No more Vactrols in the U.K.?

[ElectricDruid]

For audio, even if we found another material we would also like to keep the same kind of time constants.

That's mostly just us being lazy and not being bothered to design a proper envelope follower! Instead we want one part to do all the work for us and provide both *attack* and *decay* filtering with different time constants! Obviously, it's nice if such a thing exists and happens to provide just the numbers we need, but it's hardly the only way.

I'm being facetious, but you get the idea. A bit more work can easily work around limitations like, say, really-fast-reacting photocells.

[CheapPedalCollector]

Sorry to make it political Mark, but the reason this stuff happens is because of it, there's really no way around it. Ignoring the problem doesn't make it go away. However adult discussion about and trying to get people to understand factual information (the point of this board in many respects) is paramount to solving the *actual* problem. I've grown tired of the being punished because one kid brought bubble gum to class, and all the idiots dog pile on it because they are too ignorant to do otherwise and are trained to act this way.

Are there alternatives that work the same? Maybe? The stuff that claims it is cadmium free doesn't have much information on construction as datasheets these days hardly qualify as such most of the time, if you can even find one. I suppose a patent search is in order for that. Does anyone know what they are using? I'm not very good at patent searches.

I suppose I better start stockpiling some for repairs before I can no longer get them, but then obsolete parts has always been a problem.

[Rob Strand]

That's mostly just us being lazy and not being bothered to design a proper envelope follower! Instead we want one part to do all the work for us and provide both *attack* and *decay* filtering with different time constants! Obviously, it's nice if such a thing exists and happens to provide just the numbers we need, but it's hardly the only way.

I'm being facetious, but you get the idea. A bit more work can easily work around limitations like, say, really-fast-reacting photocells.

No worries, I'm on the same wavelength.   At least with fast cells you can massage the performance with external circuits to a reasonable extent.

The thing about Vactrols is the time constants aren't quite constant.   It's not simple to emulate exactly over a wide range.   It's something I've had on the to-do list for a while - but as time goes on I'm less motivated to spend time on it.

the reason this stuff happens is because of it, there's really no way around it.

Also the whole reason RoHS is a problem is because it is a law issue - laws are dictated by governments.   That's why (most) medium to large companies take this stuff seriously.  If you don't comply your whole income stream can be cut-off.   The backyard operations try to get under the radar but if you get caught there are consequences - people make drugs in their backyard and we know what happens when they get caught.

I suppose I better start stockpiling some for repairs before I can no longer get them, but then obsolete parts has always been a problem.

I believe parts for repairs don't fall under RoHS because you aren't selling products - not 100% sure how the rules are rolled out though.   You may have local issues disposing of old parts though.   The problem with banned technologies is there's a point where no one will make the parts, then you can't *buy* the parts for repairs.   There was a time where aircraft repairs would fix old CRT devices but as time went  on there were schemes to retrofit LED technologies - since this is like modifying the aircraft you can't just start using new parts.  At some point germanium transistors and vacuum tubes will suffer a similar fate.

[bartimaeus]

Silicon
ie;
Photodiodes CADMIUM-FREE LIGHT SENSOR
Type   High Sensitive Light Sensor
Photodiode Material   Silicon
Peak Wavelength   580 nm
Maximum Dark Current   0.3 uA
Fall Time   8.5 ms
Light Current   260 uA
Maximum Operating Temperature   + 85 C
Minimum Operating Temperature   - 30 C
Mounting Style   Through Hole
Packaging   Reel
Power Dissipation   40 mW
Product   Light Sensor
Reverse Voltage   6 V
Rise Time   8.5 ms

very interesting! where did you find this?

every photoresistor i can find on digikey is CdS type (in fact the category is just called "Photo Detectors - CdS Cells").

Xvive claim that their RoHS vactrols are free of both Lead and Cadmium, and are therefore legal to sell. They provide a legal RoHS declaration to this effect, which is (sometimes) necessary to show customs in order to be able to import the devices into the EU. Prior to Brexit, that would have been the same rules in the UK. Now, they'll do the same thing, but it'll be much better because Brexit improved everything, right?

interesting! do you know what they use instead of Cadmium? i'm surprised that nobody else makes Cadmium-free photocells if it's possible... i know the datasheet says "Cd-free", but i have to wonder if they're ROHS by (expired) exception rather than using a different material.

No, I don't know, sorry. The RoHS declaration is pretty clear that they're Lead and Cadium *free*, not just covered under some exemption. Here's an example test report:


https://electricdruid.net/wp-content/uploads/2023/02/Opto-coupler-RoHs-testing-report-by-SGS.pdf

My understanding was that there are quite few non-cadmium photocells out in the world, along with phototransistors, photoFETs, and many other types of non-cadmium photosensitive devices. So I don't think we're out of options any time soon! It's just that we're often trying to reproduce circuits from 30/40/50 years ago, when cadmium photocells were the go-to option.

thank you for clearing that up! i'd been thinking phototransistors and FETs were the main alternative, but obviously those have some drawbacks that need to be adjusted for.

https://northcoastsynthesis.com/news/voltage-control-modifications/

i'd been reading this article, which is pretty pessimistic about the alternatives the CdS photoresistors. i guess they aren't up to date on what's available :O

[Phend]

Reference only, not sure if this is of any use, but..
X out the box at the bottom and open the pdf

https://www.datasheet.directory/pdfviewer?url=https%3A%2F%2Fdatasheet.iiic.cc%2Fdatasheets-0%2Fpanasonic%2FAMS302T.pdf

[Rob Strand]

Reference only, not sure if this is of any use, but..
X out the box at the bottom and open the pdf

They are the type of sensors I mentioned earlier.  They are used for light measurement.   
They output current.

[bartimaeus]

thank you phend! unfortunately i'm not interested in measuring light, i want variable resistance haha!

it's a shame that xvive don't offer the photocell from their vactrols in isolation.

[Phend]

O well , just built a colorsound using a clm6000 from smallbear. Probably not ralavent either since this thread is about the banning of cadsulfide.

[merlinb]

CdS photocells can still be used in Europe when:
1: The mass of cadmium relative to the mass of *the entire product* falls below some threshold (don't ask me exactly what the threshold is, but one photocell in a pedal probably complies) and;
2: You can demonstrate that your product will have a long lifespan and isn't the sort of disposable appliance that will regularly end up in landfill.

[Ben N]

Fun Cadmium Fact #1: Smoking is the biggest contributor to chronic Cd poisoning for smokers.

And don't forget chocolate! https://www.consumerreports.org/health/food-safety/lead-and-cadmium-in-dark-chocolate-a8480295550/

Can this be the "cad" in Cadbury?

[Rob Strand]

CdS photocells can still be used in Europe when:
1: The mass of cadmium relative to the mass of *the entire product* falls below some threshold (don't ask me exactly what the threshold is, but one photocell in a pedal probably complies) and;

That's a really good point.  I'm so used to total eradication in parts these days.

https://www.rohsguide.com/
Cadmium (Cd): < 100 ppm

The phrasing impacts components and spare parts:
"Any business that sells applicable electrical or electronic products, equipment, sub-assemblies, cables, components, or spare parts directly to RoHS-directed countries, or sells to resellers, distributors or integrators that in turn sell products to these countries, is impacted if they utilize any of the restricted 10 substances."

[bluebunny]

https://www.rohsguide.com/
Cadmium (Cd): < 100 ppm

So if I have one million pedals, only 100 of them can have Vactrols?  I'd better get building...   

[Phend]

Sounds to me that this effect building hobby might be hazardous to our healths.
You got the :
CdS, Pb, Flux fumes, Paint fumes. Darn thing doesn't work anxiety.
What else?

[Ben N]

Sounds to me that this effect building hobby might be hazardous to our healths.
You got the :
CdS, Pb, Flux fumes, Paint fumes. Darn thing doesn't work anxiety.
What else?

I keep telling y'all: stop chewing on the damn vactrols!

[Phend]

What else,
ADDICTION

[PRR]

What else?

Solder licking.

[GibsonGM]

Burns.  Inhalation hazards from solvents like pot cleaner, acetone...puncture wounds from stepping on tiny needle-nose pliers in socks (don't ask me how I know this).

[Axldeziak]

Cadmium (Cd): < 100 ppm

so just screw the vactrol to a big-ass slug of scrap metal. It's not your doing if the end user unscrews it and uses it elsewhere.
Stupid laws deserve stupid solutions...

[CheapPedalCollector]

Yeah I wonder who chews on their guitar strings.

[stallik]

^ Hendrix did that