JVC GR-DVF11U Manual page 97

Adjusting the Digital Video Cassette Camera with JVC Service Support System Software
If the error rate exceeds the maximum allowable values, the head and tape
transport system should be cleaned.
If the error rate still exceeds the maximum allowable values, you should
consider that the head may have failed or the preamp shield is loose.
Best results are obtained when the camera is fully assembled prior to starting
the adjustment.
Strong radiation in close proximity to the camera such as a computer or video
monitor will affect the error rate reading. Usually giving a false higher error
rate.
This completes the VCO Center Frequency (ME Tape LP Speed) adjustment.
Conclusion
This completes the adjustments.
Select Exit from the File menu in the Service Support System window.
1.
Turn the unit off.
2.
Disconnect the cable between the unit and the computer.
3.
Remove the Jig Connector, and re-install the Jig Cover.
4.
91