We seem to have run into a serious design flaw with the NV1740 LCD
monitor. One of our customers has noticed (and we have re-produced the
problem in our factory) that a 455MHz RF transmission from a Motorola
CP200 handheld radio http://www.commusa.com/catalog.aspx/Motorola_CP200 is
knocking out the backlight on this monitor. The monitor must be power
cycled before the inverter starts up again. I have poked around with an
'scope on the inverter, and know that the problem is localized to the
inverter itself - the TFT controller does *not* drop the enable signal to
the backlight. I suspect that the O2 micro OZ960 chip on the inverter is
sensing an over-current situation on it's outputs and shutting down. I
looked for a data sheet for the chip on O2 micro's website in the hope
that I could adjust the over current sense circuit, but they do not offer
them without an NDA. *sigh*

Shielding, grounding etc. have so far proved fruitless.

If anyone has a schematic of the NV1740 or the Inverter inside (A Frontek
FIF1804), or even a datsheet/pinout for the oz960 inverter controller,
(hell, even a schematic of *any* inverter with this chip) I would be
extremely grateful.

Thank you.

[Remove MYBRAIN to reply by email]

Jay Walling
Diagnostic Engineer

Comark Corporation
93 West St.
Medfield, MA 02052
http://www.comarkcorp.com