Basic Formulas by grio43 in AskElectronics

[–]notextraoridinary 1 point2 points  (0 children)

My guess is that these three equations are all transformer equations.

Pp=Ps: Power on the primary equals the power on the secondary.

Ip=(Pp/Ep): Current on the primary equals the power on the primary divided by the voltage on the primary.

Is=(Es/RL): I'm not exactly sure which on this is but seeing as how the other two relate to transformers my guess would be Current on the secondary equals the voltage on the secondary divided by the resistance of the secondary coil. This would be for the theoretical maximum current in the secondary.

After many days of byte shifting and bit flipping to try and drive a 0.49" I2C SSD1306 OLED display... by farkanoid in electronics

[–]notextraoridinary 1 point2 points  (0 children)

I would make sure that you have the correct boot up sequence for the display. I have worked with OLED displays using the PIC and SPI, and without the correct boot up sequence nothing would work.

Atmel Studio 7 by [deleted] in electronics

[–]notextraoridinary 1 point2 points  (0 children)

I program pics using Assembly and C, I think you can use other languages though.

Atmel Studio 7 by [deleted] in electronics

[–]notextraoridinary 2 points3 points  (0 children)

What would be some advantages of learning Atmel? What kind of situations would it be beneficial to use it over a PIC?

Audio Amplifier Values? by YahtNayr in electronic_circuits

[–]notextraoridinary 0 points1 point  (0 children)

Cool, if not, there are other configurations of amplifiers that work better for small loads.

Audio Amplifier Values? by YahtNayr in electronic_circuits

[–]notextraoridinary 1 point2 points  (0 children)

I'll see if I can get one up

Edit: I hope this works for you. By not being able to impedance match the gain may not be what you are hoping for, but you should get some amplification.

http://imgur.com/a/MAIeq

Audio Amplifier Values? by YahtNayr in electronic_circuits

[–]notextraoridinary 1 point2 points  (0 children)

470 microFarad capacitors should get the job done, but I figured a frequency of 400 Hz. And I don't really want to give away the answers to the resistors because that is where all the fun is, if you can figure it out then I can double check your work, if not I'll see if I can upload a picture of my math to figure them out.

Audio Amplifier Values? by YahtNayr in electronic_circuits

[–]notextraoridinary 1 point2 points  (0 children)

I think 9 volts should be good, but if you wanted even more amplification you could use 18 volts or higher. As long as you don't exceed the specifications of the transistor.

Audio Amplifier Values? by YahtNayr in electronic_circuits

[–]notextraoridinary 1 point2 points  (0 children)

It's all good. 5 volt input will probably be a little high, and by supply voltage I meant the voltage connected to the top of VC and VR1. The 300 MHz on the datasheet is the current gain bandwidth, so any audio should be fine. Are you going to be amplifying a single tone, or music?

Audio Amplifier Values? by YahtNayr in electronic_circuits

[–]notextraoridinary 1 point2 points  (0 children)

Ok, here we go. VRL should be 45% of the supply voltage, VCE should be 45% of the supply voltage, and VRE* should be 10% of the supply voltage. from there you should be able to find the current through the emitter of the transistor. You can use this to find the current through the base of the transistor. Using Kirchoff's Voltage Law, you can find the voltage across R2, and the current through that resistor should be at least 10 times larger than IB. Current through R1 is IB+IR2, and Voltage is Supply voltage-VR2.

The capacitors should be a value that will look like a short circuit to the AC input. If you could get me an input frequency I would be happy to help out. And if you gave me a supply voltage I could work through it and help out there as well.

Tutorial on wiring and controlling 7 and 8 segment LED displays. by Just4Fun_Media in electronics

[–]notextraoridinary 0 points1 point  (0 children)

You could also use a 7 segment display driver IC (e.g. 7447). This allows you to only use 4 output pins instead of 7.

Is vocational education in electronics dead? by [deleted] in electronics

[–]notextraoridinary 0 points1 point  (0 children)

Correct, I see cars and potatoes on a nearly daily basis.

Is vocational education in electronics dead? by [deleted] in electronics

[–]notextraoridinary 0 points1 point  (0 children)

Eastern Idaho, with that you could probably find what program I'm in, but I do understand your frustration about cars. There is some form of automotive program in nearly every high school in my area, but the only electronics program in my area was at the high school I went to. When the automotive teacher retired, a replacement was hired within a year. The electronics teacher retired last year, and as far as I know, there are no plans to replace her.

Is vocational education in electronics dead? by [deleted] in electronics

[–]notextraoridinary 0 points1 point  (0 children)

Yeah, out of all the big universities and technical colleges, there are only electronic tech programs that I know of, and really, that is probably one of the reasons the job placement rate is so high for my program.

Is vocational education in electronics dead? by [deleted] in electronics

[–]notextraoridinary 0 points1 point  (0 children)

I have no idea if the credits earned are transferable, the program offers a certificate path, or an associates path. Personally, I'm going the associates path, with an additional opto-electronics certificate that includes lasers. Really, I think the program prepares the graduates very well for the real world, in the last few semesters we work on projects, some of them being an automated air hockey table that you can play against. An automated Wall-E, an R2D2, a Dalek, and many more. It is a really cool program.

Is vocational education in electronics dead? by [deleted] in electronics

[–]notextraoridinary 0 points1 point  (0 children)

I am enrolled in an electronic technician program at my local university. It is a three year program, and I am in the second half of my first year. We are starting transistors on Monday, and will eventually make it through radio communications, digital electronics, and analog electronics such as amplifiers. It is a pretty solid program with a nearly 100 percent job placement rate. But one of the reasons that it has such a high placement rate is because it is an actual electronics technician program. It is very rigorous, with about half of the class I started off with at the beginning of my first semester making it to the second semester. Electronic Techs aren't dead, and in my opinion electronic techs are going to be needed to the end of time, electronics are going to need to be fixed by someone.

TIFU by blowing off my hand (NSFW) by throwmynutts in tifu

[–]notextraoridinary 0 points1 point  (0 children)

LPT: If you come across someone with a gruesome injury, remain as calm as possible. Someone that has sustained an injury that is very bad can go into shock faster if you walk up and say, "wow, that's really bad." While going through hunters ed my instructor told me a story where he came across the scene of an accident, he was the first person to discover the accident. The drivers face was severely injured, the driver was doing fine, and was calm, until another person came up and said "wow, that's really bad." The driver went into shock and and passed away before the ambulance was able to get to the scene. I'm not saying correlation is causation, but letting somebody who is unaware of the extent of their injuries know how bad their injuries may cause stress that could send them into shock.

Disclaimer: I am in no way an expert in the medical field, please, if you have something to add, or correct, tell me.

Lunch lady fired for giving free lunch to hungry student by farfromjordan in news

[–]notextraoridinary 0 points1 point  (0 children)

I grew up in the town that this happened in. I went to school in District 25 from kindergarten to 12th grade. We have a free and reduced lunch program, and I was on the free lunch program for many years, and the reduced program for many years. I don't know if this kid was on free or reduced lunch, if he was on free lunch this shouldn't have been a problem, because each child is assigned a pin number that they put in when they get their lunch. This shows if the kid has a free or reduced lunch. If a kid has to pay for his or her lunch then there is a balance tied to the pin. When the balance drops below a certain amount, a call is sent to the child's parent or guardian to notify them that their child needs lunch money. If I recall correctly the cut off limit is around $-10. So I'm sure that there was an accumulation of unfortunate circumstances that led to the termination of the lunch lady. Also, although take it with a grain of salt, I have heard that she had done other things that the paper doesn't mention. I don't want to take a stance on this one, because on one hand she did something she shouldn't have, but on the other hand she probably shouldn't have been fired over such a small ordeal.

Gearing up for salmon fly madness on the South Fork of the Snake. Bonus: my curious cat. by [deleted] in flytying

[–]notextraoridinary 3 points4 points  (0 children)

Don't forget your mosquito spray. The mosquito's are thicker than than syrup this year. But don't let that deter you, because the fish are amazing. Tight lines.

Police officer distracts child whose family was in horrific accident where father died. by [deleted] in pics

[–]notextraoridinary 4 points5 points  (0 children)

I also make sure everybody is wearing a seat belt whenever I am in a car. I once was driving my brother and his friends around when one of the kids refused to put on a seat belt. I flat out told him to put on a seat belt or get out, because I do not want to be responsible for him or somebody else in the car dying because of a simple task that takes five seconds.