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General Category => Technical Support - General => Topic started by: imacman on 20:20, 30 April 20

Title: 6128+ works but weird functioning
Post by: imacman on 20:20, 30 April 20
Hello,


my "new" machine seems to be ok but i can play burning rubber with no issue but when i want to play a disk , i can do "cat"
i load a prog then "disk missing" sometime it loading but not untill the end sometime it reboot....
i have changed the disc belt (the old one was out).


I have check the IC16 on pin 7 and Pin 14 and i find 2.80v in basic mode and 2.30v in GX mode. (i have read in an other post that the value must be 4.75v and 5v) so maybe this is the pb...


I use the genuine monitor the 5v output is 5,25v


i hope it's comprehensive.
thanks for your help!
Title: Re: 6128+ works but weird functioning
Post by: Bryce on 08:15, 01 May 20
Try cleaning the contacts on the power socket and power switch first.

Bryce.
Title: Re: 6128+ works but weird functioning
Post by: imacman on 10:22, 01 May 20
Thanks for your reply,


i have cleaning the contacts but it's the same , same value on the pin , even the values have gone down... (1.90V), the value of the belt motor is 4.70v..
i don't think my floppy disk drive is not dead but really weird....


i will find to try another tip...


Franck.
Title: Re: 6128+ works but weird functioning
Post by: Bryce on 11:30, 01 May 20
If it's only the drive that's causing problems then it could be two things. Either you didn't clean the belt wheel properly and there is still some black gunk on them. Or the drive needs to be calibrated.

I would ignore the voltage test at the moment, you must be testing it wrong somehow. If IC16 really only had those values the CPC definitely wouldn't start or run Burning Rubber.

Bryce.
Title: Re: 6128+ works but weird functioning
Post by: imacman on 16:14, 01 May 20
i have recleaned the  two wheels belt... it's the same  :(  .


i think it's a calibration problem , i have made a short video to see the problem...


so the cat command is ok but the -run"disk - don't work...
https://www.youtube.com/embed/fWI1ICY-BX0 (https://www.youtube.com/embed/fWI1ICY-BX0)

Title: Re: 6128+ works but weird functioning
Post by: Bryce on 18:50, 01 May 20
Yup, most likely out of calibration or the disk is faulty, but if it's doing this on more than one disk then it needs to be calibrated.

Bryce.
Title: Re: 6128+ works but weird functioning
Post by: imacman on 19:44, 01 May 20
thanks for your reply...
unfortunatly i can't do this i need to find somebody who can do this  :D


hope i will find


Franck
Title: Re: 6128+ works but weird functioning
Post by: Bryce on 08:27, 02 May 20
I can do this if you send it over (to Germany).

Bryce.
Title: Re: 6128+ works but weird functioning
Post by: imacman on 17:37, 02 May 20
Quote from: Bryce on 08:27, 02 May 20
I can do this if you send it over (to Germany).

Bryce.


Hi Bryce,
i send you a PM.
Thanks
Title: Re: 6128+ works but weird functioning
Post by: Bryce on 11:10, 11 May 20
This morning the drive from @imacman (https://www.cpcwiki.eu/forum/index.php?action=profile;u=3720) arrived and due to the lucky coincidence that the "healing bench" is empty and I'm stuck at home, it got looked at straight away. It had an issue that I haven't seen before, so I thought I'd post about it.

I did the usual service things you do - Reflowed the solder joints on the headers (some were in fact cracked), checked that all the gunk had been removed from the old belt (mainly, but there was still some residue), check the RPM (was fine) and checked the head was properly calibrated (also fine), but the drive as imacman stated could still CAT any disk, but couldn't load anything. After some watching of what it was doing, I decided that the stepper (head position) motor might have an issue. Took it apart, but it's fine too. Then I noticed that the head was vibrating at a certain point as it travelled toward the inner tracks. I thought the frame might be misaligned (dropped perhaps), but that was fine too, so I decided it needed a complete disassembly and re-build. That's when I discovered that the head rail (that shiny bar that the head moves along) was really sticky in the middle. There are holes in the drive frame which exposes this bar to the other side where the belt is. The sticky stuff is most likely from whatever cleaner was used to clean the belt gunk. After cleaning and greasing the bar (and putting it all back together) the drive now works perfectly and it's a lot quieter too :) So the lesson here: If you are cleaning the wheels while swapping the belt, don't get any cleaner into that hole, otherwise you'll make the head rail sticky and it will ruin your day.

Bryce.


Title: Re: 6128+ works but weird functioning
Post by: ComSoft6128 on 12:08, 11 May 20
Thanks for this @Bryce (https://www.cpcwiki.eu/forum/index.php?action=profile;u=225)
As you know I'm not a hardware guy but I always find posts (with pics!) like this one interesting. You should start making videos :D
Title: Re: 6128+ works but weird functioning
Post by: imacman on 12:20, 11 May 20
Great work great pictures... as ComSoft6128 i'm not a harware guy and it's very interesting !!
thanks
Title: Re: 6128+ works but weird functioning
Post by: Bryce on 13:43, 11 May 20
Quote from: ComSoft6128 on 12:08, 11 May 20
Thanks for this @Bryce (https://www.cpcwiki.eu/forum/index.php?action=profile;u=225)
As you know I'm not a hardware guy but I always find posts (with pics!) like this one interesting. You should start making videos :D

I did consider videos, but from a "time to make vs. useful information" ratio, they're rarely worth it. I'm more a pictures person. If anything, I'd write a book (with pictures).

Bryce.
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