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bwodie
10th June 2006, 03:23 PM
hey guys
i have a 6 slot cab like the ones at the bottom of here:

http://www.hardmvs.com/xml/pacific/pacCabs.htm

a few weeks ago weird shit started to happen
i would turn it on and i would hear a really loud crackling coming from inside the cabinet.. i didnt know wtf was going on
it sounded like the 6 slot mobo was on fire lol
so i turned it off and ****ed around, turned it back on and it worked.
now this has been happenin every few times i turn it on..
now today it did it pretty bad and now it turns on e.g i get the credit 0's up , i get sound but no picture.
also i got my girlfriend to turn it on, while i watched at the back door to see if i could tell where the crackling was coming from, and it was coming from the little board under the monitor. it crackled like normal for 1 second then i smelt a burning smell and the cracking stopped. im like ****.. i bet the monitor is blown
its a nanao monitor, but it is quite old.. takes a little while to warm up etc
its done pretty bad cracking like this before, and the screen wouldnt come on for a while, and then ive tried it again a day later and its worked, but i dont think ive ever smelt burning before!

i have attached pics of wher the cracking was comin from.

thanks in advance for any help and troubleshooting you can help me with
im a total noob when it comes to monitors etc

http://img301.imageshack.us/my.php?image=hpim09876xw.jpg

http://img106.imageshack.us/my.php?image=hpim09826ak.jpg

4_ur_amusement
10th June 2006, 04:48 PM
on the neckboard there is a little set of posts called a spark arrestor it bleeds voltage if either the earth going to the neckboard is poor or your eht voltage is to high which in turn its fairly likley your plus b voltage is also too high so it sounds like the screen sometimes going off is the chassis xray circuit turning the tube off to prevent damage and the smell and the buzzing is voltage being bleed off

bwodie
10th June 2006, 05:10 PM
ok, thanks allot for the reply.. sounds like maybe im not stuck with a dead screen
the screen never goes off once it has come on, its only when i firstly turn it on do i get trouble.. once its on its happy.
So, i read over your post a few times.
can you explain what you said in laymen's terms.
should i try and figure which wire is the earth wire, and if tis being grounded properly.
if i keep trying to turn the machine on can i **** the screen?
please any help on troubleshooting this further would be greatly appreciated.

4_ur_amusement
10th June 2006, 05:14 PM
firstly dont muck about with it bar a simple look over its best left to the experts from the pics your earth or black wire to the neck board is there and attached if the spark arrestor on the neck board is being fired up ie blue spark and a buzzing noise id say its a eht problem or to much voltage within the chassis either way its beft left to someone who knows what there doing as ehts can carry up to 30000 volts

bwodie
10th June 2006, 05:26 PM
well im in newcastle, i only really know guys at highway entertainment
i guess i will ring them and they might know someone local who can help..
****in hell, really dont want to have to load it into a van

bwodie
10th June 2006, 05:49 PM
hmm well ive had quick chat to an old mate whos an operator
he seems to agree with your gatherer. he got me to take the neck board off to see if there is any visible burning on it, but theres not
he suspects it could also be a dry joint, but i dont know what to look for (tracks etc) hes given me the number of a techy, so hopefully i can get onto him and get some help.

Jomac
13th June 2006, 03:10 AM
Bwodie ,

That monitor isnt a Nanao , it is a standard 15K low resolution kortek monitor with a standard Zenith tube , It will have a green sticker on the tube that clearly says Zenith ,samsung or chungwa .

The part you are seeing the spark come from and getting the burnt smell from is the deflection yoke /coil , it is very common for these the burn out on this model .
It normally starts with a cracking sound which is cause by the bad fitting anode boot on the tube , when it starts to leak it will arc down to the Yoke using all the dust and moisture as the path , the arcing against the coil burns off some of the enamel coating on the wire coils of the yoke causing them to arc together until it burns out .

You will see 2 fuses on your chassis , both small glass 2AG fuses , the one closest to the edge is a 4 amp and the one further in is a 1.25amp , this will be blown !
At times you can be very lucky and thats all that has happened to the chassis , but in some cases it will take out the Horizontal output and ocassionally the power supply section of the chassis .
What ever you do dont put a larger value fuse in where it is blown !

Remove the Yoke coil and look for the visable damage.
You need to mark the coil and convergence rings with a texture so you can put them back exactly where they were .
The tube itself will still be ok , but needs to be cleaned , spray with CRC or WD40 and wipe it clean with a dry rag all over , especially around the Anode cap ( suction cup )

If you send me the chassis and the yoke coil I can test them both and repair or replace whatever necessary .

bwodie
14th June 2006, 03:01 PM
Jomac, thank you for the reply.
I will have to look at the monitor brand more carefully, as I was only going off what my local operator said he replaced the monitor with.

Neither of the fuses blew, and i have taken the neck board off to see if i could see any visible burning on it, but couldn't.
I have been directed to a techy up the coast, who i might get to fix it depending on what Mooncrester thinks, as he has very kindly offered to assist me over the phone. Regardless, it may be better to get some of the parts off to you, so thank you very much for the offer and accurate descriptions. Will get back to the thread and you ASAP :)