Hi Robert,


When you checked for continuity on pins 1 and 10, did you disconnect the
leads emerging from the Teflon 'housing' first?

Leads 1 and 10 need to be disconnected since otherwise the measuring current
from the multi-meter will travel back to the source control board.

If you got continuity (or resistance) across 1 and 10 even with the leads
off, you would need to take the source out and have a look at the filament
first before thinking about the source board being the problem (exchange
price in the UK >£2k). The filament wire might not be burned through yet to
fail the multi-meter test but in too bad a shape / condition to generate a
reasonable amount of electrons to register in the trap.


Regards,

Wolfram


> -----Original Message-----
> From: Stable Isotope Geochemistry 
> [mailto:[log in to unmask]] On Behalf Of Geldern, Robert van
> Sent: 01 August 2006 11:18
> To: [log in to unmask]
> Subject: Emission problems on XP
> 
> 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]
>