Kortek Monitors Tips,Tricks and Cap Kits

[Ohmerone]

Poor to no width.

Replace T303 Part# Sct-82D
Replace L304 Part# 7R5
Hot Upgrade From C5584 to FJL6820 The Horizontal Output Transistor
Also used in the KT-3414df and KT-2938F or BF and Kt-2914F

Low Brightness,turn up master brightness on fly and still very dark
replace C118 470 16v Low filament voltage, voltage
comes from Power supply, not fly!
I have found a few bad caps over repairing a few chassis
I have a list of caps that measure bad everytime.
Will post soon.

Power supply T101 also loose's connections
scratch back pcb from transformer pins and resolder
pins and trace for good connection both sides of transformer.

Resolder the caps at C728,C727,C709,C705,C702
solder in good before its to late or it burns a hole
in the chassis,once they get a poor connection
it just gets worse.


KT-2914f

Cap List;
TB Test Bad.

C804 10/ 160V
C801 100/16V
C810 220/16V
C823 220/16V
C834 3.3/50V

C801B 1/50BP
C801G 1/50BP
C801R 1/50BP
All tested bad comparing to new Bipolar Caps.

C118 470/16V
C138 220/16V
C112 1000/16V
C113 1000/16V
C101 47/160V
C119 470/16V
C123 33/50V
C125 1/50V
C304 470/16V
C135 470/16V
C130 47/350V
C126 100/100V
C201 1/50V
C206 220/50V
C209 4.7/50V
C205 470/16V
C203 470/16V
C724 33/50V
C730 220/16v
C608 1/50v
C614 220/16v
C607 47/16v
C617 33/50v
C620 3.3/50v BP
C602 100/100v
C508 47/16v

 

[KenLayton]

What model is this for?

 

[Ohmerone]

What model is this for?

Hey Ken,

This is for the KT-3414df and KT-2938F or BF and Kt-2914F
All three have the transformers.
Used in different games,like Fast & Furious 29",Dance dance 34 inch
Etc. I'm getting the Cap List per model, the most common bad caps
Not all caps need to be changed at once.I will list a symptom with a defective part
per model,as i get time.

 

[Ohmerone]

Parts NLA

Schematics for Crt base Models

PDF and Mircosoft Word

and Excel spreadsheets

Should be all their models.

Most if not All Parts discontinued.

Casinotech.. Not repairing most if not all Models.

Or call..

http://www.casinotech.com/kortek/tech_docs/il/crt_tech_docs_il.html

Some Tips at website with models.

http://www.casinotech.com/

 

[Ohmerone]

Chassis Tips

Vertical collapse. Kt2914-Kt-3214 Horizontal line
Need to replace Ic201 Nte Ok, or open Trace or R206.R207 Open
also a 10k ohm maybe R211 may test good but look bad.

Can use a thermal insulator TP0010
instead of the the old damaged one that was there.
Heatsink is not ground..
Part of the symptom is a dark picture with a horizontal line
at top of image and bottom of image looks like no video and out of focus.

To disable shutdown remove Q103
it keeps the 12v's to Ic301 hi to measure the Horizontal Drive
to check the Ic is good and at the correct frequency's
and for your C/S table on schematic for scan mosfet switching is correct
and check mosfets for each scan Q703,06,08 and their switch drive trans
Q704,07,09 often when the mosfets are damaged you could also
have a switch drive transistor bad.
During troubleshooting you can disable the fly by removing lifting
one end of L601 as well, depending where your in the TS procedure.

Wrong primary color's from neck board caps on Neck board including C801 RGB.


More Tips's KT-3414

Alot of the chassis could have the same circuit parts failing and need to check

these parts in all chassis..

Dead Ticking, Shorted Q710 a N channel Mosfet and Open R732 off the 250v Line..


Vertical line up and down the screen first check C130 could have a bad solder connection

to a cap leg or open trace around it..Its supplys the 250vs to Mosfet Q710.

 

[cadillacman]

finally some kortek info!!!

Im getting ready to dig into one that had vertical collapse and no no pic supposedly. Its cold because its been in my van, im resisting the temptation to test it tonight.

THANK YOU for posting man.

 

[cadillacman]

Ok... Mine is the 2914f as well! So im not alone lol.

Im told it was in deflection failure and then quit completely.

I found the red wire at the yoke connector backed halfway out causing poor connection and it partially melted the yoke connector.

I temporarily slid it back into place but still nothing..

Can i get to the on screen menu without a video signal present or do these need a video signal to stay on?

My led is on at the remote board so i know i have some sort of power. When turned on i hear the power relay click in... a few secs later it clicks back out. I do not see neck glow.




Much to my dismay i see "sam young" caps on this chassis. Ugh. FML.

EDIT i messed with the yoke wire more and got it to fit tight temoorarily. I gently wiggled the large transformer and then the heatsink mounted ic directly behind it. Now the power keeps cycling still see nothing on screen but i keep hearing a cap hissing somewhere when the chassis is trying to power up.. THe heatsink mounted ic has to be in the right spot for this to happen. I guess its time to pull the chassis, check over for bad solder there and shotgun in a few caps, and pray.. Being these are cheapass sam young caps hopefully the bad cap(s) will be obioulsy blown. Wish me luck.


If i need a new vert ic, does this look like a suitable enough replacement?
http://www.ebay.com/itm/TDA8172-NEW...760?pt=LH_DefaultDomain_0&hash=item2a28247aa0

 

[Ohmerone]

Yes

Ok... Mine is the 2914f as well! So im not alone lol.

Im told it was in deflection failure and then quit completely.

I found the red wire at the yoke connector backed halfway out causing poor connection and it partially melted the yoke connector.

I temporarily slid it back into place but still nothing..

Can i get to the on screen menu without a video signal present or do these need a video signal to stay on?

My led is on at the remote board so i know i have some sort of power. When turned on i hear the power relay click in... a few secs later it clicks back out. I do not see neck glow.




Much to my dismay i see "sam young" caps on this chassis. Ugh. FML.

EDIT i messed with the yoke wire more and got it to fit tight temoorarily. I gently wiggled the large transformer and then the heatsink mounted ic directly behind it. Now the power keeps cycling still see nothing on screen but i keep hearing a cap hissing somewhere when the chassis is trying to power up.. THe heatsink mounted ic has to be in the right spot for this to happen. I guess its time to pull the chassis, check over for bad solder there and shotgun in a few caps, and pray.. Being these are cheapass sam young caps hopefully the bad cap(s) will be obioulsy blown. Wish me luck.


If i need a new vert ic, does this look like a suitable enough replacement?
http://www.ebay.com/itm/TDA8172-NEW...760?pt=LH_DefaultDomain_0&hash=item2a28247aa0

Replace the parts first..

Get the last 3 Ics they are used in other chassis.

I would choose those over Nte anyday.

Remove the chassis clear the bench off you need to replace the

Ic and clean your male pins for the yoke and clean the yoke connector good.

Next measure the resistor and remove the ic201 then replace it.

confirm the resistor's are spot on and have not open or increased in resistance.

replace the caps in the vertical circuit or a cap kit, do this now.

Use my experience and your labor replace all resistors with the correct wattage

and tolerance or you could have vertical linearity issues...

The Vertical chip is killing the smps

and the click noise is the degausser closing and releasing.

its common to pulse once via the micro at plugin.

the tri res use a relay for the temporary degauss at plugin or power up.

you have a shutdown scenario and no need to look for OSD

or waste time trouble shooting..get your parts and replace them.

then test again..don't open any trace's,Good Luck!

 

[cadillacman]

alright... ordered the vertical ic (tda 8172... i did get 2 just in case) and working on finding the caps im gonna need now.


Looks like r207 is smoked, the trace still connects but its hanging loose from the board so im going to have to so a little trace work there. Looks like some bad solder joints on some diodes near there as well.

Does that vert ic go and takes out r207 with it? Its wide open no continuity. Should be 1.0 ohm (1.2 watt) according to the manual. Is that correct?

I have a ton of super nice .67 ohm high watt flameproof resistors..... is there any way i can use one of those or does this need to be dead nuts 1.0 ohm?

And lucky me, this was made in 09 and already repaired once in 2010.. some trace work done under the yoke connector pins(imagine that lol)

 

[Ohmerone]

Yes Both resistor are very important for the balance of the supply

voltages,to the Ic or wouldn't have mention it. the third resistor

did you notice it? its like a .8 watt resistor very small..

It gets over heat and may increase in resistance.


When i service these chassis thats the first place i check

for any damage, sometimes the set is shuting down other times

the chassis has vertical collapse.



The Ic draws the current in a case where it draws to much the

supply resistors get over heated...and open up.

The size of the resistors could apply to where they sit on the chassis

and thier tolerance and wattage.

Tip you can stand the resistor inside the heatsink up like a bobby pen shape

but you want the body side only near the heatsink..so the legs don't touch

the heatsink even if it isn't grounded.. this also will help to keep any stress of the pcb trace.

I too have pulled out a series of resistors and notice that my linerity

wasn't right..and had to order the correct part..and wasn't happy.

You should relate to what i say not leave it out,,like your not saying anything

about R206, you need to replying to the parts i talk about..

if you checked r206 you need to reply

to me r206 and the .8th watt resistor checked correctly or what you found..

One of my first thoughts was when i used the wrong resistance was is my Ic bad?

So I grabbed another one only to see the same results..

R207 is a 1.2 ohm @.5 watt
R206 is a .47 ohm @.5 watt
I didnt make good notes on the third resistor
next time i can check this location

Anytime you deal with very low ohms you need to zero your meter and know what

any internal resistance your meter has because it will be added to your total amount.

just a tip.. mainly for measuring very low resistance.

 

[cadillacman]

Yeah sorry about that man i had time last night to pull the chawsis and gave it a quick lookover My meter rears kinds goofy so i am adding .3 on everything because it says .3 with the meter leads touching.

R207(in circuit): 1.8k and climbing(so its open lol)

R206 (in circuit): 1.1 ohm

r211 10k ohms dead on

r212 4.45k

R618(in ckt) Dead on 8 ohms, looks bad may be ok will research that.

also bad solder: r114, d703,r207,d704,q701,t303, etc

FWIW: Hot does not(or did not) check shorted.


Reflowed all questionable spots, replaced r207. Now power keeps cycling (led on remote board blinks, can hear hv kick up and then off repeatedly

Guess im stuck until my new vertical ic and capkit shows up.. and i have to hunt down some .47 ohm resistors somewhere... Im hoping the ic is now pulling the power down and causing shitdown, now thats its actualy connected again via the new resistor.

WOuld it be o.k. to up the wattage on r206 and r207 to say some 2 watt resistors? Im thinking from a longevity standpoint it may be a good idea but im no expert on these chassis whatsoever.

 

[GuidoTorpedo]

Subscribing. Just got in 3 PGA cabs with kortek vga's in them. One works fine. One has "the aquarium effect" on certain screens/color hues, looks like caps needed. One is dead, but was not dead when bought. Screen was folded over badly, looking like caps, but now dead.

Mike

 

[ekeeb]

I have 3 with issues,cant wait to get into these.

 

[cbuschief]

if you don't do a complete cap kit, you need to check/ replace caps in the power supply area as well. They supply the plus and minus 12 volts to the verticle section.There are 1000ufd caps (two of them) and I think the other is a 47 or 470ufd right behind the transformer that should be replaced. Best advice is to change them so you don't get it put back together only to find you are missing some of your picture at the top of the screen.

 

[cadillacman]

yeah u got a capkit coming from bob roberts and i think i will just bite the bullet and change them all while i have the chassis out.

 

[cadillacman]

The slow trickle of parts are finally arriving. I got a full capkit from bob roberts, .47 ohm resistors(ebay), new vert ics(ebay), and my other 1.2 ohm resistors(ebay) showed up but i ordered wrong, they are 1.2k!! Whoops.

So i put in another order, i found some nice little 5 watt ceramic ones that should live much longer and take the heat. The .47 ohms are like a standard resistor but also higher wattage 2 or 3 watts iirc.

I will cherry pick the closest resistors and install once they arrive. I plan on getting to this stuff this weekend if my other resistors show up that is.

Thankfully so far most of these parts are only a few bucks and i should have leftovers for next time.

 

[Ohmerone]

The slow trickle of parts are finally arriving. I got a full capkit from bob roberts, .47 ohm resistors(ebay), new vert ics(ebay), and my other 1.2 ohm resistors(ebay) showed up but i ordered wrong, they are 1.2k!! Whoops.

So i put in another order, i found some nice little 5 watt ceramic ones that should live much longer and take the heat. The .47 ohms are like a standard resistor but also higher wattage 2 or 3 watts iirc.

I will cherry pick the closest resistors and install once they arrive. I plan on getting to this stuff this weekend if my other resistors show up that is.

Thankfully so far most of these parts are only a few bucks and i should have leftovers for next time.

CM, No I don't see any reason to change the wattage on the resistor's

or I would have said change the wattage on the resistor in my tips..

The Vertical Ic is BAD thats why the resistors fail!!!!

I'm sharing my experience after a few repairs not my first repair..

Once you found the resistor open it was a clue that there is an

issue with the vertical circuit..

You need when testing a component is remove it from the pcb or lift one

end of it to test..

The idea of going to the vertical circuit is to check if you need more parts

then a cap kit,If the caps have not been changed before..

Because I know the vertical ic fails and should be address before ordering parts..

Installing a resistor and powering it back up, kinda makes me think you don't

believe me that the vertical is bad...Trust me,I'm trying to help you here

not miss lead you..

It they dont have a .5 watt then get a 1 watt,its only to get a good resistor

not to redesign the circuit..

I find in most case's the Ic is like welded to the heatsink because of

running so hot as the Ic ages and removing it can damage the insulator

and may or may not be able to use it again so the Thermo pad Tp0010 you'll need.

R618 has nothing to do with this repair again you dont judge the resistance

of a part in circuit!!

 

[Ohmerone]

Subscribing. Just got in 3 PGA cabs with kortek vga's in them. One works fine. One has "the aquarium effect" on certain screens/color hues, looks like caps needed. One is dead, but was not dead when bought. Screen was folded over badly, looking like caps, but now dead.

Mike

Do you have a picture of the AE Image to show us

on a fixed pattern and or game play?

 

[m_mcgovern]

Hello Ohmerone-

I have a KT-2914DF that has no video and when powered up I hear a sound like a car's turn signal...where should I start looking?

Thanks!!

 

[Ohmerone]

Hello Ohmerone-

I have a KT-2914DF that has no video and when powered up I hear a sound like a car's turn signal...where should I start looking?

Thanks!!

You want to check the HOT first then the mosfets next..

now if the HOT is shorted emitter to base..Change C724 poor Horizontal drive

can damage the HOT when, Fly and others are good..

Next a Mosfet use high current and likely to fail first..

so check the scan mosfets Q703.06,08 for any one shorted.

sometimes going right to the suspect and be easy and waste less time

defeating shut down or monitoring any voltages ..check these parts also for a short!

Q710.Q713 thats most that would kill the power supply unless the caps

are bad in the power supply,so a cap kit maybe needed too.

Any shorting parts using voltage from the power supply will cause

the power supply to make a CTS..noise..

you have to clear any shorts so the Smps will stop the Car turn signal noise