The NEW Build Your Own Arcade Controls

Main => Monitor/Video Forum => Topic started by: infrared on December 06, 2017, 03:36:08 am

Title: Help identifying this monitor - Kortek
Post by: infrared on December 06, 2017, 03:36:08 am
Hello to all,

please i need help to identifying my arcades cabin monitor. Monitor is 19" and i have sparking problem in the high voltage where the yellow circle is in the picture.

The only thing the board has is the mark Kortek but no model

Any help appreciated

Regards
Michael
Title: Re: Help identifying this monitor - Kortek
Post by: Ken Layton on December 06, 2017, 11:34:13 am
Probably a KT-1420A. Perhaps this guide will help:

https://docs.google.com/viewer?a=v&pid=sites&srcid=ZGVmYXVsdGRvbWFpbnxtdHBhY2lmaWNvfGd4OjdmM2Y3ODY2Yjc0ZDFkNjg

Lots of my other guides are here:

https://sites.google.com/site/mtpacifico/kens_korner
Title: Re: Help identifying this monitor - Kortek
Post by: infrared on December 10, 2017, 04:53:56 am
Ken thank you for your answer.

If you see at the picture i posted the big cap in the top right position of my board says it is C602 / 680uF but the manual of  KT-1420A says it is C601 / 0.01uF ceramic.

That's why i am almost sure it is not KT-1420A

Title: Re: Help identifying this monitor - Kortek
Post by: Ken Layton on December 10, 2017, 01:01:53 pm
Probably the Penn-Ray version:

http://www.arcade-museum.com/manuals-monitors/PennRay%20KT510A%20monitor%20manual.pdf (http://www.arcade-museum.com/manuals-monitors/PennRay%20KT510A%20monitor%20manual.pdf)

You have to remember that sometimes you need to use a combination of ALL the different versions manuals to troubleshoot these monitors.

Imperial versions:

http://www.arcade-museum.com/manuals-monitors/Imperial%20KT1420A%20monitor%20manual.pdf (http://www.arcade-museum.com/manuals-monitors/Imperial%20KT1420A%20monitor%20manual.pdf)

http://www.arcade-museum.com/manuals-monitors/Imperial.pdf (http://www.arcade-museum.com/manuals-monitors/Imperial.pdf)

Tekbilt version:

http://www.arcade-museum.com/manuals-monitors/Tekbilt%20Monitor.pdf (http://www.arcade-museum.com/manuals-monitors/Tekbilt%20Monitor.pdf)

Wico SUM20 Videomaster version:

http://www.arcade-museum.com/manuals-monitors/Wico%20SUM-20C.pdf (http://www.arcade-museum.com/manuals-monitors/Wico%20SUM-20C.pdf)

Some KT-1420 variations may have either a 560 uf main filter capacitor or a 680 uf main filter capacitor installed. It's whatever they had handy during the production run.
Title: Re: Help identifying this monitor - Kortek
Post by: infrared on December 11, 2017, 03:42:16 am
You are right,
the Penn-Ray version is propably the board i have and with that i will try to repair mine.
I want to thank you for your help Ken, i really appreciated.

Regards Michael
Title: Re: Help identifying this monitor - Kortek
Post by: Ken Layton on December 11, 2017, 12:06:43 pm
In regards to the arcing of the flyback, you should carve up the flyback cage as described in my repair guide to allow more breathing room for the flyback. Then clean off the area of the flyback where the arcing was coming from with household spray cleaner (I like to use Mean Green), then swab the area with 99% isopropyl alcohol. Now glob on some clear silicone glue over that area and let dry. This should eliminate the arcing and allow you to run the monitor normally.
Title: Re: Help identifying this monitor - Kortek
Post by: infrared on December 11, 2017, 03:02:37 pm
I do exactly what you said and the problem fixed. No sparking any more.

The only thing i have now is with the horizontal width coil. Then screen width is expanded over the screen and with the coil i can do a little things.
I changed the coil from another same board and i also changed the cap C414 (434/200=.43uF/200V). No luck. I tried bigger cap 0.47.uF and after 0.56uF.
The problem insists.
Title: Re: Help identifying this monitor - Kortek
Post by: infrared on December 12, 2017, 01:48:41 pm
Finally fixed.

The problem is that the JC jumper (Red small wire with black connector) has two modes. N=Normal, W=Wide.
The jumper was in wide mode and for that the horizontal coil cannot reduce the screen so long.
When i put it in normal mode the screen reduced and made possible to adjust with the horizontal coil.
Now the monitor is perfect with correct colors, width and height

See image 1 in yellow circle
and finally the second image with monitor running a game (the image is not best because  i am not good to take photos)

I have repaired a lot of pinball machines (www.firepower.gr (http://www.firepower.gr)) but it was my first attempt to repair a cabin with monitor problem.

I want to thanks again Ken Layton for his help.

Regards
Michael
Title: Re: Help identifying this monitor - Kortek
Post by: infrared on December 26, 2017, 04:22:59 am
Hello again  Merry Christmas and a happy new Year.

Suddenly today the monitor starts to display like this (see photo).
I think this is a vertical collapse but i don't know where to look in the schematic.
Is it possible to give me a tip where to look and what components is more common to fail ?

Regards
Michael
Title: Re: Help identifying this monitor - Kortek
Post by: Ken Layton on December 26, 2017, 09:42:16 am
First place I'd look is to see if you've broken either the Vertical Height pot or the Vertical Hold pot. They are very delicate and can break easily.

Next look at the two vertical output transistors Q201 and Q202. They are both bolted to the flyback cage. Both are also type 2SD1138 (this type is also used on Electrohome G07 monitors).

Next check the integrated circuit IC401.
Title: Re: Help identifying this monitor - Kortek
Post by: yotsuya on December 26, 2017, 01:27:44 pm
First place I'd look is to see if you've broken either the Vertical Height pot or the Vertical Hold pot. They are very delicate and can break easily.

Next look at the two vertical output transistors Q201 and Q202. They are both bolted to the flyback cage. Both are also type 2SD1138 (this type is also used on Electrohome G07 monitors).

Next check the integrated circuit IC401.

Ken,

To piggyback off the OP (and my apologies, but it is related to the same exact monitor PCB) I have this monitor, and the fuse at FS01 has been blowing. I replaced the HOT bottle cap as well as some transistors and resistors, and I still get the same thing. The flyback has a pinhole I patched with epoxy and I did the cage cutting mod. Any suggestions?
Title: Re: Help identifying this monitor - Kortek
Post by: infrared on December 27, 2017, 12:48:21 pm
I do not know what is going on!!!
I chech every cap,resistor and i change the ic 401 and the first time i power up the monitor works fine.
After 2 hours i power up the monitor and same thing vertical collapse.
I will try tomorrow to change q201 and q202 even if i test as ok.
Title: Re: Help identifying this monitor - Kortek
Post by: infrared on December 29, 2017, 01:33:51 pm
Finally i change Q201, Q202 and monitor know works fine.

Ken do you know in case i need a flyback in the future where can i buy one.
Title: Re: Help identifying this monitor - Kortek
Post by: Ken Layton on December 29, 2017, 10:27:48 pm
Check with Chad at ardacecup.com for a flyback.
Title: Re: Help identifying this monitor - Kortek
Post by: PL1 on December 30, 2017, 01:48:10 am
ardacecup.com
Pretty sure Ken meant to say arcadecup.com (http://arcadecup.com/).   ;)


Scott
Title: Re: Help identifying this monitor - Kortek
Post by: infrared on December 30, 2017, 02:18:05 am
Thank you Ken and a happy new year.


Title: Re: Help identifying this monitor - Kortek
Post by: infrared on January 22, 2018, 02:59:40 pm
Because i need the schematics to help me repair my board (KT510A) and to do that i must look into 3 different documents i finally created the layout and the logic diagram from scratch.
I think that this layout-logic diagram will probably help also the owners of Kortek 1420A, Tekbit or Imperial

Please keep in mind that this creation is based to my board it is a first beta version and perhaps has errors.
I have check every connection and every type of component to prevent errors.
If an error has found please post it so i can repair the document.

Board Layout: http://www.firepower.gr/downloads/Kortek%20KT-510A%20Layout.pdf (http://www.firepower.gr/downloads/Kortek%20KT-510A%20Layout.pdf)
Logic Diagram: http://www.firepower.gr/downloads/Kortek%20KT-510A%20Logic%20Diagram.pdf (http://www.firepower.gr/downloads/Kortek%20KT-510A%20Logic%20Diagram.pdf)
 
Regards
Michael
Title: Re: Help identifying this monitor - Kortek
Post by: Ken Layton on October 24, 2018, 12:46:15 am
Finally I changed transistors Q201, Q202 and monitor now works fine.


The vertical output transistors are mounted to the flyback cage. Many times when one transistor goes bad, it affects the other one too. So if you suspect a bad vertical output transistor, replace them both at the same time. Here is a picture of them.
Title: Re: Help identifying this monitor - Kortek
Post by: Ken Layton on October 24, 2018, 12:55:09 am
Hello to all,

please i need help to identifying my arcades cabin monitor. Monitor is 19" and i have sparking problem in the high voltage where the yellow circle is in the picture.

The only thing the board has is the mark Kortek but no model

Any help appreciated

Regards
Michael

Updating this thread. He has the Kortek KT-510A also known as Penn-Ray model 17-0214 (13" version) and 17-0220 (19" version). This model has two large aluminum heat sinks attached to the sides of the chassis. The heat sink on the left is the B+ regulator (2SC1629A transistor or 2N3055 transistor bolted to it). The heat sink on the right is the horizontal output transistor (2SD900B bolted to it).
Title: Re: Help identifying this monitor - Kortek
Post by: Ken Layton on October 24, 2018, 01:20:14 am
One problem this model (KT-510A) and the KT-1420A have is with the high voltage shutdown circuit keeping the monitor from powering up. If you have recapped it and that didn't get it powered up, there are two other items to check:

1. The high voltage shutdown pot (R415, labeled as "X-Ray" on the board). Sometimes the glue used to seal the pot makes the pot go bad internally. It's a 5k trimpot and here is where you can get it:

https://www.arcadepartsandrepair.com/store/monitors/5k-ohm-trimmer-potentiometer-p1014/ (https://www.arcadepartsandrepair.com/store/monitors/5k-ohm-trimmer-potentiometer-p1014/)

2. The zener diode D401 (located directly to the left of the integrated circuit) may have gone "leaky". Unsolder and lift one end of it and re-power the monitor. Does it power up now? If so, check that diode out of the circuit for an electrical leaky condition. The manual and schematic call out this diode as type 05Z12Y which in reality is a 12 volt @ one watt zener diode. You can use a type 1N4742A or an NTE142A diode to replace it.
Title: Re: Help identifying this monitor - Kortek
Post by: Keith15My password is ale on September 21, 2019, 11:48:08 pm
I have just obtained one of these machines. After checking the board and thinking it was Penn Ray 501-a board realized there were subtle difference . I found this thread and identified that it is identical to the board here. The monitor Is dead, with no tube glow. I pretty quickly identified the  C602 capacitor is bulging and therefore suspect. the fuse  F602 has blown and ther is no B+ voltage. Does anyone have any suggestions to whether or not what component failures may be a good start for me to check before I get started on properly diagnostic testing ?