Keysight (Agilent HP) E4401B Repair Service
Product model
E4401B ESA-E Spectrum Analyzer, 1kHz to 1.5 GHzServices
Expert repair and calibration for your Agilent HP E4401B Spectrum Analyzer. We specialize in obsolete, unsupported equipment. Free evaluations.
Description
•1.1 dB overall amplitude accuracyrn•100 Hz to 5 MHz RBW, 100 Hz to 300 Hz optionalrn•+7.5 dBm TOIrn•5 minute warm-up to guaranteed measurement accuracy
Repair prices
Any failures or unforeseen issues identified during the calibration phase will be detailed in an estimate submitted for your approval prior to any further action. Repair charges are determined by the actual time and materials required. Please be aware that customers are responsible for all associated shipping costs, to and from our location. This initial estimate is provided free of charge.
E4401B Specifications – click to expand
E4401B Specifications
•1.1 dB overall amplitude accuracyrn•100 Hz to 5 MHz RBW, 100 Hz to 300 Hz optionalrn•+7.5 dBm TOIrn•5 minute warm-up to guaranteed measurement accuracy
E4401B Options – click to expand
E4401B Options
- 1 kHz RBW and 1 kHz VBW
- (measurement time)rn≤ 150 Hz x Ncrn (100 ms) ≤ 10 Hz x Ncrn (20 ms),
- Option 1DR ≤ 2 Hz peak-to-peak x Ncrn, (20 ms),
- Option 1DR and 1D5
- Option PFR ≤ 0.25 Hz x Nc
- (20 ms nominal)
- Option 1D5 only 100 ms ≤ 100 Hz x Nc Standard ≤ 10 Hz x Nc
- (20 ms nominal)
- Option 1DR only 20 ms ≤ 10 Hz x Nc
- Option 1DR and 1D5 only 20 ms ≤ 2 Hz peak-to-peak x Nc
Agilent / HP E4401B Error Codes – click to expand
Agilent E4401B Error Codes and Messages
Error and status messages for the Agilent E4401B ESA-E spectrum analyzer. Numbered errors appear in the error queue (System, Show Errors); status messages appear in the upper-right of the display. Hardware-related messages are listed first.
E4401B notes
- The E4401B is an ESA-E analyzer to 1.5 GHz. This list uses the ESA numbering (108 is Cal Oscillator Unlock, 600-series file errors use ESA numbers).
- The E4401B is a 1.5 GHz model: one A8 RF assembly, optional 1.5 GHz tracking generator (Option 1DN 50 Ω / 1DQ 75 Ω) and input overload protection. Disconnect the INPUT before running Align Now, All.
- The E4401B accepts the E-series options such as Option 1D5 precision frequency reference, AYX fast ADC and BAA FM demod.
E4401B hardware and alignment errors
| Error | Message | Meaning |
|---|---|---|
| 64 | Align All Now Needed | The stored alignment data is no longer valid. Run System, Alignments, Align Now, All. If the message comes straight back, or the alignment itself fails, there is a hardware fault in the signal path being aligned. |
| 102 | Excessive 50 MHz RF input power is preventing internal alignments | Too much 50 MHz energy is at the RF input for the internal alignment to run. Bring the input below 0 dBm and align again. |
| 103 | Sampling Oscillator Unlock | The sampling oscillator that helps lock the first LO has lost lock. This is a hardware fault: on the E4401B the LO circuits are part of the A8 1.5 GHz RF assembly. |
| 104 | 1st LO Unlock | The first LO cannot hold phase lock. Usually hardware: on the E4401B look at the A8 1.5 GHz RF assembly. |
| 105 | 2nd LO Unlock | The second LO has lost phase lock. On the E4401B this is on the A8 1.5 GHz RF assembly. |
| 106 | 4th LO Unlock | The fourth LO in the IF chain has lost phase lock. On the E4401B suspect the A3 IF assembly. |
| 107 | Sample Clock Unlock | The ADC sample clock has lost lock. On the E4401B suspect the A3 IF assembly or its reference input. |
| 108 | Cal Oscillator Unlock | The internal calibration oscillator has lost lock, so alignments and amplitude accuracy are affected. On the E4401B the calibrator is part of the A8 1.5 GHz RF assembly. |
| 143 | Final IF Overload | The final IF stage is overdriven. Add input attenuation or lower the signal. If it shows with no signal connected, suspect the IF section. |
| 197 | Marker Freq Count HW Failure | The marker counter hardware did not return a valid count. A persistent failure points to the IF/counter circuitry. |
| 206 | Unable to initialize flatness data | Flatness correction data in the internal EEROM could not be set up. Amplitude flatness will be wrong until the data is restored; this needs service. |
| 207 | Unable to store flatness data | Writing flatness correction data to the internal EEROM failed. Usually means a memory problem or a failed adjustment; needs service. |
| 622 | External reference missing or out of range | External reference is selected but the signal at EXT REF IN is missing, too low, or not at the frequency entered. If it appears on internal reference, suspect the reference circuitry. |
| 651 | Connect RF OUT to INPUT | A tracking generator alignment was started without the TG RF OUT cabled to the analyzer INPUT. Connect it and repeat. |
| 653 | Auto Align not available when using Calibration Defaults | Calibration defaults are loaded, so auto alignment is off until Align Now, All has been run successfully. |
| 767 | Failed to Initialize ISTATE regions. Fatal LDS error | The instrument state memory could not be initialized at power-up. Cycle power; if it repeats, the processor or its memory needs service. |
E4401B status messages
| Status message | Meaning |
|---|---|
| 50 MHz Osc Unlevel | The internal 50 MHz amplitude reference is unleveled. Alignments cannot run correctly until this is fixed; points to the calibrator/reference circuitry. |
| First IF Overload | The first IF is overdriven. Increase attenuation or reduce the input; with no input applied it indicates an RF/IF fault. |
| Frequency Reference Error (Freq Ref Unlocked) | The frequency reference loop is unlocked or near unlock. On external reference, check the source matches the entered value; on internal reference it is a reference-board fault. |
| LO Unlock (Synth Unlocked) | The LO phase-lock circuitry is unlocked. Readings are invalid until it is repaired. |
| LO Unlevel (LO Unleveled) | The LO drive is unleveled inside the instrument, causing low or unstable signal levels. |
| ADC / IF / LO / RF Align Failure | Status bits that are set when a particular alignment routine fails. The failing routine identifies the section to troubleshoot. |
| Source LO Unlock / Source Unlevel | Tracking generator LO lost lock, or TG output cannot hold the set level. Check frequency and power are inside TG limits first; otherwise a TG board fault. |
| Overload: Reduce Signal and press | The input overload protection tripped on this 1.5 GHz model. Reduce the signal and press ESC. Long exposure to high input power can damage the input. |
E4401B setup messages
| Error | Message | Meaning |
|---|---|---|
| 129 | Meas Uncal | Sweep is too fast for the RBW/VBW. Increase sweep time or press Auto Couple. |
| 163 | Freq Count: Reduce Span/RBW ratio | Span is too wide for the RBW to count a marker. Narrow the span or widen the RBW. |
| 201 | Option not installed | The function needs an option this unit does not have. |
| 202 | No peak found | No signal met the peak search criteria. |
| 204 | TG Frequency Limit | The tracking generator has reached the end of its frequency range. |
| 211 | RBW limited to 1 kHz when Span > 5 MHz | Digital RBWs under 1 kHz are only available in narrower spans. |
| 214 | TG start freq is less than 9 kHz | Tracking generator is uncalibrated below 9 kHz. |
| 224 | Option not licensed | The option is present but has no license key installed. |
| 751 | Instrument state set to initial values | A saved or power-on state was corrupt and defaults were loaded. |
| 757 | Unable to load user state, factory preset was done | The user preset is invalid; save a good state as the user preset. |
| 769 | Invalid instrument mode | The requested measurement personality is not installed. |
E4401B file and storage errors
| Error | Message |
|---|---|
| 604 | File exists |
| 605 | Media is protected |
| 607 | File name error |
| 609 | Media is not writable |
| 612 | File not found |
| 613 | Flash memory is full |
| 614 | Bad, missing, or unformatted disk |
| 615 | File is corrupt |
| 617 | Wrong density floppy inserted |
E4401B SCPI error ranges
| Range | Class |
|---|---|
| −100 to −199 | Command errors (syntax, header) |
| −200 to −299 | Execution errors (setting out of range, not allowed now) |
| −300 to −399 | Device-specific errors (queue overflow, self-test, memory) |
| −400 to −499 | Query errors (unterminated or interrupted query) |
LO unlock, alignment failure or IF overload on your E4401B? Analyzer Repair Inc. repairs and calibrates the Agilent E4401B in-house in Cocoa, Florida, including YTO, RF assembly, synthesizer and IF board faults. Free estimate once the unit is in our lab. Contact us for service.
Message numbers from Agilent ESA/PSA Instrument Messages and Functional Tests (E4440-90619); assembly references from the Agilent ESA Spectrum Analyzers Service Guide.
Agilent / HP E4401B Replaceable Parts – click to expand
Agilent E4401B Replaceable Assemblies and Part Numbers
Major replaceable assemblies for the Agilent E4401B with Agilent part numbers from the Agilent ESA Spectrum Analyzers Service Guide. Option-only parts are marked in the Notes column.
| Reference | Assembly | Agilent part number | Notes |
|---|---|---|---|
| A1A1 | Front panel interface board kit | E4401-60241 | |
| A1A1A1 | Rotary pulse generator (RPG) | 1990-1865 | |
| A1A2 | LCD assembly kit | E4401-60242 | Serial prefix US4119 and above (earlier units take E4401-60241 and E4401-60242) |
| A1A2DS1/DS2 | Display backlight | 2090-0577 | Upper and lower |
| A1A3 | Front frame assembly | E4401-60257 | Except Option 060 |
| A1MP5 | Main keypad | E4401-40002 | |
| A2 | 1.5 GHz tracking generator, 50 Ω | E4401-60128 | Option 1DN |
| A2 | 1.5 GHz tracking generator, 75 Ω | E4401-60129 | Option 1DQ |
| A2A1 | 1.5 GHz TG control board kit | E4401-60131 | Option 1DN/1DQ |
| A2A2 | 1.5 GHz TG RF board kit, 50 Ω | E4401-60133 | Option 1DN |
| A2A2 | 1.5 GHz TG RF board kit, 75 Ω | E4401-60134 | Option 1DQ |
| A2A3 | 1.5 GHz TG output board, 50 Ω | E4401-60135 | Option 1DN |
| A2A3 | 1.5 GHz TG output board, 75 Ω | E4401-60136 | Option 1DQ |
| A3 | IF assembly with shields | E4401-60183 | |
| A4 | Processor assembly, enhanced memory | E4401-60233 | Option B72 |
| A4A1 | Flash SIMM, 4 MB | E4401-60105 | 12 MB E4401-60081 with Option B72 |
| A4A2 | DRAM SIMM, 32 MB | E4401-60289 | Option B72 |
| A4MAU58 | Lithium battery, 3 V | 1420-0556 | |
| A5 | Power supply assembly | E4401-60186 | |
| A5B1 | Fan | 3160-0866 | |
| A6 | Speaker/floppy assembly | E4401-60008 | |
| A7 | Motherboard, ESA-E series | E4401-60107 | |
| A7A1 | IF/video/sweep ports | E4401-60096 | Option A4J |
| A7A2 | GPIB assembly | E4401-60013 | Option A4H |
| A7A3 | RS-232 assembly | E4401-60014 | Option 1AX |
| A7A5 | Fast ADC assembly | E4401-60083 | Option AYX |
| A7A6 | FM demod assembly | E4401-60343 | Option BAA |
| A7A12 | IF out assembly | E4403-60076 | Option H55 |
| A7A12 | IF out assembly | E4404-60034 | Option H70 |
| A8 | 1.5 GHz RF assembly, 50 Ω | E4401-60294 | Exchange E4401-69294 |
| A8 | 1.5 GHz RF assembly, 75 Ω | E4401-60100 | Option 1DP |
| A8A1 | Precision frequency reference | E4401-60036 | Option 1D5 |
Part obsolete? Many E4401B assemblies are no longer sold new. Analyzer Repair Inc. repairs E4401B RF assemblies, YTOs, IF and synthesizer boards at the component level in Cocoa, Florida. Free estimate once the unit is in our lab. Contact us for service.
From the Agilent ESA Spectrum Analyzers Service Guide.
Located in: Spectrum Analyzers