Odd Moving Warble on Tape

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dhoggan
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Odd Moving Warble on Tape

Post by dhoggan »

Apologies in advance if I've put this in the wrong place - it was a 50-50 between here (as it might be hardware) and one of the software sections.

A wee while ago I went through all my Acornsoft tape titles and sorted out those that load. Given that fact that I've collected them from various sources over the past few years, I was surprised that the majority loaded first time with only a handful failing. Since I'm using an Acorn data recorder I've also sat through the loading of all the games - working and not - so have become familiar with the sound.

I recently picked up a new title and have been trying to get it to work, with odd results. The first odd thing is that it usually fails to load, but not always in exactly the same place. For example, around blocks 05-07 seem a common place on the loader, along with block 1E of the game data. When it works, it sounds like you'd expect, but when the issue occurs,it sounds like that tape is slowing down, or at least struggling to keep the right speed. Rewinding alone does not seem to fix the issue, but forward winding a bit then rewinding can often get the block to be reread correctly.

I can't see any obvious physical damage to the tape which isn't really surprising since the tape can play through OK (well, maybe once or twice).

I was automatically going to assume the tape deck is OK as it plays all other tapes consistently - including those I made by converting UEF to WAV - but I'm wondering if a combination of old tape drive belt and sticky mechanics in the tape shell might be an issue? I've ordered a new belt anyway,

Has anyone come across this kind of odd "warble" before that can be present or ocassionally not?

Thanks,

Dave
Model B Issue 7 - Dual Gotek/5.25"; IFEL Sideways board; RetroClinic Co-Pro; VideoNuLA
Master 128K - Gotek; RetroClinic Co-Pro, CF HDD & DualOS

Main interest: BBC computer languages
Coeus
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Re: Odd Moving Warble on Tape

Post by Coeus »

This kind of thing also happens with audio tapes and it hard to know where the fault lies. On one player, some tapes can play fine, others not and the tapes that seem like they may be faulty play fine elsewhere.

If you were trying to create a digital copy there are some tricks. If you have access to one, you could try playing it on a double-captan cassette deck. These are less susceptible to imperfections in the tape transport inside the cassette shell. You can also transplant the tape from a sticking shell into a working one.

I guess the double-capstan cassette deck could be use for daily operation but transplanting the tape isn't very authentic. See what happens when you fit the new drive belt.
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dhoggan
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Re: Odd Moving Warble on Tape

Post by dhoggan »

The replacement tape belt for the ANF03 arrived today from Dataserve Retro and has been fitted but I'm now having an issue where nothing plays!

Having a look at the rollers, it seems that the belt keep slipping out of the groove on the large black roller and rides on the lip of the roller. Having a look the new belt it wider than the original, but does fit completely in the roller's groove, so not sure why it keeps slipping out.

Any ideas?

Thanks,

Dave
Model B Issue 7 - Dual Gotek/5.25"; IFEL Sideways board; RetroClinic Co-Pro; VideoNuLA
Master 128K - Gotek; RetroClinic Co-Pro, CF HDD & DualOS

Main interest: BBC computer languages
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