The Sinclair QL Forum

bwinkel67 wrote: Mon Jun 02, 2025 2:33 am

stephen_usher wrote: Wed Jun 24, 2020 10:08 pm A conversation on the QL Facebook page got me wondering how easy it would be to get the digitised sound of a microdrive running to play when the vDrive was accessed.

A long time ago I bought Johan Engdahl's little device to add sound to my vDrive. I sounded pretty bad:

https://youtu.be/JbBH4GgZxsM?t=466

Is there a way to reprogram that device (it has a USB connection) with your code? I recall seeing a YouTube video of yours where the sound was perfect.

Which Sound device, I only know about Stephen's original version.

Derek_Stewart wrote: Mon Jun 02, 2025 7:33 am Which Sound device, I only know about Stephen's original version.

https://www.sellmyretro.com/offer/detai ... unit-47527

bwinkel67 wrote: Mon Jun 02, 2025 7:55 am

Derek_Stewart wrote: Mon Jun 02, 2025 7:33 am Which Sound device, I only know about Stephen's original version.

https://www.sellmyretro.com/offer/detai ... unit-47527

Thanks, I must of missed that one.

What do the edge connector plug into?

This was my original prototype. You can see the speaker I'm using.

https://youtu.be/VhUG1TIi_j8

When the speaker is put into the Microdrive enclosure that becomes a sound box for it so you get some of the lower frequencies.

Derek_Stewart wrote: Mon Jun 02, 2025 9:06 am What do the edge connector plug into?

I think that's for reprogramming it. To install it you solder some wires to the vDrive circuit board.

bwinkel67 wrote: Mon Jun 02, 2025 2:33 am
A long time ago I bought Johan Engdahl's little device to add sound to my vDrive. I sounded pretty bad:

https://youtu.be/JbBH4GgZxsM?t=466

Is there a way to reprogram that device (it has a USB connection) with your code? I recall seeing a YouTube video of yours where the sound was perfect.

Ah!
Yeah! For that reason I have posted in your video. So it was you
I think it is not due to programming (or it is),
I am trying to convert that sharp thing based on freq into a wave (DAC) with some caps an resistors in order to make the curves restructured.
Not easy (long time without doing something like that, decades probably).

Just I wanted to be sure it was not my mistake, and now with your feedback and others (recently some also told me unsuccessful same goal).
By now it is only 1 person seems to got it. Thus he has the key.

Also I was studying the schema... it seems to me to do not be right, the capacitor is between +5v and +5v? I think it is a typing mistake. The signal is a square, no way it could be a digitalized sound, but perhaps that would be my mistake (for a fuse or who knows thing, that I couldn't reprogram).

The Attiny takes more than 10 seconds (with my board Digispark or direct powered) to start the sound, not usable at all, in 10 seconds the microdrives has finished the reading, so led activity.

In any case, it has a lot of lack of info.

stephen_usher wrote: Mon Jun 02, 2025 12:02 pm This was my original prototype. You can see the speaker I'm using.

https://youtu.be/VhUG1TIi_j8

When the speaker is put into the Microdrive enclosure that becomes a sound box for it so you get some of the lower frequencies.

Hi,
Thanks for answering Stephen,
Probably my mistake, but exactly how do you program this Digispark Attiny?
How do you put this transistor into the Digispark?

Trying to replicate this you show in the video but ... with different speakers of 8 Ohms (even others), same capacitors (even others) I cannot get that sound in anyway.

Checking it with the oscilloscope I can tell that the wave cannot be something "sweet" at all, but sharp and metallic.

Thanks

Edit: you have already answering me by U2B, long time to remember details. That is logical. I will try to figure it out with what you have share in your github.

I don't have a "Digispark" ATTiny, I just use a DIP Atmel ATTiny85 chip. The LED output turns on the transistor which regulates the power to the chip, so the ATTiny85 chip powers up and starts working almost instantly.

This is the version made with a proper PCB.

Here's it in action, and it shows the speaker in more detail (Sorry about the half coughs, I had bad hay fever at the time.): https://youtu.be/A9s6XKbfVUY?si=YxysALuTFVFqtwi0

stephen_usher wrote: Mon Jun 02, 2025 3:45 pm I don't have a "Digispark" ATTiny, I just use a DIP Atmel ATTiny85 chip. The LED output turns on the transistor which regulates the power to the chip, so the ATTiny85 chip powers up and starts working almost instantly.

This is the version made with a proper PCB.

IMG_2421.jpeg


Here's it in action, and it shows the speaker in more detail (Sorry about the half coughs, I had bad hay fever at the time.): https://youtu.be/A9s6XKbfVUY?si=YxysALuTFVFqtwi0

Hi

Do you have Gerber files to make more PCBs

Derek_Stewart wrote: Mon Jun 02, 2025 4:25 pm Hi

Do you have Gerber files to make more PCBs

Yes, on the github repository: https://github.com/stephen-usher/vDrive-Sound-Board