5975C high-energy dynode output cable not properly connected

[rbil1]

Hi members,

I have some awkward situation case. After cleaning Ion source on 5975C by service staff and puting things back to stock it seems they didnt properly fixed high-energy dynode output cable which cause signal disturbtion with delay causing noisy signal on chromatogram and altered m/z. After 4hours of system was running without knowing that anything is wrong I did tune test everything was normal even analysis of sample no column bleeding or anything nothing to be concerned about. Same as it was before cleaning and opening MS.


..then after a while in afternoon ...it suddenly lift up baseline which disturn communication GCMS. Also evolution test failed suddenly which cause HIGH mass 69 219 and 502 The whole system was then VENTED and shuted down after few hours. Therefore I went looking for cause I have opened lid of MS and find out that high-energy dynode output cable was not properly connected to connector by service staff. (photos in attachment) I have completly tightly plugged it in turn system back ON and perform pump down...Then I first did EVOLUTION TEST everything was normal also on TUNE test.

I keep running system within a night I did analysis of sample on Filament 1 baseline was normal up to about 230C @ 14min then baseline column bleed apears also tried to perform NO injection with GC ALS: disabled mode I get the same outcome column bleed.which was NOT present before system was not failed. Tried also with bakeout MS and setup oven GC to 260C. for 2hours. no change. On filament 2 noise peaks are present all time. But baseline is normal.

Is it possible that this high-energy dynode output cable cause some kind of PCA board arcing or cause column degradation or something ? Or can root case be somewhere else ? No other symtpoms are observed Tune test evolution test is OK except column bleed at 230C 14min. On MS there is 207 m/z with blank run without injection.

EM volts was high even priorly before system was collapsed. Its nearly end of life. Waiting for new replacement..

photos of baseline :

https://photobucket.com/bucket/613a9d86 ... f0c81192b7

https://photobucket.com/bucket/613a9d86 ... 074c70da37

https://photobucket.com/bucket/613a9d86 ... 5ac0315305

https://photobucket.com/bucket/613a9d86 ... d29a670d29

https://photobucket.com/bucket/613a9d86 ... c4a4d80fc9

https://photobucket.com/bucket/613a9d86 ... 2add63864e



All suggestion are welcome and highly apprechaiated.

Thank You,

All best in year 2026.

best regards

rbil1

[rbil1]

**UPDATE**

Aditionally attaching yet latest autotune @ filament 1 and 2. in case If anything helps.
Blank run analysis with GC ALS were disabled was performed as well with the following method :

START : 180C ; END : 240C

on filament 1 : No noise or random peaks up to approx. 230C then somewhat bleeding occurs each peak own 207 m/z are observed.

on filament 2 : Noise present all time showing 207 m/z ; even if i set method : START 50C starts to release peaks noise on real begning.
i getting noise peaks on start even on low temperature. which show mostly 207 m/z.

EM volts is eleveated a bit (due to weared photomultiplier) but this perhaps should not be an primary isseu. IMO. according to cause/aperance above.


https://drive.google.com/file/d/1BAmXoA ... sp=sharing (tune 2 filament)

https://drive.google.com/file/d/1AQDIuk ... drive_link (tune 1 filament)

https://drive.google.com/file/d/1qgpjeU ... drive_link (filament 2 @ blankrun)

https://drive.google.com/file/d/1uP757q ... drive_link (filament 1 @ blankrun)




best regards
rbil1

[rbil1]

https://community.agilent.com/technical ... -connected

whole experience is posted here the latest news.
thanks

best regards
rbil1