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Prior to contacting Amptek, please follow our troubleshooting instructions below and consult the additional troubleshooting documents.

Please have the model and serial numbers of your Amptek device(s) available when contacting Amptek for technical support.

Email (sales and technical support):

  • Troubleshooting Instructions +

    Digital Processor Products (DP4, DP5, DP5G, PX4, PX5, X-123 (all versions), Gamma-Rad, Gamma-Rad5, TB-5, MCA8000D)

    1. Sometimes no spectrum (or a distorted spectrum) will appear if the fast and slow thresholds are not set properly. Remove any source from in front of the detector and click the “Tune Slow/Fast Thresholds” button on the toolbar. Put the source back and check if the spectrum appears. The input counts should always exceed the counts. If the auto tune fails, or if the counts exceed the input counts, perform the manual adjustment in the next step
    2. The Fast and Slow Thresholds can be adjusted manually. First turn off pile-up rejection (DPP Properties->Shaping tab). Then click the cursor to channel 1 and press F8. This will set the Slow Threshold (LLD) to channel 1. This will show the noise of the system. Click the cursor just to the right of the noise and then press F8. Press the “A” key to clear. There should be no counts accumulating in the spectrum display. Now put the device into “Delta” mode by clicking the Delta button on the toolbar. Open the DPP Properties and go to the Shaping page. Adjust the Fast Threshold until 1 to 15 counts per second appear in the Input Counts in the right-hand Info Panel. Now turn on PUR and click OK. Click the Delta button to get back to normal MCA mode and put the source back in front of the detector. The Input Counts should slightly exceed the Counts
    3. In the DPP Properties->Gain tab, use the default input offset option
    4. Check the High Voltage (HV) of the unit. For Amptek Si-PIN and CdTe detectors the HV polarity must be positive (and the input polarity negative in the DPP). For SDD detectors the HV polarity must be negative (and the input polarity positive in the DPP).
    5. If you still have problems, please email Amptek a saved .mca file and the diagnostic data from the DPPMCA software (see below for instructions)


    • If you are having software issues, including Windows 7/8/10 issues with USB adapters, please see the MCA8000A software download page.
    • Connect to the device and go to the Acquisition Setup. Click on the defaults button and try the acquisition again. If this does not allow a spectrum to be acquired then go to the file menu and select save and email the .mca file to Amptek.
  • Description +

    If you have one of the following products, please use the Amptek DPPMCA (FW6 products) or ADMCA (FW4/FW5 legacy products) to acquire a spectrum and send a saved .mca file to Amptek:

    • X-123 (all versions)
    • DP4 & PX4
    • DP5, DP5G and PX5
    • Gamma-Rad & Gamma-Rad5
    • TB-5
    • MCA-8000D (including Option PA)
    • MCA-8000A (including Option PA)
    1. Make sure you are using the latest version of the DPPMCA software.
    2. Power on your device in accordance with its instructions
    3. Connect your device with your PC, and connect with the software
    4. Click “Help”, then “About DPPMCA”.
    5. Click the “Request Diagnostics ” button. Diagnostic data will be dumped into the box; this includes a hex dump of the configuration memory. Select all these values, copy them (Ctrl-C), and save them in a text file. Notepad is a convenient editor.
    6. Click “OK” and close out of “About”.
    7. Acquire a spectrum for approximately 30 seconds; if there is no spectrum displayed, still save the file as it will contain important information about the system that will help Amptek troubleshoot the problem
    8. Go to the File menu and select Save As to save the .mca file.
    9. Email both the .mca file and the diagnostic text file to
    10. Do not send screen shots of the software. Only the .mca file and diagnostic data are needed.
  • Additional Troubleshooting Documents +