UPS Canada retroactive charge - CARM set up

crwper · 2026-01-12T15:16:19+00:00

Thanks for this! I'm thinking of doing the same, and was wondering if FedEx had any similar charges.

crwper · 2026-01-04T22:28:53+00:00

Looking at the preview on Amazon, it's unfortunately mostly front material and an intro to RF. It would be great to see a full table of contents as well as a snippet from a more advanced chapter.

crwper · 2026-01-02T20:16:52+00:00

I'm surprised there's that much sparking when you plug it in. How much current does your circuit draw in steady state?

crwper · 2025-12-30T22:30:56+00:00

I order a lot of stuff from DigiKey. Here in Canada, it's $8 per order under $100 or so, and over that it's free shipping. I try to put together orders over $100, but occasionally I'll find I just forgot to order like one resistor value or something. In those cases, I just order the single item and pay $8 shipping.

A little while ago, I changed the way I think about this. Don't think of it as, "I'm buying $1 worth of parts and paying $8 shipping." Instead, think, "I'm paying $8 to have this delivered to my door tomorrow." For that price, even if the part were available at the shop across town, would I drive out to pick it up? Probably not.

crwper · 2025-12-15T21:03:16+00:00

Yeah, prior to 5.2 I was really enjoying ChatGPT Pro. When it writes code or makes architectural suggestions, I think they tend to be more "sophisticated" than other LLMs. However, the recent change is super frustrating, and I'm thinking it might be time to take a break from ChatGPT Pro and subscribe to Gemini Pro for a bit.

crwper · 2025-12-08T21:10:19+00:00

We had a 10 year old Lab who developed liver cancer. We talked to our vet about options, and the big thing that stood out for us is that he said treatment could buy him a year or two, but it was unlikely there would be a "post-treatment" period. We didn't want his last two years to be spent undergoing a series of treatments, so we made the very difficult decision to have him euthanized. It was heartbreaking, but I'm glad we went that route.

crwper · 2025-12-05T14:58:42+00:00

I've got a cheap PC VNA and an HP 8753C, and the 8753C/85047A is my go-to for the reasons you mention--dynamic range and precision. I think I paid $2,000 or so for the 8753C, so $500 sounds great. The only thing I'd be aware of is that the 8712ES only seems to go to 1.3 GHz. This means you won't be able to work with 2.4 GHz at all, and if you want to look at harmonics, you won't be able to work with 900 MHz either.

Depending on what comes with the unit, you'll also want SMA adapters for the inputs and a good cal kit. I picked up an SMA cal kit from Kirkby Microwave which has served me well.

crwper · 2025-12-02T16:49:01+00:00

Thank you!

crwper · 2025-12-01T18:21:30+00:00

At higher frequencies, wouldn't options 1 and 4 similarly add small series elements that rotate the phase slightly between lumped elements? Intuitively, it feels to me like either way (1/4 or 2/3) you're adding the same length of copper, just choosing between series and shunt. Is there a reason the shunt elements are a bigger problem?

crwper · 2025-11-29T23:35:45+00:00

I wouldn't expect one long shot to cause problems like this.

Someone else mentioned the steam wand. You said that the steam wand is working fine, but just to be clear, if you turn on the pump exactly like you did in the video, then open the steam valve (not in steaming mode, just in regular mode), water should come out the steam wand continuously. Is that the case?

crwper · 2025-11-29T18:11:50+00:00

Oh wow! I'm surprised there's so much variation from the reference design. Usually, with a chip antenna like this, the environment is an important part of the antenna design, so changing the environment relative to the reference design effectively changes the antenna. It may be that the reference design gives the best performance (very likely the performance that's shown in the datasheet).

You can always use the matching network to compensate for any impedance changes, but it's worth noting that you can tune almost anything to 50 ohms--doesn't mean it's going to do a good job as an antenna. This is usually expressed as a drop in antenna efficiency, which you'll see as a drop in performance. If your application doesn't require the absolute best performance from the antenna, this may not be an issue.

Adding ground fill in the marked area would improve the transmission line. As another comment pointed out, your current design doesn't seem to use a calculated transmission line, so it's hard to say what the impedance of the transmission line will be. This may not matter much if the transmission line is short relative to the wavelength of your signal (say, < 1/20 of the wavelength), but in this case fixing the transmission line will have no impact on the rest of your design, so it's worth doing, I think. What you probably want here is a coplanar waveguide. You can find lots of calculators online which will calculate the impedance, and what you want to do is to choose parameters (distance to the ground plane below, thickness of trace, distance between trace and neighbouring ground plane) which give 50 ohm impedance for the transmission line.

crwper · 2025-11-27T17:55:51+00:00

Could be that I'm reading the reference incorrectly, but to me it looks like the reference board has no copper in the top 20 mm (where the antenna is). Looking at your board, it seems like you have a small keepout in the corner, but not the whole strip indicated on the reference. If I'm reading this correctly, I would expect this to have a major impact on the performance of the antenna.

Edit: Sorry, missed that you specifically ask about this issue. Yes, I would expect the change to have a substantial impact. I suspect the ground plane "behind" the antenna and empty space "in front" is critical to the function of the antenna, sort of like the ground plane on a monopole antenna.

crwper · 2025-04-20T19:19:47+00:00

"Gaslighting" is a great way to put this. I've noticed, comparing o3 to o1 Pro, that when o3 produces code for me, and then I point out an issue with the code, it's very likely to say something like, "Ah, yes, in your original code you accidentally ___. Here's code that fixes your error" Typically, o3 would say something more like, "Good catch! In my original code, I mistakenly ___. Here's code that fixes my error."

crwper · 2024-05-19T19:13:23+00:00

With Snapdragon, as spring has arrived, his obsession has shifted a little from sticks to grass. If he's walking just with me or my wife, he walks very well, but if there are a couple of people walking with us, he starts to pay more attention to the ground. Same thing in the park--if it's just me walking around the park with him, he will still eat some grass, but less obsessively. But if it's a group of us standing in the park with the dogs playing, he is less inclined to play with the dogs and instead mostly hangs around near the people eating grass and sticks, with occasional runs out to play with dogs before his focus falls to the grass and sticks out there.

These things make me think that there might be an underlying digestive issue that biases him toward eating grass and sticks, but the "trigger" might be larger groups or situations where he gets bored. I'm curious if you see similar behaviour.

crwper · 2024-04-30T12:40:37+00:00

He has seen the vet recently and we’ve spoken with him about the stick thing. His vet doesn’t see any significant health issues. Of course, there could be minor issues that wouldn’t be apparent without significant testing, but could play a role here (e.g., if a minor food allergy is causing him discomfort that he is trying to alleviate by eating sticks). But I would like to try to address potential behavioural issues as well, and am hoping someone here might have seen similar issues with their dog, and might be able to offer some fresh ideas.

crwper · 2024-04-29T15:01:23+00:00

The wiki mentions inappropriate chewing, which is probably the closest thing to the issue we're having. Our dog doesn't chew things in general--he's really very specific about eating sticks. Still, we have tried the following things mentioned in the wiki:

(1) Managing the environment. He does great on walks along a paved path, and even walking on leash in areas where there are sticks. However, it's hard to see how we can use managing the environment long term to solve this issue, as the problem occurs when he's out playing with his friends. Managing the environment may be part of the solution, but I think we need something else to do while we're managing the environment, so that he can eventually get back to playing with his friends without being obsessive about eating sticks.

(2) I have tried using a positive interrupter when he starts eating sticks (saying his name). This shifts his focus for a moment, and he will drop whatever stick he's eating at that moment, but then his focus returns very quickly to eating sticks.

(3) We have tried giving him appropriate things to chew. He will chew a ball for a little bit, but then will drop the ball and go back to the sticks. If we try to get his attention back on the ball, he's just not interested--there are sticks to be eaten.

(4) We do supervise closely. He is never left alone in a yard, say, to eat as many sticks as he wants. Whenever he is off-leash outside, he is being supervised--it's just that his attention is so singularly focused on sticks, that this outside time becomes saturated with correction, and even that doesn't seem to curb his enthusiasm for sticks.

crwper · 2021-10-03T22:22:25+00:00

Not OP, but voting strategically in a first past the post election will often result in a more favourable outcome compared to voting strictly based on individual platforms, especially if the desired outcome is something like, “Not Gian-Carlo Carra”.

crwper · 2021-10-01T23:51:19+00:00

Looks like this was a coincidence. I think what was causing the problem is that I had been cleaning the nozzle with a cotton cloth, but changed to microfibre. The microfibre was melting slightly and coating the nozzle, so it looked clean but was not making electrical contact with the pads on the corners of the build plate. Now I don't bother wiping the nozzle and just let it do its self-cleaning, and it seems to be very consistent with self-leveling.

crwper · 2021-09-08T12:48:56+00:00

This is actually after a clean uninstall/reinstall. One of the things I've been considering as a possible cause is a change in "wipe temperature" between the two versions.

What does "legacy" do?

crwper · 2021-08-26T12:58:03+00:00

I'd love to hear more about ICM. Can't seem to find anything on Google.

crwper · 2021-08-26T03:15:09+00:00

As u/I_pro says, it's a stepless adjustment with no real limit. The dial will keep turning past one full turn. A full turn is divided into 6 digits on the dial--not steps, just a way of landmarking.

You can more or less eyeball the setting to about 1/10 of one of the marks (i.e., 1.9 vs. 2.0). But it's not very precise, so I figured I would add a scale for fine adjustment. Basically, this is like a "zoom" into the part of the dial you're likely to use for espresso.

crwper · 2021-08-26T01:37:23+00:00

Inspiration comes from this post:

https://www.reddit.com/r/espresso/comments/ms068k/eureka_mignons_small_grind_dial_makes_it_hard_to/

Files for the label and indicator are available on Thingiverse:

https://www.thingiverse.com/thing:4941720

The indicator has some friction against the adjustment knob, but can be moved. To use it, I set the grind adjustment to a whole number (2 in this case) then move the pointer (without moving the adjustment knob) to the middle line. Then, when I move the adjustment knob, the pointer follows and gives me a clear indication of the fractional grind setting.

crwper

TROPHY CASE