#712

There’s no problem from me :slight_smile: They are very simple and quick circuits to make. I was actually thinking of putting each Roll (6,5,4,3) on 1 board, instead of as separate small boards, but prefer to continue working on the missing Osmond files circuits.

The reason I did the PCB’s was because I didn’t want to mess with physical Paper Circuits and couldn’t understand why Peter hadn’t released PCBs, even after he put the Osmond files on the site for anyone to use. So the PCB’s are identical duplicates to Peters because I used his Osmond files. All I did was duplicate the top layer, so they became 2 layer, 2 sided boards instead of 1 layer 1 sided boards. I didn’t alter the designs or schematic in any way. I also shared this info to everyone, so they could do themselves. Like an open source thing.

What actually happened was many people didn’t want to batch order PCB’s (minimum order is 5) based on the instructions I gave, so contacted me for individual boards. I had so many excess boards from working out how to make the PCB’s in the first place, I decided to sell them.

I think tbh many of the hardcore Ciat people, who were originally interested in these circuits over the years now have what they need, so there isn’t such a big demand for them, like there was originally.

All I want to do at the moment is to put the missing Osmond files paper circuits on PCB so that’s the reason I started working on the Solar Sounders.

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#713

yes, I am. a layout would be really great.

this is exactly how i was construing a ‘half’-Rolzer! and likely how i would want such a module internally oriented, perhaps w gradated banana jack colors to indicate highest-lowest range capacitance.

same.

the current main obstacle for me is the construction of an enclosure, i.e. drilling holes in aluminum etc.

#714

Here’s a breadboard / stripboard layout for a 3-roll and a 4-roll.
It’s easy to create 5 & 6 rolls, but I’ll leave that as an exercise for the reader! :slight_smile:

The red out here is like on the CL Rolzer - it’s positive going, around 8v if you power this from a 9v battery with diode reverse polarity protection. These are the outputs to connect to the inputs of the Ultrasound filters, the AV Dog and the Gongues. It should be safe to connect to a Eurorack system but check your module specs first.
The black in / outs are the sandrodes, connect these to each other to get interesting rhythms. Don’t connect these to any other equipment, they are negative voltage and potentially high current.

The symbol in the middle is an LED.
Thanks to Peter Blasser, Meng QI, mlogger and Richard Brewster (Pugix).

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I’d recommend building this on breadboard before getting the soldering iron out! There may be mistakes.

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#715

Dogvoice testing with Eurorack envelopes / triggers…

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#716

Sorry for the silly question but what other components have you added in order to get the LED’s to work with the 220K resistor?

I’m aware of how Richard Brewster has his via the adapted CGS LED Driver, just wondered how you did yours? Thanks for any info.

#717

Here’s mine:

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#718

First post from myself…
I have been pondering the rollz circuits for a few days after speaking to Rodrigo.

Has anyone thought of making an anti-roll? This could be achieved by swapping out the npn transistors with pnp’s.

As time = capacitance x resistance has anyone put a resistor in the circuit anywhere?

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#719

That’s an interesting idea, would anything else need to be altered or adapted on these circuits or just change the transistor type?

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Yes, I’ve certainly noticed changes in activity rate if I clip resistors or capacitors etc across the Rolls nodes.

#720

A pnp works the oposite way from a pnp. So I would imagine not. Definitely worth a go. It would only take 15 mins you knock up a four node roll. I don’t have a working rollz otherwise i would go for it.

As for a resistor you could just put it in series on the supply to each Roll. Then you could fine tune the speed as required. Or possibly have two busses for the supply for each of the resistor types.

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#721

I have some spare Rolls boards, I’ll give this a whirl and report back… Interesting ideas.

#722

Oh and I have designed some dogvoice pcb’s in Eagle

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#723

That should be the 22K resistor, of course. Sorry for the typo!

I didn’t use an LED driver circuit of any kind, it was more of a trial and error method :wink:. I poked my multimeter around on the PCB, found the positive pulse behind the 22Ks and connected the LED on one of them via a 270R resistor. I used the same positive pulse for the orange outputs (and didn’t connect the regular output for that node). Since I am not an electrical engineer, it’s not unlikely that this is a very wrong way to do this, so don’t take my advice on this!

1 Like
#724

When I tried the method that @sbaio describes, I found that the pulse which the led was connected to was shortened. I think this was due to the capacitor being discharged through the led.
That’s why I added the LED driver, which is the same as shown in @corpusjonsey schematic.

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#725

You could use a hex inverter if you wanted an output that was buffered. Or is the whole idea to chain the positive nodes together too?

Music from outer space has good examples of hex invert buffers and LED drivers.

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#726

I’m not sure if this was directed at me, but for me the idea behind the positive outputs was to have something akin to the orange outputs on the rolls of the Plumbutter: a positive voltage that’s related to the negative pulses. I never tried chaining the positive outputs of the rolls.

Thanks for the hint at Music From Outer Space. Never heard of the site and I love it. What a great resource!

#727

Looking at the rolls circuits again, this makes a lot of sense. I think I need to upgrade my LEDs with a decent driver circuit.

#728

@sbaio yes I guess it was directed at you. Was thinking of implementing a similar positive output. The only problem is the pulse would be a binary output. Which isn’t a problem for gate/trigger signals.

Ray Wilson from Music From Outerspace was a lovely guy RIP. I use his website a fair bit for inspiration and education.

#729

I put together a 6-Roll board this morning using BC557C PNP’s instead of NPN’s and got no output on any of the nodes… Seems like something else maybe needs adapting, or I’ve made an error somewhere. I’ll do some proper checks with a multimeter when I get more time but as it stands… Nothing happening.

On a different Roll board I put a 50k pot and a 10k resistor in instead of a 22k and that does have some effect on the speed of the pulses. The speed change isn’t huge so I might mess around with different value combinations but certainly seems to work as you described.

#730

If you look in the Roolz-Gewei / Labrolz paper:

it shows the circuits for the rolls that are in the Plumbutter. These are tempo adjustable rolls, but are more complicated circuits. I’ve modelled them in LT Spice, with a voltage divider emulating the potentiometer, and they work in Spice. I haven’t built them, though!

There are two parts to the circuit: one that contains the pot, two resistors, two PNP transistors and one NPN. This produces / restricts the current going into the rolls.
Then each roll contains a PNP and NPN transistor, two resistors and one (electrolytic) capacitor.
So, they are more complex circuits than the simple rolls, but should be buildable.

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#731

Just a thought - if I’m using BC557C PNP’s with electrolytics as hairy caps would they need to be reversed in order to accommodate the different transistors?

(I’m largely ignorant of how this circuit actually works, in case that isn’t obvious by now) :slight_smile: