Author Topic: Reset problem... Tallkey CPC ill again.  (Read 584 times)

0 Members and 1 Guest are viewing this topic.

Offline Novabug

  • CPC6128
  • ****
  • Posts: 167
  • Country: gb
  • GX4000 and CPC Videomaker!
    • The Novabug-Blog
  • Liked: 169
  • Likes Given: 128
Reset problem... Tallkey CPC ill again.
« on: 03:15, 22 January 20 »
Evening all,


Apologies if this has been talked about in the forum before, done a search but cannot find the answers I'm looking for.


One of the CPC's I have, my tallkey, original model revision 2 board, seems to have developed another fault. For context, these are the repairs already made.


AY-3-8912 replaced, original was faulty.
Membrane fully cleaned and checked, all internal and external connectors checked and cleaned.
Tape deck rebuilt - replacement belts, replacement idle roller and forward spindle. Motor replaced. Head aligned with Azimuth cassette.
System runs fine using 64k Dk'Tronics expansion with Zaxon DDI3 floppy emulator.
After all these refinements, cassette loading was relatively stable, but not it refused to load most games and resets to BASIC a minute or so into the load. These same cassettes are not degraded or damaged, and run on both my other CPC's, both revision 3 flatkey models.


After cleaning the heads will alcohol, it began to load for longer, but still resets during loading. Approx 8 tapes have been testing such as Dizzy, Mig29, Bronx Street cop, Galactic Plague and more.


I'm pretty certain the head is worn out, and the system is resettiong because of a corrupted read, but I would like to see if anyone else has any ideas or insight into this problem. Thanks guys


My recent loading livestream provides a reference for this issue within the first 30 minutes.



https://www.youtube.com/watch?v=Lf7XfhsvGxs


Thanks in advance

Offline Novabug

  • CPC6128
  • ****
  • Posts: 167
  • Country: gb
  • GX4000 and CPC Videomaker!
    • The Novabug-Blog
  • Liked: 169
  • Likes Given: 128
Re: Reset problem... Tallkey CPC ill again.
« Reply #1 on: 03:17, 26 January 20 »
Nobody have any ideas then? :(


Offline Bryce

  • The Hardware Guy.
  • Supporter
  • 6128 Plus
  • *
  • Posts: 11.602
  • Country: wf
  • It's not broken, it just hasn't been fixed yet.
    • index.php?action=treasury
  • Liked: 4148
  • Likes Given: 433
Re: Reset problem... Tallkey CPC ill again.
« Reply #2 on: 12:47, 26 January 20 »
It could be many things:

- Worn out tape head.
- Bad connection
- Dry joints
- Leaky capacitors

Without looking at the machine with the correct equipment, it's extremely hard to pinpoint the problem.

Bryce.

Offline Novabug

  • CPC6128
  • ****
  • Posts: 167
  • Country: gb
  • GX4000 and CPC Videomaker!
    • The Novabug-Blog
  • Liked: 169
  • Likes Given: 128
Re: Reset problem... Tallkey CPC ill again.
« Reply #3 on: 01:22, 31 March 20 »
Cheers Bryce
Going to start with a replacement read head, do you know, are they standard or do i require the Ae62 which is the code stamped on the head. When i replace it i'll be checking the caps and joints, which i beleive are all fine from past continuity testing.


Offline Audronic

  • 6128 Plus
  • ******
  • Posts: 1.326
  • Country: au
  • I know RST3 . I now know a little More.
  • Liked: 294
  • Likes Given: 663
Re: Reset problem... Tallkey CPC ill again.
« Reply #4 on: 02:11, 31 March 20 »
@Novabug


WARNING:-


If you measure the head for continuity you MUST Magnetically degauss the head.
If you don't then you will damage the tapes that you use.


Ray
Procrastinators Unite,
If it Ain't Broke PLEASE Don't Fix it.
I keep telling you I am Not Pedantic.
As I Live " Down Under " I Take my Gravity Tablets and Wear my Magnetic Boots to Keep me from Falling off.

Offline Novabug

  • CPC6128
  • ****
  • Posts: 167
  • Country: gb
  • GX4000 and CPC Videomaker!
    • The Novabug-Blog
  • Liked: 169
  • Likes Given: 128
Re: Reset problem... Tallkey CPC ill again.
« Reply #5 on: 02:28, 31 March 20 »
I was in the process of buying a demagnetising cassette... would that do the trick?

Offline Audronic

  • 6128 Plus
  • ******
  • Posts: 1.326
  • Country: au
  • I know RST3 . I now know a little More.
  • Liked: 294
  • Likes Given: 663
Re: Reset problem... Tallkey CPC ill again.
« Reply #6 on: 02:36, 31 March 20 »
@Novabug


Yes that would be OK


Ray
Procrastinators Unite,
If it Ain't Broke PLEASE Don't Fix it.
I keep telling you I am Not Pedantic.
As I Live " Down Under " I Take my Gravity Tablets and Wear my Magnetic Boots to Keep me from Falling off.

Offline Bryce

  • The Hardware Guy.
  • Supporter
  • 6128 Plus
  • *
  • Posts: 11.602
  • Country: wf
  • It's not broken, it just hasn't been fixed yet.
    • index.php?action=treasury
  • Liked: 4148
  • Likes Given: 433
Re: Reset problem... Tallkey CPC ill again.
« Reply #7 on: 10:04, 31 March 20 »
It's extremely rare that those heads fail, I would look for other problems before looking for a replacement head.

Bryce.

Offline Novabug

  • CPC6128
  • ****
  • Posts: 167
  • Country: gb
  • GX4000 and CPC Videomaker!
    • The Novabug-Blog
  • Liked: 169
  • Likes Given: 128
Re: Reset problem... Tallkey CPC ill again.
« Reply #8 on: 02:34, 19 May 20 »
So, I have to do some extensive testing, but I have replaced the tape head and things look much better. It's loaded several games even before I have used the azimuth alighnment tape. Will be basically going through half my collection to see if it was a worn out tape head. By the looks of it, the old head clearly has worn scratchs and deep lines on it.

Offline Bryce

  • The Hardware Guy.
  • Supporter
  • 6128 Plus
  • *
  • Posts: 11.602
  • Country: wf
  • It's not broken, it just hasn't been fixed yet.
    • index.php?action=treasury
  • Liked: 4148
  • Likes Given: 433
Re: Reset problem... Tallkey CPC ill again.
« Reply #9 on: 09:41, 19 May 20 »
So, I have to do some extensive testing, but I have replaced the tape head and things look much better. It's loaded several games even before I have used the azimuth alighnment tape. Will be basically going through half my collection to see if it was a worn out tape head. By the looks of it, the old head clearly has worn scratchs and deep lines on it.

Someone may have tried to clean it with the wrong method and damaged the surface. I hope this didn't damage your tapes.

Bryce.