Author Topic: Kortek KT-2914 is clicking like a turn signal... (Read 13436 times)

nathan118 · « **on:** March 12, 2008, 10:33:12 pm »

Hi guys. My mame cabinet has been working great for a couple years, but I've got a problem. The other day I came home to the arcade monitor making a clicking sound, very similar to a car turn signal, and I could hear the monitor powering on and off. Stupid SMARTSTRIP! It had been a little buggy, but apparently it decided to crap out totally while I was gone all day.

So I get a new powerstrip, a normal one, and when I plug in the monitor, instead of powering up nicely, it proceeds to click like a car turn signal. I put my hand on the glass and there is static, so I assume it's powering up, but I am at a total loss. It's only a couple years old, and I've never had any other problems. It's the Kortek KT-2914 seen here.

http://www.retroblast.com/Hardware/Betson-Imperial-_-Kortek-KT-2914.php

Can anybody point me in the right direction? Is this something I can look into myself, and if not, how do I go about finding a good monitor repair guy in the los angeles area? Thanks so much!

qrz · « **Reply #1 on:** March 12, 2008, 11:06:20 pm »

hmmm, with a cycling smps, i'd be inclined to think there is an increased load on a secondary winding -
either on the main xformer or the flyback. with the flyback secondaries, the most common failure is the vert out ic .
on some brands of tv's, a shorted vert ic will keep the smps from fully pwring up ....
will see if can find a online print for a better idea of this unit's circuitry......

qrz

qrz · « **Reply #2 on:** March 12, 2008, 11:30:02 pm »

found a print at www.retroblast.com/files/KT-XX14X-SM.pdf

not the best rendition , but it will do ...

the unit uses a tda8172 vert output ic . this chip is a common failure on many brands of televisions !

lift one end of r207 ( 1.2ohm 1/2 w) to remove b+ to the ic . attempt to turn on unit . if it does pwr up ,
the ic is likely "toast".

and.....,
the tda9116 appears to be a deflection processor that may negate the above test .

a vert out pulse is one of referenced inputs... a lack of pulse would be reported via sda bus to the syscon ic

if r206 (.47 ohm 1/2w) and r207 are open, a relatively safe bet the tda8172 is bad.
and check d202, c206,c203,c209,c201 and q201 for good measure !

qrz

nathan118 · « **Reply #3 on:** March 13, 2008, 12:07:30 am »

I looked around a little on the board, but I couldn't find the r207 where it was in the schematic. Not sure if I was looking in the wrong spot or if it's underneath something.

I'm getting the feeling this job is way over my head. Can anyone recommend a good place to take it in the Los Angeles area?

nathan118 · « **Reply #4 on:** March 13, 2008, 07:20:40 pm »

Think I'm gonna take it to Betson Imperial where I bought it. Anyone have experience getting stuff repaired there?

qrz · « **Reply #5 on:** March 15, 2008, 06:05:04 pm »

pse post what they find.
would like to know if i was "in the ballpark"

tnx

qrz

Ken Layton · « **Reply #6 on:** March 19, 2008, 12:52:49 pm »

Betson has a location in Buena Park. Is that where you are taking it?

nathan118 · « **Reply #7 on:** March 21, 2008, 12:34:01 am »

Shane_K · « **Reply #8 on:** May 15, 2008, 04:18:02 pm »

(I just posted this in another topic, but I'll copy it here too since they might be the same issue)
http://forum.arcadecontrols.com/index.php?topic=78988.0

Hi everybody

Just wanted to chime in with some info -- I have the Betson Kortek KT-2914 and had the exact same problem after about a week of use. One day when I powered up it was making a tick-tock sound, and sounded almost exactly like a car turn signal, and there was no picture regardless of what I plugged into it. I called Betson (I live in the LA area so I called the nearby shop in Buena Vista Park) and spoke with some service guys there. Unfortunately the warranty on these monitors are very short and because I ordered the monitor long before I had completed my arcade cabinet I was out of warranty already. The guys at Betson were pretty nice about the whole thing and they repaired it for free since I agreed to drive it down there or pay for shipping. When I went back to them to pick it up they told me they had to replace the flyback converter.

About 3 months later the exact same problem started happening again. Plugged it in one day and "tick-tock, tick-tock, tick-tock...", no picture. Unfortunately I had moved to the midwest and was now nowhere near Buena Vista Park to have it repaired.

I've moved back to LA now, but unfortunately my beautiful arcade cabinet has been sitting here unusable for about a year and a half because getting it repaired is so difficult and expensive. I could probably drive it back down to the guys at Betson now to have it repaired but when I called they warned me it would be very, very expensive to repair. The refused to quote me an exact price. Since this thing has died twice now the exact same way, I'm concerned that if I get it repaired the same thing will just happen again.

I wonder how common of a problem this is with arcade monitors?

Rickn · « **Reply #9 on:** May 15, 2008, 07:17:35 pm »

Clicking, hmm... not a fan or familiar with Kortek... after all they are my competition. Too bad the competition does not offer much support.

Anyway a few things with a multi sync, they have a number of relays that switch in and out depending on the resolution of the signal. These switch in various capacitors in the horizontal circuit to match the yoke's impedance with the resolution.

Anyway, disconnect any signal connection does the clicking stop??

Next remove the Horizontal output transistor, now connect a 60 watt light bulb from the collector to ground, if it lights somewhat normal, clicking is gone and B+ seems right, power supply is likely fine.

In that case, suspect the Horizontal output transistor and likely because you mention that it has been fine for a number of years... check, replace all electrolytic capacitors on the main B+ line (Secondary side) that supply the B+ to the HOT collector.

These are all the normal steps but when it comes to a few of these companies that end with Tek and Tec, trhey do not follow good design practise when matching the yoke with the resolutions.

Good Luck
Rick@niemandisplays,com

Shane_K · « **Reply #10 on:** May 19, 2008, 05:16:44 pm »

Hi Rick,

When it's not connected to any video source at all it still makes the same turn signal clicking sound.

I should probably mention that I'm completely inexperienced with capacitors, soldering, etc., and so any instructions like "check capacitor x" are WAAAY over my head. I'm sure if I started tinkering with the hardware myself it would only get worse.

I'm curious then, if this isn't a common problem, what my chances of it happening again are if I get this monitor repaired for the same problem a second time? I hate being so uneducated about arcade monitor inner-workings, but I'm a very busy guy in a professional field and just don't have the time to learn about how to fix this stuff myself (and buy all the necessary tools for it as well). I guess I'll be stuck paying $250 to $500 every time this happens for repairs?

I wish I would have known the warranties on these things suck so badly before I purchased one. I didn't even think to check it!

Shane

Rickn · « **Reply #11 on:** May 19, 2008, 07:47:30 pm »

Hi Shane, not sure what to say..... where are you located??

I am always trying to help and it might be a good idea for you to contact Carl Blessing at All Good Technical Services. he is in Florida and now distributes our monitors but is a very good tech.

Good luck

Rick

Shane_K · « **Reply #12 on:** May 20, 2008, 07:37:34 pm »

I'm in the Los Angeles area. Seems Betson is having a sale on these monitors this month... but I still can't decide if I should repair this one or buy a new one.

If I buy a new one, what would I do with my old one? I don't think I would get very much if I tried to sell a broken arcade monitor. Also, if I buy a new one I'm at risk of getting a monitor with severely squished geometry on the left side (this seems to be a common problem some people are having).

If I repair my current one, I dunno, I just don't trust it after it's died 2 times now.

Shane_K · « **Reply #13 on:** May 21, 2008, 05:01:14 pm »

D'OH! The sale was in March, not May.

Shane_K · « **Reply #14 on:** June 19, 2008, 09:18:59 pm »

Hey everyone, just thought I'd share some useful information...

I took the monitor down to the Betson in Buena Park and they repaired it. When I went to pick it up, I made a point to speak with the tech who repaired it and asked him what the likely cause was. He was very knowledgeable and explained that he had to replace the parts that allow the monitor to switch resolutions because they had been fried (I'm simplifying his answer because the long version was way over my non-technical head). He said that usually he doesn't see this problem in new monitors in perfect condition like mine, usually he sees it in really old monitors that have seen a lot of use and start to have lots of problems with old capacitors wearing out and such. He suspected that in my case the parts that control the resolution of the monitor had been overworked and overheated/fried... he said it could be related to the resolution constantly switching over and over again, like every second. After we talked about it he seemed to come to the conclusion that a lengthy brownout, or multiple quick power failures, or a misconfigured smart-strip could cause something like this. When you first plug the monitor in it adjusts is resolution... so if it was fed just enough power to turn off, on, off, on, off, on... repeat... it might overload or overheat those parts.

This all makes perfect sense to me as to why the monitor has had the same problem twice. The first time the monitor died I had it hooked up to a smart-strip and I must not have adjusted the sensitivity for the auto on connections. This could have fed the monitor unsteady power and caused it to turn on, off, on, off, on, etc... and I never noticed it. The second time the monitor died I was Michigan... I remember the week before it died some storms rolled through and there were quite a few power outages and brownouts according to my neighbors. I wasn't home that week (I was traveling) so I wasn't there to unplug it during the storms. Since the smart-strip was still in use, I suspect a similar thing happened again.

So, lesson learned. My solution was to remove the smart-strip from the equation completely... I purchased a $75 UPS that has automatic voltage regulation to help with brownouts and spikes. This should prevent the same thing from happening again. A word of caution to those who use smart-strips -- be careful! Adjust the sensitivity correctly or just replace them with a UPS. I'm lucky I live near Buena Park.... the repair bill was about $180, and would have been quite a bit more if I had to ship it.

nathan118 · « **Reply #15 on:** November 16, 2008, 09:32:51 pm »

Just to bring people up to date (not that anyone cares) I did finally get my monitor back from Betson West in Buena Park. Cost about $100 to get it fixed (which is better than buying a new one!).

I think my ultimate problem was having it on a smart-strip that went bad, and while I was gone at work it went on-off-on-off all day long for 8 hours. Now the smart-strip is gone, and there is no juice fed to it whatsoever when the arcade is off.

It took over a month to get it fixed, but they seem to have done a fine job. Thanks for all the help.

grantspain · « **Reply #16 on:** November 17, 2008, 07:19:25 am »

i care,glad you got it fixed

ahofle · « **Reply #17 on:** December 08, 2008, 10:07:37 pm »

Well I just started getting the turn signal clicking on my Betson. It's about 1-2 years old.

Do you guys know if I can remove the chassis to have it repaired? Or is the tube necessary? I am nowhere near a Betson location. This is such bad timing as my brothers are coming out for a visit over the holidays. Does anyone know any good repair technicians in the Colorado area?
Any info would be appreciated.

jconstanza · « **Reply #18 on:** December 09, 2008, 03:03:08 pm »

Yes, you can just remove the chassis. I'm sure you can send it out for repair maybe have it expedited. I know Betson doesn't need the tube, they distribute those monitors so I'm pretty sure they have their own "test tube". Sorry don't know of any techs in Colorado.

dacflyer · « **Reply #19 on:** January 08, 2009, 03:56:30 pm »

too am working on a KT-2914F thats doing the turnsignal noise,but it only does it if i have the monitor connected to a sig gen. or video port,
initally the vert ic was shorted and resistors were burned up, i have this all fixed now, but when it is powered up, i only get a raster, no video or OSD.
if i connec the video input..then the set starts clicking. and PS seems to be cycling off and on. any tips ? i have the schematic for this set, but its not the best, when you zoom in, the circuit lines cover the parts id..
i have worked on many other monitors, but this type is new to me.
thanks for any tips,,

dacflyer · « **Reply #20 on:** January 09, 2009, 10:28:25 pm »

hi again.. well i still was working on this monitor,,maybe some of these tips might help you.. after getting the vert. problem fixed, the unit was still having the clicking relay problem, plus i noticed that the 6.3VDC was low, apon checking, the cap right at the swither transformer was open, i replaced this and tried again..the cap is a 47Uf @ 16V
the clicking stopped, i also changed a few other 470's they too were open
might as well recap all the ones coming off the power supply if you going to be servicing a unit, i recomend upgrading to the 105C caps ( hi temp computer grade )
after doing all this, i still had a lousy raster and no video or OSD. i checked my focus and screen voltages, but i noticed when the screen was turned up high for a few min. i noticed a distinctive sound.... HV SPRAY ! , so i turned out the shop lights to see if i could see where it was coming from.. under the yolk!

i suspected a gassy tube at 1st, maybe the yolk, but they do not develope HV spray.
so reluctantly, i removed the yolk, and the rest is history.. the neck was indeed fractured..
i belong to another forum as well and shared my findings with fotos.
feel free to see the link there, i didnlt want to have to retype everything again here..

http://forum.servomagazine.com/viewtopic.php?t=11536

i hope this helps out anyone else thats at the end of their rope with this type of monitor.

dacflyer · « **Reply #21 on:** January 09, 2009, 10:39:29 pm »

BTW the clicking relay that everyone is hearing on this model..that relay is the relay for the degausing circuit..each time the unit resets, it cycles the relay..typical fix for this is checking the vert ic ( unless the resistors are burned open ) theres 2 of them around the vert ic.. one is a .47 ohm, the other is a 1 ohm, all are 1/2 watt
the other causes are bad caps around the main PS. i hope this helps

shilmover · « **Reply #22 on:** August 22, 2009, 07:59:54 pm »

Quote from: dacflyer on January 09, 2009, 10:39:29 pm

BTW the clicking relay that everyone is hearing on this model..that relay is the relay for the degausing circuit..each time the unit resets, it cycles the relay..typical fix for this is checking the vert ic ( unless the resistors are burned open ) theres 2 of them around the vert ic.. one is a .47 ohm, the other is a 1 ohm, all are 1/2 watt
the other causes are bad caps around the main PS. i hope this helps

I have this same problem. Are the vert ics still available?

MonMotha · « **Reply #23 on:** August 23, 2009, 02:31:09 am »

Vert IC is a ST TDA8172. Looks to be EOL.

2 in stock at http://www.bluestar-online.com/TDA8172_p/tda8172.htm?gclid=CIy6q8WTuZwCFSYoawodWw7-ng
I have never heard of these people. Just found them in an ad. There may be a cross somewhere. Part number sounds like something Philips/NXP would have also made.

shilmover · « **Reply #24 on:** August 23, 2009, 08:54:38 pm »

I swapped out the Vertical IC. No difference.

Any ideas?

MonMotha · « **Reply #25 on:** August 23, 2009, 10:42:41 pm »

Pretty much anything that can fail shorted across a main output of the power supply can be a culprit. Vert ICs are common, but diodes on the output of the supply and HOTs are sometimes problems.

shilmover · « **Reply #26 on:** August 31, 2009, 06:05:18 pm »

Quote from: MonMotha on August 23, 2009, 10:42:41 pm

Pretty much anything that can fail shorted across a main output of the power supply can be a culprit. Vert ICs are common, but diodes on the output of the supply and HOTs are sometimes problems.

I have never worked on a monitor such as this... I did get it to display a "no signal" picture the first time, but nothing since.

Can you give me an idea as to where to start?


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Author Topic: Kortek KT-2914 is clicking like a turn signal... (Read 13436 times)

Shane_K

Shane_K

Shane_K

Shane_K

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