[TenTec] Omni VII LCD screen and DeOxit D5

[Marcus Florido]

Many of us have had issues with the encoders on these and likely many other rigs.  Thankfully, the ones on the Omni VII are simple mechanical encoders, and a quick spray with DeOxit D5 will normally take care of the problem pretty quickly.

Unfortunately for me, things got a little complicated when the can of DeOxit leaked out while I was spraying it.  Looking for good entry points into the "Multi" encoder for the DeOxit, I took the lids off and sprayed it into any crack/crevice I could see.  The can of DeOxit I was using has one of those flip-up straws, which leaks severely at the hinged joint.  As a result of this leak, some DeOxit managed to find its way into the LCD panel and made the screen all blotchy.  Capillary action ensured that the DeOxit distributed itself all over the inside of the panel, making the biggest mess possible.

Since DeOxit leaves a residue (this is on purpose), there is little chance that it would eventually evaporate.  This left me with no other option than to R&R the LDC panel.  Here are some take-away's:

--When removing the front panel, be very careful with the ribbon cable that connects the front panel to the board.  Try not to pull it loose from one end--it is better to slip something flat underneath and pinch the cable between your tool of choice and your finger.  Pull it out vertically.

--The LCD panel will require a complete disassembly.  There are tiny metal tabs that will need to be bent outwards in order to take it apart.  Take care with these.

--The backlight and diffusion mechanism has many layers.  Pay close attention to the order and orientation of these layers--taking pictures is not likely going to do the trick, as they are almost impossible to distinguish with the naked eye, let alone on a picture.

--One of these layers includes a half-mirror-type set of diffusers.  I believe that this is designed to reflect light from outside of the LCD back out in the direction that it came from.  If installed backwards, it will reflect light in the direction of the backlight source, and will make the screen appear somewhat dim.  If you've never seen an Omni VII screen before, it's likely that you'd never know the difference, so the change is subtle.  Pay attention so that you don't have to do the work all over again.

--The diffusers are very soft plastic and can be easily scratched by your fingers alone.  Be careful to use only very soft objects when dealing with them.  Try and blow off any dirt before you wipe.

--Keep dust contamination to a minimum by using micro-fiber cloth.  However, these may be too thick to adequately reach the glued edges between the diffusers.  TP did the trick, but left some dust, so a little canned air should probably be procured before you start the job.  (If you don't have any TP on hand, I'll be glad to talk to you over the air, but not so much in person.)

--Disassembly of this rig is pretty easy and intuitive.  Thank you Ten Tec for designing this rig so that us mere laymen can work on it.

--K4VBB