Digibridge GENRAD GR1689



  • 群里高手提供的,我就是转载!
    先默默感谢!
    去机场路上,打发时间,全手机操作,搬运也辛苦,有错直接指出。

    77777 XXXX. Detector test failure; Digibridge hangs up. PROCEDURE: Switch POWER OFF and ON to clear hangup and repeat self check. He sure that the EXTERNAL BIAS switch is OFF. Use scope to check waveforms on the main board as indicated below and in the accompanying figure.原因:Detector 检测失败:数字桥挂起。处理:关闭电源再打开清除挂起并重新自检。确定外部偏置开关是OFF。使用示波器检查主板波形。下面列出了详细的故障现象和代码。 77777 7777. DBIG (U27 pin 2) is stuck low. Integration failure. PROCEDURE: check integrator output (U64 pin 7). Its acquisition, i.e. integration slope (downward) should cross the level of -5.1 V; then BIG-L (U64 pin 14) should go low and DBIG high,signaling the microprocessor to start conversion, i.e. Deintegration.原因:DBIG被钳位为低,积分失败。处理:检查积分器输出。可以获得,积分波形(负向)应该穿越-5.1V电平;然后BIG-L应该变低而DBIG变高,...... 77777 6666. DMSR (U27 pin 8) is stuck high. Integration failure. PROCEDURE: check MSR (U45 pin 11). Both of these signals should be low during integration. Check the circuit back through D flip-flop U45 to PMSR at U27 pin 10.原因:DMSR(U27第8脚)被钳位为高,积分失败。处理:检查MSR(U45第11脚)。积分期间这两个信号都应该为低。检查线路追溯到D触发器U45和U27第10脚的PMSR信号。 77777 5555. FCOUNT is not toggling (U27 pins 9, 40). Check the circuit back to frequency multiplexer U19 pin 9. Verify that all frequencies are present on the inputs to the multiplexer and that the control lines FDIVO and FDIV1 are functioning (U19 pins 2, 14, respectively). 77777 3333. DMSR (U27 pin 8) is stuck low. Integration failure. PROCEDURE: Check MSR (U45 pin 11). Both of these signals should go high, starting the deintegration. 77777 2222. CMP-L (U64 pin 8) is stuck high. Deintegration failure. PROCEDURE: check that integrator output (U64 pin 7) rises to cross the 0-V level at the end of deintegration. CMP-L should go low at that crossing, and may remain low for only a brief pulse. The leading edge should cause DMSR to go low and ISW (U45 pin 6) should go high. 77777 1111. DBIG (U27 pin 2) is stuck high. Deintegration failure. PROCEDURE: verify that BIG-L goes high and DBIG goes low when integrator output becomes more positive than -5.1 V. 66666 XXXX. Detector scale factor and zero bias test failure; the Digibridge will loop, automatically repeating the test and updating the display. XXXX is the magnitude of "zero" measurement, normalized to 1.COMMENT: The "zero" measurement includes a sequence of five dual-slope conversions (measurements of voltage coming into the detector from the instrumentation amplifier). Frequency is 1 kHz; test signal level is 75 mV. The signal component is removed by averaging the results of two dual-slope conversions, sampled in opposite phases. The detector is supposed to be biased so that its "zero" output is essentially in the center of its operating range. For convenie

    nce, the CPU divides the "zero" measurement by its normal value and displays the result. Consequently, the ideal value for XXXX is 1.000. If it is less than 0.875 or more than 1.125, the test fails.ANALYSIS PROCEDURE: Check the following circuits:1. Zero (half-scale) bias current circuit (CR38 , Rl16). NOTE: Rl16 is a 10-kilohm potentiometer, which should be adjusted for 2.5 V measured at the cathode of CR38. These components are found about 93 mm (3 5/8 in.) from the right front corner, measured toward center of board.2. Detector scale (integrator) current circuit (CR40, Rl19, U63).3. Phase control circuit (U26, U27, U21, U23, U18, U22).4. Detector switches (U63). 555 D XXXX. Signal strength check failure; the Digibridge will loop, automatically repeating the test and updating the display. The digit D indicates the range and voltage level used. (See below.) Test frequency is 1 kHz. 信号强度检测失败;数字桥循环,一直重复测试和更新显示。数字D指示了量程和电平。测试频率1kHz。 COMMENT: Possible cause is having EXTERNAl, BIAS switch ON during power-up. The effect depends on what is connected to the EXTERNAL BIAS connector and what is in the test fixture. This switch must be OFF to assure normal power-up routines,also, check to make sure that the charged capacitor protective fuse has not blown (Item 11, Figure 1-3), the effect is similar. The Digibridge separately squares the measurements of 4 component voltages, a quadrature pair across the DUT and a pair across the internal standard resistor. The squares are summed to represent the square of the applied voltage (essentially the open-circuit voltage from the HIGH terminals of the test fixture to ground. To normalize this result, it is divided by the square of the "zero" measurement.(See 66666 XXXX, above.) The ideal value for XXXX is about 0.64. If it is less than 0.250 or more than 1.000, this test fails.ANALYSIS PROCEDURE: See below; depends on the failure display, which is coded to indicate test voltage (high or low) and range of the failed test. 555 50000. (Confirming symptoms: If you press START repeatedly until the instrument completes its self check,the BIAS ON indicator will be lit even though the EXTERNAL BIAS switch is OFF, no bias is applied, and INT BIAS has notbeen selected.) The fault is probably in the 6-wire connection between keyboard and main board. Check to be sure that the cable connector properly engages all 6 pins at the keyboard. 5555 XXXX. Low voltage (75 mV rms), range 4. If XXXX is less than 0.250, check for a malfunction in the circuits that supply the test signal Ih (U32, U31, U14, U13, U44 ...back to U4). Check the input signals and the gain through instrumentation amplifier U61.However, if XXXX is greater than 1.000, check the test voltage and source resistance selector circuits (U32,controlled by U27 pins 6, 7); check filter selector U13, controlled by U27 pins 12, 13, as well as pins 14, 15, via U21 and U38.Also check for RAWSINE on D/A converter U44 pin 15. 5554 XXXX. High voltage (1.275 V), range 4. Check test voltage selector circuit and instrumentation amplifier. 555 3 XXXX. High voltage (1.275 V), range 3. Check signal at Ih terminal with test fixture shortcircuited. Check signal at output of transconductance amplifier circuit (U58 pin 8) with test fixture short circuited. 555 2 XXXX. High voltage (1.275 V), range 2. (See previous suggestion.) 555 1 XXXX. High voltage (1.275 V), range 1. (See previous suggestion.) 444 E XXXX Test frequency and waveform check failure; the Digibridge will loop, automatically repeating the test and updating the display. The digit E indicates the frequency used in the test. (See below.) High voltage test signal is used, on range 4. COMMENT: Measurement, summing of squares, and normalization are exac

    tly as described for 555 D XXXX. Also the failure limits for XXXX are the same (0.250 and 1.000), except for tests 1 and 2, which have the limits: 0.125 and 1.000. ANALYSIS PROCEDURE: check for the generation of the proper frequency (indicated in code by failure display, see below) by U5, U6, U7,U8, U20, U17, U18, U19, U22. Check filter circuitry in signal source (U13) and detector (U62, U40, U41). Operation can usually be enabled, in spite of failure messages "444 1 XXXX" or "444 2 XXXX"), by pressing the START button.444 6 XXXX. .0118 kHz.444 5 XXXX. .0968 kHz.444 4 XXXX. 0.480 kHz.444 3 XXXX. 1.200 kHz.444 2 XXXX. 6.000 kHz.444 1 XXXX. 6.0606 kHz. 33333 XXXX. PROM data checksum failure. If the checksum XXXX is not 0000, check all digital circuitry,starting with the 6502 microprocessor U30. Any error on the address or data bus could cause a checksum error ---check ROM U35, check RAM U36, U34; check all of the PIAs U3, U25, U26, U27. Look for address or data lines stuck at about 2 V or stuck low. 222 F XXXX. Calibration constants check failure; Digibridge hangs up, but will respond to keyboard inputs. The digit F is the range in question. COMMENT: Each check consists of a comparison between the stored calibration data for the range and the normal, expected values. The calibration can be expressed (essentially) as the conductance of the internal standard resistor. The Digibridge normalizes this conductance by dividing it by the nominal conductance of the standard, and displays the result, XXXX, which should be very close to 1.000. (See table giving source resistance for each range in paragraph 3.4.2.) If xx:xx is less than 0.2187 or more than 1.781, this test fails. ANALYSIS PROCEDURE: depends upon display; see below.NOTE: This is a non-catastrophic failure. If you press the [Cs/D] key, the Digibridge will proceed with the selfcheck routine. The instrument can be operated as usual, but results may be erroneous. To restore accuracy, recalibrate, as described in paragraph 5.9.222 4 XXXX. Range 4 may be incorrectly calibrated. Refer to paragraph 5.9 for recalibration procedure. If calibration is accomplished correctly, but this failure display appears when POWER is cycled OFF and ON, check battery Bl.(See Figure 6-4. Connect voltmeter only briefly.) If Bl voltage is less than 2.0 V, replace battery with a new one, as described in paragraph 5.7.3. If the problem is clearly associated with the loss of calibration when POWER is cycled OFF and ON, but the battery voltage is adequate, check the standby power circuit (Q9, Q10, CR9, CRl5). Only if necessary, check Rs standard switching circuitry (R96 through R99, U36 pin 1, U27, U56, U57, U58). 量程4也许没有正确校正,可参考5.9节重新校正。如果校正正确完成,但是这个错误在开机后还会出现,检查电池B1。如果B1电压低于2.0V,换一个新电池,如5.7.3所描述。如果问题和电源开机后丢失校正数据明确关联,但是电池电压又是充足的,检查电源待机电路(Q9,Q10,CR9,CR15)。尽在必要时,检查Rs标准开关电路(R96到R99,U36的1脚,U56,U57,U58)。 222 3 XXXX. Range 3. Be sure that recalibration has been done correctly. If necessary, check Rsstandard switching circuitry as described above. 量程3。确定已经正确的重新校正,如果需要,如上所述检查Rs标准开关电路。222 2 XXXX. Range 2. Same comment as for range 3. 222 122 1 XXXX. Range 1. Same comment as for range 3.222 0 XXXX. Frequency correction factor. ANALYSIS PROCEDURE: refer to 444 E XXXX.11111 1111. Math chip operational check failure. COMMENT: This test is performed only if you have the high-speed interface option 1689-9620 installed.NOTE: This is a non-catastrophic failure. If you press the [Cs/D] key, the Digibridge can be operated as usual,but measurement time will be typical of an instrument WITHOUT the high-speed option. 5.7.3 Battery and Fuse ReplacementBATTERYIf, at power-up, there is a failure display of 222 4 xxxx and investigation shows the most likely cause to be low battery voltage, you probably should replace battery Bl. (See power-up self check in paragraph 3.13 and above in 5.7; see part description in Table 1-3 and/or Section 6.) The procedure is as follows.a. Remove the main board.b. Find Bl at the right of center (see Figure 6-4). Cut its straps. Observe correct polarity, for replacement, + toward center of board.SERVICE 5-33WARNINGWear safety glasses while doing any work on the battery. DO NOT short or apply voltage to thebattery. Dispose of the old one in accordance with local regulations for disposal of hazardous materials. DO NOT incinerate.c. Usolder and remove the old battery with care not to overheat.d. Install the replacement and secure with straps (like the originals) or lacing cord, to safeguardterminals from strain.e. Solder the terminals with care and DO NOT overheat.f. Perform complete calibration procedure. Refer to paragraph 5.9. 222 4 XXXX. Range 4 may be incorrectly calibrated. Refer to paragraph 5.9 for recalibration procedure. If calibration is accomplished correctly, but this failure display appears when POWER is cycled OFF and ON, check battery Bl.(See Figure 6-4. Connect voltmeter only briefly.) If Bl voltage is less than 2.0 V, replace battery with a new one, as described in paragraph 5.7.3. If the problem is clearly associated with the loss of calibration when POWER is cycled OFF and ON, but the battery voltage is adequate, check the standby power circuit (Q9, Q10, CR9, CRl5). Only if necessary, check Rs standard switching circuitry (R96 through R99, U36 pin 1, U27, U56, U57, U58).量程4需要正确的校正。第5.9节是关于校正的。如果校正已经正确完成了,但是把电源开关一个周期后这个故障代码依旧出现,检查电池B1(见图6.4,短暂的连接一下电压表)。如果B1的电压低于2.0V,就需要换一个新的如5.7.3节描述的电池。如果故障很明显的与电源关机后丢失校正数据关联,而电池的电压又是合适的,检查备用电源电路(Q9, Q10, CR9, CRl5)。如果需要的话,检查标准电阻开关电路(R96 到R99, U36 脚1, U27, U56, U57, U58)。

    1689_im.pdf
    1689.1.pdf
    1689.2.pdf
    1689.3.pdf

    1689.4.pdf

    DigibridgeSchematicSlopedFront.pdf
    GENRAD 1659 Instruction.pdf



  • @redtony GR1689 重量级的低频电桥,型号不要写错



  • @mytek ,谢谢,已改!