Author: azrifleman

Note to Self

Using brake cleaner to clean a gun can often help get carbon and other gunk from crevices where q-tips can’t reach. It’s also excellent at removing all oils, grease, and other petroleum products from metal.
In that regard, it’s very handy.
On the other hand, when the spatter and overspray from the nozzle happens to land on — and partially dissolve — the vinyl cover one’s wife put on the patio table to keep away dust, it’s a bit more of a liability.

Musings on RadioShack

I may be only 28, but I remember when RadioShack was a place of wonder and excitement in the pre-web days. Back then, cellphones had yet to be in widespread use, and one could buy any number of electronic components from employees who were also hobbyists and geeks.
Now, it’s a glorified mall cellphone kiosk with a few token items for hobbyists, but those are tucked away in the back, seemingly out of shame.
As a scientist and a tinkerer, I enjoy getting data on things that I’m working on. As an example, if I was building a solar array that would charge batteries, I’d want to know the current voltage on the batteries in the array (to determine state-of-charge) and the current from the panels to the charge controller and from the batteries to the load.
Going with this example, I was in RadioShack yesterday with a friend (she needed a new coin-cell battery for her calculator) and asked if they had panel voltmeters and ammeters (see here for an example) for such a system.
One of the employees thought about it, and said “No, I’m afraid we don’t carry those. Sorry.” Although not the answer I was looking for, he was honest and helpful, which I appreciate.
The other employee said, “Why do you want that? Why not just use one of the multimeters we have here?”, waving at the back of the store.
Me: “I already have three multimeters, and they all max out at 10 amps, and they can only support such currents for 30 seconds with a few minutes to cool down. I’d like something that can handle 20-50 amps indefinitely. Panel meters don’t require batteries, which is a major benefit. Also, I’d like something a bit more elegant to put into a display console.”
Employee: “Why not use one of the clamp-type multimeters we have to measure larger currents?”
Me: “The ones you have here only work on AC, not DC, which is what I’ll be working with.”
Employee: “Why not power your multimeters with a small solar cell or power them from the source and mount them in your console?”
Me, suspecting this conversation has started going downhill: “Because the multimeters are not rated for the currents I’ll need them for, a solar panel would provide intermittent power by not working at night [where knowing the state of charge is important], and the source voltage is very different from what the meter requires, as the meter runs on AA batteries. Panel meters are much more appropriate, and look quite a bit nicer.”
Employee: “Why would you need to deal with such currents at all? The biggest solar panel that RadioShack sells is a 5 watt panel that sits on your car dashboard that keeps your car battery topped off.”
Me: “I have no use for such a panel at all; my project would involve an array of big panels that would charge a battery bank that could power a small house. I’d like a permanently-wired, nice looking console that would have some meters in it so I could know, at a glance, the current state of the battery bank.”
Employee: [blank look]
Me: “Nevermind. Have a nice day.”
I have no problem with an expert (or even an enthusiastic amateur) discussing project requirements with me. Indeed, they may have a better idea of setting up such a system than I, which would be very helpful.
However, I rather dislike it when someone not only makes inappropriate suggestions, but argues about basic design goals (e.g. I want a nice-looking monitoring console, not a kludge of multimeters and wires running everywhere). Yes, I could put some shunts into the circuit and measure high currents safely with a standard multimeter; such a setup would be great for testing and bench work, but not for a final product.
RadioShack certainly isn’t what it used to be.
Fortunately, the internet allows me to order the meters I want for less than $10 each, and have them shipped to me from Thailand in less than a week. I also don’t need to interact with people like this RadioShack employee.

Fun with UPS

Last week, I ordered a case of ammo from Ammoman. It shipped on-time, and was out for delivery on Friday when the tracking page reported “THE APARTMENT NUMBER IS MISSING OR IS INCORRECT. UPS IS ATTEMPTING TO OBTAIN THIS INFORMATION.”
Odd. I called up UPS, and they had the wrong apartment number. They tried delivering to #ABCD instead of #ACBD (( Numbers masked to protect the guilty. )) Thinking that was weird, I checked the invoice from Ammoman. Turns out that I fat-fingered the keyboard when I had entered my order, and the wrong apartment number was in my order, which was dutifully provided by Ammoman’s shipping department to UPS. Oops.
“No problem”, I thought, “UPS would surely understand that typos occur, and allow me to simply correct this mistake over the phone.”
Alas, it was not to be; the sender is the only one who can change the delivery address, even when such a change is minor.
I call up Ammoman, get their after-hours sales guy, who informs me that the ladies in shipping have just left for the long weekend. I explained the situation, asked nicely, and he agreed that he’d give UPS a call. In fact, he did more — he called one of the ladies from shipping who was only a minute or two away, and she came back to call UPS. Fantastic.
After work, I checked UPS’s tracking system again, to find that the system reflected an address change. To double-check that everything was in order, I called UPS. Evidently Ammoman provided the correct apartment number, but UPS screwed up, and simply removed the apartment number from the delivery address. Somehow, I suspect my condo’s management office won’t know what to do with a case of 5.56mm NATO.
UPS insisted they couldn’t do anything, as the shipper needed to make the call. I explained that the shipper had made the call, even after they had closed, and UPS screwed it up. I politely insisted that it’d be much easier all around if they simply corrected the address and attempted to deliver again today (after all, it was still on the truck and they can wireless update the driver’s tablet). After some time on hold, they said it’d be impossible.
“Fine”, I said, “just have the local depot hold the parcel for pickup, and I’ll get it tonight before I fly out to a friend’s wedding.” The agent says she’ll try.
The agent calls the local depot and, sounding excited, announces that they’ve been able to update the address, and they’ll deliver the package on Tuesday! What, Tuesday doesn’t work for me, because I work in Tucson and won’t be in town to pick it up until the next Friday? I wanted it held? Oh, I’m sorry, that’s impossible; after the sender made the change of address, there’s no way for them to hold the package.
I explained that attempting re-delivery would be futile, and it’d be much simpler to just hold it for pickup, and would they please call the local depot to ask if they’d do it. After another interminable delay on hold (frequently interrupted by the agent apologizing for being on hold — I don’t care about waiting, it’s fine, don’t bother coming back on the line unless you have something informative to say), they said the local depot would hold the package and, in fact, would call me directly to make sure they got everything straight.
A short while later, the depot called and everything seems to be in order. They’ll hold it until next Monday, and my wife (( I’m still getting used to saying that. )) said she’d stop by sometime after work (she works in the same town where we live, and can stop by the UPS depot later in the week) to pick up the ammo.
Moral of the story: check your address prior to submitting an order. Spending 10 seconds to check that everything’s correct beats 30 minutes on hold with UPS. The local depots are considerably more flexible in dealing with various issues than the corporate call-center people. Also, Ammoman’s shipping ladies are awesome. I should send them flowers.

Sparky Fun Times

My friend’s roommate’s car battery died last week. Since she rarely drives the car, it was easier (and quicker) to remove it from the car and hook it up to a charger, rather than jump start the car and have her drive it around.
My little Battery Tender Jr. has been charging it for a few days, but it’s only able to output about 750-900 milliamps (( The specs say 750 mA, but it seems to deliver about 900 mA in bulk charging mode. Odd. )), so charging a car battery takes several days.
I also happened to have another “smart” charger that can put out about 1.5 amps, so I brought it over to their house tonight and had my friend connect it. During the process, he managed to accidentally short the negative connector on the quick-disconnect end of the alligator clips (looks like this, but unfused) to the positive battery terminal. Lots of sparks ensued.
Fortunately, he disconnected the alligator clip quickly, so no damage was done, but it was rather fun for a second or two.
After being connected properly, things seem to be working quite well and the battery (should) be ready to go tomorrow afternoon.
Moral of the story: Don’t short car batteries. They can output a massive amount of current.

Missing Things

The brain is evidently really good at identifying things that it likes or dislikes when it’s presently sensing them.
However, my brain in particular seems to be really bad at recognizing things that it’s missing. I get a vague feeling of “Hmm, I miss something, but I can’t quite put my finger on it…”
After some thought, I think I’ve figured it out. I miss winter and the smell of pine trees. Living in the desert, I don’t really have many pine trees around, and I miss that.

Inconsistent

I’m a big fan of BJ’s Brewhouse, a restaurant chain with tasty food and delicious beer (( Try their red. It’s outstanding. )).
There’s now two in Tucson. The first one, which is on the north side of town, used to have a “gun busters” (warning: PDF) sign, but after some polite prodding by the citizenry, they took it down — permit-holders are not forbidden from carrying there, so long as they don’t drink. There’s been no incidents of violence, gun-related or not, at the restaurant that I’m aware of.
However, the newly-built BJ’s on Broadway has a “gun busters” sign. A polite letter asking the management to remove the sign, like the other restaurant, has been dispatched to the management. I urge others to do the same.