Uniden Bearcat 980 set up

[brandon7861]

I have a 980 that has spent its life indoors in Minnesota and the display is starting to fade on it, so I don't think it is a temperature issue. The segments on the right go first, fading out slowly. The odd part is that leaving it alone for a while will bring the display back up, but only to fade out again. It would seem the failure is internal to the screen itself, as others have replaced it with success (only to have the problem come back in about the same amount of time).

My guess is that there is a DC component (perhaps only mV) to the segments that slowly destroys the LCD due to ion migration and space charge effects. That would explain the slow fade out over months to years and probably the temporary contrast return as well. I suspect that proper DC blocking might save screens that haven't failed yet, but I have not investigated it yet and all this is speculation. Some day.

 

[Shadetree Mechanic]

I got a 980 one time when they were on sale at Amazon for $99. Great radio, clear audio (although a bit narrow) and stays on frequency. The wireless microphone made for it works really well and has excellent range. The display was an attempt to modernize and they did a good job making it look like a stereo cd player. So it might look good in a double din slot with a CD player below it. It is not a deep radio so fits perfectly in dash.

I used mine as a base on the back workbench with a KL203 and worked lots of DX while using a D104m6b. Then I used it as a station monitor for a while, and now it sits in the box on the shelf. I never experienced the display issues, but maybe I didn't use it long enough.

I almost used it in one of my ammo can portable setups. But then I discovered that the McKinley is a short radio too, so that's what I used because the McKinley looks the part.

 

[nomadradio]

proper DC blocking might save screens that haven't failed yet,

I remember reading about LCD driver chips long ago. They stressed that the drive waveforms had to have a perfect 50 percent duty cycle, to prevent any DC offset. They said display life would be shortened if that spec was not perfect. Even a tiny net DC component would degrade the display. Whatever LSI that radio uses to drive the display should have this requirement built into it. The LCD drive does have to be DC coupled, pretty sure. Don't think the capacitor idea would help.

73