PET AUDIO DATA LOADING THINGY
Project time!
Get a Datasette that you are happy to break apart and perhaps render useless.
What we want to do is remove the PCB - this is pretty much all we need. The case, the tape mechanism; everything else, the whole lot is redundant.
Extract the board as in picture one.
1) This is the tape switch sensor. All the tape buttons when pressed move a bar, which depresses this switch and so tells the PET something has been pressed. The PET can’t actually tell which button has been pressed, only that one has.
2) There is a grounding wire at this corner of the PCB - be careful not to damage or remove. You need to lie this along and under the board so that it joins the wire bunch going into the board.
I had problems with interference when starting this - this ground wire seemed to help
3) This red and black wire was attached to the motor. I taped these out the way, but if inclined you could use these to operate a switch and LED to show things were working. Its not required, but it would look nice.
4) This is the play/record head. We go in to the board through the yellow wire which all meets up.
5) This is the yellow wire that we strip back, to give us left and right channel and ground. Left and right are visible when you take the deck apart; to get to ground you have to cut into it until the wire is visible.
6) This is the erase head.
When you have the board out and you remove everything you don’t need you then connect everything through the yellow wire. You eventually end up with the picture below.
As long as the play button is taped to ‘on’ - and everything works you can then box it all up. I stuck mine in an old joystick box I had.
As far as testing then you need a PET wav file - which you can find on the PET page.
I found I needed to alter the audio slightly from that, that is produced from say the WAV-PRG software.
I use a MacBook and I use Audacity. I load the file up and increase gain to the maximum (+36db) - Volume from the Mac side is one or two notches from the top.
And that it - in the end its a really simple wee hardware project that takes the pain out of running software on the PET - especially if you don’t have disk drives.
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