Korg Forums Forum Index Korg Forums
A forum for Korg product users and musicians around the world.
Moderated Independently.
Owned by Irish Acts Recording Studio & hosted by KORG USA
 
 FAQFAQ   SearchSearch   MemberlistMemberlist   UsergroupsUsergroups   RegisterRegister 
 ProfileProfile   Log in to check your private messagesLog in to check your private messages   Log inLog in 

My Original Kronos Is Dead-Nothing @ Power On.
Goto page Previous  1, 2
 
Post new topic   Reply to topic    Korg Forums Forum Index -> Korg Kronos
View previous topic :: View next topic  
Author Message
AntonySharmman
Approved Merchant
Approved Merchant


Joined: 16 Oct 2010
Posts: 3585
Location: Hellas

PostPosted: Fri Jul 26, 2019 1:28 am    Post subject: Reply with quote

voip wrote:
... and see if the auto power off option is available .My Kronos X later model has it.

Your Korg arranger have it for sure , Kronos OS had never such an option as generally any computing device
without electronic Power ON/OFF switch !
_________________
Music Conductor - Sound Engineer & Developer - Automotive SMPS/RF R&D - Electronics Engineer
PaSeries Demos - WavesArt.eu - KorgPa.gr <> Facebook

Keyboards : Steinway-D, Kronos X, Pa5X 76, Pa4X 76, Montage M7 , Roland-XV88, Emu3,Emax II,Synclavier II,Yamaha DX Series, ΟΒ-8V
Back to top
View user's profile Send private message Send e-mail Visit poster's website
GregC
Platinum Member


Joined: 15 May 2002
Posts: 9451
Location: Discovery Bay (San Francisco Bay Area)

PostPosted: Fri Jul 26, 2019 2:03 am    Post subject: Reply with quote

AntonySharmman wrote:
voip wrote:
... and see if the auto power off option is available .My Kronos X later model has it.

Your Korg arranger have it for sure , Kronos OS had never such an option as generally any computing device
without electronic Power ON/OFF switch !


I vaguely recall this discussion from 7 or 8 yrs ago. Dan Phillips may have posted.

Something to the effect that Korg had to comply with country rules- where power off feature is a country requirement.

So we have K's with it, some without.

But something tells me that Korg later did something permanent about auto power off at some time.

Sorry, this sounds confusing. Its my recollection and might be off target.
_________________
Kronos 88. MODX8
Achieve your musical dreams Smile
https://soundcloud.com/user-898236994
Back to top
View user's profile Send private message Send e-mail
mm-pro
Full Member


Joined: 29 Dec 2002
Posts: 200
Location: Portland, Maine USA

PostPosted: Fri Jul 26, 2019 2:56 am    Post subject: Reply with quote

I would never turn it on in any case.
_________________
Korg Gear: (2) Kronos, PS3100, (2) MaxiKorg, PE1000, Z1Ex, MS20M,(2) OASYS-PCI, Synthe Pedal, Wavedrum WD-1, Prophecy, SQ1, 2600FS, M3M
Back to top
View user's profile Send private message Visit poster's website
voip
Platinum Member


Joined: 27 Nov 2014
Posts: 3758

PostPosted: Fri Jul 26, 2019 9:25 am    Post subject: Reply with quote

AntonySharmman wrote:
voip wrote:
... and see if the auto power off option is available .My Kronos X later model has it.

Your Korg arranger have it for sure , Kronos OS had never such an option as generally any computing device
without electronic Power ON/OFF switch !


Not all Kronos' have it, but on my Kronos X, there is a small motorised pusher on the main power switch that is used to automatically turn off the power. If this has been activated, the switch requires extra force to overcome the mechanism and turn on the Kronos.

In my case, I've disabled auto power off in the Global menu.

.
Back to top
View user's profile Send private message
AntonySharmman
Approved Merchant
Approved Merchant


Joined: 16 Oct 2010
Posts: 3585
Location: Hellas

PostPosted: Fri Jul 26, 2019 10:42 am    Post subject: Reply with quote

voip wrote:
Not all Kronos' have it, but on my Kronos X, there is a small motorised pusher on the main power switch that is used to
automatically turn off the power. If this has been activated, the switch requires extra force to overcome the mechanism and turn on the Kronos.
In my case, I've disabled auto power off in the Global menu.

If you're sure about this , I have no reason to doubt since I own only Kronos 1 & 2 , but this function requires for sure hardware components that do not exist in K1 & 2.

On the other hand the existence of a motorized/servo system for such an easy operation is totally insane , this function is always achieved by ST-BY function of
PSU via Mosfet controlled by OS and sometimes like in PaSeries , an extra Electromagnetic Relay is used but in all cases main ON-OFF mechanical switch ,
always override this function , this is the rule in designing such a feature.
_________________
Music Conductor - Sound Engineer & Developer - Automotive SMPS/RF R&D - Electronics Engineer
PaSeries Demos - WavesArt.eu - KorgPa.gr <> Facebook

Keyboards : Steinway-D, Kronos X, Pa5X 76, Pa4X 76, Montage M7 , Roland-XV88, Emu3,Emax II,Synclavier II,Yamaha DX Series, ΟΒ-8V
Back to top
View user's profile Send private message Send e-mail Visit poster's website
NormC
Full Member


Joined: 09 Jun 2015
Posts: 158

PostPosted: Fri Jul 26, 2019 6:50 pm    Post subject: Reply with quote

My 2015 K2-73 has the auto off power switch.
_________________
Kronos 2 73
Back to top
View user's profile Send private message
mm-pro
Full Member


Joined: 29 Dec 2002
Posts: 200
Location: Portland, Maine USA

PostPosted: Sat Aug 03, 2019 12:55 pm    Post subject: Reply with quote

Kronos failed again with the new power supply. Not sure what to try next.
_________________
Korg Gear: (2) Kronos, PS3100, (2) MaxiKorg, PE1000, Z1Ex, MS20M,(2) OASYS-PCI, Synthe Pedal, Wavedrum WD-1, Prophecy, SQ1, 2600FS, M3M
Back to top
View user's profile Send private message Visit poster's website
GregC
Platinum Member


Joined: 15 May 2002
Posts: 9451
Location: Discovery Bay (San Francisco Bay Area)

PostPosted: Sat Aug 03, 2019 1:08 pm    Post subject: Reply with quote

mm-pro wrote:
Kronos failed again with the new power supply. Not sure what to try next.


I read your 7/25 post above that you fixed your K

?

Is it now DOA ? Or intermittent ?
_________________
Kronos 88. MODX8
Achieve your musical dreams Smile
https://soundcloud.com/user-898236994
Back to top
View user's profile Send private message Send e-mail
mm-pro
Full Member


Joined: 29 Dec 2002
Posts: 200
Location: Portland, Maine USA

PostPosted: Sat Aug 03, 2019 1:26 pm    Post subject: Reply with quote

Worked fine for a week with the new power supply. I am guessing either there is an intermittent problem and the power supply was fine, or that whatever caused the first power supply to fail has caused a second to fail as well.
_________________
Korg Gear: (2) Kronos, PS3100, (2) MaxiKorg, PE1000, Z1Ex, MS20M,(2) OASYS-PCI, Synthe Pedal, Wavedrum WD-1, Prophecy, SQ1, 2600FS, M3M


Last edited by mm-pro on Sat Aug 03, 2019 1:28 pm; edited 1 time in total
Back to top
View user's profile Send private message Visit poster's website
mm-pro
Full Member


Joined: 29 Dec 2002
Posts: 200
Location: Portland, Maine USA

PostPosted: Sat Aug 03, 2019 1:28 pm    Post subject: Reply with quote

No lights, no fan, no screen. The green light on the motherboard comes on.
_________________
Korg Gear: (2) Kronos, PS3100, (2) MaxiKorg, PE1000, Z1Ex, MS20M,(2) OASYS-PCI, Synthe Pedal, Wavedrum WD-1, Prophecy, SQ1, 2600FS, M3M
Back to top
View user's profile Send private message Visit poster's website
GregC
Platinum Member


Joined: 15 May 2002
Posts: 9451
Location: Discovery Bay (San Francisco Bay Area)

PostPosted: Sat Aug 03, 2019 2:12 pm    Post subject: Reply with quote

mm-pro wrote:
No lights, no fan, no screen. The green light on the motherboard comes on.


as you can tell, its guess work here.

Going down the list is mobo, SSD

Getting expensive
_________________
Kronos 88. MODX8
Achieve your musical dreams Smile
https://soundcloud.com/user-898236994
Back to top
View user's profile Send private message Send e-mail
qayqaywsx
Junior Member


Joined: 15 Mar 2009
Posts: 81

PostPosted: Mon Aug 05, 2019 2:20 pm    Post subject: check the voltage Reply with quote

Hi

DISCLAIMER : BE CAREFUL WITH WORKING ON POWER !!
DONT TOUCH ANYTHING WHICH IS POWERED

you should try to check the voltage of the power connector after switching the kronos on : put the multimeter to V ac switch it on and measure wether there are 230V or 110V (depending on your countries power).

if there is no power there can be many reasons for this behaviour (short circuit dead mb ...)

If i remember the inner things from original kronos right , there is a fuse in the main power cable. Possibly burned ?
Switch defctive ?

good luck
Back to top
View user's profile Send private message
KK
Platinum Member


Joined: 13 Oct 2016
Posts: 1416

PostPosted: Tue Aug 06, 2019 2:17 am    Post subject: Reply with quote

After this new failure, start with the basics. How stable is the power where you plug your Kronos, do you always use an UPS with it, etc. In one of my older PCs, three or four power supplies toasted one after the other, even though no other computer or appliance in the house ever did. Cause was for some reason it was particularly sensitive to the slightly unequal power in the house. Even if you live in a big city (or not), never assume the electric company gives you clean power. Always plug your unit on an UPS. Basic line filtering is sometimes not enough.

Of course, there could be many other causes as well. An intermittent short can end up damage a power supply. The Kronos is a complex machine and there are also several enable levels/lines controlling the PCBs and main ICs for different purposes. Any one of them can stop everything as a protection. A voltage slightly too high or too low on any of those lines and a whole circuit or more stops waiting for the correct signal. Unless you are at ease with this complicated stuff, I would send it to a qualified tech or Korg recommended service place.
_________________
Shhh  My Kronos 7 Cool
Back to top
View user's profile Send private message
mm-pro
Full Member


Joined: 29 Dec 2002
Posts: 200
Location: Portland, Maine USA

PostPosted: Tue Aug 06, 2019 3:58 am    Post subject: Reply with quote

I do use a UPS. I suspect a short. I imagine it will take me some time to find it.
_________________
Korg Gear: (2) Kronos, PS3100, (2) MaxiKorg, PE1000, Z1Ex, MS20M,(2) OASYS-PCI, Synthe Pedal, Wavedrum WD-1, Prophecy, SQ1, 2600FS, M3M
Back to top
View user's profile Send private message Visit poster's website
AntonySharmman
Approved Merchant
Approved Merchant


Joined: 16 Oct 2010
Posts: 3585
Location: Hellas

PostPosted: Wed Aug 07, 2019 10:01 am    Post subject: Reply with quote

You might need an expert technician to examine deeper this case or authorized Korg service center !
Kronos Enhance ENO-1612 120W that you have replaced as all PC PSU have a ST-BY input and a ST-BY output voltage of 5V that feeds
mobo ST-BY control stage.
When PSU input voltage goes low (<0.5V) then a mosfet transistor enables PSU and feeds all peripheral circuits including mobo and Kronos boots.
If this PSU ST-BY input voltage is unstable or permanently in low state then PSU do not output any voltage and mobo do not boot !
This SMPS PSU do not suffer by any fluctuation , sparkles or over voltage of net power and has over current protection in summary current flow of outputs.

There are 2 cases of malfunction if there is no any semiconductor short circuit case (that I strongly doubt) :
- PSU has been electrically burned (usually switching mosfets/diodes) with usual initial symptom , burned fuse of PSU board !
- Motherboard ST-BY control output stage is malfunctioning and do not enable control pin of PSU (clear indication by green mobo led)
or has another serious damage and diagnostic logic gates do not allow PSU to power on.

Technician must ground PSU input terminal manually overriding and disconnecting mobo control output and come to a conclusion of the issue there !
My guess , it's the second case , since you have already replaced PSU !

Both cases in nowadays are treated as whole board circuit replacement , very few people have the required knowledge
due to repair the actual failure components.

Good luck
_________________
Music Conductor - Sound Engineer & Developer - Automotive SMPS/RF R&D - Electronics Engineer
PaSeries Demos - WavesArt.eu - KorgPa.gr <> Facebook

Keyboards : Steinway-D, Kronos X, Pa5X 76, Pa4X 76, Montage M7 , Roland-XV88, Emu3,Emax II,Synclavier II,Yamaha DX Series, ΟΒ-8V
Back to top
View user's profile Send private message Send e-mail Visit poster's website
Display posts from previous:   
Post new topic   Reply to topic    Korg Forums Forum Index -> Korg Kronos All times are GMT
Goto page Previous  1, 2
Page 2 of 2

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum


Powered by phpBB © 2001, 2005 phpBB Group