Neovo F-419 no power.

[BobMollie]

Re: Neovo F-419 no power.

All components measure ok. However I measure 6.61 volts across C809 with power to the board and the logic board not connected.

[selldoor]

Re: Neovo F-419 no power.

can you do the tests mentioned in this post
https://www.badcaps.net/forum/showpo...2&postcount=21

[selldoor]

Re: Neovo F-419 no power.

I have been checking for fuses but cant see any small ones on the back of the board.
If budm does not come back on I will have a look back at the whole thread tomorrow.

Not sure what you mean about the board layout being different - perhaps small differences? the board number and revision are the same as the OP?
he has posted a schematic in post 1? is it not relevant?



LATER - I see now you mean a different Main board

[newtothis]

Re: Neovo F-419 no power.

Oops missed a page of the thread

*** EDITED ***

[BobMollie]

Re: Neovo F-419 no power.

Is their any one that can help me trouble shoot my Neovo F419 monitor?

[BobMollie]

Re: Neovo F-419 no power.

Budm are you their.

[BobMollie]

Re: Neovo F-419 no power.



Budm, Diodes D841 and D842 test ok. See the foil side of the two circuit boards.

[budm]

Re: Neovo F-419 no power.

So it is dead without the logic/main board connected.
You will need to check the rectifier diode D841 mounted on the heatsink and D842 to ake sure they are not shorted. If they are OK, then we need to find out if there are shorted circuit in the inverter section.
I will need good clear pictures of the bottom side of the board.

[BobMollie]

Re: Neovo F-419 no power.

budm are u their?

[BobMollie]

Re: Neovo F-419 no power.

I have 0 volts on everything except the Green had 0.017 vdc and the Blu had 0,05 vdc.

[budm]

Re: Neovo F-419 no power.

What DCV do you have at the white connector that has the cable going to the Logic board (disconnect the cable to the logic board first)?

[BobMollie]

Re: Neovo F-419 no power.

I have read the articles. Does anyone have a schematic of this board, or any info on the board?

[BobMollie]

Re: Neovo F-419 no power.

Here are some pictures of the power supply board and the logic board. The unit does not turn on nor does the LED power light. I do have 167 volts across C805.

[budm]

Re: Neovo F-419 no power.

Is this thread still going. I have a power issue with a Neovo F419 also. The only problem is that my board layout is different the what is being shown here.

So show us good clear and focused pictures of your boards to start with.

[BobMollie]

Re: Neovo F-419 no power.

Is this thread still going. I have a power issue with a Neovo F419 also. The only problem is that my board layout is different the what is being shown here.

[retiredcaps]

Re: Neovo F-419 no power.

BTW do you know of some good newbie soldering 101 site, i've found some but none that were good enough.

CuriousInventor has excellent videos

http://www.youtube.com/watch?v=3NN7UGWYmBY

[alexanna]

Re: Neovo F-419 no power.

Buy some Chip Quik for Digi-Key it makes removing the small IC a snap.
When you solder the new part in coat the pads and pins with flux, Then with a fine tip soldering iron melt some solder on the tip, and like you are drawing a line with a pencil start at the solder pad and drag the solder to and on the pins of the IC.

[playman]

Re: Neovo F-419 no power.

Still, this looks very much like U801 has failed. I'd say it's time to replace it

That's a shame, it will be interesting how it will go when I try to solder the new one in, there are so small solderings on it lol.

It might take some time to get the part.
what should I do after I have replaced it? just put it to gather and test the screen?

BTW do you know of some good newbie soldering 101 site, i've found some but none that were good enough.

[PlainBill]

Re: Neovo F-419 no power.

V- to U801 pin1 = 0v
V- to U801 pin3 = 3.32v on 20VDC
V- to U801 pin6 = 0v
I started @ 600VDC and went down to 20VDC
Used the black probe on V- and Red on U801


And I laughed

I'm having a problem getting my head around the readings you have gotten at various times on the V+ to U801 pin 1 path. Still, this looks very much like U801 has failed. I'd say it's time to replace it.

PlainBill

[playman]

Re: Neovo F-419 no power.

V- to U801 pin1 = 0v
V- to U801 pin3 = 3.32v on 20VDC
V- to U801 pin6 = 0v
I started @ 600VDC and went down to 20VDC
Used the black probe on V- and Red on U801

The best way to make a crappy DMM better is to sell it and buy a new one. Recently we have had a few cases where the problem was the 'organism' holding the probes.

And I laughed