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General Category => Amstrad CPC hardware => Topic started by: bjt on 13:15, 12 May 15

Title: Tape head alignment
Post by: bjt on 13:15, 12 May 15
I replaced the drive band inside my 464's tape drive and cleaned the heads with isopropyl. While some games load OK (Amsoft Wordhang etc) others reset the machine mid-way though loading (e.g. Prince of Persia).


I don't think the heads have ever been aligned on this machine since it was new, is it worth trying to change the alignment?
Of course it could just be that the tapes themselves are shot after being in a garage for 20+ years. The surface of the tape looks OK, as far as I can tell.


Everyone likes pics so here's some  ;D


(http://i.imgur.com/HcNWWQ0l.jpg) (http://imgur.com/HcNWWQ0)
(http://i.imgur.com/ENYC4bzl.jpg) (http://imgur.com/ENYC4bz)
(http://i.imgur.com/bIMVhK6l.jpg) (http://imgur.com/bIMVhK6)
(http://i.imgur.com/HnIigpil.jpg) (http://imgur.com/HnIigpi)
(http://i.imgur.com/YYyPQ6Ll.jpg) (http://imgur.com/YYyPQ6L)
(http://i.imgur.com/jvMcRBRl.jpg) (http://imgur.com/jvMcRBR)
(http://i.imgur.com/QgLNPlwl.jpg) (http://imgur.com/QgLNPlw)
Title: Re: Tape head alignment
Post by: Bryce on 14:00, 12 May 15
The PCB is upside-down! The bits may be falling out!

But seriously, yes, you could try tweaking the azimuth to see if they load any better.

Bryce.
Title: Re: Tape head alignment
Post by: roy bates on 15:06, 12 May 15
if you do mess with the tape adjustments do them in very small increments,of say quarter turn or 90 degrees.

clockwise lowers the head,anticlock does the opposite.

but first,run the tape all the way to the end on play first a step in the tape can cause the mess up in loading.
Title: Re: Tape head alignment
Post by: bjt on 12:47, 13 May 15
A bit of fiddling and I managed to get Prince of Persia and Rick Dangerous 2 to load, some other tapes (e.g. AA covertapes) are still having issues. I found that I could only go 180 degrees anticlockwise before the signal was audibly dropping out, and ~270 degrees clockwise before I hit the limit of maximum adjustment. Need to play about with it some more, it seems to be really sensitive to changes.


Looking at the tape head there seems to be some visible wear/scoring, which no doubt doesn't help.


(http://i.imgur.com/2RieUJol.jpg) (http://imgur.com/2RieUJo)
(http://i.imgur.com/Xmxr2LYl.jpg) (http://imgur.com/Xmxr2LY)
(http://i.imgur.com/l825fKbl.jpg) (http://imgur.com/l825fKb)
Title: Re: Tape head alignment
Post by: bjt on 17:11, 14 May 15
Working well now after a bit more tweaking. For anyone else trying this, good luck! It's super sensitive. Seems like 1/16 turn is enough to make the difference between loading reliably and failing intermittently.
Title: Re: Tape head alignment
Post by: Bryce on 17:44, 14 May 15
Congratulations. If it's done using proper equipment (ie: an Oscilloscope), it's a lot less hit and miss to get it right.

Bryce.
Title: Re: Tape head alignment
Post by: Gryzor on 20:54, 14 May 15
Nahhh nothing beats the hand of my 10 year-old self making tiny adjustments for each different loader :D


But seriously, just a few degrees are enough for everything.
Title: Re: Tape head alignment
Post by: alex76gr on 23:36, 14 May 15
I am a spoiled brat because my first computer was a 6128 and i didn't have to fiddle with cassettes! :P
Title: Re: Tape head alignment
Post by: Gryzor on 20:12, 17 May 15
Pfffft you posh kids with your fancy disquettes...
Title: Re: Tape head alignment
Post by: the KING on 21:22, 17 May 15
I just use my Azimuth adjustment package  8)


Azimuth Head Alignment Tape - CPCWiki (http://www.cpcwiki.eu/index.php/Azimuth_Head_Alignment_Tape)
Title: Re: Tape head alignment
Post by: Bryce on 23:51, 17 May 15
I just use my Azimuth adjustment package  8)


Azimuth Head Alignment Tape - CPCWiki (http://www.cpcwiki.eu/index.php/Azimuth_Head_Alignment_Tape)

Pfffft you posh kids with your fancy Azimuth adjustment packages.. :D

Bryce.
Title: Re: Tape head alignment
Post by: Gryzor on 11:29, 23 May 15
Must find mine. For some reason I liked the chopper game :D
Title: Re: Tape head alignment
Post by: llopis on 20:54, 17 August 19
I just use my Azimuth adjustment package  8)


Azimuth Head Alignment Tape - CPCWiki (http://www.cpcwiki.eu/index.php/Azimuth_Head_Alignment_Tape)
I know I'm reviving an old thread, but I'm curious whether that head alignment tape can be re-created from a CDT, or it was authored in special ways (moving the recording up and down I imagine). Anybody knows for sure?