Stanford Research Systems DS345, Руководство пользователя

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Troubleshooting
4-3
Units Error The units set with AMPL command are not V
pp
,V
rms
, or dBm.
Volt Error The output voltage is outside of 0.01V
pp
to 10V
pp
range.
Self-Test Errors
These errors may occur during the DS345's self- test. In general, these mes-
sages indicate DS345 hardware problems. If the errors occur repeatedly the
unit may have an electrical problem. The messages are listed alphabetically,
also listed is the status value returned by the *TST? command.
Message Status Value Meaning
AD Offs Err 8 The DS345's A/D converter has an excessive DC offset (> ± 75mV). This
can mean a problem with the D/A or A/D circuits.
AD Gain Err 8 The DS345's A/D converter has the wrong gain (A/D measures the 5.00V ref-
erence voltage). Can be a problem with the D/A or the A/D multiplexer.
Cal Data Err 4 The RAM calibration data has become corrupt. The factory values will be re-
loaded from ROM. This message is not a problem unless it occurs frequent-
ly, which could indicate a problem with the battery backup circuits.
Code Err XX 2 The DS345's ROM has a checksum error. XX is the checksum value.
CPU Error 1 The DS345 has detected a problem in its Z8800 Cpu.
DAC OFF Err 10 The waveform DAC output offset control (carrier null) doesn't work (should
have 75mV to 225mV range at output BNC).
DDS DAC 1 Er 4 Error in linearity of ASIC controlled gain DAC (U412A). Checked at full, 1/2,
1/4, and 1/8 scale.
DDS DAC 2 Er 4 Error of ASIC controlled offset DAC (U412B). Checked at 0V, ±full scale.
DDS DAC 3 Er 4 Error in linearity of mimic DAC (U401). Checked at full, 1/2, 1/4, and 1/8
scale.
Doubler Error 12 Error in frequency doubler circuitry or Cauer filter.
Fn Data Err x 5 Error in read/write to waveform RAM. x = 1 = U305, 2 = U306, 3 = U307.
Can indicate problem with RAMs, ASIC, or bus interface circuits.
Func DAC Err 10 The waveform DAC (U500) cannot generate ±full scale output.
Func Off Err 10 The waveform DAC or amplitude control multiplier (U500 and U702) have ex-
cessive DC offset (> ±200mV or ±450mV respectively).
Gain Ctl Err 10 The amplitude control multiplier (U702) has linearity problem. Checked at
full, 1/2, and 1/4 scale.
Gain FS Err 8 Amplitude control DACs (U109B and U412A) full scale output is > ±20% from
nominal.
note:
this error can be caused by a signal being applied to the ex-
ternal AM input.