My Delta-S has suddenly lost 90% of it's sensitivity. Everything else seems to be normal. The closed and open vacuums are normal, the peaks are small but the peak shape and ratio are normal. I tried to tune the Delta-S and could increase the signal a small amount. I have not changed the filament in 8 years, wonder if this could be the problem.
UWM-school of Freshwater Sciences
600 E. Greenfield Ave.
Milwaukee, WI 53204
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