# Channeltron contamination/cleaning

I have some channeltrons placed in a close-to-UHV environment (~10^-8 torr) where I suspect contamination.
The chamber in which the channeltrons are placed was previously part of an oil contamination accident but has been cleaned. However the channeltrons were placed inside the chamber after the contamination but before it was discovered.

I'm wondering if someone knows

1. how one can know if that is the problem (how does it show on i.e. the signal)

2. if 1, how to clean the channeltron if possible (found something about isopropyl and 150C baking)

thanx