50% Loading Display DM8000HD

Hello friends,

This is the first time a problem occurs on my dm8000 clone. It simply does not load until the end after end and does not enter image. I was using "openpli-7.0-release-dm8000-20190304_Japhar" which by the way was the best japhar image I used. However, the symptom began with the total stop of the signals in the tuners. The procedure I did was restart the dm8000. But it only carries half for loading in display.
I've already done it and it did not work:
* Installed image 87F;
* I installed japhar 87 and 84 image via serial cable;
* Reinstalled 87F with cable via serial and recovery bad option activated;
* Returned to simcard ferrari and installed via serial mode.

Even so, all the options have had no effect and the box continues to load halfway without displaying an image in the video output.

ps. I have no problem transferring images to files with .nfi extension through network cable or serial mode.

Can it be a power source?

Thank you!

Ultra_signal

Best tip :

- Stay with Japhar Sim, as it does FERRARI + JAPHAR images. If possible upgrade it to v6 OS (as explained, with GCR2 or Frontpanel via JAM plugin or internally with JAM plugin).

This done, then most probably you will still have the same issue, as I would bet it's a Capacitor problem due to the PSU. If image boots (any of them, Ferrari AND Japhar) then it was only a corrupted image/flash.

Read the PSU tip, and replace the small capacitor first (22uF/50V (C109) Model V1 or 47uF/50V Model V2 better is Rubycon always). Some members instead of 50V models took the 63V one that seems even better. Then try to see if this fix the problem. Check the 4 capacitors if these have "hills", or these seems to be bad, replace them by Rubycon same 1000uF/35V (or higher V).

See : http://www.ourdreambox.com/ubbthreads.php?ubb=showflat&Number=1592#Post1592

Admin

resolved friend. It was the capacitors. My network here is 220V and has a lot of oscillation. I reconnected to the UPS at 127V.

Tks!!!

Great news, and remember that capacitors also have some limit in time, so every few years this could be necessary to repair/replace again.

Admin

Hello Friend,

Again, there was a problem with the PSU. The dm8000 loads up to 50% and no picture appears. I made the measurements at the source output and found zero volts at pin 3 (7V). Can you help me solve this problem? What do I need to replace? Replaces all 4 capacitors of 1000uF and 2 capacitors of 47uF by Rubycon of 130 C. It also replaces the two large 82uF.

Could you tell which IC responsible for sending the 7volts. I know this pin changes tension.

Thank you!

You have Model 2 of the PSU,

It seems you changed the C109, that is 47uF / 50V ? You can use 63 Volts one, should even be better. If possible by a Rubycon at 105° or 130° if available/findable.

There is also the C404, 2200uF 10V, that could give problems sometimes.

But Johnny is the best on this, so let's see what he tells.

Admin

Issue, pin 3 with a 5L0565 PSU may be caused due a issue with the Pcu, but may also be caused due the motherboard, the extra tuners, or the U1401/U1404 5v regulators.
More about this tuners measurements, see here,
https://jb8a8f8.com/support/index.php?threads/8000hd-tuner-related-measurements.94/

In any case, it's better to measure from the Psu, the Ohm value from this pin, see this picture for more about it.
https://jb8a8f8.com/support/index.php?attachments/dm8000hd-psu-vdc-ohm-measurements-jpg.167/

This pin makes contact or passes several parts as the,
C602
C603
R8
L608
D12

And will eventually end up to the U2
More measurements about this and more, see here,
https://jb8a8f8.com/support/index.php?threads/dm8000hd-5l0565-psu-voltages-measurements.121/
Check in any case the D12 diode if it's caused due the psu side.

There is also a way to activate the psu, without connected to the motherboard by feeding a 3.3v,
More about it, see here,
https://jb8a8f8.com/support/index.php?threads/testing-the-dm8000hd-psu-without-the-motherboard.84/

However be careful with the hot zone side when it's active.

THANK YOU MASTER. Sorted out. No complicated maintenance. I have found poorly or sold soldered in the power terminals of the HD and DVD.

THANK YOU MASTER!

Now he was confused. I hooked an additional external tuner dvb-c and returned to give the problem. Is it my U2 voltage regulator (MP1484) that is not supplying minimal electrical current?

I performed measurements of U2 and D12. Please confirm that I need to replace U2 (MP1484).
thank you very much!

Only when this happens when the power supply failed when it's tested without the motherboard.
You could do this test also by disable the pin 3 wire between the psu and the motherboard.
When it's still failed as you have measured, then I would replace the ic, but check at least the diode if it's leaking before you do the other things.
Useless to say that you need to remove the diode, or at least one side from the pcb to test it with a multimeter on diode settings.
Or else, just replace the diode to see if it solves the issue.

I removed the external DVB-C tuner and the box came back on. I have redone the measurements, and they are the same (all measurements were taken with the motherboard connected to the power supply). How do I check the D12? The direct and reverse voltage on D12 is the same as on pin 3 on U2.

See youtube, diode measurement multimeter
In any case, you must at least disconnect one side of the diode from the pcb to measure it correctly.