New Life Games LLC

Monitor Repair Log and Database. **Arcade and Gaming** => LCD and CRT Monitor Repair Tech Support => Topic started by: firebird71 on December 06, 2015, 04:52:07 PM

Title: Kortek Blacking Out
Post by: firebird71 on December 06, 2015, 04:52:07 PM
I have a Kortek 1703 monitor that blacks out after about 20 min. When the monitor blacks out, it kills the cap# c121, and c408, it also takes out the H.O.T. Another thing that may be important is that the heat sink for the H.O.T. is very hot when it blacks out. If I replace the caps, it will come back on but will only last for about 20 min. Any help would be appreciated.
Title: Re: Kortek Blacking Out
Post by: cowboygames on December 06, 2015, 05:31:36 PM
What voltage reading are you getting on the collector leg of the HOT when it's running? Should be 130v. I would suspect a faulty voltage regulator transistor or leaky diode first
Title: Re: Kortek Blacking Out
Post by: firebird71 on December 07, 2015, 04:15:26 PM
Okay I put the negative lead of the multimeter on the base, and the positive lead of the meter to the collector but I am not getting any readings. I have the meter set to 200vdc, but am getting nothing. I am new to this and hope I connected it right. I did unplug the monitor before it failed so it should fire back up for another test.
Title: Re: Kortek Blacking Out
Post by: cowboygames on December 07, 2015, 04:44:27 PM
Just go centrr leg to ground. With the unit running, should be around 130v
Title: Re: Kortek Blacking Out
Post by: firebird71 on December 08, 2015, 10:39:55 AM
OK, now I am confused, I connected to center leg and grounded to the chassis, I still get no reading, but the monitor is running. I have checked for both AC and DC voltages, but nothing.
Title: Re: Kortek Blacking Out
Post by: cowboygames on December 08, 2015, 02:39:59 PM
Me too, there has to be voltage there to get horizontal drive
Title: Re: Kortek Blacking Out
Post by: JustTech on May 07, 2016, 09:41:22 AM
Your power supply is running off with voltage if you check your voltage on C121 you will find it high should be around 65 volts according to the schematic try to see if replacing c107 and c108 in primary circuit will bring your voltage back down.


JustTech
SimplePortal 2.3.5 © 2008-2012, SimplePortal