How to install that .deb from a .tar file

Eventually you’ll forget.

It’s an idea to go through the README file. Configuration flags exist in those sometimes, but usually cd-ing into the DEBs folder is what’s needed. Try this

at which point typing

might be wise should you decide to do something about your old variable path. From the first code block, the -xvf variables simply mean eXtract, Verbose (display action on terminal), and File archive. Note that installing a program by the DEBs method has a probability of changing a configuration or a path variable somewhere. You will not notice the effect until maybe two or four years into the future. It will probably happen when you upgrade your machine to the next major version. Try not to update things during study week or before a big presentation.

Have fun!

random notes on mosfets and question on when i may see movie x or y

Author’s Note: not so much a blog post as it is a list of random thoughts. I know, I know, I could’ve made more pretty equations, but I typed this on a note pad, and now it’s 3:17 in the morning.

Stuff that I should have understood last month:

logic level transistors are transistors that can be turned on (or off) by a Voltage_gate-drain voltage less than or around 5 volts. This allows it to be controlled augmented (or regular) MCUs like arduinos and Rasperry pi without needing to amplify the voltage on the pwm signal.

Pick N-channel and P-channel, either with enhancement modes

Simple equations on making sure your MOSFETs don’t burn up. (otherwise stated: “Do I need to heat-sink this?”)

via Joule heating if

P = i2*Rds , where Rds   is the drain source resistance which is based on gate voltage.

And if your mosfet current form source to drain works at.. idk. 6A, and has a Rds = 0.6667 Ohms value than power consumption is

P = 2.4W

Pd = (max(Tj)-TA) / R_tethaJA, this is max power mosfet can dissipate, where Tj is the junction temperature, and Ta is the ambient temperature.

P = 175-25C / 62.6 c/w, 25c is ambient temp.

then Pd = 35mW which is less than 2.4W

so you’re safe to operate without a heatsink

Vgs or Vth



Pd = as above

mosfet shouldn’t have a very high ON high resistance


I don’t need to worry about using an opAmp inverter (which can go up to 5$/USD!) to get inverted voltages to drive a PNP MOSFET.

However, issues exist when the logic voltage is 5V on the MCU if my Li-Po voltages vary from 9 to 11.1 to 12.75 volts. [9V-12.75V] is basically my absolute range in order for things to be safe. Less than 9Vs (or less than 3V per cell) and you’ll have to pay a visit to the trickle charge fairy. (Less than 2.X V and some chargers will refuse to charge them). More than 12.75V (or 4.24V/cell) and your Li-Pos could could get damaged in some other way.

Anyways, if the source is at 11.1V and the gate is at the max possible voltage of 5, then the difference is 6.1V. The PNP will forever remain on high and never close.

According to this

I can use use a simple BJT to account for the difference. In this case, I only care about the voltage, not the current. Actually, I doubt that little transistor can handle more than an Amp. According to the secs,

that’s a definite no on going over 1A. So the in-series resistor would have to be something that limits the current going through it. Something not in those URLs Is where said resistor could be placed. In theory, I should be able to place a resistor in series to the 2n3904 on the ground side to limit current as low as possible, but also to keep the voltage value at the source to as close to the 11.1V (incoming voltage source value) as possible. I mean, in my head (and I haven’t drawn this out in paper yet), that should work. I don’t want the li-pos to drain current while any particular MOSFET is off, so ideally that resistor value should be high.

Further, using a transistor to control another transistor will add in some extra delay on the PWM side of things. I’m leaning towards using the 2n3904 to simply on/off the PNP MOSFET.

Oh, the application for all of this is a Peltier h-bridge. e.g. an electric-thermal device.

So the input would be digital (1 = HIGH, ditital 0 = LOW) –→ 2n3904 –→ PNP

While on the bottom 2 NPN MOSFETs, the full fury of a the PWM input will be direct driver of them.

I hope this makes sense. If it doesn’t, it’s because I didn’t put up any specs, it’s 2:24 in the AM, and my equations should probably reference specific pages on particular datasheets. Right, if you didn’t understand it, it’s because it’s my fault. That’s what some professors say anyways (“I’m sorry I didn’t explain it well, let me try again”) If I were lecturing, I would be like, pay attention kiddo! I’m only going to go through this once. Blah blah. So, if you were wondering what was on my mind this weekend, it was on this. These were some of the things that I should’ve known last month, but didn’t until recently.

Hamilton is coming to town around May. Ticket prices are already at the 800USD+ range now. The good seats are gone, and the remaining ones range between 1.1K-1.2K. Assuming one takes their S.O. to such a play, we’re talking about paying between 1.6k-2.4k… $_$. Here’s the thing about going to see Hamilton. If you take a girl to see it, she better be your girlfriend, or fiancé, or wife, or something that places the ‘significant’ in the S.O.  Buy your tickets now, and the lady friend you’re seeing could be very well be seeing  some else within 2-3 months. It’s not for the light hearten relationship. If a guy takes you to see Hamilton, that’s a serious date. That’s a, “hey, will you marry me date?”, not a “Hey, will you be my girlfriend date?” So, here I am wondering.. Screw S.O’s. I’ll go see Hamilton myself. Alone. Solo. But who does that? I’ve went to see movies solo before (sorta like a dating yourself type of thing), but that’s only ~15 bucks. Seeing a play is more like a social event between viewers when you’re dropping that much. I guess the only thing left to say would be:

When movie X came out, some of my friends had already seen it. It was really a family event for some of them (inter-generational type movie). A few of them had even went on to see it 1, 2, even 3 times. I eventually went to see movie X with my own family. I guess, I’m bringing this up because, that same afternoon I had a breakup with a person in my life. We had spoken, made plans, canceled, made more plans, on watching movie X. Tickets may or may have not already been purchased by me. I had planned to go watch it twice. Once with family, the other with the aforementioned. So here I am, comparing movie X tickets with Hamilton tickets. As 45 would say; sad.

How does that tie in to today? I’ve tried asking some people if they wanted to watch movie Y. Similar story, many folks have already seen it (my folks already went without me!) at this point. The longer I wait the subset of friends I have who would have seen it and wouldn’t bother seeing it for the n-th time with me decreases. It’s been Z weeks now. I think I’ll just go watch it myself.

Or.. Maybe I’ll go see it next week? This is supposed to be a hell week for me, a 4 hours of sleep every day type of week. Not really though.. I mean, I don’t need to go to the coding challenge thing on Tuesday, and I don’t need to go to the hackathon thing next week. I sorta need to go to the hackathon thing this weekend though since since tickets have already been paid for.

3/5 Monday: Dr.K meet, design stuff, lecture, design stuff, tech event that ends at 9pm (but I only need to spend 20 minutes there if any at all).

3/6 Tuesday: Dr.R meet, design stuff until whenever (cancel? Go watch movie Y?)

3/7 Wednesday: hackathon stuff, lecture, design stuff

3/8 Thursday: design stuff (end night watching movie Y?)

3/9 Friday: hackathon stuff (fuck sleep)

3/10 Saturday: hackathon stuff (no sleep)

3/11 Sunday: hackathon stuff (sleep? Lol), end night with design stuff

3/12 Monday: Dr.K meet (again), lecture, hackathon #2? (I still need to do design stuff), prep presentation

3/13 same as 3/6, prep. presentation

3/14 similar to 3/7 but team needs to present

I’m not obligated to do hackathon#2 (and now I see why hackathon#1 cost money to get in) from the 12th-16th, so I might cancel that event depending on how much progress on my ‘design stuff’ gets done. How ready my ‘design stuff’ team is on our presentation on the 14th will be the determining factor for that. This leaves tuesday or thursday for movie going this or next week. Hopefully movie Y is still screening by then. Off to go check Fandango.

On Auctions

Author’s note: Just some of my notes and thoughts on doing homework before an auction

Check VIN number from wind shield to compare to VIN number in other locations such as door and trunk. They should all match.

Check the dip stick.

Flooded cars should be avoided

Edmunds – tends to give an overall average. Prices are usually somewhere in between what a private seller and a dealership would offer for it.

[damaged, rouge, average, clean, outstanding]

Kelley Blue Book – favors car values towards the dealer. So people will start at the KBB price and negotiate down based on depreciation and other factors. Prices tend to be higher than what private seller would sell for. Don’t expect to pay the KBB value in most cases.

[fair, good, very good, excellent]

National Automobile Dealers Association (NADA)

Dealership trade in value for cars use

* Wholsale Blue Book – the most money a dealer would pay for a car

*The Manheim Market Report – averages 1k’s of sells of cars sold in auctions.

There’s also a Black Bluebook, but this uses weekly wholesale auction values. These prices are lower than trade-in values.

Because, you, me, and everyone else has a life, we don’t want waste time searching through endless pages and dealing with ad consuming page downloads.

TNT auction –

there is no preview of airport lost and found.

They uploaded their car listings to

this view gives the items under their sell order. e.g. (Sale Order: 6 of 325)

* not everything is a car. Some trailers are listed too.
This is the .pdf for the miscellaneous items listings

Clark County holds a surplus auction three times a year. They contract TNT Auctions to do this for them. Two auctions are held simultaneously. One is the miscellaneous items auction and the other is the car auction. One may register as a bidder on-site from the TNT trailer. There’s no registration fee. Just show a valid form of ID to receive a bidder’s card. Miscellaneous items like electronics or office equipment cannot be bid on online, only in person. If you bid in the car auction in person, you must register in person. If you want to bid for the car auction online, you need to register online in the TNT Auction website. There’s same day registration, but you’re encouraged to register during the preview and pre-registration period.

For those bidding on a vehicles, the preview period is the time to inspect the vehicle. Inspect engine, put the vehicle into gear (they allow you to get in?), listen to the motor run, and check the gear. Individuals may not move the vehicle. Raise hand into air, or raise your bidder’s card.

10% buyer’s fee when bidding live

13% buyer’s fee when bidding online. The extra 3% probably covers banking fees, but if that’s the case, what difference would it make compared to using your credit/debt card in person? In which case, it probably covers some fee the TNT website adds for their ‘internet services’.

After you win the bid, you must deposit $300 for vehicle by the end of the same day. By the following Monday before 2PM. You must pay the remaining balance. With that done, you’re handed the keys and the vehicle title. It’s up to the winner to smog check the vehicle and to register it with the DMV. Miscellaneous items winners must pay in full and remove the item from the same day.

There seems to be an understanding that car auctioneers will lie about the condition of the vehicle. There’s also concern that you might get a ‘flood’ car, which might require investments to get fixed if it’s even possible. Basically, “as if” is the phrase to remember when buying.

What I’m doing right now:

1) I was going to do some wget magick to automate the process of getting the entire listing of what’s up for auction.

2) Then I was going to phrase the data and export it in a spreadsheet friendly format

3) Then I was going to conduct analysis cross referencing each Car’s Make, Year, Model to averaged values from the above “blue book” websites (which I would also have a set-up to automate retrieval using their APIs or through less respectful methods)

4) Then I was going to use a report I wrote on calculating depreciation using this year’s interest rate, and run Monte Carlo simulations to… to…

Was* is the take away word. For now, I’m just going to manually select a few items from the listings, and get a blue sky value for them. That report on calculating depreciation, I did write it (along with a co author). I’ll find it later. Was it depreciation? Maybe it was on financing a loan? I forget these things sometimes. Anyways, that’s all for today.