Futaba 7CHP PPM/PCM Backlight Mod

I've been using this radio for so long from the time i got my Thunder Tiger Mini Titan 450 6ch RC heli about 4 years ago which i got it second hand from a friend. Since then it has been my primary TX for my aircraft.
  As for this couple of years, i'm active in our night flying activities which is held every Friday night at  a public field about 20 minutes drive from my house.
  The thing is, its hard to do some adjustment to my TX setting at night without a backlight on it. So i did some searching and found a way to have a backlight on my ol TX.




I've got the basic trick for this mod from here.
The EL Panel used with this mod from here. It's a 4x4" panel with a 12V DC inverter.

 

Here is the idea on how i want to connect the panel to my TX. I'm going to use a switch as I don't want the backlight to be always on as i power up the TX and yet i don't want to by accident switching the backlight on when my TX is off.

Here's the first thing to do. TAKE THE BATTERY, CRYSTAL AND ANTENNA OFF THE TX.

with a flat screw driver slowly pry out the turn button.

pry out the front panel using a smaller flat screwdriver.

take out 4 screws from the back of the TX and save it some where safe.

we need to take out the 5 screws (red) on the main board and release the LCD ribbon cable (orange) by flipping the little lock on both side (yellow) upward for the ease of the following steps.

bring out the main board and you will see the back of the LCD panel from the inside. I once try to pry out the LCD panel from the front using a flat screwdriver but the glue at the back of the panel is too strong that i'am afraid going to ruin the panel if i keep forcing it. Then i check the backside for the inside of the TX and found out there is two holes that i can use to push the panel out. But first i use a couple drops of Zippo lighter liquid which i know good for removing glue. In this case weakened the bonding. Then by using blunt side of a skewer i push the panel out slowly as not to scratch the panel.

DON'T DO WHAT I DID IN THIS PICTURE. I was suppose to peel off only the silver backing of the panel on this step. But end up peeling the dark transparent layer which used to make the character on the LCD visible as well.
So in this step be careful. There is two layers of plastic on the back of the panel and only remove the first silver layer and leave the dark one intact.

Now prepare the EL panel to be put under your LCD panel as backlight. Cut both connectors on the panel and inverter side as we gonna solder it back together later on. I opt to used the same hole for the ribbon cable.

this is where i placed the inverter in side my TX with a double side tape. Its under the PPM/PCM module. Now you can solder the two wires from the inverter to the EL panel. Mind the polarity and make sure to insulate the solder joint with heatshrinks or electrical tape.

There is a ready spare hole for a switch on my TX covered with a black tape. So i decided to used it for my backlight switch.

Refer to my previous diagram on top here is how its look like and the place to solder on the main switch and the 12V supply.

once you are done. test it and put it all together.