Emission current flickering on and off

[dawsonjz]

I recently cleaned the source on a 5975C source, changing both filaments, and after reconnecting the source and turning on the mass spec, there was a "No emission current" message in the Tune and Vacuum control. After letting the instrument sit for a little bit and restarting the computer, I checked the tune and vacuum control again and the message was no longer present.
I performed an S tune to check if it was working properly and during the tune, I noticed at multiple times, it flashed "No emission current" and then the mass spec would turn back on. The tune did complete and looked pretty good.
I ran a blank on a nine minute method and everything looked good. I then ran a blank on a general screen which lasts 19.83 minutes and at multiple times, there was an error saying the mass spec had turned off, creating inverse peaks on my chromatogram.

Has anyone had this problem where their filaments seem to flicker on and off? I checked the connections to the filaments and everything seems to be connected properly. This MS also had its ceramic sideboard recently replaced due to a connection falling off, so everything should (theoretically) be good on that end. Is there any possible fixes to this problem?

[Rndirk]

Did you try the other filament yet?

Sounds like a problem with the filament itself or with the connection.

[James_Ball]

Definitely try the other filament if you haven't already. If it works then possibly you got a bad filament, if not then there will be other things to try.

[PhysisGC]

Did you end up fixing this problem?

I am having a flickering filament in my 5977A now. My flickering is a bit different though; its more like a light bulb where it doesnt go all the way out, but clearly the current through the filament is inconsistent. I have tried both filaments and they both do the same thing.

We recently had a main board replaced in that instrument so I'm wondering if the Agilent rep didnt installed it properly.

Any one else have any ideas?