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.

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.

Cleanup

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.

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.

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.)

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:

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.