Loading a program to my Minstrel 3

[Moggy]

I played the WAV through audacity,media player and a couple of other audio programs and it sounded perfect, the correct pitch just a little clipped but certainly correct speed/pitch etc.

It's audio properties are 11025 Hz mono PCM which is neither compressed or 22050 Hz as you are suggesting.

Your WAV on the other hand definitely sounds like fast load and is running at 16000 Hz,so not sure what you are doing or how you arrived at such a bit rate.

[8008guy]

No luck so far. I tried the LunarCorps at a bunch of different sound levels. Tomorrow I will put the logic analyzer on the Minstrel and see if I am getting audio to the input circuits.

Thanks for everyone's help. Hope to get this solved.

len

[TMAOne]

It's not often I disagree with Mark but as audio is my bag I would say this WAV is very mechanized ,lacking as it does the usual aural artifacts

I think it's me you were disagreeing with Moggy, so Mark's reputation is intact. And I am confused.

This is your test file.

It is what I expect from an automated process like WinTZX. Clean and perfect.

But here is the original poster's file:

I was mistaken. It is "clean". Yet it is not "perfect". i.e. each bit is NOT composed of identical perfect peaks and valleys, yet each 0 bit in its entirety is identical to every other 0 bit, and the same for 1's.

Perhaps this utility has stored two sample bits that came originally from analog, and is simply exhaling them in the correct sequence and number to make the desired .wav? I don't know; I haven't looked at the code itself.

I use WinTZX also, and it seems to have disappeared from the Net. I've put the distribution file of the latest version I have, into my dropbox at https://www.dropbox.com/s/r7p9mxa7hdww5 ... d.exe?dl=1 for anyone who wants to download it.

[1024MAK]

What! Who woke me up?

I’ve not looked at any of the audio files, let alone commented!

@8008guy - The original ZX80, ZX81 and ZX Spectrum computers all require an audio ‘volume’ level that is near the limit, or greater than the limit of most current consumer ‘headphone’ / ‘earphone’ outputs.

If your Minstrel 3 is using 74HCxxx chips, it will need an even greater audio ‘volume’ level. So you will need an audio amplifier.

If you have an old set of PC amplified speakers that have a quarter inch (¼“) headphone socket, and suitable cables/adapters, this will do. Cheap eBay audio amplifiers based on the LM386 chip should also work. E.g. this one (2PCS LM386 Module 20 Times Gain Audio Amplifier Module F Raspberry Pi Arduino) from eBay.
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LM386 Module

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Power it from a +9V or +12V supply NOT a +5V supply rail.

Mark

[mrtinb]

My experience from the TZXduinio I've built is. If the output voltage is 5V it will load. If it is below, it will not load.

[Moggy]

@ Mark

Moggy promises never to post after consuming more scotch than is good for him!

@TMAone

To be honest in my less than sober state I didn't look at the file magnified and yes you are right there is an element of analogue and "best guess" in it which P2WAV has introduced and may explain why I never had any joy with it.

I tried this WAV on real 81 and got no joy at any level nor with emulator also any WAV created with wintzx and another conversion program I have,whilst perfect for the spectrum I cannot get to work with the 81 I also noticed that the usual couple of seconds buzz present on real zeddy programs is absent and wonder does the 81 use this as say a level setter or timing device?

Many thanks too for the wintzx dropbox jobby as my copy has gone AWOL.

@8008guy

Did you try the short test WAV I posted? This works on real 81 and emulator and being short and sweet wastes little time.

Finally agree totally re output level, line level even pro level won't cut it and Marks suggestion re speaker headphone socket is an excellent one.

[8008guy]

@8008guy

Did you try the short test WAV I posted? This works on real 81 and emulator and being short and sweet wastes little time.

Finally agree totally re output level, line level even pro level won't cut it and Marks suggestion re speaker headphone socket is an excellent one.

No, did not load.

I built using HC.

I'm back to the TZXduino for a minuet and it's doing some loads, though not successful yet. After the .p file runs it does sometimes return to a text screen filled with junk.

Should most programs auto run? I am in the "L" mode.

[8008guy]

I had a success with a program I recorded to tape and then played back. I need to look at the signal with a scope and see what the P2P voltage is. I know on the speaker it is LOUD!!!

Now I know everything works.

len

[Moggy]

Good to hear of progress.

In my experience the "L" cursor signifies what I would call half a load. in other words it hears it yet not well enough to load correctly so would say you are on your way.

I'm not surprised the Minstrel recording is loud using as it does ZX80 type components. if you ever compare a ZX81 recorded WAV to a ZX80 one you will notice the 81 is only fairly loud with the odd bit of hiss and buzz thrown in whereas the ZX80 recording is very loud, and before I statrted using a ZXpand with my 80 I found it more reliable than the 81 re load/save when using tape.

[8008guy]

Ok, I've had success with the TZXDuino! I bumped the voltage on the 386 to 9 volts. I now get better than 7V PTP, like I saw on the cassette recorder.

Thanks for everyone's suggestions!

len