I had exactly the same problem yesterday. After putting in a third filament 
the XP finally worked fine. All of the filaments I tried were electrically 
sound so I can only assume that the ones that were not working were in some 
way shorting somewhere although, just as you have done, I checked for a 
short at the board connectors and did not find any. Very weird! Oh well, at 
least taking the source in and out gave me some exercise!

Ian

--On 01 August 2006 12:18 +0200 "Geldern, Robert van" 
<[log in to unmask]> wrote:

> Greetings,
> we run a DeltaXP in dual inlet mode and are facing problems with the
> emission.
>
> *emission LED is off, Acell. Voltage LED is green when HV is switched
> on.
> *Isodat 2.0 tells me that 3.1kV are on but no signal comes from the
> cups. Box and Trap readings are zero.
> *Vaccum is perfect.
> *We checked pin 1 and 10 (cathode) at the source. The filament of the
> cathode is OK.
> *We checked for shortcuts of the cathode with ion source chamber and
> ionization box. No shortcut.
> *We measured the current in the filament while switching on the HV => it
> climbes to around 4 Ampere. So the cathode seems to work.
> *Switching on/off everything did not help (but I thought it may be worth
> to try).
>
> Any other ideas besides electronic problems on the HV board?
>
> greetings,
> Robert
>
> --
> Dr. Robert van Geldern
> Leibniz Institute for Applied Geosciences (GGA)
> S3: Geochronology and Isotopehydrology
> Stilleweg 2, 30655 Hannover, Germany
> phone: +49-(0)511-643-2313 (office), -2539 (lab)
> fax: +49-(0)511-643-3665
> mailto:[log in to unmask]



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Dr Ian D. Bull
Organic Geochemistry Unit (OGU)
Bristol Biogeochemistry Research Centre
School of Chemistry
University of Bristol
Bristol  BS8 1TS
United Kingdom

Tel.        +44 (0)117 9546967
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Email      [log in to unmask]
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"I left in love, in laughter, and in truth,
and wherever truth, love and laughter abide,
I am there in spirit."

                    - Bill Hicks (1961-1994)
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