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alexpgpIt's been that kind of day.
My workload was involuntarily eased when someone, somewhere, realized that over half of what had been assigned to me had already been translated! And a long time ago, as well!
Thus it is that St. Jerome, patron saint of translators (and, some would say, of bloggers, though St. Augustine, St. John the Apostle, and St. Isidore might also qualify for the honor), protects - or perhaps punishes - his own.
The news came at an opportune moment, with the assignment of another document, yet one more "radiogram," which makes up for part of the lost volume and is due tomorrow.
* * * I've been looking for my multimeter for the past couple of weeks, but haven't been able to find it. This is not surprising, considering the baseline lack of organization around here (compounded by Parties Unknown™ rearranging quite a bit of my stuff while I was last in Baikonur). Heck, I am fortunate in being able to find my backside around here without having to resort to a map, a compass, and Google.
Anyway, I stopped by the local Radio Shack to see what they had in the way of multimeters, and was greeted by one of the store's minions upon entering.
"Hi, how can I help you today?" says the young man.
"I'd like to look at some multimeters," I say, after which the conversation skips a noticeable beat.
"What're those?" he asks.
Good old Radio Shack! ("You have questions. Wehave answersdon't know what you're talking about!")
* * * You see, while surfing I've seen DIY pages showing how some enterprising folk have basically put a 5-V regulator between a female USB socket and a battery to provide hours of power to devices that require such power through such a connector. Most of the plans involve a 9-V battery as a source, which on the one hand would allow you to cram the entire assembly into a small Altoids chewing gum tin, but on the other seems pretty much a waste of battery power.
According to information at TigerDirect.com, your typical Energizer 9-V battery is rated at 9 volts and 595 mAh (a measure of current multiplied by time).
But if I were to wire five rechargeable, nickel hydride AA batteries in series, each of which has a voltage of 1.2 volts and a capacity of 1200 mAh, I'd have a 6-V source (instead of a 9-V one) with 6 Ah of capacity.
Unless I've forgotten all of my electrical science (not unlikely, but still), that'd mean less waste heat out of the regulator (which takes whatever voltage you put in between 5 V and about 35 V, and knocks it down to a rock-steady 5 volts, producing waste heat roughly in proportion to the excess input voltage) as well as the ability to power something like an iPod Shuffle, or a Contax camera, or a Sharp Zaurus for significantly longer than the 9-V battery. The downside: five AA batteries take up more space and weigh more. I'd be <gulp> forced to cram it all into an Altoids mint box!
Sounds like a fair trade to me (not to mention I have about 20 AA NiMH batteries collecting dust around here).
Cheers...
My workload was involuntarily eased when someone, somewhere, realized that over half of what had been assigned to me had already been translated! And a long time ago, as well!
Thus it is that St. Jerome, patron saint of translators (and, some would say, of bloggers, though St. Augustine, St. John the Apostle, and St. Isidore might also qualify for the honor), protects - or perhaps punishes - his own.
The news came at an opportune moment, with the assignment of another document, yet one more "radiogram," which makes up for part of the lost volume and is due tomorrow.
Anyway, I stopped by the local Radio Shack to see what they had in the way of multimeters, and was greeted by one of the store's minions upon entering.
"Hi, how can I help you today?" says the young man.
"I'd like to look at some multimeters," I say, after which the conversation skips a noticeable beat.
"What're those?" he asks.
Good old Radio Shack! ("You have questions. We
According to information at TigerDirect.com, your typical Energizer 9-V battery is rated at 9 volts and 595 mAh (a measure of current multiplied by time).
But if I were to wire five rechargeable, nickel hydride AA batteries in series, each of which has a voltage of 1.2 volts and a capacity of 1200 mAh, I'd have a 6-V source (instead of a 9-V one) with 6 Ah of capacity.
Unless I've forgotten all of my electrical science (not unlikely, but still), that'd mean less waste heat out of the regulator (which takes whatever voltage you put in between 5 V and about 35 V, and knocks it down to a rock-steady 5 volts, producing waste heat roughly in proportion to the excess input voltage) as well as the ability to power something like an iPod Shuffle, or a Contax camera, or a Sharp Zaurus for significantly longer than the 9-V battery. The downside: five AA batteries take up more space and weigh more. I'd be <gulp> forced to cram it all into an Altoids mint box!
Sounds like a fair trade to me (not to mention I have about 20 AA NiMH batteries collecting dust around here).
Cheers...
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Date: 2006-02-15 01:04 am (UTC)For example I built a PocketTracker (http://www.byonics.com/pockettracker/) that transmits GPS APRS data on a 144.390 signal. It is built in the proverbial Altoids tin and uses a 9v battery and a regulator. A later version uses a large enough regulator to power the GPS as well. I've easily gotten to Monterey from here - a good 40 miles or so - just using a little rubber duckie antenna. And the battery life seem to be quite good - they claim it will run for 4 days on one battery.
On the other hand, my Canon scanner is USB-powered, and I'd sure hate to try to run that off a 9v battery - I think it takes half an amp or something ;)
Keep in mind, though, that simple LM7805 regulators require several volts of headroom, so getting 5vdc regulated from a 6v battery pack probably won't work. You have to figure 1.3 volts per cell at the lower end, and if the required headroom is 2 volts, that's 7v/1.3v = 6 cells, which would fit in a Radio Shack 8 AA plastic holder.