Re: QCX: top row blocks on display, but CPU responds to ISP #avr #display #troubleshooting


 

Did you try swapping out the IC2 for one where the display is good? I did that and the display worked again as it also got the row of blocks on the top, but, the RX has also gone. Both RX and display were fine, this is a neewly constructed QCX-2017-v-2, all was good except TX which blew earlier. In its Baumatech case, running for weeks on RX with no issues (and not TX), from one day to the next on power up there was the blocks along the top. Normally this one required starting twice to get it to power up (old bug, which hasn't been fixed on this model), but this time no, just blocks on the display. Swapping out IC2 from another QCX brought the display to life, but no RX!

I'll try to trouble shoot it at some point with help from this list but for now just wondering if your problem might be similar. Presumably you can't hear the RX withouut being able to start it up with the display? And presumably you have tried putting in a different working IC2?

77 de Lou

On 23 Jun 2021, at 19:58, Andrea Massucco IZ1IVA <ml@...> wrote:

Thank you gentlemen, unfortunately resoldering hasn't solved the issue. Since che CPU is working (as it's accessible via ISP), I'm tempted to blame the display assembly, perhaps the rubber contacts between the display and the PCB... if that's the case I fear I'd need a new display board.
--
73 de Andrea IZ1IVA - cq at iz1iva . net - http://iz1iva.net




--
Love 30m and CW?
http://www.30cw.net

Join QRPLabs@groups.io to automatically receive all group messages.