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Main => Monitor/Video Forum => Topic started by: epicfatigue on February 24, 2014, 12:00:12 am

Title: MS-2931 Repair (FIXED)
Post by: epicfatigue on February 24, 2014, 12:00:12 am
Hello Everyone,
i have just purchessed a Astroblast City cabinet with a dead 29inch Nanao ms-2931 in it.


I have taken a gamble here but this monitor tube is perfect and the cainet is pretty clean aswell howe ver i am sanding it back and repainting it as i would love to give it to my daughter as a birthday present.

The unit is in transit at the moment so i cant say anything on what its failure looks like just thought i would give a shout out and see what people know of this monitor.

I have started looking around, so far i have the wiring diagram service manual and ever pdf for the IC's thanks to WIKI :)
I do know that it has the gloop of death, which there seems to be conflicting information about, to be honest i dont know what to believe but i will test it for conductivity, seeing that it comes out of a coil i dont see why it would be conductive but who knows what else is mixed in their over time dirt dust coke!

I understand if the flyback is dead then the monitor chasis is kaput, so i figure this would be a really good starting point of testing.
Does anyone have some good documentation of testing flybacks?

I am pretty handy with my electronics and i have all the gear for testing just lack experiance :) but hear to learn and get this out of the way.
I have repaired a few monitors but nothing like this baby.


Just putting the feelers out.

Also anyone know if this requires an isolation transformer? as i need a PSU etc.

Thanks guys

Title: Re: MS-2931 Repair Help
Post by: TOMMYGUN on February 24, 2014, 08:33:05 am
first thing to do is push the wire that go's in the top of the flyback, this can come loose,
Title: Re: MS-2931 Repair Help
Post by: epicfatigue on June 05, 2014, 12:43:29 am
Well with alot of work i have one up and running,
the other one has suffered the same problem but took out the HOT aswell so i am waiting on replacement parts.

Appears the Green is hard on, going to be either the gun in the tube or GReen is being brought on full by something, either way a nice and easy fix.

For all those that were wondering the symptom of this problem was a B+ climbing then a CLICK and shutdown occurs.
Followed by 30 seconds later after being powered off another click.

(https://lh6.googleusercontent.com/-yRE7Y0N9C8w/U4_0c8-KPII/AAAAAAAAVaE/MYf2TDnvEmg/w346-h260/image.jpeg)
Title: Re: MS-2931 Repair (FIXED)
Post by: epicfatigue on June 05, 2014, 07:41:25 pm
So i tested the output transistors on the next board, all appeared perfectly fine,
tested Amp as color comes in fine aswell,

pulled neck off had a look, snaped in half  :angry: at some stage and not repaired correctly, repaired the neck correctly, can never tell it was even broken.

 :cheers:

(https://lh6.googleusercontent.com/-B_38cQ5Y_ps/U5D_aUoVrLI/AAAAAAAAVao/pkRPmLlNjXE/w346-h260/IMG_0183[1].JPG)
Title: Re: MS-2931 Repair (FIXED)
Post by: Slippyblade on June 05, 2014, 07:48:34 pm
Looking good, nice repair!
Title: Re: MS-2931 Repair (FIXED)
Post by: zumbito on August 21, 2018, 01:13:48 pm
Sorry to resurrect this topic but couldn't send a private message to @Epicfatigue and I'm SUPER interested in this, as my blast as just the same issue.

 
Well with alot of work i have one up and running,
the other one has suffered the same problem but took out the HOT aswell so i am waiting on replacement parts.

Appears the Green is hard on, going to be either the gun in the tube or GReen is being brought on full by something, either way a nice and easy fix.

For all those that were wondering the symptom of this problem was a B+ climbing then a CLICK and shutdown occurs.
Followed by 30 seconds later after being powered off another click.

(https://lh6.googleusercontent.com/-yRE7Y0N9C8w/U4_0c8-KPII/AAAAAAAAVaE/MYf2TDnvEmg/w346-h260/image.jpeg)


If you could give me some directions on how to go about this, I would be really thankful.