PreenFM3 screen missing text, turning all white regularly

[jdlesemajeste]

Hello, I recently bought a used PreenFM3, I do not know who assembled it or anything like that, but all the audio elements are working but the screen regularly turns all white, I don't notice a pattern, it seems to be random. In addition to this, when I select a new preset or change screens, the screen won't be fully updated, so that it will list only the first three items.

I opened it up and took the attached pictures of the screen jumper solder points, I reflowed and added a little solder to a few that looked a little lacking but otherwise I can't see anything too wrong. As far as power supplies go, I have experienced this using a CIOKS DC5 and also the "JFEC" adapter that came along with it. Sorry about the pictures, my original pictures were too large and so I resized them but it is still rather large for the forum. Let me know if you see specific pictures of any section.

Sometimes it will happen frequently, sometimes it not happen for a while but it does occur at least once per "session".

The screen is always able to be reset using MENU + '-' however this doesn't work in the MIDI controller mode, which I would suggest implementing because I get white screens when using the MIDI control mode and can't MENU- out of it.

Thank you for any suggestions.

[jdlesemajeste]

FYI I've ordered some new screens to test out. I wonder if this problem is caused by a certain batch of screens that don't act right. Even with the TFT set to auto-reset, sometimes it stays white, sometimes it successfully autoresets. I'm going to try the new screens and see if they fix things.

[jdlesemajeste]

I have now also discovered that my unit is not passing MIDI out of the MIDI port. I will open it up again this weekend and check out the solders around the MIDI port. It is possible that I bought a poorly-assembled DIY unit.

[jdlesemajeste]

Sorry I have not given you a chance to reply Xavier, I have put a new screen in my new unit and it seems to have fixed the problem. This is the screen that I used: https://www.amazon.com/dp/B073R7BH1B?psc=1&ref=ppx_yo2ov_dt_b_product_details If anyone experiences this problem I would first replace the screen

Note it is a touch screen, perhaps this makes a difference. It is a little expensive but it looks much better and also doesn't white-screen (or hasn't yet in the time period I would expect it to) I am sure this is a DIY unit, there's a few other aspects of the construction I'm not happy with but I can fix back at the shop. I would expect that the screen the builder used was not a high-quality screen and so it wasn't reliable.

Now the only issue is the lack of MIDI out, there's a lot of debris on the board and the solder points around the jack look like something I would do.

[jdlesemajeste]

Well, I took it all apart, reflowed the solder points connecting MIDI out and retouched a bunch of stuff and cleaned and cleaned and cleaned and initial testing shows that MIDI through is working perfectly well, so I assume MIDI out is working correctly too, although I have not completely verified this with the MIDI controller mode. It will be very nice if that happens to work.

Mark this one as 'solved.'

[Xavier]

Sorry for not replying.
And thanks you very much for the update and
The 2 last weeks were really busy.

I'm really glad you found solution for your 2 problems 

Yes those displays are very sensitive to any electronical noise, and some models just lost the connection with the preenfm3.
That's very usefull for me to know you fixed the problem by swaping the screen.

[jdlesemajeste]

No worries, I assumed you were busy. The replacement screens I bought were a little pricey and also the touchscreen version. I also ordered some very cheap screens that are not touchscreen, I think there was either a bad batch or some screen are more prone to whitescreening. I'm curious myself, I'll let you know.

[cokosha]

Hello Xavier
Hello Jdlesemajeste

I noticed that displays from the same batch may or may not show this problem.