I have heard that when detecting around other detectors the F70 and F75 are prone to EMI. IF so how do you control it with sensitivity or threshold adjustments.

Control it FIRST....... with F1 - F7 freq shift function. THEN....... try raising Disc to '5'. THEN.... drop Sens. In that order. I believe I covered this in COMPILATION #1 and COMPILATION #2...... and may have mentioned it in Rcpt Ack of F75 LTD Proto.