Old School Gaming PC

These days when you want to play a old game as in DOS compatible or Windows9x you have to emulate a system with DOSBox or VBox.
Well They work fine but some times you run into issues or it just doesn’t feel right.
So lets talk about building a bare metal old school gaming rig.

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Quick safety tips

When dealing with electronics or anything really you need to know safety is key. So here are a few tips most people don’t know or don’t even think about.

ONE: Storing Capacitors.
Never store Electrolytic Capacitors in a plastic box. I haven’t had any issues with high rated uF caps but with high voltage low uF caps they have recharged enough to pop if shorted. Store them in a cardboard or anti-static bag. Or toss on a bleed resistor so if it tries to build a charge it will quickly discharge before a charge will build up. Reason why a charge builds up is due to static electricity and electronic noise. Granted plastic is a isolator but it can also hold a static charge on the surface.

TWO: Power extension cables.
We have all wrapped extension cables incorrectly. Such as holding a end of the cable then wrapping it around the elbow. This overtime hurts the cable and adds twists and eventually creates breaks in the wire. This could make a device that is plugged in to not work well and would hurt the device or even worse cause the extension cable to get too hot in a spot or two from too much current and melt away the sheathing. I had this happen to myself when I was running a circular saw for a whole day replacing siding on my mother’s old house. The cable was only a couple of years old and I was using it on almost a daily basis. The cable literately caught on fire about a foot from the male end of the cable. I then remembered how my father told me to store the extension cables. By then I couldn’t remember but I soon figured it out and been storing them as a daisy chain since. Here is a video I found on how to wrap cords in a daisy chain.

THREE: Mixing chemicals
Always read the ingredients or a datasheet. Last thing you want is to mix some chemicals and end up blowing yourself up let alone poisoning yourself or others. Reason why I stress this is at my job I kept watching people mix bleach in with the floor cleaner that has ammonia. When mixing those two together you create a chloramine vapor. When I took over on ordering supplies at work I stopped ordering bleach and when everyone complained I told everyone why, they either didn’t care because it made the floor cleaner or didn’t believe me. Also bleach and vinegar is just as bad. Basically any acidic solvents mixed with bleach is a bad thing.
Here is a short list on chemicals you should never mix.

Bleach and Ammonia = chloramine vapor
Bleach and Vinegar = Chlorine Gas
Bleach and Rubbing Alcohol = Toxic Chloroform
Vinegar and Peroxide = Paracetic Acid

Power Supply rebuild.

Well slapping together the power supply was a dumb idea. Some how I burnt up the opamp. I think it was a error on my part for not looking at the correct datasheet and pumped too much voltage into the differential input.

So instead of building my own I’m going to just copy some one else. However with a twist. Instead of using the same BOM I’m going to use a few different parts. The power supply will be heavily based off of Peter Oakes supply. I have watched all of his videos on build the supply. Instead of using a TLE2144 Opamp I will use a LM339N. Also I’ll be using a different Mosfet. Kinda wish I could use the same parts but im on a budget of zero dollars and can only use on what I have in my inventory.

Also instead of using the same transformer from the last supply I have a different one that will work better in the long run. After rectification it produces 25volts and can handle a couple of amps. Also if I wanted to I could easily add a second channel and it has enough multi-taps to power the quad opamp and a fan unlike the old one that I tossed in a small switched 12volt supply and added a voltage divider for the opamp.

Cheap R/C car modding

I use to play with R/C cars when I was younger. I often thought on how to make a little cheap car go faster with out dishing out a ton of money. Well it just hit me when I was working on the spindle control for the CNC.

A typical cheap RC car is nothing more then a RC receiver and one or two H bridges. If you toss on a higher voltage battery you’ll burn something up. Reason being the car would be designed to use enough power to run the radio and H bridge.

Now if we add a second H bridge we can add as much power as the drive train of the car can handle. Or even re-purpose the controller for something else.

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Just add the H bridge to the output of the controller and use a higher voltage for the input and Bob’s your uncle.

Electronic Dummy load

I finally got around to building an Electronic Dummy Load. I found a few schematics floating around the web and everyone keeps tossing a AVR into the mix. A simple analog device is perfect for testing a power supply. So I did a little research and came up with a nice small device. Since I attend to rip parts from CRT televisions I have a good stock pile of mosfets and power resistors. I’m using two 6.8ohm three watt resistors in parallel and a FQS9n90C TO-3P N-channel mosfet. A simple LM358 opamp to control things. For a power source im using a 7815 regulator and a typical wall wart for isolation. When I am finished with the build I will post the schematic and pictures.

Power supply update

Just so I can get work done I tossed together part of the power supply. The circuit is still put together on a small breadboard until I can make a PCB. For now I have a LM317 for current limiting and a simple LM358 opamp controlling the voltage kinda like a regulator. To dial in the voltage I have to use a multimeter as a visual aid.

Hopefully next week I can finish the darn thing and even add some LED/LCD panels.

Clothes dryer repair gone wrong

Not a DIY how to but more of what you’ll run into.

My “Fake Mother in-law” (Person that calls my wife her daughter) asked me to repair her clothes dryer since my wife gloated a couple of times fixing ours. I get there and sure enough the belt had snap. I attend to order my parts but she was in desperate need so I found a local repair shop that had the part in stock. I replaced it and the following day I got a call that it smelt like electrical burning. So yesterday I went over and sure enough the belt slipped/twisted and melted until it snapped. I went back down to the repair shop to get a new belt and the owner of the shop grilled me and said it was my fault. I bought a new belt and go a 40% off discount and installed the belt. I ran it for five minutes and noticed that a few issues.

The belt is super thin while the pulley to the idler and motor itself is three times the width. It’s a rib belt and only has three skinny ribs. Kinda felt like I was using a long rubber band.
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Here is a picture of the idler. It’s not even bolted down but uses a couple of flange flaps to hold i down. Not the best suite idea since you have a belt tightly pressing it back. The pulley to the motor is the same style. Now thinking back to my dryer repair it used a much wider belt and the pulley to the motor was deeper. While the dryer was running for five minutes you could clearly see the belt going back and forth. The parts guy even said the motor should have a plastic shroud so if the belt slips off it will go back into place but when I returned to the dryer there is no shroud in site. Even finding the exploded parts view of the dryer it does not list a shroud. In all the dryer itself is very poor construction. Even high end dryers such as Maytag are not very well put together. I have a Maytag and it is nothing more then a rebranded Whirlpool with a mixture of Whirlpool and Kenmoore parts.

I don’t know if it’s because I’m use to working on cars that a V-Belt style belt runs at high RPMs or no one really notices the poor construction of these dryers and when something breaks it will fall apart constantly. Guess I better count my blessings and be glad it wasn’t the washing machine.

A few tips however when working on one of these.

  1. Disconnect the Power.
  2. Have a bungie cord or rope handy to hold the lid open.
  3. Use nut driver screw drivers since the dryer is held together with self-tapping screws.
  4. Be prepared to get dirty.
  5. Grow a third arm.

It’s a pain in the rear but it is better then spending double the amount what you spent on the dryer new for a repair guy.

Technology for the simple minded

I have thought about this quite a bit and even talked it over with a few people and we all agreed that modern Technology has gone stupid. Mostly to protean the novice user into thinking they know all.

For a example a friend of a friend asked me about fixing a computer. She said she uses Xfinity and it said on her computer about a certificate was out of date. I asked what version of windows and she said Xfinity. From there I couldn’t go further or else I would of laughed my butt off and maybe pass out from the lack of air. Now this doesn’t mean she is the only person in the world. I have met novice users that think their ISP had to fix their PC or some one hacked their PC when they in fact hit a wrong key. Now even end users have gone stupid with things such as “The internet of things” and the cloud.

IoTs has been around since the internet. It’s not a new thing but lately it has became a trend and I have seen some stupid things labeled with it like people connecting to a RC car and drive around some stranger’s house. Or read Radiation levels near some house that is no where near anything radioactive.

Cloud Computing is another dumb thing in the world of Computing. It’s nothing more then a public VPN and is still vulnerable to attacks. Also it has a couple of backlashes. When I hear the term “100% secure” and “Unhackable” in all reality it isn’t. It’s just propaganda of a company trying to sell their product. You can be protected on a hardware and software level but still not be 100% secured or unhackable. Reason being is simple, human interaction. As a typical person you will slip up and leave a clue or even put out a welcome mat. When you get down to it, it’s just Social Engineering that will bite you in the rear. People attend not to follow the rules aswell. For a example back in the 90s with AOL. Every chat window you would open there would be a disclaimer stating “No one from AOL will ask you for billing information” or something like that. Yet people were dumb enough to still send their billing information to the person that sent that message.

Since more and more people are now on social media let alone using the web everyone falls for fake stories and Ads have gotten smarter/stronger. For a example tons of people really thought McDonald’s was going to get rid of the BigMac because some prankster posted it on social media. Even FoxNews thought it was true. I’ve noticed my local News channels are starting to post fake stories that have been going around social media such as a 94 year old woman dying from falling asleep with a vibrator that ended electrocuted her. Typical people “Sharing” slide shows that are riddled with Ads. Nine times out of ten they’re about a fake topic or just something stupid. It is just there for some company to get paid in hopes some one will click on a Ad.

Microsoft in my opinion has even taken on the dumb and weak with Windows 10. It is riddled in Ads and bloat-ware. I tried it for ten minutes and thought to myself I rather deal with Windows ME and Vista then this. I already told myself when Windows 7 becomes obsolete I’ll install Linux on the family PC.

HDPE revisted

This Tuesday I need to mold some parts for the CNC. Mostly bushings and a holder for the spindle. I am currently using some cheap round nylon bushing that attend to hang even when lubed. So stay tuned for some pictures of the progress.

CNC Progress (With pics)

Yesterday I started on the CNC X axis. I decided to go with a smaller unit and instead of a moving gantry I went with a moving sled. It’s made out of acrylic and stainless hardware.

When working with scrap acrylic you really don’t want to scratch it up let alone you need something on it to draw your measurements.

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When you want to cut it in half the easiest way is to measure corner to corner and where the two lines intersect is the center. A square is best to make sure everything is evenly square.

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I bought a “Mighty Saw” from Harbor freight a while back. Have to saw it works great for small pieces of acrylic. I added a extension to the miter gauge’s handle since the little nub of a handle was a joke.

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I ripped the plate down and later decided to just work on the X axis.

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The bigger sheet for the bottom of the CNC came from a old 17inch LCD. I was able to use butt joints for the hardware. The two bigger holes are for th slide rails. I plan to make this some what modular so if I wanted a bigger bed I can just swap the slide rails over.

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A test fit for one of the slide rails. To make life easier I used some plastic bushings. Maybe down the road I’ll switch to linear bearings.

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X axis stepper installed.

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This is a old hard drive head bearing. Works just fine for the belt.

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Here I am trying t figure out how to mount the bed.

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Since I was running out of time to finish it yesterday I stopped and waited for today.

Today I added some feet to the bottom and even added thumb screws to level out the unit. I also mounted the bed and slapped on a belt that is a bit on the loose side but works for a simple test. I really need to add some limit switches as well. Here is a short demo video of it in action.