Skyking, Skyking, Do Not Answer

After some aimless browsing, I somehow came to be reading about the Jim Creek VLF facility in Washington State, used for communications with (or, more accurately, communications to) submarines. Even with miles and miles of wire antennas in the air, and even with more than a Megawatt out, the signal isn’t able to penetrate very far in saltwater.

This reminds me of the Skyking broadcasts carrying instructions to nuclear-equipped Air Force resources. There are both Emergency Action Messages and Skyking broadcasts, with the latter apparently having higher priority. They’re read live over the air and are, of course, encrypted messages.

They’re arguably similar to the various numbers stations, which broadcast information encoded with a one-time pad and are used to communicate information to people in the field. For example, see The Lincolnshire Poacher, which begins with the titular melody being played repeated, presumed to be an attention signal to aid in tuning. Many of the numbers stations use a recorded voice reading off numbers or letters. Some of what we know was confirmed when the US tried five Cuban spies.

Murray G2250030 Snowblower Parts

A neighbor gave me an old snowblower she didn’t need, a green 22″ Murray 5HP model. A label on the back identifies it as model number G2250030. I’ve been trying to fix it up and get it running on the side, but it’s been a bit of a challenge. I cannot for the life of me find a manual. at least has some parts diagrams. From there and some Amazon exploration, I’ve found some replacement parts. Note that I’ve just now ordered these; I’ll come back and update this to reflect whether the parts are correct or not.

Shear Pins

As best as I can tell, these are identified as part 9524, “Screw, 1/4-20×1.75” and part 3943, “spacer, sleeve” in the auger housing assembly parts diagram.

I think these are what you want.

This eBay listing suggests that parts 1501216 (and 1501216MA), 9524MA, and 3943MA are equivalent, and that Craftsman used the 9524 part number as well.

Whatever you buy, make sure you get the spacer. Some reviews on other parts (not linked here) indicate that people cannot find the spacer individually.


I plan to replace both drive belts while I have the thing apart.

The drive belt (turns the wheels) is part 579932, described as “Belt V 3L 33.13LG”. I have this in my Amazon cart right now. (Note that the “MA” prefix is often added to Murray part numbers, so it’s also known as 579932MA.)

The auger drive belt is 581264, described as “Belt, V 4L 35.23LG”. I have this on order.

Auger throttle cable

The cable to engage the augers is the faulty part I’m actually trying to replace. It’s part 340373, “Cable, auger.” It appears that this part number has been replaced by 761400MA, which is also apparently equivalent to 760150, 761153. See this part, which is running about $38.

Low-Overhead Linux Networking

I want to do more posts here that are quick roundups of interesting things I’ve read, rather than rambling commentary.

  • DPDK, the Data Plane Development Kit, permits a userspace application in Linux or BSD to bypass the kernel and directly interact with a network card. Handling interrupts to pass data from a 100 Gbps network card through the kernel apparently performs poorly.
  • Selectel’s “Introduction to DPDK: Architecture and Principles” looks like a detailed walkthrough of how it works. (I only skimmed it on the train tonight though.)
  • is a Linux Foundation project implementing a software dataplane employing vector packet processing (VPP). Its What is VPP? page is a good intro.
  • networking-vpp brings support to OpenStack networking.
  • Ligato and Contiv-VPP bring VPP to Kubernetes (et al.)
  • I’ve run up against mentions of YANG, which is “Yet Another Next Generation” DSL for modeling network data.
  • Intro to networking-vector packet processing is based on a 2018 FOSDEM talk. The Youtube video really helped things “click” for me.

2018 Camaro SS review

Last week, I had to have my car towed into the shop—and then from there to the dealership. (It felt sort of like when someone is taken by ambulance to a local hospital and then taken by medical helicopter to a larger hospital.) The dealership didn’t have any loaners, so they called Enterprise.

Now, Enterprise isn’t a bad company, and their cars aren’t necessarily undesirable, but no one bringing their car to a BMW dealership is hoping for an Enterprise rental. Like any other rental company, the car is always a little tin can that somehow doesn’t have GPS in 2018.

So imagine my surprise when they gave me the keys to this:

I didn’t know much about Camaros, but it turns out that, even more improbably for a rental car, this was one of the good ones, the Camaro 1SS with a V8 making 455 horsepower. Sitting in the driver’s seat with the Enterprise employee in the passenger’s seat as we completed paperwork, it was hard to contain my grin as I pushed the start button and the car let loose a throaty growl.

Once I filled out all the paperwork promising to treat the car gently and the Enterprise employee took off, I tried to at least leave the lot before doing all the things I said I wouldn’t. In my car, you need to give the pedal a fair bit of pressure when the light turns green. I almost think of it as slack in the pedal. Of course you don’t slam the pedal to the floor, but if you’re too ginger, people are going to start honking. Getting a heavy car rolling takes a bit of gas.

At first blush, the Camaro seemed the same. Give it a tiny little bit of gas, and the engine doesn’t deliver much power. So you do what I do in my car—give it a fair bit of pressure. And—oh shit!—that’s how I peeled out of the lot. With way more power than I expected, I let off on the gas in a panic, leaving me rolling through the intersection slowly and looking even more like I shouldn’t be trusted with this car. It didn’t take long to find a better balance, but it certainly wasn’t a great start.

Driving is a blast, though. It’s loud, and packs an awful lot of power. Whether it’s driving around town or passing a slowpoke on the highway, it doesn’t take much to get this thing going, and it’s hard to not have fun while doing it.

An interesting thing I discovered is that the car seems to shut down half of the cylinders when you’re cruising along at a steady speed, which is probably why the thing gets more than 20mpg:

(I don’t know who took this photo, but I’m sure they were on a dyno.)

But go to pass someone, and those extra cylinders come back in the blink of an eye. You’d never know they weren’t running if not for that screen showing it.

The specs show a 0-60 time of about 4 seconds. I didn’t dare try to run a timer while pinned to the back of my seat on the onramp, but I don’t doubt that number. I never got to the end of an onramp wanting for speed, but did often have to let off the gas long before the end because I had surpassed 80.

The ride wasn’t _un_comfortable, but you definitely felt every little bump in the road… And New England roads aren’t exactly smooth in early spring.


I had no trouble with headroom, but the car does sit quite low which probably helps. Audio controls on the steering wheel help you keep your eyes on the road, though I missed the volume controls my car had. The steering wheel felt like leather, imitation or not. The bottom of the steering wheel is squared off for reasons I don’t entirely follow; perhaps to help with legroom getting in. It was a little odd turning into sharp spaces where the steering wheel wasn’t round, but I tend towards shuffle steering so it didn’t come up too often.

A decently-sized LCD in the center console shows everything, from music to climate control settings. Climate control has dedicated hardware buttons, and adjusting temperature or fan speed is done by turning those huge center vents. An overlay on the LCD simply shows where they’re set. The screen has a slight downtilt which seems to prevent the glare that plagues my car’s center screen.

In the instrument panel, the tachometer and speedometer are both large analog meters. Their layout is the opposite of a BMW, but it’s not like it’s hard to figure out which is which. The gauges in the middle are digital displays styled to look like analog meters. A compass readout is front and center, and was just a tad distracting while turning.

The rearview mirror was adequate but remarkably small. At the same time, that also describes the rear window, so perhaps they’re paired well. Flipping the mirror to night mode is done by hand (soooo 2015!), and the button is recessed directly behind the OnStar button. Pressing the OnStar button by mistake makes a loud chime that will freak you out. (Ask me how I know.)

Visibility overall is poor. The front windshield is remarkably short, but gives an adequate view of the road ahead. Side visibility past 90 degrees, though, is atrocious. Trying to take a sharp left while watching for traffic from the right required crazy contortions with my head against the windshield to see past the passenger’s seat. You need to have your mirrors adjusted correctly in this, because peripheral vision is poor.

One review called the rear seats “vestigial,” which is the perfect word to describe them. I used them as a shelf to hold my umbrella. “Legroom” in the rear is comical; reaching to get my umbrella when it slid onto the floor, I didn’t have enough arm room to pick it up. Perhaps if the driver and front passenger have very short arms and legs and pull their seats way forward, you could seat four if the rear passengers were emaciated. I really can’t imagine when you could fit anyone in the back, unless they were maybe in a car seat. (And if you’ve got a toddler, I humbly submit that perhaps a Camaro isn’t the right car for you at this stage of your life.)

In short: having the Camaro for a weekend was a blast. And I certainly wouldn’t mind having one as an occasional fun thing to drive. But by the time my car had two functioning axles again on Monday, I was happy to get something more practical back. Visibility and comfort are surprisingly important.

Towerspotting: Mt. Uncanoonuc

In what is apparently now a series, here’s another “Towerspotting” post. This time I traveled to Mt. Uncanoonuc in Goffstown, NH. (Months ago, actually.)

]2Mt. Uncanoonuc from drone

There are actually two Uncanoonucs, South Uncanoonuc and North Uncanoonuc. South Uncanoonuc, actually the shorter of the two (by 3 feet), stands at 1,321 feet. It is suggested that the word “uncanoonuc” may be from the the Massachusett word for “breast.”

Just a short bit outside of Manchester, the 1,321-foot summit has a height above average terrain (HAAT) of about 250 meters, or 820 feet, which perhaps explains why it’s home to much of the southern NH TV and radio stations.

The contents of the mountain are perhaps better revealed by a lower shot from when I took my drone up there earlier this fall:

]4Mt. Uncanoonuc towers

From left, we’re seeing:

  • WGIR-FM’s old tower, now used for backup
  • A tall Crown-Castle tower (red and white), home to WGIR-FM’s primary antenna system (out of frame; some cellular stuff is all you can see in this shot)
  • Immediately behind it and barely visible, a self-supporter that I think is owned by SBA; home to cellular, microwave, some some land-mobile stuff
  • WMUR-TV’s antenna and tower, also red and white.
  • An abandoned (?) tower, comparatively quite short
  • WMUR-TV’s old antenna/tower from the analog-to-DTV cutover; a microwave dish is mounted much lower
  • WZID-FM’s tower; the 3 lumps on the side are their FM bays, with the two smaller red ones on the side being their backup antenna (I think).
  • Just to the right of it, almost overlapping, is a commercial land-mobile tower
  • Dead center, another commercial land-mobile tower. This looks to be one of the taller sites, over 200 feet, but I’m not sure it actually has an ASR on file ???
  • To the right, the diminutive-looking WNEU-TV tower that’s actually cranking out 80 kW, the most powerful station up there by far.
  • A wide self-supporter that I believe is owned by the Town of Goffstown. There may be another land-mobile tower directly behind it; not sure
  • A very short tower with a few VHF fiberglass whips. The site is on a very small concrete pad and houses a doghouse-sized enclosure that is literally falling apart. Town records have it appraised at six figures.
  • At far-right, an Industrial Communications tower, which looks to be home to cellular and land-mobile stuff.

I’m about 95% sure on those. Corrections welcome!

Here’s another view, showing a few of the towers and looking over to North Uncanoonuc:

]6 North Uncanoonuc, viewed from South Uncanoonuc

Here is WZID’s tower:

(It’s far more likely that my camera was a little crooked than the tower having a lean…) The structures at the very top are simply lightning rods/dissipators. I’m not totally clear what’s up there, but I suspect that the 3 bays at top are their primary antenna system, with the two smaller ones on the left being a backup. The antennas are cross-polarized, to serve listeners whether their antennas are horizontal or vertical, and consequentially look a bit strange compared to your average antenna.

The round dishes are most likely 900 MHz studio-transmitter link antennas, feeding the broadcast audio.

WZID is licensed for 14.5 kW on 95.7, though FMpower suggests that this is probably maximum power for a Class B station based on HAAT.

And here’s WNEU-TV, a Univision station:

Walking around the top of the hill, each tower is surrounded by a barbed-wire or razor-wire fence, and also contains a transmitter building. WNEU’s is one of the only ones that makes a lot of noise, with a substantial HVAC system with giant fans. It made sense when I started looking up licenses, and found that they’re licensed for 80 kW output.

For comparison, here’s WMUR-TV:

They’re licensed for 6.5 kW.

And finally, WGIR-FM, whose antenna we were almost looking into on some of the drone shots:

They are licensed for 11.5 kW at 101.1 MHz, but, like WZID, it seems this is maximum legal power based on their height.

There is also some ham stuff up there, including a few DMR repeaters through DMR-MARC, and a 220 MHz link for the N1IMO repeater. At one time there was a 6-meter repeater as well, but it seems to have faded from the Internet and I’m not sure it’s still around.

Understanding pepper (OC) spray ratings

Pepper spray has been legal in Massachusetts without any sort of permit required for a few years now. It’s also known as OC spray, from the extracted oleoresin capsicum, being an oleoresin formed from capsicum, the ingredient that makes hot peppers spicy.

I recently picked some up, and would like to share a few things I’ve learned.

Where to buy pepper spray

Finding pepper spray in MA can be hard. I’ve seen it in lots of places across the border in New Hampshire, but it’s hard to find in Massachusetts. Making it worse, shipping it to Massachusetts is either prohibited, or thought by online merchants like Amazon to be prohibited. I ended up picking mine up in a sporting/gun shop.

Why all the numbers are meaningless

But here’s the part that really trips me up: the ratings. The spray I purchased is listed as “10% OC (2 million SHU).” Intuitively, I assumed this meant that it was 10% of the maximum strength possible. (If 10% is 2 million SHU, the maximum must be 20 million SHU.) But this is totally wrong! The SHU rating or the percentage alone are meaningless numbers.

What this actually means is this:

  • The solution in the canister is 10% oleoresin capsicum, and 90% other stuff (inert ingredients). If this number were 100%, I assume it would be a sticky goop that you couldn’t spray, so it’s necessary that a decent percentage of the contents be something like water or propylene glycol.
  • The OC that’s in the spray is rated at 2 million Scoville heat units (SHU).

As an analogy: you have a rum and Coke, which is about 25% rum and 75% Coke. The rum used is 80-proof, or 40% alcohol. If your goal is to get drunk, neither of those metrics is meaningful on its own. 25% rum doesn’t necessarily tell you how strong the alcohol is, and “The rum in this Coke is 100 proof!” isn’t good news if they only put a dollop of it in your drink. What you’d actually want to know is the total amount of alcohol.

The same is true of OC spray. Sabre, one manufacturer of pepper spray, has a blog post explaining that you need to consider the product of the two numbers, known as the percentage of Major Capsaicinoids, or MC. The same math is discussed in a number of places; the Sabre blog post is just the first place I saw the math given a name.

Pure capsaicin is 16 million Scoville heat units. So if the oleoresin capsicum in my canister of pepper spray is 2 million SHU, it’s 2/16 = 12.5% of the maximum strength.

But only 10% of the canister is OC, so it’s 12.5% × 10% = 1.25% MC. (Well, the Sabre article uses the same starting numbers to arrive at 1.33%. I’ll assume that I’m the one that’s off on the math.)

A competing product is marketed as 6% and 3 million SHU. That’s 18.7% × 6% = 1.122% MC. Other sources have higher SHU ratings at lower percentages. This all gets very confusing, because manufacturers seem to just decide whether they want to market their product on having a high-percentage of OC, or on a high SHU number. You need to compare the total percentage of capsicum if you want to do any sort of meaningful comparison.


If you’re going to carry pepper spray, you would probably do well to also carry something like these decontamination wipes to help alleviate the effects, in case you end up getting some of the spray as well. (There are a few other products linked from there as well. Having never used any of them, I can’t recommend one over the other. All I can say is that Sudecon wipes fit in my glovebox nicely.)

Related compounds (science nerds take note!)

As mentioned above, the “active ingredient” in hot peppers is capsaicin. Pure capsaicin is 16 million Scoville heat units. The hottest pepper is the Carolina Reaper, around 1.5 million SHU. (You should definitely not vape it.)

However, capsaicin isn’t the hottest compound. That honor appears to belong to something even tougher to pronounce, Resiniferatoxin. Found naturally in a plant known as Euphorbia poissonii (what could be scary about a plant whose Latin name is poissonii?), Wikipedia writes that it “causes severe burning pain in sub-microgram (less than 1/1,000,000th of a gram) quantities when ingested orally.”

All of these compounds seem to act on a receptor in the body known as TRPV1, which controls body temperature and “provides a sensation of scalding heat and pain.” There’s also a compound known as capsazepine which inhibits the TRPV1 channel, effectively blocking the effects of capsaicin and its ilk. I’m yet to see it being marketed as an antidote to pepper spray, though.

Running on new hardware

I’ve just completed a server move, and the site should be back in business.

The old setup was a beefy server in my basement with 24GB RAM and eight cores. But access was via a jenky IPv6 connection over my cable modem, with external access via a varnish instance running at Digital Ocean. Something in my home network configuration causes that to be extremely unreliable, taking the site offline for days.

It’s now running on an AWS instance, which I hope to make an auto-scaling group. Actual content resides on an EFS volume, which is surprisingly performant. And it’s all behind a new application-style ELB, which also supports HTTPS and HTTP/2.

For now, I am using neither varnish nor a CDN, to see how it goes. Access is directly to the ELB, with every page hitting Apache. WP Super Cache should keep things pretty performant with any luck.

Clearing Chrome’s DNS cache

Most normal people will probably never even know this is a thing, but Chrome (and other browsers, really) keeps its own in-memory DNS cache, separate from what the OS keeps. For normal use, this is undoubtedly an improvement.

But every now and then, this can be a burden, and Chrome will have cached something you don’t want it to. For example, you make a change in /etc/hosts to hit a development server bypassing its load balancer or the like, but Chrome has already cached the IP, and thus the hosts change isn’t picked up.

It turns out that you can totally flush this cache—and view its contents. Just pay a visit to chrome://net-internals/#dns and voila! A listing of cache entires, and a “Clear host cache” button. (It also provides a look at how many optimistic DNS queries Chrome performs: many of the entries seem to be unvisited links on sites you’ve visited.)

Generations and their names

I hate not knowing things.

The latest? What exactly constitutes a millennial? And what’s all that Gen X/Y business?

It turns out that there’s actually not broad consensus on exactly what the date are, but they look something like this:

Generation Name Birthdate Range
Silent Generation 1925-1945
Baby Boomers 1946-1964
Generation X 1965-1979
Millennials / Generation Y 1980-1996
Generation Z 1997—Present

They tend to run 15-20 years, which means we’re around the time for needing a new term for those post Generation Z.

Also interesting to me: at the time of this writing, “millennials” are between 20 and 36 years old. I’ve taken a lot of the “kids these days” complaints about millennials to refer to teens, which would more accurately be Generation Z. Ironically, those born on or after 2000 are not millennials. (I used to assume the term referred to those born this millennium.)

The lines are insanely broad, though. Wikipedia captures this well:

For the purposes of this list, “Western world” can be taken to mean North America, Europe, South America, and Oceania. However, it should also be noted that many variations may exist within the regions, both geographically and culturally, which mean that the list is broadly indicative, but necessarily very general.

It seems that virtually no one agrees on exactly where a generation ends or begins, so you’ll see several years of variation depending on the source.