Electrical Engineering V3 - Developers

[QUOTE=Dolton;50710295]I sense a fire in your future. Make absolutely sure you are charging the battery correctly and not just slapping some random power brick onto it that happens to match the voltage. It looks like it is a LFP which is safer than a LiPo (which will explode if you glance at it funny) but still use caution when charging it.[/QUOTE] The battery charger came with the battery. I also message the seller. "wiring Battery pack has four lines, two red, one thick, another thin, two black line, the same one thick, another thin, thick black line and red line is the negative and positive for discharging, thin black line and red line is the negative and positive for charging,so the thick black and red line be connect to the motor’s cathode and anode, the thin black line and red line should be connect to the charger’s positive and negative".

Fuuuck. Something in my pincushion circuit failed. [IMG]http://i11.photobucket.com/albums/a166/ballsandy/New%20Bucket/IMG_5278.jpg[/IMG]

Maybe you need to add in offsets for each lens depending upon how far off center (of the screen) each lens's center is.

Pincushion adjustment is performed using around 50 pots on an external PCB. Thankfully I have the service manual for the set so I know what each adjustment does. First however I need a cleaner workspace to do the adjustments in. It's more that when this was first tested there was no pincushion so either I've missed a cable or part of the circuit itself has failed from being roughly stored.

Speaking of that PCB... [IMG]http://i11.photobucket.com/albums/a166/ballsandy/New%20Bucket/IMG_5317.jpg[/IMG] Yeah, that would do it. [IMG]http://i11.photobucket.com/albums/a166/ballsandy/New%20Bucket/IMG_5319.jpg[/IMG] I must of also touched some of the adjustments over the last year or so. Oh god this will be fun. [IMG]http://i11.photobucket.com/albums/a166/ballsandy/New%20Bucket/IMG_5320.jpg[/IMG]

Found a child's 24V "Razor E150" scooter in a dumpster yesterday. It was missing some parts including the two 12V 4.5ah sealed led acid batteries. I don't have many tools and stuff at my gf's apartment. I did however have my two 21V Dewalt power tool batteries... and I didn't want to under power it by 4 volts so I put both in there in series. So now.. I have 42V electric scooter! Despite it being for ages 8-11 and having a weight limit of 120lbs. It has some decent power with a 22 yr old 165lbs rider. It's actually a bit scary. Once the motor cools down and my batteries are done charging, I'm gonna see what speed I'm moving around at with my phone. [T]http://i.imgur.com/dJ8HfR9.jpg[/t] [T]http://i.imgur.com/CNaKYxT.jpg[/T] [T]http://i.imgur.com/FZtctcW.webp[/t]

These things makes me want to get into electrical engineering. By the way, I think I got it. [img]http://i.imgur.com/TvMem2s.png[/img]

[QUOTE=pentium;50717612]Speaking of that PCB... Yeah, that would do it. I must of also touched some of the adjustments over the last year or so. Oh god this will be fun. [/QUOTE] I bought myself a CRT projector in 2008. It's an NEC PG 9+ from curtpalme.com. It will go to 1920x1080 progressive but struggles a bit so I run 1600x900. It was giving me some issues and had physically leaky caps so I recapped everything except the power supply at this point. It's heavy as fuck and takes up a lot of space but the image quality is amazing. And the first time setting up was so incredibly overwhelming it took me days to get an acceptable image. I have it down to about 2 hours from scratch and made my own setup procedure for it [URL="https://www.dropbox.com/s/6eb7qfohpqcdb0o/Complete%20Setup.odt?dl=0"]which you can look at[/URL] to see what's involved. This model and some other models of CRT projectors could accept a camera for automatic convergence. I believe you would interface it with software running on a Windows 3.1 machine and as long as the the red and green tubes were aligned mechanically, it could automatically adjust their geometry to match the green tubes. [IMG]http://i.imgur.com/TnoAGBd.jpg[/IMG]

Well now I've either really fucked the convergence up or I've blown one or more of the convergence amplifiers. :suicide: [IMG]http://i11.photobucket.com/albums/a166/ballsandy/New%20Bucket/IMG_5338.jpg[/IMG] [IMG]http://i11.photobucket.com/albums/a166/ballsandy/New%20Bucket/IMG_5340.jpg[/IMG] At one point before I got the hint to just rotate the yokes 180 degrees I tried reversing the coils and in the process mixed the horizontal with the vertical coils. It was only a difference in 3 ohms but I don't think it liked that.

That looks like nightmare to fix. Can't you just solder on some resistor knobs on and calibrate?

I always wanted to grab one of those projection TVs for the projector. But apparently there's a gaint frensl lens on the front of them too! Cool. [video=youtube;XFw7U7V1Hok]http://www.youtube.com/watch?v=XFw7U7V1Hok[/video] Also, the 24V scooter I was running at 42V doesn't appreciate 63V. It starts to smoke a lil...

[QUOTE=Fourier;50737742]That looks like nightmare to fix. Can't you just solder on some resistor knobs on and calibrate?[/QUOTE] The adjustments already exist in the form of a board that basically gives feedback to the deflection amplifiers. It's got some two dozen assorted adjustments varying from linearity to trapezoid however none of them let you adjust when the picture is that badly distorted, hence my suspicion at least one of the amplifiers are blown.

So here's a small update on my fan project. The PWM controller I ordered has arrived and is wired up already: [T]https://f.lewd.se/wGfT6r_DSC_0202.JPG[/T][T]https://f.lewd.se/OpIhGj_DSC_0203.JPG[/T] I already tested it with the original motor and it works flawlessly. Right now I'm in the works with ordering two new motors, as I'm also going to make the same changes for my brother, who's got the same fan. The original motor was smelling funny and when I took it for a test spin it was ridiculously hot, plus the bearings are starting to fail. Another thing on my list is extending the housing, which I had the idea of doing by using a few spacers between the bolts. A fellow FPer has declared me insane however for spending the effort and cash on it, but hey it can't hurt to have a portable, controllable windstorm, right?

Can somebody please help me with the radio kit I built? Everything works apart for it needing tuning except it's barely audible unless I touch the coil marked "am" (top right of the schematic) or other components around it on the board. Then it goes to normal volume. This only happens when I touch one side of the coil. [IMG]https://www.staff.science.uu.nl/~tel00101/FotoAlbum/RadioCorner/Fotos4/GPaeSch.jpg[/IMG]

Almost sounds like a loose connection or bad winding on the AM inductor. Do a continuity check of both the AM coil (before/after touching) and check its connections to the surrounding components.

I wish there was a thanks rating. I'll try that shortly.

[QUOTE=Leestons;50796922]I wish there was a thanks rating.[/QUOTE] [IMG]https://facepunch.com/fp/ratings/wrench.png[/IMG]

[QUOTE=LoneWolf_Recon;50796903]Almost sounds like a loose connection or bad winding on the AM inductor. Do a continuity check of both the AM coil (before/after touching) and check its connections to the surrounding components.[/QUOTE] You beautiful bastard! It worked! Poor solder joint on one of the connections I think. Just need to tune it now I think . Only the FM side works but who listens to AM anyway? And for some reason the switch for them is backwards but oh well .

@ Pentium - I too, now have a projection screen TV that I found on the side of the road. It was even in my own neighborhood, so I didn't have to pick it up. I just used my truck to push it all the way to my garage, luckily it had little casters. [T]http://i.imgur.com/fKhlbzj.webp[/t] [T]http://i.imgur.com/Ex9dGqe.jpg[/t] Also. That child's scooter is a bit difficult to control. I had put 3 drill batteries ( 63V ) into it. It goes pretty fast. Unfortunately though because of the binary throttle ( no throttle or full throttle ), I failed to properly accelerate into my turn and fell off. So this was the result: [T]http://i.imgur.com/ki2silg.jpg[/t] The thing sounds like death. Guess that's what happens when you put 63V into a 24V brushed DC PM motor.

Whoever decided to use roman numerals for LTspice versions needs to be shot, version XVII is now out with a few good improvements (where the other 13 versions went I don't know).

[QUOTE=gjsdeath;50801055]@ Pentium - I too, now have a projection screen TV that I found on the side of the road. It was even in my own neighborhood, so I didn't have to pick it up. I just used my truck to push it all the way to my garage, luckily it had little casters. Also. That child's scooter is a bit difficult to control. I had put 3 drill batteries ( 63V ) into it. It goes pretty fast. Unfortunately though because of the binary throttle ( no throttle or full throttle ), I failed to properly accelerate into my turn and fell off. So this was the result: The thing sounds like death. Guess that's what happens when you put 63V into a 24V brushed DC PM motor.[/QUOTE] Oh those little cars can even have pep on 24V. They moved my 300 LB ass around, and right onto my ass. I want to get one and stick a real throttle on it. Then see what happens xD

[QUOTE=gjsdeath;50801055]Also. That child's scooter is a bit difficult to control. I had put 3 drill batteries ( 63V ) into it. It goes pretty fast. Unfortunately though because of the binary throttle ( no throttle or full throttle ), I failed to properly accelerate into my turn and fell off. So this was the result: [T]http://i.imgur.com/ki2silg.jpg[/t] The thing sounds like death. Guess that's what happens when you put 63V into a 24V brushed DC PM motor.[/QUOTE] You'd have to fashion some sort of high-current PWM controller, preferably one that also takes motor current into consideration so it can cut off power when the motor is overloaded.

I was working on an electric bicycle project a while back: [video]http://youtube.com/watch?v=O9olOVtUihw[/video] I even have the stuff to give it a real throttle. I just was riding on it cause I was bored. I don't really care to put much time into this scooter, since I don't even fit on it. It's dangerous as fuck. Plus the wimpy motor in it is nothing and will likely burn out after 5 mins of continuous riding at 63V. I might finish the bike project one day. I have a 130VDC 18A 2.65HP 6700RPM PM motor that I planed on using, found it in a treadmill. Those things have bad ass treadmill motors. I also have about 70 or so li-ion 18650 cells recovered from various laptops and electronics. But i haven't had much desire to finish it since I plan on getting a motorcycle instead. I could use my time on other, more useful projects.

[QUOTE=gjsdeath;50802442]I was working on an electric bicycle project a while back: [video]http://youtube.com/watch?v=O9olOVtUihw[/video] [/QUOTE] Sorry for asking, but how do you control the speed of the motor with the arduino? Like, what component is controlling the amount of power going into the motor? It might be a stupid question, but I also don't have the best knowledge about things. Thank you :smile:

[QUOTE=Kevin;50806709]Sorry for asking, but how do you control the speed of the motor with the arduino? Like, what component is controlling the amount of power going into the motor? It might be a stupid question, but I also don't have the best knowledge about things. Thank you :smile:[/QUOTE] It's not really changing the amount of power going into the motor, it is changing how often. Or how much power over time. Look up PWM (Pulse Width Modulation).

[QUOTE=Kevin;50806709]Sorry for asking, but how do you control the speed of the motor with the arduino? Like, what component is controlling the amount of power going into the motor? It might be a stupid question, but I also don't have the best knowledge about things. Thank you :smile:[/QUOTE] In that video I was using an N channel MOSFET to drive the motor. Similar to this diagram I just Googled: [t]http://bildr.org/blog/wp-content/uploads/2012/03/rfp30n06le-arduino-motor.png[/t]

You might be better getting a real controller also. It would be a tad bit better. I have heard some good on this [url]https://www.canakit.com/50a-dc-pwm-motor-speed-controller.html[/url]

Just browsing the arduino subforum of reddit and came across this piece of work: [thumb]http://i.imgur.com/iu2bRVp.jpg[/thumb]

Do you have a link?

[QUOTE=Leestons;50809618]Do you have a link?[/QUOTE] [url]https://www.reddit.com/r/arduino/comments/4lsoyn/my_first_attempt_at_soldering_can_someone_tell_me/[/url]