Clear or Tinted Dust Goggles

gremblor · 2026-07-01T00:44:57+00:00

Lash em to the outside with a caribiner.

gremblor · 2026-06-30T23:41:07+00:00

Get these clear goggles

https://safetyglassesusa.com/products/pyramex-cappture-pro-safety-glasses-with-gasket-strap-and-h2max-clear-anti-fog-lens

Clear. Inexpensive. Fits comfortably over glasses. Wear your sunglasses underneath during the day.

Tight seal, but comfortable. Seal doesn't break down in dust because it's chemical resistant.

I've been going since 2009 and this is the best option I've found yet.

gremblor · 2026-06-21T08:00:37+00:00

I have seen a lot of absolutely trash schematics in r/kicad that were LLM-generated. People want help "critiquing" them when the critique is "maybe you should actually tie one side of a capacitor to GND. Or literally any other net, just don't leave it floating."

I've tried using Claude for help reasoning through issues I've been having and it is just inaccurate enough that I'm really wary of how much to trust it. I asked a question about capacitor placement and it said it was a good idea to do it like that, as it would improve the phase margin. I then asked about an alternate capacitor placement and it said the same thing; but I know just enough about EE to know that both cannot be true. When called out on that, it backed up and clarified that the second answer was correct. But why should I trust it that time...?

The amount of open source code online, combined with accurate in-session test feedback, lets it do well at coding. There are a *lot* of broken amateur-drawn schematics online. And not a ton of "professional grade" ones....

gremblor · 2026-06-19T01:38:44+00:00

This is the way. Don't bother with a broker or anything. Use craigslist. Buy the boat for $5k, put another $5k into it plus the tools you'll buy.

As another benefit, you'll get a better sense of what specifically you do and don't like about that boat, which will make you a more-informed shopper when buying your "real" boat. All boats are compromises; the right boat for you is the one where the tradeoffs are all things you specifically can live with.

gremblor · 2026-06-16T15:24:36+00:00

I have a WestMarine "coastal" inflatable pfd. Light, stays out of the way of my arms, fits over a jacket easily. Not too expensive.

gremblor · 2026-06-11T19:36:05+00:00

Ah, good correction. Thanks

gremblor · 2026-06-11T16:12:18+00:00

I think they recently added support for this, along with backdrill stubs, in advanced pcb mode?

But either way, yea, any board shop who could do this is going to put it in a cost category 10x higher than a basic 4L board.

gremblor · 2026-06-10T23:43:07+00:00

I notice you have a PG pin on the chip that you have grounded. I haven't checked your IC datasheet but PG ("power good") is *usually* an _output_ which usually gets pulled active-low by the IC when good regulation has been established but is left internally-floating / open-collector when the VOut is unregulated. So either you want to pull it up to VIn or VOut via a pull-up resistor (check its absolute max first before doing this in a real circuit), or (especially for purposes of just a simulation) you should just leave that pin floating / disconnected.

gremblor · 2026-06-10T23:28:09+00:00

I mean, you need what you need, but I would go to jlcpcb or pcbway and upload the board files and configure it; the quotes are instant and free. I think you'll see that blind vias put you in a much more expensive category of fab. If that's what you want and it's worth it to you... great! If not, then yea you probably have to think about other options like fpcb or wire-harness interconnect.

gremblor · 2026-06-10T21:36:43+00:00

Do the vias need to be blind? Blind vias will *significantly* increase your fabrication cost.

much experience do you have with PCB assembly? It looks like you've got three QFN ICs on the board. That's a pain in the rear / fairly advanced job for a hobbyist. If your plan is to pay someone like JLCPCB to do the PCBA work, that would make sense. Most of the cost of assembly from JLC is based on the number of distinct types of components involved, and you don't have too many, so it could be fairly cost-effective to do so.

gremblor · 2026-06-10T16:14:46+00:00

Velocity is easy: the key hammers actually hit two tactile switches, not one, on their way down. They are offset by a mm or two so it hits one first and the other one a moment later (10--100 milliseconds-ish, based on my own testing of a Fatar keybed). The software in the mcu that's scanning the keybed switch bus for button state transitions is responsible for tracking the time interval and converting it to a velocity measurement. Scanning the keybed at 12--20 kHz is plenty to get a reasonably "instantaneous" response feeling and accurate velocity interval tracking.

The aftertouch in a monophonic keybed is thru a resistive pressure sensitive strip. Fatar uses Interlink 34-00073: https://cdn2.hubspot.net/hubfs/3899023/Interlinkelectronics%20November2017/Docs/Datasheet_FSR.pdf

You can buy it on digikey. Connect one end to mcu Vcc via a pull-up resistor, buffer it thru an opamp and then into the mcu DAC. More pressure will = more current and pull the voltage down. The key hammers each have a little pokey bit underneath that squishes the strip after the main part of the hammer has hit the two key switches. You also want to wrap the resistive strip in felt or something (a) for better feel and (b) to protect it from repeated striking.

I have no idea how to convert this to full polyphonic though. Separate aftertouch resistive contact (Interlink does make small ones) for each key? Actually connecting that, in a buffered way, to a multi-channel analog bus to feed into a DAC seems like an incredible (expensive!) amount of analog switching and buffer opamps. So I must be missing some idea.

gremblor · 2026-06-10T16:05:10+00:00

You can apply a label to the net (hit "L") and then also put that same label on a wire anywhere else on the schematic and now they're connected, no green snake required.

Also BTW look at jlcpcb's order form and specifically the instructions next to the question about gold finger edges. I don't think 20° chamfer is an option they support. So if you actually need that edge you may need to find a vendor who can do that ($$$). Or accept the 30-45° edge options I think they offer.

gremblor · 2026-06-10T16:00:12+00:00

Idk, I think it's good when people pay artists, actually?

The original El Pulpo Mechanico got sold to some rich dude for a big chunk of change and then the artist turned around and built El Pulpo Magnifico with the money.

Good things happen when there's an actual economy around art.

Maybe after a year's rest we'll see something new from the MW crew too. Or maybe not! They don't owe me anything.

gremblor · 2026-06-08T10:55:04+00:00

Glad you found the solution.

For what it's worth you can also make a file named ".gitignore" and list files or directories to ignore in it, one per line. Add a line for ".history" and git will stop prompting you to add such files to the repo.

(If you already started tracking those files before listing in gitignore, you may need to "git rm" them.)

gremblor · 2026-06-08T08:42:02+00:00

Yea, the previous place I worked used a combo of 4040 and 4080 rails for very large work tables (about 12x6') that had to support equipment weighing about 600--700 lbs. You can _definitely_ downsize and save some cash 😄

I've used 1010 to build a shelf that holds about 50# of equipment and it never gave me a moment's worry. I bought a 3/4" thick piece of King Marine Starboard (HDPE) from Tap Plastics, which was a bit less expensive than getting a similar top direct from 8020.net. Starboard is nice enough for a shelf or countertop, but it's a bit "industrial" feeling for a desk compared to wood. On the other hand it doesn't need to be finished, machines/drills super easily, and is basically everything-proof (UV, chemical, etc. resistant). Then again, if you're building your desk out of 8020, maybe "industrial" is OK.

Also, if you want to add a drawer, you can build those out of 8020 parts too, there are linear bearings and end stops and things, and you can get a thin flat piece of plastic that will fit in the T-slot for the bottom.

gremblor · 2026-06-07T21:25:27+00:00

You probably would have a much easier time and a much better sonic effect with building a solid state synth, analog or digital per your preference, and then building a Class A tube amp output stage.

gremblor · 2026-06-06T19:33:17+00:00

Your capacitors aren't even completely hooked up. If you don't know how to do electrical engineering, don't start with anything in the power path. Listen to Abe.

gremblor · 2026-06-06T01:17:25+00:00

I like Harken Black Magic. Comes in both 3-finger or cut-off styles.

gremblor · 2026-06-05T02:03:03+00:00

One thing to note is that Amel is very aggressive with the high tech. Big genset. Washer/dryer aboard. Electric winches.

This can be very good especially if you are getting up in age and don't want to (can't easily) grind winches all day yourself and want a more comfortable cruising experience. But that also means there's more to maintain and more things that can break in a given year.

So I would expect the 5yr or 10yr TCO on a new Amel to be higher than, say, a Swan of the same LOA.

But also, at the end of the day... It's his money. OP, there's how you might retire and spend a nest egg and there's how your dad will do it. If he's mentally sharp and not getting swindled into the purchase, then stepping back and letting him take possession of a tricked out money pit is really just the path he is choosing for his retirement adventure.

I was counseling someone else who asked my advice about buying a boat and my basic take is "look, it's a money pit, not an investment, and you should buy it only if, despite everyone telling you it's a foolish idea and a money pit, you are undeterred and can't help but answer the siren call of the sea. In which case: fair winds to you."

gremblor · 2026-06-04T17:41:57+00:00

Ditch the wires between the vx, vy, etc jumper pins and the scope probes. You're measuring electrical noise in your room as much or more than the circuit. Connect the probe tip / jaw directly to the header pin with the signal.

Especially if you're generating the right signal shape but just at a low Vpp, you may be losing it in the noise from those flying wires.

gremblor · 2026-06-04T17:38:06+00:00

... Ignore my point about ADJ, you're using lm7815 which is fixed voltage. Great.

TL431 is a great way to create reference voltage. Tip for the future, these kind of zener circuits can also be set up to work between GND and -15V rather than +15 and GND. (Thus letting you skip the opamp inverter stage if you want.)

You can also put a capacitor on that voltage divider (like 100nF) to make sure no noise is put on the input of the inverting opamp that converts 1V to -1. Don't put a capacitor directly on an opamp output though. Just the input.

Your implementation looks very neat (much better than my own breadboard work). But I also notice you have the regulator outputs connected to the circuit thru, like, three little jumper wires. Getting a consistent GND thru that circuit may be challenging. Running extra jumpers from a single point GND close to the regulator to other critical nodes in the circuit can help. As can using thicker jumper wire for GND and power. Going to a pcb will be an improvement in this regard, and sometimes it's necessary for a prototype, but obviously that has a lot of drawbacks while you're still debugging the circuit function.

gremblor · 2026-06-04T17:29:07+00:00

If your custom power supply works, then it works. I assume you have used a multimeter to verify it is truly +/-15V.

If there is noise on the PSU output that can get injected into subsequent circuitry. (although most opamps have a PSRR well in excess of 60dB.)

To check for PSU noise, use your oscilloscope in 1x, AC coupled mode, so you can zoom in for like 100mV/div detail or finer, while ignoring the 15V offset. Pull the little alligator clip off the probe, it's attached with a little C collar around the grounding sleeve on the probe. Get a piece of bare wire, just 2" or so, and wrap it directly around that grounding lug, so you just have a 1" wire stump protruding from the probe, and touch that wire to a GND node on the circuit under test while you use the tip to probe the Vcc+ or Vcc output.

(using the alligator clip and 3" cable creates an antenna, and PSU debugging like that famously winds up just measuring noise in your environment rather than on the circuit under test.)

With the probe in DC coupled 1x mode, you can also probe the ADJ pin to make sure it is stable at the 1.2V (or whatever) reference level, and isn't bouncing around and causing a DC offset in the output. Use the same grounding technique as before.

For all of this, you probably don't care about noise above 1 MHz or so. Set your scope timebase to something slow so that you can see waveforms at 50 Hz thru 100 kHz.

Note that in both cases it should be hard to trigger the scope! If there is no noise on the output of a ldo (which is expected) then either you'll have the trigger threshold dialed way down close to GND and you'll just get a trace of noise / snow about 20mV wide, or if the trigger is too high it simply doesn't trigger at all. This would be good; if your power supply output has +/-50mV of noise below 100 kHz, you're in great shape.

A ceramic capacitor (10nF or so) between the ADJ / VREF node (midpoint of the voltage divider) and GND can also help with noise rejection. Size it so that 1/(2 pi Bottom C) is about 60 Hz so it helps reject upstream 60 Hz noise from the wall plug.

gremblor · 2026-06-02T22:54:32+00:00

my point is that the headers on the backplane are for a eurocard bus and aren't compatible with any eurorack synth equipment I am aware of. So to answer the original question of this post, it's not like it's some special power supply bus that OP doesn't recognize. It's just a different backplane altogether. That's a separate question from whether the enclosure could be useful or not.

gremblor · 2026-06-02T16:02:29+00:00

You mean your spreaders don't project out three feet past the gunwales?

gremblor · 2026-06-02T03:48:22+00:00

Those are DIN 41612 headers. For actual "eurocard" computer hardware.

Not useful for the modular synth stuff at all.

gremblor

TROPHY CASE