion must be switched off temporarily (X MAG. x10 button is in out position). In the X-Section, the HOLD-OFF control should be set to min. and the variable control to CAL.The LEVEL control is adjusted so that stable triggering is ensured (TRIG. LED is illuminated). The mode switch should now be set to the SEARCH posi- tion; it will be seen that the start of the display will shift to the right. The amount of shift indicates the exact delay time. Subject to change without noticeMl3 604 If a display is not obtained in this mode, then a lower delay time range should be selected. For example, when inves- tigating the waveform shown in the figures, a display could not be obtained with a delay time setting of IOms, as the display is completely blanked. However, as a result of set- ting the DELAY rotary switch to 0.1 ps, the shifting is not visible. The DELAY range switch should then be rotated clockwise until the display starts just prior to the short time interval to be investigated. The precise adjustment to the start is done with the VAR. 1O:l delay time control. The rotating range of the latter has no stop. On the range limits a certain snapping noise is audible. Initially, this control should be set in the left start position. In the SEARCH mode, the LED indicator will flash. Figure 2 MODE: SEARCH DELAY range:lms TIME/DIV.: 0.5 mskm LED: flashing Delay time = 2.5cm . 0.5mskm = 1.25ms In figure 2 it can be seen that the delay time is also measur- able as the blanked portion or apparent shift of the start of the trace. This time can be determined by multiplication of (the horizontal shifting in cm) by (the time coefficient set on the TIME/DR!. switch). Now the mode switch can be set to DELAY. In this mode, the LED is permanently illuminated. The display will now shift to the left and the trace will commence in the same po- sition as for a normal display; however, the short time inter- val under investigation now starts on the first or left vertical graticule line. Figure 3 MODE: DELAY DELAY range:lms TIME/DIV.: 0.5 ms/cm LED: illuminated If the timebase sweep speed is increased (rotate TIME/ DIV. switch clockwise), then the short time interval will be expanded. It may be found that, as the amount of expansion is increased, the trace will tend to shift. If this happens, the VAR. delay time control can be readjusted - also sub- sequently at any time - to enable the exact point of interest to be displayed. In the example shown in figure 4, it can be seen that an ex- pansion of x10 was obtained by increasing the timebase sweep speed from O.Sms/cm to 5Ops/cm. Also the pre- cise measurement for the delayed portion of the waveform is possible. In the example, this was found to be 250s on multiplication of the horizontal length in cm (of an optional signal section) by the time coefficient just adjusted. Figure 4 T- MODE: DELAY DELAY range:lms TIME/DIV.: 50 cm LED: illuminated Expansion:o.510-3:5010-6=10 T = 5cm. 50cm = 250s Operation of the sweep delay requires a constant trigger point. All signals, which have a constant phase shift be- tween the expanded section and trigger point, pose no problems. This means all electrical signal shapes, which contain signal edges of the same polarity and with trigger- able level values, which are constantly repeated with the re- curring frequency. If there is no constant phase shift, the triggering may fail after switching from the SEARCH to DELAY position or with changing of the time coefficient. It is best to attempt to find a trigger point, which has a constant phase shift up to the signal section to be expanded in the OFF mode. With complicated composite signals, the display of the basic period could become superimposed by other signal por- tions. These dissappear as a rule when the sweep is in- creased. Otherwise, a stable expanded display is obtained by adjusting the LEVEL and the variable sweep control or by means of the HOLD-OFF control. Using the X MAG. x10 button, a tenfold expansion of the desired signal section is possible without any change of trig- gering or timebase. This can be of assistance