XM-2001N - Replaced flyback. Loud hum. No picture.

AlienInferno

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All right. So I have a Atari Blasteroids with a Sharp XM-2001N monitor. The colors where so dim you couldn't see the picture unless the room was completely dark. Figured I would do a cap kit on it to see if it brightened it up any and noticed the flyback had a crack in it. The piece that holds the two turn knobs was about to fall off.

I bought a flyback from here: http://www.ebay.com/itm/Sharp-XM180...=item3d04598dd0:g:nGkAAOSwQTVWBeTv&rmvSB=true

I installed it today as well as fixed a few solder joints/lifted traces and replacing the resistors at R605 and R607. I still have yet to do the cap kit.

I reinstalled everything to test and when I power up I don't get a picture and I get a loud humming noise from the monitor. Also I noticed that with the power on I don't get anything on the screen, but once I switch the machine off I have a blue colored dot in the middle of the screen. I do have neck glow for a short time and then it just disappeared along with the hum until I turn it off and back on again.

Any help would be appreciated as I have zero idea what I'm really doing. First time working on a monitor.
 
You didn't install the wires backwards did you? The thick wire solders to the focus post on the socket connection. The thin wire solders to the neckboard. This has been known to happen.
 
Yeah I'm pretty sure I put them the right way. I checked and rechecked before I soldered them on. Especially since all the wiring on the new flyback was red. I'll check again in the morning just in case though.
 
did you turn the screen control pot up on the flyback?? they are usually off when they come new which will act like dead/nothing on the screen, etc.
 
OK. So I did wire the flyback correctly to the neckboard and focus post. After reading security0001's post I turned the screen control pot up and got what is shown in the video. Still have the loud humming noise. (way louder then your typical crt hum. Not sure if it comes across in the video though) Still have the white/blue dot but with the screen control pot adjusted anywhere but off I get the color "field" as seen in the video when power is cut to the machine. Also right after I cut the power there was a loud pop or crack. (heard right at the end of the video). Really hope the monitor still works after that.

https://www.youtube.com/watch?v=FI9zdWG0YCE
 
Do any of ya'll believe that this flyback could be bad? It's really the only thing I've changed other then resoldering a couple resistors. I do have a second one to try or I could put the old one back on to see if I get anything different. The only downside is that the knobs for screen and focus are no longer attached to the original flyback.

Still haven't figured out what the loud pop was either at the end of the video. Couldn't physically see anything wrong. Nothing was cracked, no smoke, all fuses are still good.
 
Flyback

When you replaced the flyback was it hard to install? Meaning, did you have to use any force to install it? I've had chassis and flybacks that were really damn tight and using any force can flex the chassis PCB and cause issues. I did this on a G07 once.
 
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