AugerScan – Electron Multiplier Voltage Logic

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The AugerScan software that is used on older Physical Electronics (PHI) AES and XPS surface analysis systems provides for control of data acquisition electronics such as analyzer controllers and electron multiplier supplies.  This blog post will explain how AugerScan automatically sets the electron multiplier voltage when acquiring data.

On Auger Electron Spectrometer (AES) systems there are two modes of signal collection.  V/F (voltage to frequency) is the analog detection mode and is used for electron beam currents of 100 nA or more. The model 96A (or 96B) V/F preamplifier converts the current that flows through the electron multiplier into a voltage which is then converted to a frequency so that the computer interface can read in the signal.  Zero to 500 nA of current through the electron multiplier corresponds to zero to 1 M cps of signal. V/F preamps were developed back in the early 80s when high resolution A/Ds (analog to digital) converters were very expensive and V/F preamps were a lower cost alternative.  V/F preamps also replaced lock-in recorder preamplifiers which were used on the very early AES spectrometers.

The other AES detection mode is pulse count (PC).   In pulse count mode an amplifier discriminator is used to count low currents (think of it as counting individual electrons).  Pulse count mode is used with electron beam currents of 100 nA or less. 

XPS systems are always operated in some type of pulse count mode – single channel, position sensitive detector or multi-channel detector. The detector currents are much lower in XPS than in AES.

Auto EMS is the AugerScan software feature that controls the electron multiplier voltage.  The first step in setting up the Auto EMS is to determine the electron multiplier plateau voltage.  The plateau voltage sets the upper limit that the electron multiplier will be set to.

 For a given current electron current, as voltage is applied to an electron multiplier more electrons are generated and counted by the detector.  More electron multiplier voltage translates into more counts until the multiplier gets into a mode where more electron multiplier voltage does not generate more electrons, it flat-lines.   That region is called the electron multiplier plateau.   The plateau region can span several hundred volts and only when the multiplier voltage is increased further do the counts start coming up again.  The higher count rate at very high multiplier voltages is saturation and you do not want to operate the multiplier in this range as the electron enriched material in the multiplier can become depleted very quickly.  The correct setting for pulse count mode would be about 50 to 100V past the knee where the signal has plateaued.

The figure below shows an AES multiplier plateau voltage of 1700V.

Before you acquire an AES gain curve you must first set the target current to 10nA.

Also make sure that your V/F preamp model (96, 96A/B, VF4) is selected in the AES Hardware Properties dialog box and then press the Preamp Defaults button in the AES Multiplier Properties dialog box. The V/F set points values are different depending on your systems V/F preamp.  The very old 96 V/F preamp has a maximum count rate of 100 k cps, the 96A/B has a maximum count rate of 1 M cps and the V/F4 has a maximum count rate of 4 M cps.

Next, open the AES Multiplier Properties dialog box and check the Auto EMS box and the Pulse Count Input box.

Press the Acquire Gain Curve button and a message will pop up to confirm that you have the beam current set to 10nA –

Press the Yes button and then the EMS gain curve will acquire and display the counts vs. voltage.  The cursor will display what it thinks is the correct multiplier plateau (Pulse Count) voltage value.  You can change it a little bit if desired, but it should be about 50 to 100V past the knee where the counts plateau.  

Press the OK button and the Pulse Count Settings voltage will be set.    The Pulse Count Settings voltage will be the upper limit of the electron multiplier voltage.

Let’s look at the logic for how AugerScan sets the AES electron multiplier voltage in a Survey.  The V/F setpoint for surveys is typically set to 800 K cps which is also 80% of the maximum 1 M cps for a 96A/B V/F preamp.

AES surveys are typically acquired starting at 30 eV and ending at 1030 or 2030 eV depending on where the Auger peaks of interest are.  For this example, we will use a 30 to 1030eV survey.

The background in AES rises as a function of the kinetic energy as shown by the red line.  The higher the eV, the higher the counts. This means that the highest kinetic energy is typically also the highest count in the survey. However, in some cases (as in the survey below) there can be an auger peak that is near the end of the survey which has a higher count rate than the very end of the survey.   For this reason, the survey V/F setpoint is set to 80% of the maximum counts in the V/F mode.  Otherwise, the electron multiplier would saturate if there is a large peak near the end of the survey. Saturation presents itself as a straight line at the top of the survey.

The logic for setting the multiplier voltage for a survey is as follows –

  1. Set the analyzer auger energy to the end of the range (1030 eV in this case).
  2. Start ramping up the electron multiplier voltage while monitoring the count rate. The starting voltage, volts per step and time per step are the values in the Multiplier Properties dialog box. In this case the starting voltage is 500, the volts per step is 5 and the time per step is 25ms.
  3. If the count rate gets to 80% of the maximum V/F value (800 K cps for the 96A/B V/F preamp) then that multiplier voltage is set and used for the survey and the input is set to VF1.
  4. However, if the multiplier voltage reaches the Pulse Count Settings voltage (1700) before the count rate reaches 800 K cps, then the pulse count input is selected, and the electron multiplier voltage is set to 1700 volts.

To summarize the logic – If there is a lot of signal the multiplier voltage will be lower, and the detection mode will be V/F.  If the amount of signal is lower, then the multiplier voltage will be higher.  But when the multiplier voltage reaches the Pulse Count Settings voltage value, then the multiplier voltage will be set to the Pulse Count Settings value and the detection mode will be PC1 (amplifier discriminator).

For AES multiplexes and depth profiles, the center of the highest kinetic element being acquired is used for the V/F setpoint.  The V/F setpoint values for multiplexes and depth profiles are lower than in surveys.  For depth profiles there needs to be more room for the counts to come up without saturating the electron multiplier because counts for some elements will increase as the sample is sputtered. 

For an elastic peak alignment, the beginning of the sweep is used for the analyzer energy since there are essentially no counts after the elastic peak.  The elastic peak (alignment) setpoint value is typically 30% (300 K cps for the 96A/B) of the max V/F counts.  If your elastic peak clips, lower the alignment setpoint to 20%.  

The electron multiplier logic is only applied to AES.    For XPS, the multiplier is always set to the pulse count (plateau) value.

To run an XPS gain curve, turn on the X-ray source to the power that you normally run at (typically 300 watts) and select an analyzer energy of 500.  The pass energy can be set from 50 to 100eV.  The input is set in the Hardware Properties dialog box.   Double pass CMAs are set to PC1, 5100 XPS systems are set to PC1, 5400 XPS systems are set to PSD, and 5600 to 5800 XPS systems are set to MCD.

Acquire the gain curve and AugerScan will automatically set the multiplier voltage to the plateau voltage to about 100V past the knee.  Sometimes if the counts are too high or too low AugerScan may not pick the correct voltage in which case you can move the cursor to the correct value and then set the Multiplier voltage by pressing the OK button.

For all XPS acquisitions the electron multiplier is set to the plateau voltage which is entered in the Multiplier section of the XPS Multiplier Properties Dialog box as shown above.   There is no input selection logic for XPS acquisitions, the input is always set to pulse count (single channel), PSD (position sensitive detector) or MCD (multichannel detector) input depending on the specific XPS detector that your XPS analyzer has.

AES input tips –

In the older PHI 10-150 AES analyzers there is no PC (pulse count) output, only a V/F output.  When there is no PC output on a CMA then the Pulse Count Settings voltage needs to be set higher than the Max V voltage in the AES Multiplier Properties dialog box.  Since the multiplier voltage will not be set higher than the Pulse Count Settings voltage, the input will always be V/F.

In the Multiplier Dialog box below the max voltage (Max V) is set to 2000, and the Pulse Count Settings voltage is set to 2100.  So, the multiplier voltage will not go past 2000 V and never reach the Pulse Count Settings value.  Since the input is set to V/F1 in the AES Hardware Properties dialog box, the input will stay in V/F mode.  The electron multiplier voltage will still be set to the V/F setpoint value automatically for any acquisition type.

For the Auto EMS to work, the AES Hardware Properties Input must be set to V/F (typically V/F1).  Then the electron multiplier voltage logic will select the input based on the amount of signal.   If the input is set to PC (typically PC1) in the AES Hardware Properties dialog box, then the input will be set to PC and the electron multiplier voltage is set to the Pulse Count Settings value. In that case the electron multiplier voltage is not ramped up to the V/F Setpoints value, it is set to the Pulse Count Settings voltage.  You normally would not want to force the input to PC on an AES analyzer as if the target current is high the electron multiplier could be damaged.

If the Auto EMS box is not checked, then the input is set to whatever is specified in the AES Hardware Properties dialog box and the voltage is set to the Pulse Count Settings value in the AES Multiplier Properties dialog box.   On some of the oldest AES systems the electron multiplier supply is the model 20-075 and the multiplier voltage is set manually. If you have a 20-075 electron multiplier supply, then the Auto EMS must not be checked. 

Auto EMS vs. manual setting of the electron multiplier voltage –

If you have a 32-100 electron multiplier supply, for the Auto EMS logic to work the mode switch must be set to Digital.   You can also control the electron multiplier voltage manually by setting the mode to Analog.   Uncheck the Auto EMS box in the AES Multiplier Properties dialog box and set the input to V/F1 or PC1 in the AES Hardware Properties dialog box depending on whether you are acquiring AES or XPS data.

0 to 10 turns CW on the Analog multiplier knob translates into 0 to 4,000V of electron multiplier voltage, or 400 volts per turn.   Elastic peaks usually need about 1000 volts or 2.5 turns on the CMA analog multiplier potentiometer, and surveys typically need 1200 to 1600 volts or 3 to 4 turns.  When operating the 32-100 in the manual mode, make sure to turn the Mode switch to OFF when not acquiring data.

AVC Auto Valve Controller Theory and Operation

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The AVC (Auto Valve Controller) was developed by PHI (Physical Electronics) in the early 1980s and first appeared on the 5000 series XPS systems. It allowed for automaton of the opening and closing of vacuum valves on the chamber for functions such as loading samples or differentially pumping the ion gun. 

The AVC comprises an electronic controller, which drives the pneumatic valves on the vacuum chamber, and a remote box, which provides a way to send requests to the controller and displays the status of the valves on the chamber.

The AVC remote box has 4 buttons:

BACKFILL INTRO

PUMP INTRO

INTRO SAMPLE

DIFF PUMP ION GUN

There are two square buttons on the front of the AVC controller:

ROUGH CHAMBER

BACK FILL CHAMBER

There is a toggle switch on the front of the AVC controller – Auto and Manual. When in the Auto mode, the AVC remote box is used to open and close valves. When in the Manual mode, the little round push button switches on the front of the AVC controller (1 through 8) are active. When you press on any of those buttons the corresponding valve will open. Pressing the button again will close the valve.

The valves on the vacuum chamber are pneumatic right-angle valves and gate valves. The V1 gate valve needs air to open and air to close, most of the other valves need air to open and are spring-loaded closed.

The valve numbers and functions are:

V1 – Gate Valve.  Isolates the main vacuum chamber from the load lock.

V2 – Vent valve.  Provides 3 PSI of dry nitrogen to the load lock.

V3 – Load lock isolation valve.  Isolates the turbo pump from the load lock.

V4 – Differential Pump valve.  Isolates the ion gun differential port from the turbo pump.

V5 – Vent valve.  Isolates 3 PSI of dry nitrogen from the turbo pump.

V6 – Pre pump valve.  Used to pre-pump the load lock

V7 – Pre pump valve. Used to isolate the roughing pump from the turbo pump.

Note that not all systems have the pre pump option and so you may not have V6 and V7.  The AVC remote has a schematic that indicates how your system is equipped.

Connections to the back of the AVC controller:

J1   TC1 – Connects to a Hastings DV6M gauge tube that is located on the load lock.

J2   TC2 – Connects to a Hastings DV6M gauge tube that is located on the turbo pump. 

J3   Probe – Connects to load lock probe position sensor

J4   Ion – Connects to ion gun remote, normally not used

J5   DIG – Connects to setpoint 2 on the DIGIII ion gauge setpoint relay

J6   Status – not used

J7   208VAC input line voltage

J8   40 pin connector to AVC remote

J9   Up to air – connects to turbo pump controller, lets the AVC know that the turbo pump is ON

J10   Solenoid power – connects to solenoid manifold

J11   Cold Cathode gauge used only on LS systems

Operation

There are two modes of operation, AUTO (automatic) and MAN (manual).  The mode switch on the front of the AVC controller sets the mode.

In the Automatic mode the microprocessor in the AVC makes sure that valves open in the correct sequence. For example, the AVC will not open the V1 gate valve to load a sample unless the load lock has been pumped out first.

When operating in the Manual mode the valves will open when the buttons on the front of the AVC controller are pressed. The valves will close when the buttons are pressed again. When operating in the Manual mode, you need to be very careful which valves you open as it is possible to dump the chamber (bring it up to air very quickly) and damage internal components such as filaments and electron multipliers.

Automatic Mode of Operation

Toggle the mode switch on the AVC controller to AUTO.

Load a sample mount:

  1. If your nitrogen is connected to a bottle, make sure that the valve to the nitrogen bottle is open.
  2. Press the BACKFILL INTRO on the AVC remote. V3 will close if not already closed and V2 will open.
  3. Rotate the cap on the load lock so that when the load lock is backfilled with nitrogen to 3 PSI the cap will be able to be easily removed. Sometimes the cap will pop off or flutter from the nitrogen pressure.
  4. Once the load lock is up to air, remove the intro cap then dock the sample mount to the intro arm. Most intro arm probes are magnetic, some of the older systems have a probe that slides between two Teflon seals.
  5. Pull the intro arm all the way back and the sensor switch will close. That will let the AVC know that the probe is in position.
  6. Place the cap back on the load lock but do not twist it tight or you will build up some pressure (3PSI) in the load lock. You can twist the cap tight after the load lock starts to pump out.
  7. Press the PUMP INTRO button on the AVC remote. V2 will close and V3 will open. The turbo pump will spin down and then come back up to speed. If your system is equipped with a Pre-Pump option, then V6 will open and V7 will close. After about 30 seconds V6 will close and then V3 and V7 will open.
    As the vacuum improves in the load lock, the bars on the AVC remote box will increase from one to four. After four bars, the fifth bar will come up after 2 minutes. Once you have 5 bars the sample will be able to be loaded into the main chamber. But keep in mind that the longer you pump out, the less water vapor will be introduced as well. I typically recommend 5 bars plus 5 minutes as the minimum amount of time to pump down the load lock before introducing the sample.
  8. Press the INTRO SAMPLE button on the AVC remote box. V3 will close and V1 will open. There will be a pressure burst and then the main chamber should drop into the low 10-7 Torr to the low 10-8 Torr range, depending on how long you pumped the load lock and how gassy your sample is. The longer you pump the intro, the lower the pressure burst.
  9. Push the load lock arm in and dock the sample mount to the specimen stage and then retract the intro arm fully. Once the intro arm is all the way out, then V1 will close automatically.     

Retrieve a sample mount:

  1. Make sure that the intro arm is all the way back and that the cap is on the load lock.
  2. If V3 is not already open, press PUMP INTRO on the AVC remote and V3 will open automatically.
  3. Wait until you have 5 bars on the AVC remote box, plus a minimum of 5 minutes. For best results you should always be pumping the load lock when not loading samples or differentially pumping the ion gun. 
  4. Press the INTRO SAMPLE button on the AVC remote. V3 will close and V1 will open. There will be a pressure burst and then the main chamber should drop into the low 10-7 Torr to the low 10-8 Torr range, depending on how long you pumped the load lock and how gassy your sample is. The longer you pump the intro, the lower the pressure burst.
  5. Push the load lock arm in and dock to the specimen stage. Lower the specimen stage down and then retract the load lock arm fully. V1 will close automatically.

Differentially pump the ion gun

  1. Make sure that the turbo pump is on and up to full speed. Some systems have two turbo pumps, one for the intro/load lock and one for the ion gun. If your system has two turbo pumps, make sure that the ion gun turbo pump is on and up to full speed.
  2. Press the DIFF PUMP ION GUN button on the AVC remote. V4 will open and the ion gun will be differentially pumped. You can now set the emission current on the ion gun and open the argon leak valve.

Back fill the chamber

  1. Make sure that the mode switch on the front of the AVC controller is set to AUTO.
  2. Make sure that the card rack power and all electron, ion and x-ray related power supplies are OFF.
  3. Turn off the ion gauge (on most PHI systems that is a DIGIII).
  4. Turn off the Boostivac or DIGITEL 500 ion pump control.
  5. The turbo pump(s) should be ON.  This is to prevent the possibility of back-streaming of oil into the chamber.
  6. Press the BACKFILL CHAMBER button.   V1 and V2 will open (V3 and V4 will be closed) and the chamber will backfill with dry nitrogen.
  7. Once the chamber has been backfilled (load lock cap can be removed) then you can turn off the turbo pump (s).

Rough the chamber

  1. Make sure that the mode switch on the front of the AVC controller is set to AUTO. The turbo pump(s) should be OFF.
  2. Make sure that all flanges are sealed and that the intro load lock cap is mounted.
  3. Press the ROUGH CHAMBER button on the front of the AVC controller.  It will light up red.
  4. Turn on the turbo pump(s).
  5. V2 will close and V1, V3, and V4 will open automatically. The system should pump out to 5 bars on the AVC remote box in about 20 minutes. Continue pumping for another 10 to 20 minutes and then turn on the DIGIII ion gauge controller. You will need to outgas the TSP filaments and wait until you get into the low 10-5 Torr before starting the ion pumps. Once the ion pumps start (vacuum is in the 10-6 Torr and improving), you can press ROUGH CHAMBER button on the AVC controller one more time and all of the valves will close.
  6. The system will need to be baked out.

Manual mode of operation

The mode switch on the AVC controller must be set to MAN.

In the AUTO mode the AVC controller uses logic to make sure that valves are opened and closed in the correct sequence.  When in the MAN mode, YOU are the logic and you open and close the valves.

Use extreme care when operating the AVC in the manual mode as it is possible to damage the system.

For example, let’s say that you have the load lock up to air and the intro cap is also not mounted on the load lock. All the filaments and high voltages for the controllers are ON.  You then manually open V1. What would the result be?  The answer – catastrophic failure! You would lose all filaments, probably the electron multipliers, and most likely crack some viewports.  So be very careful when operating in the manual mode!

In the manual mode of operation, when you press any of the 1 through 8 buttons on the front of the AVC controller, the corresponding valve will open, except for the vent valve V5. V5 opens and closes automatically when the turbo pump is turned on. If your system is equipped with two turbo pumps, then the V5 vent valve is controlled by the ion gun differential pump turbo.

Here are some examples of when you might want to operate the AVC controller in the manual mode

  • The DIFF PUMP V4 valve does not open. In this case you can manually press V4 if you know the turbo pump is up to speed. If you have just one turbo pump on your system, then you also need to make sure that V3 is closed before you open V4. After you are done sputtering, you would then need to close V4 before you do something like pump out the load lock.
  • Roughing the chamber out. You may want to manually open V1 and V3 to pump out the chamber.
  • Venting the chamber.  You may want to manually open V1 and V2.

Finally, here are links to some other blog posts that are related to the AVC –

80-365 analyzer control notes

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This blog post is a compilation of notes which are helpful when troubleshooting or calibrating the 80-365 (and 80-366) SCA analyzer control.

The 80-365 SCA analyzer control provides all of the voltages to the SCA (spherical capacitive analyzer) used on older PHI XPS (X-ray photoelectron spectroscopy) systems. Those include the retard voltage, the pass energy, the lens voltages and the electron multiplier voltage.

To troubleshoot or calibrate the 80-365, follow the calibration procedure in the 80-365 manual. Note that high voltages are present on the 80-365 boards, always refer these types of measurements to technicians who have been properly trained in working with high voltage!

If are unable to repair the 80-365 yourself, please contact RBD Instruments and we can repair the boards for you.

80-365/66 Lens Board DAC bit test

To test individual bits:  Write out on DR11 A CSR 1   

Note:   Write the low order byte out first, then the high order byte. If you get out of sequence you need to turn off the card rack power to reset the board and start over.

Lens 2

Measure from the left side of R62 to the right side of R94/G4

BitLow byteHigh byteDAC voltage
0160016000.0000
1160216000.0012
2160416000.0024
3160616000.0049
4161016000.0098
5162016000.0195
6164016000.0391
7168016000.0781
8160016010.1563
9160016020.3125
10160016040.6250
11160016081.250
12160016102.500
13160016205.00
1416FF163F10.00

Lens 3

Measure from the right side of R70 to the right side of R94/G4

BitLow byteHigh byteDAC voltage
0180018000.0000
1180218000.0012
2180418000.0024
3180618000.0049
4181018000.0098
5182018000.0195
6184018000.0391
7188018000.0781
8180018010.1563
9180018020.3125
10180018040.6250
11180018081.250
12180018102.500
13180018205.00
1418FF183F10.00

80-365 Lens board calibration notes

For XPS and AES, the output voltages are positive, and the fine supplies are negative.  Make sure that you set the polarity before programming on dual polarity boards.

1310 is + polarity for L3

1320 is + polarity for L2

Common data values

L2            Output C53/G5                  Fine Supply    – lead ground side R143   + lead right side R142/G5

1801,1800 – Adjust R45/A3 for -20V on fine supply

1800, 1808 – Adjust R77/B4 for – 20V on fine supply           Adjust R67/G3 for +409.6V on C53

18D4, 1830 – Adjust R67/G3 for +2500.0 V on C 53 output.  Readjust R77/B4 for -20V on fine supply

1800, 1800 – zero

L3            Output C41/E5                   Fine supply         – lead ground side R127/E5  + lead left side R120/E5

1601, 1600 – Adjust R52/C3 for -20V on fine supply

1600,1608 – Adjust R87/D4 for–20V on fine supply      Adjust R59/E3 for +409.6V on C41

16D4, 1630 – Adjust R59/E3 for +2500.0V on C 41 output. Readjust R87/D4 for -20V on fine supply

1600,1600 – Zero

NOTE:    If you have issues with the +5V supply dropping and voltages not loading properly, look at the local power supply board.  You may need to replace the 3524 regulator on the local power supply board.

80-365/66 Pass Energy board DAC bit test

To test individual bits:

Pass energy range = is 0 to 10V on the DAC = 1920 or 2145 depending on the model number of your analyzer control.

Write out on DR11 A CSR 1   

Note:  Write the low order byte out first, then the high order byte. If you get out of sequence you need to turn off the card rack power to reset the board and start over.

To set the DAC back to zero between bits, write out 1a00 twice

The following table shows the voltage on the DAC measured from TP24 / C2 to TP24B /C2  

0000 0000 0000 0001

bit 0

0.022 V

1a01, 1a00 = .0001525 V on the DAC

0000 00000000 0010

bit 1

.044 V

1a02, 1a00 = .0003052 V on DAC

00000 0000 000 0100

bit 2

.088 V

1a04, 1a00 = .000 6V on DAC

0000 0000 0000 1000

bit 3

.019 V

1a08, 1a00 = .00122 V on DAC

0000 0000 0001 0000

bit 4

0.35 V

1a10, 1a00 = .00244 V on DAC

0000 0000 0010 0000

bit 5

0.7 V

1a20, 1a00 =.00488 V on DAC

0000 0000 0100 0000

bit 6

1.4 V

1a40, 1a00 = .0097 V on DAC

0000 0000 1000 0000

bit 7

2.8 V

1a80, 1a00 =.019 V on DAC

0000 0001 0000 0000

bit 8

5.63 V

1a00, 1a01  =.039 V on DAC

0000 0010 0000 0000

bit 9

11.25 V

1a00 ,1a02  = .078 V on DAC

0000 0100 0000 0000

bit 10

22.5 V

1a00 ,1a04  = .156 V on DAC

0000 1000 0000 0000

bit 11

45 V

1a00 ,1a08   = .3125 V on DAC

0001 0000 0000 0000

bit 12

90.02 V

1a00 ,1a10  = .625 V on DAC

0010 0000 0000 0000

bit 13

180.03 V

1a00,1a20   =1.25 V on DAC

0100 0000 0000 0000

bit 14

360.06 V

1a00 ,1a40   = 2.5 V on DAC

1000 0000 0000 0000

bit 15

720.13 V

1a00 ,1a80  = 5.0 V on DAC

All Bits:

1A00, ,1aFF   = 10 V on DAC

1920 or 2145 VDC on the output across C56

80-365 / 366 Pass energy board range note

The 80-365 and 80-366 pass energies have different maximums.

The 80-365 is 1920V

The 80-366 is 2145V

Make sure that you have the correct procedure when you calibrate the board.

Measuring the Pass Energy output voltages

There are some scale factors involved when measuring the pass energy voltages.   

If you are measuring the pass energy voltage across C56 on the pass energy board, the scale factor is approximately X 1.34.  For example, if you set the pass energy to 187.85, the output voltage across C56 is 187.85 X 1.34 = 251.8 VDC.   You can calculate any pass energy actual voltage value by multiplying the pass energy in the software (set up an alignment or survey) by 1.34.

If you are measuring the test points in the filter box, the scale factor is to divide by 1.7.    For example, a pass energy of 187.5 divided by 1.7 = 110.3 VDC.  If you set up the pass energy to 187.5 in the software, you will see approximately 110.3 VDC between the IC and OC test points in the filter box. The resistors in the filter box divide the voltages so that they are correct on the IC, OC and MR contacts in the analyzer.

To summarize –

C56 output on pass energy board = Pass Energy X 1.34

Test points in filter box = Pass Energy divided by 1.7

80-365 Local Power supply board notes

Capacitor Voltage Comments
C33 22V +/1 1.5V   adjust R27 Transformer output before regulator
C35 +15 Pass energy board power
C36 -15 Pass energy board power
C34 +5V Pass energy board power
     
C9 22V +/1 1.5V  adjust R3 Transformer output before regulator
C10 +15 Lens board power
C7 -15V Lens board power
C12 +5V Lens board power
     
CR35 cathode to CR36 anode +225V Pass energy board power
CR 37 anode to CR36 anode -225V Pass energy board power
     
CR17 cathode to CR17 anode +150V
CR18 anode to CR17 anode -150
 

TIP: If the voltages are low when the pass energy or lens boards are installed, most likely the issue is a weak 3524 regulator. Replace it with a new SG3524N

80-365 Retard supply bytes

bitlow byte (hex) hi byte (hex)DAC V
0110012000
1110112000.00015259
2110212000.00030518
3110412000.00061035
4110812000.0012207
5111012000.00244141
6112012000.00488281
7114012000.00976563
8118012000.01953125
9110012010.0390625
10110012020.078125
11110012040.15625
12110012080.3125
13110012100.625
14110012201.25
15110012402.5
16110012805
All11FF12FF10