Eggfinder LCD reciever issues

[AdamK1025]

Howdy All, I am having issues getting my eggfinder lcd receiver to operate properly. when powered the buzzer makes its boot noise and the lcd screen only comes on when flipped in the opposite orientation show in the assembly guide, when the trs is transmitting the rf module starts blinking green in sync with the red light on the trs. Any and all help is appreciated.

 

[Worsaer]

Can you take pics of the receiver board, both sides, without the LCD mounted?
also, did you try adjusting the contrast potentiometer, the one with the really small philips slot?

 

[AdamK1025]

Attached are the pictures of the front and back of the pcb. Note, this board is Rev B2 and is the 70cm HAM variant. I'm uncertain why it is having this issue but when I plug the lcd in upside down the backlight turns on as shown. I have tried to mess with the potentiometer a bit but with no noticeable change.

 

[Worsaer]

Did you try adjusting the contrast?

 

[AdamK1025]

Yes I have but it didn't seem to make any text appear. Maybe Chris will stumble across this post, lol.

 

[Voyager1]

… when flipped in the opposite orientation show in the assembly guide, …

Not a good plan! When you do that you place the LCD backlight LED pins directly over the supply sockets on the main board header. That’s why the backlight is coming on like that. All the other signals will be mixed up and you might damage the processor and LCD module.

 

[Worsaer]

Yes I have but it didn't seem to make any text appear. Maybe Chris will stumble across this post, lol.

Ok. I ask because when I’ve asked others this question, they were not trying that adjustment while the receiver is powered on. When it’s on, and very slowly adjusting this screw, you should see the character positions change.I learned this the hard way on the first one I built.

 

[BLKKROW]

Flip the LCD to it's original/intended position, and try to change the contrast of the LCD screen.

 

[cerving]

Turning it around isn't going to help things... it will probably fry the LCD panel. That's why the backlight is coming on... normally it would be controlled by the two BL switch pads and powered by the 5V supply, but reversing it provides constant power from the 5V supply to the backlight. As mentioned earlier, the contrast needs to be adjusted with the power ON... it's a little touchy so you're probably not going to get it just right with the power off.

We recommend that if one of our products doesn't work after you assemble it that you consult the troubleshooting steps, then send us an email if that doesn't appear to work. Second-guessing it will probably do more harm than good.

 

[AdamK1025]

Turned it back around and adjusted the contrast while it was on it its working nicely now. such a simple thing that makes such a big difference. Thanks a lot for the help everyone

 

[cerving]

Turned it back around and adjusted the contrast while it was on it its working nicely now. such a simple thing that makes such a big difference. Thanks a lot for the help everyone

Glad it's working, and even gladder that you didn't fry the LCD panel!