FIX: Kortek KT-2914DF monitor

[Ken Layton]

Kortek model KT-2914DF (Dyna Flat face) arcade game monitor, 27 inch

Symptom:

Very, very out of focus picture possibly accompanied by a burning smell. Flyback is ok. Notice the dark upper left and upper right corners in the attached picture. The rest of the picture on the monitor is way out of focus. This monitor is installed in a Dance Dance Revolution.

Cause:

The vertical output IC has failed and taken out several other parts with it.

Solution:

Replace these parts:

IC201 Vertical output IC, TDA8172 or NTE 1788

R206 Resistor, 0.47 ohm @ half watt

R207 Resistor, 1.2 ohm @ half watt

R212 Resistor, 22k @ quarter watt

C205 Capacitor, electrolytic, 470 uf @ 16 volts

C204 Capacitor, ceramic disc, .1 uf @ 50 volts

While you have the chassis out, you may as well replace these electrolytic capacitors too since they are likely going bad or are already bad:

C201 Capacitor, 1 uf @ 50 volts

C206 Capacitor, 220 uf @ 50 volts

C209 Capacitor, 4.7 uf @ 50 volts

C708 Capacitor, 1 uf @ 50 volts

C724 Capacitor, 33 uf @ 50 volts

C113 Capacitor, 1000 uf @ 16 volts

C118 Capacitor, 470 uf @ 16 volts

C119 Capacitor, 470 uf @ 16 volts

C801 Capacitor, 100 uf @ 16 volts

Note: the monitor I worked on had a Samsung number A68QCP693X200 picture tube in it.

If you have a model KT-2914F, see this thread at the Vendor Amusements forum to fix it:

http://www.vendoramusements.com/bbs/nph-YaBB.pl?num=1282336686

[qrz]

the TDA8172 was a common failure on several brands of TV ( an RCA favorite )
frequently, the IC will pull additional current prior to it's dying.
the extra current load tended to produce some unusual symptoms.
although, never encountered a screen shot like this one .
and most likely due to the deflection requirements of a "flat" crt...

[harleyrider791]

  What is the insulating material IC 201, TDA 8172 is protected with? No matter how careful I try to be replacing this IC or 2 units, I ruined the insulator. First one could be salvaged, I was more careful or the second one and made more of a mess of it. What could be used in plsce of this material that would do the job?

[Ken Layton]

Mica insulator. If you buy an NTE replacement, it includes a fresh mica insulator in the package.