Barnson.org

http://www.time.com/time/magazine/article/0,9171,1818197,00.html

I’m not big on churches, but as far as churches go, that’s pretty darn cool.

Quote of the day from What Women Know:

We distrust separate-but-equal rhetoric; anyone who is regularly reminded that she is “equally important” is probably not. Partnership is illusory without equal decision-making power.

hey guys.. the second trailer for the flick (directed by l’il ole me) is ready to be seen and hear your feedback!! Or rather I want feedback. the trailer has no feelings.

http://youtube.com/nvzmovie

I have, literally, nothing else to say except this one word.

Awkward.

http://www.icann.org/en/announcements/announcement-4-26jun08-en.htm

ICANN yesterday agreed to start in 2009 with letting any word replace the ubiquitous ‘.com’ tag in internet addresses. Some articles stated that it will start a scramble for top-level domains with a preexisting high-attraction factor, ultimately causing businesses to buy thousands of domains to protect their internet turf.

What do you guys think? Do you really think a whole new frenzy will result?

The general public currently recognizes domain names around entity status (for profit, non-profit) and geography (country of origin). This is obviously shattered as now a host of new categorical structures will be applied with the new domain pairings. For example, www.hotsex.barnson is a sure winner in the new open domain name age.

Without putting too much thought into this, my feeling is that most people with a personal website won’t move to change or protect their internet position. I’m sure that some businesses will want to expand their digital territory to protect their https. New ventures will certainly want to take up interesting pairings to enhance notoriety.

Thoughts?

I really, really hope Matt’s days are like this: http://www.thewebsiteisdown.com/

My $.02 Weed

Do you guys think oil prices will ever peak? Or is it just going to keep going up till nobody can afford to drive?

OK, the article is way old, but I just ran across it yesterday. It’s an entertaining, opinionated look at what a PC power supply is, what is should be, and why you should (or shouldn’t) care:

http://www.dansdata.com/top420p4.htm

Thoughts: 1. You are sure the 2S pack is in serial to the 12S pack, and only the whole 12S bundles are in parallel to one another? I know, I know, this is a fairly obvious question, but deserves asking. 2. What’s your total wire length for each pack, and for the parallel/serial connectors per pack (if you’re using something like a Dean’s parallel/serial board or Anderson Power Pole, note that too)? 3. Can you take a picture or two of your setup and post it? Ideally, post one picture of how you are connecting your batteries to the ESC (probably easiest to show without being in the heli), and post another picture of how they are connected when you are charging. 4. What gauge of wire are you using on your 2S and 10S packs? What’s the total length of wire (including both sides, wire under shrink wrap as well as exposed).

My initial reaction is that you may be seeing the result of varying resistance values across the pack wiring (which highlights some of the problems of ganging separate packs versus building a single, uniform pack). Let’s do some math.

Assumption 1: Your batteries are all using 16-gauge wire with a resistance of .00473R per foot. Assumption 2: Your 2S packs have only a total (both + and – sides) of 1 foot of 16-gauge wire before reaching the serial Y-connector, while the 10S pack requires a total of two feet of the same wire. Assumption 3: Your peak draw is a combined total of 100A, or 50A per 12S ganged battery. Assumption 4: We’re operating at around 77F temperature. Assumption 5: Your 16-gauge wire is industry-standard, with a a loss of around 122.3 feet per ohm. Assumption 6: Your batteries are hot off the charger, running 3.6v apiece.

Voltage Drop (V) = Amperage(I) * Resistance(R)

10S battery: V = I * R V = 50 * (.00473 * 2) V= 0.473v drop purely due to line resistance

2S battery: V = I * R V = 50 * (.00473 * 1) V = 0.2365v drop due to line resistance

So a difference of one foot of length of 16-gauge wire is a loss (resistance) of a quarter of a volt. So to see why your 2S battery might be delivering more amps, your 50A draw results in the total voltage across both packs dropping to 2.9 v/cell on average, but the 2S pack will be delivering substantially more amps due to the higher voltage to the Y-connector, thus the actual voltage of the 2S pack will be sagging more… In short, it is delivering substantially more current to the motor than the 10S pack.

You should be able to see this, ideally, with two wattmeters in-line prior to the Y-connector, one per side of the ganged serial battery. You could also do what I do: build two identical shunts, pick up a pair of identical $3 digital multimeters from Harbor Freight, and watch what happens.

I’ve also ignored the electrical loss due to the inter-battery connectors within your 10S pack. There’s a lot of extra metal connecting those batteries, with its own electrical loss. Steel is not a great conductor.

Tips: 1. If you are ganging packs, make sure the wire for all packs are exactly the same length to the Y-Connector, exactly the same gauge, and preferably the same make/manufacturer, purchased around the same time. You might possibly wish to allow a slightly longer connector for the lower-voltage packs due to the intra-pack electrical losses. 2. If possible, use the same-size packs or similar-size packs. For instance, I use four 3S packs as a 6S2P in my trainer setup. This way, your intra-pack electrical losses are similar or identical. A friend gangs 2S and 3S packs using Anderson Power Poles to create whatever voltage he needs. Because there’s just one extra tab on the 3S packs, the intra-pack losses are only very slightly different (30% more). On a 10S pack of A123 cells, you have five times the electrical resistance within the pack than you have on a 2S pack. 3. You could try soldering copper bars on top of the 10S pack steel tabs. This would reduce intra-pack electrical losses, resulting in higher voltage to the Y-connector. 4. Measure the total resistance using a multimeter, from the tip of the end of one pack lead to the tip of the other pack lead. Make sure there is no circuit engaged when testing this, or you will obtain false readings and possibly damage your meter. After measuring the resistance of your 10S pack, re-solder leads to your 2S pack, and then start trimming the wire until you have just as much overall resistance on your 2S pack as your 12S pack.

I don’t like Option #4, since I’m not totally sure about the effect of the internal resistance of the batteries themselves on voltage disparities to the Y-connector, but I think it should work for the goal of delivering identical volts at the Y-connector. I prefer to use similar-size packs (3S and 2S) so that I don’t have to deal with, you know, science and stuff 🙂

In the latest bout of White House douchebaggery, the White House forbids anyone to open an email from the EPA suggesting that greenhouse gases are a pollutant. Yep, disagree with the findings before you even read the report, and forbid anyone to read it because you disagree with it without reading it? Sure, sounds like an open-minded, American approach to me.