Kortek KT-2182 chassis - not turning on (worked fine a few days ago)

[Midcoastsurf]

001 is probably the closest my DMM will read to 0.4

[bumblebb360]

Hello it to have a KT-2182 chassis for a PGA Tour Cab. I have an issue with the monitor coming on for about 3 minutes then the image compresses vertically. I pulled to board out and looked for anything obvious. Stupidly I did not take any pictures before pulling it out. Does it matter which way the power cable plugs back into the board ?  I plugged everything back in to see if I got lucky but same thing and smelt burning. I pulled the power quickly. I have pulled the board again and resoldered the pins on the vertical IC chip. can someone help make sure I have the power plug in correctly and what you may think the issue is?

[grantspain]

Hello it to have a KT-2182 chassis for a PGA Tour Cab. I have an issue with the monitor coming on for about 3 minutes then the image compresses vertically. I pulled to board out and looked for anything obvious. Stupidly I did not take any pictures before pulling it out. Does it matter which way the power cable plugs back into the board ?  I plugged everything back in to see if I got lucky but same thing and smelt burning. I pulled the power quickly. I have pulled the board again and resoldered the pins on the vertical IC chip. can someone help make sure I have the power plug in correctly and what you may think the issue is?

seen that on kt2914f chassis and you need to change some caps and resistors around the v def ic,good to change the v def ic also

[bumblebb360]

Thanks. Do you have any idea on the power connection? It is not keyed like most cables.

[bumblebb360]

I got the monitor working! I re-soldered the vertical IC chip and now it works. The corners are discolored and its dark. Brightness is at 100%. Its hard to see the fairways. Is there brightness controls on the board?

[grantspain]

I got the monitor working! I re-soldered the vertical IC chip and now it works. The corners are discolored and its dark. Brightness is at 100%. Its hard to see the fairways. Is there brightness controls on the board?

not worked on that chassis but the kt2914f has a factory setting you can access and gives loads of options
to access hold "up" to on position and then power on monitor

i have had to do this loads of times to these chassis to get extra contrast/colours and brightness

[Midcoastsurf]

Hmm....I pulled the HOT and measured the voltage at D120.  The voltage was about 5 volts...then a few seconds later, I re-measured it and all big Diodes in that area were down to 0.  I put a new HOT in while I had the board pulled just for good measure.  Where should I look now?  The board is definitely getting power and both fuse clips measure around 120v.

Thanks

[Midcoastsurf]

What would someone charge to take a look at/fix this board?  I don't know what else to do with it.

Thanks

[lilshawn]

sounds like you are getting a few good switches out of the FET that is charging up the caps but then it breaks down so they bleed off...that's what you are measuring.

I would take a stab at it, but i have nothing tube wise comparable to it to test with...and it would cost many times over what a new monitor would cost to ship the works to me.

[Midcoastsurf]

lilshawn,

Is there a reason the MOSFET would stop switching, or is the MOSFET itself possibly bad?  I still need to test L108 for voltage, unless it doesn't really matter right now since none of the large diodes in the power supply section are getting power.

When testing the chassis, does it need to be hooked up completely and the anode attached to the tube or can I power up the chassis outside of the game?  I have always re-hooked everything back up before powering up the chassis.  Thinking back to when I pulled the board to check the HOT, I did forget to attach the anode cup to the tube when I hooked everything back up and it sparked against the metal frame that the chassis mounts to    After this incident, no more power at the big diodes...
 

[lilshawn]

it sparked against the metal frame that the chassis mounts to

your HOT might be toasted now. remove the HOT completely and retest for voltages on the secondary side.

the power supply has 2 sides...a primary side and a secondary side. the 2 sides are separated by the yellow transformer. the primary side has the main AC, the big huge capacitor, the MOSFET switcher and some other supporting components.

the secondary side has all the choke coils, capacitors, diodes and goes on to feed various voltages to the rest of the system.

[Midcoastsurf]

The spark happened before replacing the HOT.  I was replacing the insulating material behind the old HOT.

Maybe we need a Skype support hotline. Members can join in and learn/ give advice.

[Midcoastsurf]

Any thoughts on what components should be checked next...or which line on the schematic I should be following?  Do I just trace backwards from the large power diodes? (D120).

Thanks

[Midcoastsurf]

I finished replaced a few caps near the bridge diode and one near R118.  I also replaced the large filter cap as it looked questionable and I was only getting 87vDC to the bridge diode.  The monitor is back up and working.  I will keep it on for the rest of the day to test it out.

Thanks

[lilshawn]

sorry, i meant to post a reply awhile back and I thought about what and then forgot, or thought I did, an forgot or...something...i think.

Didn't mean to leave you hangin' Glad it's working again though.