noise on FID when connect second detector-HP5890

[dlorenzo]

Dear friends: we work on the University and have a 5890 GC, with a FID detector.
Few months ago, we've build a second detector (electroantennogram) and connected it to our system. Since we connected the power contacts (heater and PT-100) we are having randomic noise in our FID signal (negative peaks, etc). We are not using the signal of the 2nd detector yet, so maybe some interference between the power cables and the FID' signal ones. We were carefully avoiding crossing between power and signal cables, so what's happening?
Does anyone have an idea?

Thank you in advance. Sincerely yours

DL

[Ron]

I've seen this problem in the past. The problem is noise from the heater being picked up by the signal cable of the FID. Try wrapping all the cables in aluminum foil to minimize the interference.

[dlorenzo]

Thanks Bob, I'll try that.
regards

DL

[dlorenzo]

The detector's body and the chasis must be isolted because of grown problems, that's all!
Thanks anyway