A bit of background about myself first and then the problem. I have been a GCMS analyst performing all maintenance and repairs of the systems I run since 1992. I have worked on 5970s through 5977s as well as all major manufacturers GC and GCMS systems. I state this for everyone to realize I am not a novice but that does not mean I haven't overlooked something that might be simple.

I have a client with two different 5977s that are now reporting RFPA errors consistently. They started out as being intermittent issues. Sources have been thoroughly cleaned, new columns, inlet maintenance etc. Routine samples which have been run for years on these systems and previously on 5973 and 5975 systems without issue.

Diagnostically dipping the quads is now showing instability for higher end m/z ions (above 500). Stable readings for 10 m/z (around 5-10mv) and 100 m/z (adjusted to be between 70-100mv but stable once adjusted). Reading at high-end are either very low 5mv or they start a given value and then climb to above 1500mv and then drop off to 5-10mv.

If you run a manual scan and set the range to less than the maximum (is 10-500 as opposed to 10-1050) you see at the upper m/z range high readings for every given m/z. If the range is set higher you get the RFPA Error. Cleaning quads helps for a short period (if anyone had a good known to work quad cleaning procedure would love to hear it) but then the error returns and at the high cost it is not worth it to send out. (The company that cleans them is quite reputable and I highly recommend them for board repairs).

Any questions comments or thoughts greatly appreciated

Additionally if anyone knows how to get in touch with Jeff Hollis with AnalySense please let me know.