Service Instructions
Changing the tune and match conditions:
The tune and match conditions of the resonator can be changed in the service mode within certain limits. This requires a service activity where the resonator is partially disassembled. Tune and match must be performed by trained persons only. A service adapter has to be used which is not part of the delivery.
- Disassembling the coil by untrained persons can damage the coil
- Wrong adjustment of the tune / match conditions can lead to a performance decrease
Step 1: Remove the combiner
Remove the coil from the magnet. Unscrew the three screws which attach the combiner with the coil structure. Pull out gently the combiner board.
Step 2: Connect the adapter cable
Unscrew the SMA connector of the two coil elements. Put the service adapter on that coil element which is to be tuned and matched; terminate the other coil element with the 50 Ohm terminator.
Identify the position of the tune and match rods inside the coil structure
Step 3: Tune and match
Insert the load for which the resonator shall be tuned into the resonator and connect the adapter cable with the T/X pin of the T/R connection socket.
Start the wobble program in ParaVision and observe the wobble curve on the acquisition display. Change the tune and match settings until best performance is obtained. Stop the wobble program and interchange the channel X1 with X2. Restart the wobble procedure for X2.
Step 4: Re-assemble the coil
Remove the adapter cables and connect the rf cable X1 with the "X1" SMA connector of the combiner, cable X2 with the "X2" SMA connector. Close the SMA connection with appropriate torque and insert the combiner into the coil housing. Fix the combiner with the three screws.
Troubleshooting
- Weak or no signal: check the correct connection of X1 and X2 on the combiner board
- Decrease in SNR: wrong tune / match settings or influence of ECG electrodes (check wiring)
