O.T.L.A. (high speed loader) works for me too !

Any discussions related to the creation of new hardware or software for the ZX80 or ZX81
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zx80nut
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O.T.L.A. (high speed loader) works for me too !

Post by zx80nut » Wed Sep 07, 2011 12:47 am

By building a simple circuit to ensure a clean loud signal is transfered to the ZX81 (a comparator operating with a bit of hysteresis) I have also successfully managed to get OTLA working VERY well.

It works with my ZX80 clone, with the ZX81 conversion on it. I will check on the ZX81's but there is no reason why it shouldn't work.

So far, I can reliably get the 11025bps transfer speed.

So, the bigger programs such as Manic Miner loads in 11.5 seconds and 3D Monster Maze in 10.5 seconds !

I may be able to get the full speed 14700, but I haven't tried tweaking the circuit - it was a quick 5-minute knock-up on a solderless breadboard with crocodile clips connecting the jack plugs!

I have seen elsewhere on this forum that it has been said that the window interface is not very good and that it is not easy to convert .P to .WAV files.
Sorry, but I have to disagree - once I have used it a couple of times, it's actually very easy to use.
From the File Menu, Select "New+Add". Select the ".P" file, click OK on the next box then click "Play" - that's all you need to do to play a ".P" file into the soundcard. So, just a few clicks needed to get the .P file to the ZX81.
Alternatively, just click "SBB => WAV" to convert it quickly to a WAV.


There's even a "batch" option to convert .P to .SBB then .SBB to .WAV


...I'll publish the tape input cleaner circuit that I knocked-up shortly if anyone is interested.


Regards.


Grant.

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Paul
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Location: Germanys west end

Re: O.T.L.A. (high speed loader) works for me too !

Post by Paul » Wed Sep 07, 2011 7:48 am

zx80nut wrote:...I'll publish the tape input cleaner circuit that I knocked-up shortly if anyone is interested.
Regards.
Grant.
Thanks a lot. Yes, we are definitely interested :!:

Will it be neccessary to have different settings for different speeds?

Regards.
Paul
In theory, there is no difference between theory and practice. But, in practice, there is.

sirmorris
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Re: O.T.L.A. (high speed loader) works for me too !

Post by sirmorris » Wed Sep 07, 2011 7:52 am

This sounds great!*

I may be tempted to try a tape now and again...


*pun courtesy of Chuddleight & Chuddliegh, master punners to royalty 1887-1937

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Andy Rea
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Re: O.T.L.A. (high speed loader) works for me too !

Post by Andy Rea » Wed Sep 07, 2011 7:55 am

Me too, i did play with it a little but since i have ZXpand the motivation for building an audio conditioner wasn't really there for me, mostly because my analog design skills are pretty poor :oops:

Thanks in advance

Andy
AFK

diskman
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Joined: Tue Apr 02, 2019 9:23 pm

Re: O.T.L.A. (high speed loader) works for me too !

Post by diskman » Fri Feb 14, 2020 8:03 pm

I know Im replying to a 9 year old thread... Any chance you have the circuit for your hardware amp?? lol. Wishing..

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