Trying Repair Original XVI Power Supply...

[Dhampird]

Hello, finally i get a XVI CZ-634C-TN from Japan, i could try it with the original source for a while, after less a hour the computer dont boot up, i used a AC converter:
IN>AC 220V 50HZ
OUT>AC 100V 58W

Below the XVI the sticker says:
100V  50/60 Hz (41W and MAXIMUM 99W)

Like i said, the computer worked perfect like an hour, after that the computer didnt Turned ON more, then i opened original PSU, and i and I've seen follow problems:

1. in some capacitors i could notice a little fluid capacitor leak below themselves.
2. 125V 4A Fuse was burned
3. Little burned area near Diode Zener Z32
4. NPN Transistor Q31 (2SC2333) seems burned (located later)

After locate that problems i changed all capacitors for new ones with same values, i changed diode Z32 (RD4.3EB 4.3V Zener) and also i placed a new 125V 4A  fuse, when i tried ON the PSU again, the results are:

- fuse burned again when i switch ON.
- New Diode Z32 seems burned also after power ON.
- New capacitors seems no problems.

More later i located NPN Transistor Q31 (2SC2333) was broken, i tested with polimeter using continuity position and follows continuity in all ways, seems broken. For for more security i replaced all this that follows:

-Same new Capacitors instaled first try(seems ok).
-New 125V 4A Fuse (again)
-New Diode Z32 (RD4.3EB 4.3V Zener) (again)
-PC31, PC51 (2 TLP521-1 OPTOCOUPLER Transistors)
-Q32, Q33, Q53 (2SC1815Y NPN Transistors)
-NPN Transistor Q31 with equivalent NPN BUX-84 ( i didnt find yet a 2SC2333, i´ll get that)

After i tried and now the Fuse is not blow once i turned ON, but after a while like 10 minutes, the fuse will blow and near Zener a little spark appear, i´m wondering if the problem will be that i use NPN BUX-84 instead 2SC2333. After this test Diode Z32 is burned again, probaly Q32 also is burned (i think so) and  NPN BUX-84 is burned, Resistors seems ok.

I´m trying to repair the Original XVI PSU, i know that i could try ATX mod, but i dint find a mini MICRO ATX Psu that fits into Original X68000 PSU case for now, also i read about ITX mod, anyways i´ll great to know how repair the Original PSU, i read a Japanese page about X68K PSU repairs:

http://x68k.net/x68dengen/

, but is not specific for XVI models, i found it some different components in my XVI PSU and  i´m looking for more detailed info with complete XVI PSU components related in any web, but i didnt find some like that. Please if anyone can help would be helpful.

I think that i´m near to solve the problem, please , would be helpful if someone could give me a help to their own experiences.

Thanks.
Regards.

[caius]

Hello, finally i get a XVI CZ-634C-TN from Japan, i could try it with the original source for a while, after less a hour the computer dont boot up, i used a AC converter:
IN>AC 220V 50HZ
OUT>AC 100V 58W

The problem is that you used a AC converter which can absorb MAXIMUM 58W while your X68000 XVI may require  up to 99w...

[Dhampird]

Hello, thanks for reply, i believed that with an  AC 100V 58W transformer will be enough because the XVI label tells about: 41W MIN. and MAX.99W, probably in real use with PSU conected to hardware (floppy drives ac, mainboard,etc) will be necessary more W. up to 99W or more. Anyways, i tried the PSU repair outside the case without devices conected (no consumption in watts), then i´m wondering that with only 100V 58W transformer the PSU should work anyways. I dont know that, but if there is no W. consumption with that 58W of stepdown converter the PSU should work alone, with  nothing devices conected to it.

Ok, probably i´m wrong with related above, anyways i found a  220V>100V Stepdown converter with 500W, compatible with PS3 and XBOX360, i think that use it will be  perfect for the XVI once all hardware is conected to the PSU. I didnt find anyone with 120W or little more, only 500W.

Please tell me your opinion about if I using 100V 58W transformer hooked  to PSU (without any devices conected to it (alone)), PSU XVI should work if the min. required by computer is 41W and is nothing conected to the PSU? I´m trying to know if the problem should only the W. in Stepdown 220V>100V converter (need more) or if there is another important problem in any PSU components.

Thanks a lot again for help and reply.
Regards.

[caius]

Hi,  how can you repair or test the PSU if it's not connected to anything and so the load is zero?If the PSU has no load ,his watt consumption is zero.
I will proceed so: the original PSU is probably gone and you should spend a lot of time tracking down the problem and repair it.So, I would replace it with a new PSU (mini ATX are fine ) and try it (with all connected:motherboard, floppy, etc..) using this time a step-down converter with more than 99w and see if all is ok.If not, probably you damaged also the motherboard (in this case check first  electrolitic capacitors).Let me know what do you think about.
Ah, I forgot: follow this great guide to replace PSU, it's for all X68000 models:

http://nfggames.com/nfg/x68repair/

[netwalka]

Collapsed tantal capacitor make a short circuit.

That may cause a problem.

First, try to change all the tantal capacitor with new one.

One of my friend who fixed his PSU told me.

"Try to gather and change every part on the PCB with new one at the same time. Everything at the same time.

Before that's done, never plug in the power. It will ruin all you did until now"

ATX/ITX method is good enough and I did it, too.

But... I guess it is a last resort.

[Dhampird]

Hello, thanks for replies, i think that i´ll try both methods, be great try repair original PSU and also try mini ATX or ITX method. About:

caius

Hi,  how can you repair or test the PSU if it's not connected to anything and so the load is zero?If the PSU has no load ,his watt consumption is zero.

I though try the PSU alone from computer first to try check voltages in Floppy PSU conectors and mainboard PSU conector to know if really goes voltage to that conectors after change capacitors and another components, this was the idea to try test the PSU alone from computer, to know if the voltages go through the conectors after Turn ON with the switch.

So, I would replace it with a new PSU (mini ATX are fine ) and try it (with all connected:motherboard, floppy, etc..) using this time a step-down converter with more than 99w and see if all is ok

About try mini ATX the problem is that i dint find a mini ATX PSU that can fit into the original X6K PSU, find it will be great because i need aditional space to install CF Card and SCSI to IDE adapter. Most of mini ATX PSU are more large than original PSU and occupy the space reserved for internal SCSI hard disk, i read about ITX mod, this fits internally original PSU and use also a external AC. You mentioned about "using this time a step-down converter with more than 99w" but i´m confused with that, i mean, if i use a ATX mod i think only that i need is that new PSU have  more than 100W, and the PSU could be  directly conected to 220V, and then i avoid the stepdown, then could i get a 220V ATX PSU more than 100W and with invertor IC mod will work? or i need to get a 100V ATX PSU and use also the Stepdown? I mean than in my country i have 220V and if i use ATX method should avoid the stepdown trouble?

Is there any other important consideration to know with ATX method?, i  have here a 220V ATX PSU with follow specs



Then i could try the invert IC mod like show here:



After that conect the ATX to 220V should work, right? I should try first this with external ATX to check if there is no damage in the XVI computer, capacitors mainboard  and base board seems be fine.

After check if the ATX mod works i think the best option will be use ITX method (more than 100W and run with external Ac 12V normaly) or find a mini-micro ATX power supply that fit into PSU original case and runs with 220V and more than 100W. Also i saw another power supply device called PicoPSU ATX but i dont know if the inverter IC mod works with it.

netwalka

Collapsed tantal capacitor make a short circuit.

This is the problem, i dint find a list of all original PSU components to try buy them and replace it, please if you know any web with all XVI PSU components listed needed please tell me. For now i changed all electrolitic capacitor with new ones and the parts that i located are burned, i unknow if the tantal capacitors are bad, anyways will be great to locate all listed components to try future repair, but first i´ll try ATX test and after ITX that fits into PSU case, i think this is the fastest way.

If you know a ITX model that fits without problems into original PSU case, please let me know, or what model of mini micro ATX do you use.

Thanks a lot for replies.
Regards.

[caius]

I though try the PSU alone from computer first to try check voltages in Floppy PSU conectors and mainboard PSU conector to know if really goes voltage to that conectors after change capacitors and another components, this was the idea to try test the PSU alone from computer, to know if the voltages go through the conectors after Turn ON with the switch.

But if put no load on the PSU, then you will obtain zero Volts when you measure it  with the multimeter, I presume.

About try mini ATX the problem is that i dint find a mini ATX PSU that can fit into the original X6K PSU, find it will be great because i need aditional space to install CF Card and SCSI to IDE adapter. Most of mini ATX PSU are more large than original PSU and occupy the space reserved for internal SCSI hard disk, i read about ITX mod, this fits internally original PSU and use also a external AC. You mentioned about "using this time a step-down converter with more than 99w" but i´m confused with that, i mean, if i use a ATX mod i think only that i need is that new PSU have  more than 100W, and the PSU could be  directly conected to 220V, and then i avoid the stepdown, then could i get a 220V ATX PSU more than 100W and with invertor IC mod will work? or i need to get a 100V ATX PSU and use also the Stepdown? I mean than in my country i have 220V and if i use ATX method should avoid the stepdown trouble?

Yes, sure, if you put a MICRO-MINI 220V ATX you don't need anymore the step-down converter.

[Dhampird]

Ok, thanks any important to know about AMPERES from ATX PSU related to signals +5V, +12V -12V and +5VSB?

[Dhampird]

I tried ATX PSU mod follow above diagrams and the XVI works Perfect, now i´ll need to find a micro mini ATX that fits into PSU original case,  any model micro mini ATX PSU sugestions¿?

Thanks  a lot.

[netwalka]

I tried ATX PSU mod follow above diagrams and the XVI works Perfect, now i´ll need to find a micro mini ATX that fits into PSU original case,  any model micro mini ATX PSU sugestions¿?

Thanks  a lot.

How about this thingy....

http://windom1.trustpass.alibaba.com/productgrouplist-101692344/power_supply.html

[eidis]

 Maybe this schematic will help:

http://web.archive.org/web/20050516141450/http://homepage3.nifty.com/nyan_world/data/x68kps.pdf

P.S. Lawrence, could you please add this pdf to the WiKi ?

I found some interesting links as well. Check it out:

http://ockeysprogramming.blog42.fc2.com/blog-entry-518.html

http://garakuta.homelinux.org/~nosuke/diary/201004.html

http://garakuta.homelinux.org/~nosuke/diary/diary.html?y=2010&m=4&d=25&n=0&x=5&a=1&mode=comment

http://x68k.net/diary/200203.html

Best of luck !

Eidis

[Dhampird]

Hello, thanks a lot for replies and thanks EIDIS for the fully info links, i´ll hope find a way to repair the original PSU, i´m waiting for some parts that i bought ,probably arrival soon, but like the ATX mod worked with an old ATX PSU that i conected external to XVI, first i´ll try CF mod, i have to build SCSI 26PIN to 50PIN cable, also i have here a Yamaha V769970 adapter and a SD-CF-IDE-A adapter with black PCB and leds, i think is the same like you have viewing some photos about your installs. Anyways if i get original PSU works again i´ll post here results. Also i Found a mini Mikro ATX PSU that i think fits perfectly into original PSU case, i´m waiting seller answer about how much W. can handle this mini mikro ATX PSU:

http://cgi.ebay.es/ws/eBayISAPI.dll?ViewItem&Item=310287889426&Category=65505&_trkparms=algo%3DLVI%26its%3DI%26otn%3D2

Thanks a lot  again.

[Dhampird]

Hello, well,  i tried again to repair original PSU XVI, i have the PSU alone from X68K, not conected, i´m using 220V to AC 100V 58W adapter to ty it, i know that i have to get another with 100W or more, XVI sticker said: 100V  50/60 Hz (41W and MAXIMUM 99W) then i think with 58W adapter i can try to test for some seconds, when i get the XVI and i conected to this 58W adapter the PSU worked well about 1 hour, then the fuse blow.

After replace all capacitors for new ones and Diode Zener Z32 i tested the PSU with 58W power supply adapter and after turned on with PSU switch result is:

-the FAN didnt work and after ten seconds the fuse was burned in front of me.

I checked again the components and i noticed that the Fuse  Z32 after that test is again burned and also i noticed that 2SC2333 transistor is damaged, then i changed:

-Same new Capacitors instaled first try(seems ok).
-New 125V 4A Fuse (again)
-New Diode Z32 (RD4.3EB 4.3V Zener) (again)
-PC31, PC51 (2 TLP521-1 OPTOCOUPLER Transistors)
-Q32, Q33, Q53 (2SC1815Y NPN Transistors)
-NPN Transistor Q31 NEC 2SC2333 ( i tried also with equivalent NPN BUX-84 but didnt work, after some time the fuse blowed again)

After that, i turned ON and now nothing happen, i mean that the fuse maintain normal, the FAN no works but the fuse is working normal, no burned again, voltage seems ok.

I´m wondering if i´m in right path, i´ll have to know if the FAN is normal that didnt work  if the PSU is working alone from computer, only i´ll have to try with a 100W or more stepdown converter but i think only 58W stepdown converter that i have is more than necessary to try first repair tests the PSU. Please if anyone know tell me what you think about the FAN, if be normal that this dont work if the PSU is working alone from mainboard.

Thanks a lot.