uzman wrote:
8 million signal means a short circuit .
If you removed the collector and still getting this signal , you may check the spring on the detector , it should not touch any metal part of the detector.
Except the concave portion of the collector. That is the only thing the spring should touch.
Also make sure you did not forget the teflon spacer that insulates the collector from the rest of the detector housing.
If the noise suddenly began on the second instrument check your gasses for purity and for any leaks in the supply tubing. Also make sure there are no fans or air conditioner outlets blowing on the detector, those can disturb the flame and cause noise too.
You probably have good gas but just be sure it is high grade carrier, hydrogen, air and makeup gas that is being used. I once went to help a laboratory that had a problem with an ECD they said had very little sensitivity, turns out what they though was a small signal was actually peaks that were interruptions in a maxed out signal on a chart recorder (very old instrument). When I looked at their setup they were using plain industrial grade hydrogen as their carrier, and actually had a section of rubber air brake hose from an auto supply company as an extension to make their gas lines long enough to reach the instrument.
A good grade of hydrogen carrier and fresh copper tubing gave them great signal and good sensitivity.