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Time Lord Programmable Delay

Started by Tightpants, May 16, 2015, 09:52:30 AM

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Tightpants

I wasn't going to post this as I thought it was ridiculously overcomplicated. However some folks seem to like that sort of thing so here goes. It's a fully featured programmable PT2399 with tap tempo, presets, tails, rhythmic subdivisions and more. It has a parts count of 260 and it's built on vero!

Instruction manual: https://db.tt/ddOfVkvH
Design overview: https://db.tt/yL0ehFI9
Schematic (audio board): https://db.tt/lZEdN63U
Schematic (control board): https://db.tt/h0MldmBv
Audio board vero layout: https://db.tt/tBa1J0nx
Control board vero layout: https://db.tt/ApkrILHL
Picaxe code: https://db.tt/P9EOZVuo
Bill of materials: https://db.tt/vW3zwTZ3
Video: https://db.tt/wZCidIQ3

I'm happy to help if anyone is mad enough to want to build it (I have built three so far). I will get a better video up when I get some more time - this one just shows the controls in edit mode but you will get the general idea. 

mth5044

You just blew my mind. I had no idea you could get so much use out of a PICAXE. That is awesome, thanks so much for sharing.

Ice-9

Great schematic, and good use of the 4053 switching. Thank you for sharing.
www.stanleyfx.co.uk

Sanity: doing the same thing over and over again and expecting the same result. Mick Taylor

Please at least have 1 forum post before sending me a PM demanding something.

Tightpants

No worries guys, I've learned so much here over the last three years. If I can give a little back then great.

electricco

Great Job !!
I'm with you the Price/Performance consideration ! Good one.

Why not a LCD 16x2 ?... I'm not familiar with the Picaxe but seems similat to atmel chips..



MrBinns

#5
Dude that is sweet! I could listen to you play on that thing all day. 8)

I kinda want to print out the schematics and put them on my wall. lol

Do you reddit? If so definitely post this on /r/diypedals

Tightpants

Quote from: electricco on May 16, 2015, 06:33:18 PM
Great Job !!
I'm with you the Price/Performance consideration ! Good one.

Why not a LCD 16x2 ?... I'm not familiar with the Picaxe but seems similat to atmel chips..



I wanted more of an old school type of feel for the time lord but I did try a 16x2 serial oled on my latest project (programmable analog multiFX). It was easy to use and looks great but boy is it one noisy bugger (perhaps a LCD display would be quieter?). If anybody knows how to reduce noise on these I would be most grateful.
The Picaxe is great, it's cheap and powerful and dead easy to use. It's too slow for direct audio processing but is great for stuff like this. The only major ball ache is that there is no floating point maths.

Tightpants

Quote from: MrBinns on May 16, 2015, 09:54:18 PM
Dude that is sweet! I could listen to you play on that thing all day. 8)

I kinda want to print out the schematics and put them on my wall. lol

Do you reddit? If so definitely post this on /r/diypedals

Thanks fella, I appreciate that, however the wife is not so keen to hear me play I'm pretty much banned from using it in the house these days! I'm not familiar with reddit but will have a look today (I did post it on FSB as well).

UKToecutter

Oh man, that thing is nuts!!!
I'll have to build one, but first I have to lay out a PCB (not a fan of veroboard)
ShumannPLL BOM
Reserve Boards

gena_p1

Looking good, but pt2399 oscillator is very astable, after setting VCO current in about 1 min. it drives it's frequency several %% avay.

Tightpants

Quote from: gena_p1 on May 18, 2015, 04:03:12 AM
Looking good, but pt2399 oscillator is very astable, after setting VCO current in about 1 min. it drives it's frequency several %% avay.

You could be right, I haven't tested it like that. The initial tapped tempo is pretty accurate and I haven't noticed it drifting when playing along to a song but I haven't tested it properly after an interval. I will do some testing and post the results.

Tightpants

Quote from: UKToecutter on May 17, 2015, 06:06:57 PM
Oh man, that thing is nuts!!!
I'll have to build one, but first I have to lay out a PCB (not a fan of veroboard)

It is quite a challenge on vero so I was thinking of doing a pcb layout and maybe getting some made if there is enough interest. I did try to get a single sided layout so I could etch my own but never finished it - it was getting quite difficult so I think a double sided layout would be better (I don't have much experience with pcb making). I will upload the source files (Express .sch) if anybody wants to have a go as well.

Tightpants


Tightpants

"Looking good, but pt2399 oscillator is very astable, after setting VCO current in about 1 min. it drives it's frequency several %% avay."

Tap tempo test - I left it running for a couple of minutes at the end to see if it is stable and it seems OK to me. It's upside down for some reason & apologies for the heavy breathing!
https://youtu.be/yqxX0B0FlpY

markolomew

If someone ends up fabricating a PCB of this, I'd love to pick one up.

ElectricDruid

Quote from: Tightpants on May 16, 2015, 09:52:30 AM
I wasn't going to post this as I thought it was ridiculously overcomplicated. However some folks seem to like that sort of thing so here goes. It's a fully featured programmable PT2399 with tap tempo, presets, tails, rhythmic subdivisions and more. It has a parts count of 260 and it's built on vero!

Instruction manual: https://db.tt/ddOfVkvH
Design overview: https://db.tt/yL0ehFI9
Schematic (audio board): https://db.tt/lZEdN63U
Schematic (control board): https://db.tt/h0MldmBv
Audio board vero layout: https://db.tt/tBa1J0nx
Control board vero layout: https://db.tt/ApkrILHL
Picaxe code: https://db.tt/P9EOZVuo
Bill of materials: https://db.tt/vW3zwTZ3
Video: https://db.tt/wZCidIQ3

I'm happy to help if anyone is mad enough to want to build it (I have built three so far). I will get a better video up when I get some more time - this one just shows the controls in edit mode but you will get the general idea.

That's frankly amazing!

A couple of queries though - if you had a PICAXE in the circuit, why did you do the footswitch debouncing and the Mode Select with so many 4013s? There's large sections of that control circuit that are screaming "Turn me into firmware! Turn me into firmware!" at me! ;)

The 4053 for bypass takes me back though...I once did that on a LM13700 SVF-based wah pedal I built some many years ago. There were problems with the circuit, but that part wasn't one of them. It was quiet and reliable. In those days, people wanted "noiseless switching" as the holy grail, not "true bypass".

Anyway, nice work. Tap tempo on the PT2399 isn't an easy thing.

Tom

Tightpants

Quote from: ElectricDruid on October 04, 2015, 04:51:21 PM

That's frankly amazing!

A couple of queries though - if you had a PICAXE in the circuit, why did you do the footswitch debouncing and the Mode Select with so many 4013s? There's large sections of that control circuit that are screaming "Turn me into firmware! Turn me into firmware!" at me! ;)

The 4053 for bypass takes me back though...I once did that on a LM13700 SVF-based wah pedal I built some many years ago. There were problems with the circuit, but that part wasn't one of them. It was quiet and reliable. In those days, people wanted "noiseless switching" as the holy grail, not "true bypass".

Anyway, nice work. Tap tempo on the PT2399 isn't an easy thing.

Tom


Thanks for that Tom, 
I'm interested in controlling analog effects by digital means and this project was my first attempt at getting to grips with the technology - sort of a test bed. I know it is overcomplicated but hopefully some people might find some useful info in the write-up.
I used the hardware debounce because I couldn't get reliable results with software, probably just my crap code but the soft touch switches I was using seemed to bounce forever.
The mode select was done like that to save I/O pins on the Picaxe. I could have used a LCD or OLED display but I seem to like doing things the hard way!
Cheers,
Pat     

Tightpants


DIY Bass

OK, this look svery interesting, and my son is after a Delay at present, so this could be a go.  Earlier in the trhread you posted the schematic CAD files, but they are not there anymore.  Are you able to post them again?  I would probably look at doing up a board rather than using vero.

Tightpants

Quote from: DIY Bass on March 11, 2018, 12:42:02 AM
OK, this look svery interesting, and my son is after a Delay at present, so this could be a go.  Earlier in the trhread you posted the schematic CAD files, but they are not there anymore.  Are you able to post them again?  I would probably look at doing up a board rather than using vero.

See my last post above, I couldn't find a way to edit the original post so I posted all the files again yesterday. Have fun  :)