My JVC camcorder, gz-mg30u, does not show a picture when it is in record mode. The screen remains black, while still displaying recording information, and symbols.

SOURCE: jvc GZ-MG30u software and usb cable

Im sending you emails.

SOURCE: JVC GZ-MG30u software

i had the same problem and have to buy the cd at a cost of $60.00.it is available from Enfield Spares
28 Coronation Parade
Enfield NSW 2136

Ph: 02 9715 2448
Fx: 02 9715 2449

This above company is able to provide parts numbers and will supply all over the country.

SOURCE: JVC CAMCORDER GZ-HD7U

You CAN NOT use the Firewire to capture your footage like DV or HDV camcorders. I too Have a macbook pro and use FCPS2 to edit my footage. If you want to get the footage off of the HD7u, you'll have to connect via USB2.0 and download the .TOD files and use a program to convert them. I use MPEGStreamclip. It will work with the .TOD files and convert them to a format that iMovie or FInal Cut will understand. If this is not for professional work you'll probably be fine converting the footage to the HDV standard or DV standard and not have to render in FCP to edit the footage. 
Caution... MPEG2 codec may be needed. If you have FCP or have Quicktime pro, you probably already have it other wise you can purchase it from apple for $29.99 or if you try real hard (not to hard) you can probably find it on a torrent for free.
I hope this helps your situation
Ciza

SOURCE: jvc video camera

there is a repir thing with certain models see below. CCD Failure/Lens Cap Warning Error JVC has received reports that in certain circumstances, the following models may, while in the camera mode, show no picture, a distorted picture and/or display “LENS CAP” even though the lens cap is removed. We have identified the probable cause as a failure of the CCD image sensor. Repairs of units exhibiting these problems as a result of a defect in the CCD image sensor will be made free of charge at a JVC Authorised Service Centre even if the unit is outside warranty.
Please call our Consumer Support Department on 0870-330-5000 to obtain your free repair. We apologise for any inconvenience and we appreciate your understanding and support.
Please note that this offer expires on 30th June 2009 and is applicable only to failure of the CCD image sensor.
This information applies to the following models:
GR-D18, GR-D20, GR-D21, GR-D22, GR-D225, GR-D23, GR-D24, GR-D30, GR-D31, GR-D32, GR-D33, GR-D34, GR-D40, GR-D43, GR-D50, GR-D53, GR-D54, GR-D60, GR-D63, GR-D70, GR-D73, GR-DX25, GR-DX27, GR-DX28, GR-DX35, GR-DX36, GR-DX37, GR-DX45, GR-DX47, GR-DX48, GR-DX55, GR-DX57, GR-DX67, GR-DX75, GR-DX77, GR-DX78, GR-DX95, GR-DX97, GR-FX15, GR-FX16, GR-FXM39, GR-FXM393, GR-FXM40, GR-FXM404, GR-PD1, GR-SX19, GR-SX25, GR-SX26, GR-SXM29, GR-SXM30, GR-SXM49, GR-SXM50, JY-HD10.

SOURCE: JVC Camcorder Everio GZ-MG21E Driver & Software MISSING!!

hi there,

click HERE to download the driver.

pincer