JamHamster
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jamhamster.bsky.social
JamHamster
@jamhamster.bsky.social
940 followers 38 following 1.2K posts
Nerd, tinkerer, lunatic.
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It got a bit complicated with that and an interrupt as well so I went for the simpler route. 🙂
I'll swap it with an attiny85. It only needs a couple of pins. ☺️
Well, that's much smaller, I'll need to do some programming next. ☺️
The PCB is little more than a breakout board for the attiny and hall effect sensor but should definitely do the job.

Into the tub it goes. ☺️
Oh yeah, about that pause detection.

The full Arduino is overkill but the attiny doesn't have hardware serial which is needed for snappy pause response from the Bluetooth module.

Luckily there's a gpio pin on the module that pauses if you short it to ground.

I'll need a PCB for this. 🤔
Played component Ker-Plunk and stripped out everything that wasn't completely necessary without sacrificing performance.

I got it down to a cap, switch, coil and pot.

I'm a happy old Hector. ☺️
Found one game that was problematic but used another tap file and it was fine so I'm calling this done.

it prefers a square wave but is happy with sines too. ☺️
The RoboCop 3 loader is positively demonic. 😲

Worked though! 🥳
I've built the changes into a cassette with pause detection and I haven't found anything that doesn't load.

It's adjusted so that full volume favours the leading edge for the Speccy and half evens up the waveform for the 64.

time for some proper testing I think! ☺️
Filtered out the remaining HF noise and distortion, it's rock steady! 🥳

I've used a pot in line so that it creates a high pass filter with the DC blocking cap. Most things load fine but it boosts the leading edge for certain Speccy speed loaders. I'll add a boost switch later. ☺️
Coupled some coils back to back, yellow is the tx coil, blue is the Rx coil. There's a low frequency sag caused by the transfer that's just enough to cause a trigger event.

It's bang on exact but the Speccy doesn't work as well as it should.

My guess is that it's flooding the Datacorder. 🤔
Made up a batch of hot swap coils and a test frame that's half storage, half synth.

You very kind internet people have given me a bunch of tricky loaders to test with so I'm going to do a bunch of observational legwork for a bit. 🤔
That actually worked pretty well. It helped dial in a couple of things too, cheers! 🙂
You're the second person to mention pavloda, They're definitely going on my list. I also have a few decks I can try, thank you! 🙂
This is great stuff, thanks! 🙂
Thank you kindly! I'm having far too much success so thought I'd make life harder for myself. ☺️
Hello!! I'm working on a tape loader device type thing and I want to give it something tricky to chew on.

What are the trickiest loaders fo the C64 and Speccy? I'm currently loading StrangeLoop and Sanxion without issue and I'm after a challenge.

Suggestions gratefully received! 🙂
I will never not watch this all the way through. 😊
Nice!! I've been doing a bit of loader tinkering lately and as long as it crosses 0v reliably and the timing is okay, it should work. Some laptop amps are a bit poor at rendering a square wave effectively. Have you tried scoping it? 🙂
I've set up the pauseable tape with the new config and I'm loading games at random.

The magic formula is to have enough coil turns to match the amps output across the main frequencies, filter the high end a smidge, and attenuate until the datasette head can cope. Easy peasy really. 😂
Results are in. Tap2Wav beats TapClean in consistency. The TapClean output volume is all over the place whereas Tap2Wav works to a set level.

I've tuned the tape and have been flipping through wavs, they all look good so far!

Even TapDancer works! 🥳
I was wildly wrong about HF noise, it was the head ringing all along. A huge chunk of ferrite proved that nicely.

I'm converting the entire C64 TOSEC tap library to see which is the most consistent at outputting a wav then I'll do some proper tuning. ☺️
It was hard enough to get mass produced tapes to load in mono. ☺️
It loads games at a distance of 1 Avengers Batman box (45mm) so I'm not surprised it's ringing. 😂
It's a different story for the ZX Spectrum, it yums up pretty much anything.
I need to tune the coil turns, DC blocking cap and distance to find a happy medium. 🤔
It likes a square if the volume is low. It's an ugly signal but it works.

The signal from the coil is pristine but it looks like the datasette head has inductive ringing which would explain a lot. 🤔