Loma IQ2 Service Manual page 96

REACTIVE AND RESISTIVE "X" & "R" CHANNELS
Your detector converts the change in balance caused by either product or metal
into two distinct signals called Reactive and Resistive signals, this technique is
known as phase detection.
The correct setting of these channels can be quite simply checked by the user,
however in the unlikely event of the settings being incorrect there is no user
adjustment available. If the detector is of a dual frequency type then this check
will require repeating for both operating frequencies. If any problems are
encountered and cannot be resolved please call your local Group Service
Centre.
Poor metal sensitivity or unexpected product effect changes may be a symptom
of phase integrity.
NOTE
No metal or product should be present in the aperture whilst this check is in
progress.
Checking Phase Integrity and Channel Noise (single & dual frequency detectors)
1. Using the 5mm allen key supplied with your equipment, unscrew the 2
front hinged door screws on the control box and open the door.
2. Select an unused product memory position and set the "Head power" to
"MAX".
3. If the detector is a dual frequency type then initially select HIGH for the
frequency menu position in the product memory chosen.
4. It is advisable to check the "Balance" value is within specification before
checking, an excessive out of balance signal can effect the phase
integrity.
5. Connect the oscilloscope via a x1 probe to TP9 "X" channel (or use the
white wire connection pin on PL1) shown in
earth clip to the adjacent control board mounting hex pillar.
Module 9095
Functional Testing
Figure 3, connect the probe
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