I’ve decided to start a new Youtube channel simply because I feel as though adding my projects and the things that I like to a video channel will drive me in ways I hadn’t had before. Thus far, I have 0 subscribers (aside from myself) and I’m genuinely curious to see how well I can make a Youtube channel work out. I believe I have some interesting things to share and some boring but popular things to share as well and a new Youtube channel that explores all those things.
Not the most graceful URL but I will get a better one once I get some subscribers and I’ve been around for a while. I will explore things that I do such as electronics, gaming, machining, photography and whatever else I come across.
Here’s a video detailing something mundane, my calculator collection.
So, feel free to look at my channel, subscribe and like a video or two. 🙂
I need to start my new project with my digital RTJ gage and in order to do so I need to use the quadrature decoder chip LS7166. I could use the actual encoder I’m going to use for the project but it is large and unwieldy so I decided to build a generator for it.
The concept is simple, have a knob that produces no waveform in the middle of it’s stroke and as the pot deviates from the center, the speed of the signal increases also changing direction based on which side the knob id turned to. I couldn’t use a PIC10F200 much to my chagrin because it doesn’t have an ADC module built in, the PIC10F222 does however. It still works within my concept of low-end mcu’s doing valuable jobs since they’re still only 55 cents in quantity, from digikey of all places.
Overall, it’s a pretty simple design.
GP3 -> unconnected
GP2 -> Channel B out (Digital output)
GP1 -> Channel A out (Digital output)
GP0 -> 10k Potentiometer in (Analog in)
Dead simple. I did program a bit of a dead spot in the middle so that one can stop the quadrature from advancing quite easily. I put 2 LEDs on it to indicate that it is in fact working. Anyways, here’s the source (again it’s in Oshonsoft BASIC)
I didn’t bother drawing up a circuit diagram since it’s such an easy circuit but here’s an additional image if you’re really curious. keep in mind that the board I’m using is Stripboard (aka Veroboard) so the traces run along one direction
Now for the fun challenge of making a simple serial interface MCU to the LS7166.
Now, for those of you who don’t know me, I’m a total cheapskate. I hate paying good money for good things and wind up buying lots of crap for lots of money. Over the years I’ve seen the question asked by fledgling electronics buffs ,”What should I get to outfit my lab?”
Now this innocuous question is usually asked by people who either don’t have money or are cheapskates like me. I have purchased all kinds of cheap and slightly-less-cheap stuff from a variety of sources over the years and I’ve seen the quality and lack thereof. I’ve worked with it and I’ve had my problems with it. What I figure might be informative is a general guideline of some things I’ve bought over the years, especially the cheap shit, also my opinions on this stuff for people who are starting out.
It should be stated that I’m no expert on electronics and perhaps that makes my opinion suitable for the new hobbyist like myself. Sometimes acceptable is good enough.
Every hobbyist needs a multimeter. They tell you voltages, resistances, current and often times things like frequency, diode voltage drop, continuity and various other things. This will be your most important tool when things don’t work as they should or when building a circuit.
Above is the cheap chinese multimeter. They come in various colors and designs and you can pick them up sometimes for $5. While they seem like a good deal, they are not. I have had a great many of these and they have all been a problem in one way or another. Either the voltage shown is wrong, or the fuse inside is pre-blown or sometimes certain functions simply don’t work. If you just want one around your house to check to see if something is live, buy one but otherwise I would stay away. Now for the hobbyist, there is the middle of the road multimeter, these are the ones I would get if you want a blend of quality and cost effectiveness. Some brands to consider are :
Agilent ($99 to $150)
Extech ($50 to $100)
Uni-T ($35-$100) meh..
There are others but those are the ones I have experience with. Obviously the more money you spend, typically the better product you’re going to get. If you’re gonna cheap out on anything in your lab, don’t cheap out on your multimeter, it is the single most important tool in your lab. Remember to get one that’s auto-ranging and don’t bother with ones that aren’t auto ranging or have those transistor testers on them. Transistor testers are the mark of a shitty multimeter.
The Power Supply
Whenever you do electronics work you need some source of power. This can range from using the USB port on your computer (like with an Arduino) to getting fully programmable supplies.
Some people try to save a few bucks and use a computer power supply for their projects. This isn’t bad since it outputs a whole lot of different voltages (3.3v, 5v, 12v, -12v) and can usually supply a whole lot of current. Only problem I have with them is the fact that they don’t tell you much about how much juice you’re using and you can’t limit the current.
Some people are really cheap and use wall-warts (like I did) for power. This is almost universally a bad idea because wall warts can fail spectacularly when shorted out or exposed to weird power loads. If you value your time and parts, don’t experiment this way.
The best way that’s cheap is simply an analog adjustable power supply. They go for about 110 to 140 bucks and will last you a long time under normal use. You can adjust both maximum voltage AND maximum current so you can perform various tasks with it and save yourself headaches sometimes by limiting current. Trust me on this, for most things this is the best option.
Everyone wants to be able to diagnose problems with their circuits, see if there is actually changes going on over data lines, or see if there’s noise on your power supply or something. Also it just looks cool to have a 50’s mad scientist’s lab for when people come over.
This is one item that I see people cheaping out on all the time, and frankly myself as well. While I don’t have top end equipment at the moment, I have second hand equipment that is pretty good.
Above is your general, all purpose analog scope. For most things this guy will serve you well. Buying a new one is often almost as expensive as buying a digital storage scope so buying one like this should be second hand. You can get an analog scope for a song on EBay sometimes and even around town at universities and college, they have extras kicking around. Using an analog scope correctly is a good skill to have and will serve you well with your digital storage scope, if you decide to get one.
These may be your ticket to have in your lab. Some companies like tequipment sell GW Instek oscilloscopes for $300 or so. While it can be a bit of an investment, this may be your ticket to having decent equipment for your hobbyist lair. The one shown above is obviously an older one and similar to my tektronix 100mhz scope. I got mine second hand for $400 and it’s been a great investment. To be fair, there are other economy brands such as OWON, Rigol and others but I only have experience with the instek ones.
The DSO Nano. They are cheap and tempting but they are not worth the money. From what I can tell, they have very low bandwidth and aren’t that great. There is a new model out for about 180 bucks, I may buy one to see what it’s all about. There are other portable DSOs out there but anything that’s any good is a fair amount of money such as the Fluke 123 and various others. OWON makes one for about $500 I believe.
Well, some people like Dave from EEVBlog warn people away from these USB oscilloscopes but I wonder why sometimes. The only difference really is that the display is now standard hardware instead of the company having to engineer a whole interface on custom hardware. It should be noted though to stay away from the cheap ones on EBay. The ones for about 60 bucks have a bandwidth in the low KHz, yes, not MHz and they suck. Stay away from cheap USB oscilloscopes. somebody who appears to make good ones is Picotech, but that said they are the only company I have experience in that regard.
Anyways, You can get away with $300 oscilloscopes for hobby work, don’t cheap out if you can help it. It’ll make your life easier.
Well, I don’t know if I can say “The rest”. there are so many things you can buy to accompany your lab that it’d take many tens of pages of writing to cover even in a very cursory fashion.
I’ll list a few things in point form you could need in your lab to make it both workable and useful.
Breadboards – Cheap and effective, get at least 2. You can get them for 5 bucks each on EBay
Soldering iron – Spend 100 dollars and get a temperature controlled one. Weller or Hakko. Those cheap 20 watt soldering irons suck and you’ll waste more time than anything with them.
Side nips, you can get these for like 3 dollars.
Wire strippers – Again, EBay, Cheap. Get the lower gage ones 20-30 gage unless you do a lot of speaker wire and power stuff.
Wire – get some rolls of solid core wire in both 22 and 24 gage. get different colors. red, black, green and white are recommended. more colors the better.
Resistors – you can get sets of resistors off EBay or from Jameco for cheap. Get 1/4 watt ones, that’s standard.
Diodes – a pack of diodes off ebay might cost you upwards of 2 dollars. yes. cheap
component packs – These carry a whole slew of random parts you might need. Everything from switches and caps to potentiometers and other goodies.
Alligator Clips – Get some alligator clip wires, very handy for everything.
A good light – Get yourself some adequate lighting, only costs a few bucks but makes working much more pleasant.
Arduino – Personally, I hate arduinos but if you’re new to things, get one. It introduces things in a much more pleasant way and allows results quicker.
The DON’T List
Don’t get random resistors in a bag, waste of time and money. the standard set is fine
Don’t get bags of transistors, you’ll never use them. You’ll never really know what they are. You’ll never really know if they’re any good.
Don’t get IC grab bags. You will very rarely get anything good. Trust me, I’ve bought them before.
Don’t buy Stick Irons for soldering, they suck!
Anyways, that’s what I have to say. I’m sure I’ll get comments telling me how painfully incorrect I am and that I’m a subhuman monster for saying such things. If I’m terribly wrong, tell me, perhaps I’ll change it.
It should be said that I started out with damn near nothing but a bench and a $10 multimeter. I struggled and struggled and bought nothing but cheap crap because I’m a cheapskate. I didn’t buy a compiler and there was no such thing as an Arduino (At least not to my knowledge) so I wrote all my programs in assembly which is extremely time consuming.
Anyways, I suppose what I’m trying to say is that if I can learn it, anyone can. even on a limited budget. If you’re serious about it though, spend the extra few bucks and get something decent.
So a company that shares a parking lot with out company sells and distributes photocopier services. One day I was told about a whole bunch of photocopiers that were just sitting there. Deciding to take the plunge and rip through them the bounty was great!
There you go. 33 steppers from only 10 or so photocopiers. I found the following things.
brushless dc motors
all kinds of plastic gearing, great for all kinds of things
good limit switches
Everything an inventor could need. Amazing!
Well, tomorrow I got 15 more copiers to disassemble! Everyone should try disassembling them!
For anyone that needs the drawing for a 55g servo, here we go. It’s been some time since I’ve updated but never fear, more boring stuff is to be posted soon 🙂
heres is a link to the actual PDF if you want it! servo body.pdf
If anyone needs dimensions or drawings of the horns, I’ve got the 4 lobed horn drawn and the round one. I can’t guarantee that these drawings have no mistakes, i just quickly draw them. Hopefully they’re of use to some one though.
A bit ago I got the idea of trying to determine the mixture of coolant vs. water by detecting both light occlusion of the mixture and the wavelengths blocked / passed. This initial device is just a rough prototype that will assist me in determining a course of action in regards to overall design.
The idea behind the device is to have the sensor fitted on to any pipe attached to the machine where coolant goes through and give a live measurement of coolant mix and alert the operator if the mix gets too high or low. Also I’d like it to detect tramp oils that have been beaten in to the coolant.
The board itself is pretty simple, just a PIC16f690 hooked up to an rs232 driver and using three analog channels. I may in the future build a more sophisticated ADC board, but for now, this will do. The mcu is linked to the two rail to rail opamps, 7014D’s to be exact. they were needed to condition the signal from the LEDs.
The sensor area is basically a cup with a white LED as a light source for the sensor LEDs. The three LEDs are IR, Orange-red, and Green. The LED’s respond to wavelengths more energetic than the ones they emit, therefore, the selections I made. I did try a blue LED but the response wasn’t good at all. Hopefully it will provide useful data, hopefully.
In order to make data easier to collect, I put rs232 communications on it. I can store and track data this way. Above is some of the terminal output. Notice that I’m taking 10000 samples… this has the effect of increasing, to a very limited degree, the resolution of the device. It is however fraught with error thus far…
Anyways, any data collected and the design of this is extremely preliminary. I’m not even sure it’s a valid or useful idea yet.
As an extra bonus, or punishment, here’s a video I made for this device.
Well, it has been some time since I posted, about a month and a half or so. There have a been a number of events that have occurred in that time that have both beneficial yet disappointing. I’m not really sure where things are going right now but I hope they get better.
Anyways, on to some things I’ve been working on.
While I am a decent machinist, it is a job that I vowed to myself I would never do again. Lo and behold, I am machining again in order to get some funds and to simply make it through the months in terms of rent and bills. Some of my previous stuff has left me bone dry in terms of money. Realistically, I should thank my lucky stars that I have a skill I can fall back on that pays well and is relatively easy, most others are not so lucky.
Luckily, the shop I’m working at is pretty decent, though I’m not the machinist I once was and my machining style doesn’t really match the pace and style of the jobber shop I’m working at. Hopefully I either get better soon or find something more along the lines of what I’ve become good at.
Stamping machine with the Haas mill
This is a little project that I came up with after thinking about dot-peen machines. Basically the idea is to take a Haas mill and allow full control of its machinery to turn it in to a makeshift dot-peen marking machine.
This feat is accomplished through the serial port with a pass-through interpreter box connected to a computer.
Here is how it is all achieved.
First Step: Computer –
This is where the points and fonts are generated and created. All of the end points are sent out from the computer at a lower baud rate than the mill uses. This allows for longer cable length on the RS-232. Of course I could use USB or RS-485 but RS-232 is more common an interface. A sample output might be:
MOVE X.455 Y1. (Basically a rapid move)
STMP X.461 Y1. (Stamp here)
STMP X.467 Y1. (Stamp here)
HOME (Go back home)
The communication is full duplex between the pass-through and computer so that the pass-through can request more data.
Second Step: Pass Through –
Despite its name, it does not actually pass data through. It interprets the data and controls the stamping head. It will interpret the data and send the machine the appropriate G-codes to perform the commands. The pass through will communicate with the machine at 115200bps whereas the computer <-> passthrough is about 9600bps. a sample output might look like this (based on the above text):
G00 X.455 Y1.;
G01 X.461 Y1. F200.; (move to stamp position)
DPRNT [S]; (Is at position, passthrough will stamp)
G01 X.467 Y1. F200.; (move to stamp position)
DPRNT [S]; (Is at position, passthrough will stamp)
G28 G91 Z0;
G28 G91 Y0;
Third Step: Stamping head –
Not really a step so much as device to peen the surface of the part. Here is a picture of an earlier design I made for a stamping head.
I don’t know if I’ll ever do this one. Macros need to be enabled in order for this to work so a lot of machines won’t be able to take advantage of it. Also, my time is limited.
Programming a CAM system
Since the shop I’m at has no CAM system for the guys on the floor and I don’t want to use a cracked copy of say, Gibbs or MasterCAM. I’m writing my own. The going is slow but I am slowly developing a little 2.5D cam system. The math function are working and the object creation is starting to come on line. Now for an interface. I am thinking of migrating over the VB.NET for this program since it does have a lot of nice object handling functions and it is a little easier than creating a user interface from scratch.
Anyways, That’s what I’ve been up to for the last while. Hopefully I get a car soon so that I don’t have to walk in this anymore. 🙂
Well, this has a been a long few days of work. I have created the ideal rotary viscometer in both terms of price and repeatability. Now, this idea is nothing new but I’m simply happy that it works. I guess it’d be prudent to go in to how it works…
How it works:
The concept is simple. you have a shaft that is separated by a spring, in this case two plastic cups connected by a ball bearing with rods sticking out one side. This shaft is driven by a small gear motor and a set of paddles is attached to the other end. While this is rotating, the difference in the driven and the resisted side is measured with some form of instrument be it a hall effect sensor or a slot type optical transducer.
What I used:
Well, as far as materials are concerned, for the prototype I used blocks of polyethylene to support both the motor and the shafts. The material has pretty low friction properties at low loads and thus I used it as the bearing on the bottom. The actual difference mechanism is made from a high density plastic. I would probably use this material again as it’s light, rugged and easy to machine. For the real unit, I may still use this plastic as it is more than strong enough and it’s easy to machine.
As for the drive I used a design similar to the older designs with PWM motor output, serial output, keyboard input, LCD out and 2 channels of input. This is all controlled with a PIC18F2620 which is more than enough for it’s needs.
The motor itself is a Hsiang Neng gearmotor running at 12 volts. It’s a piece of shit but that’s not important at this stage of the game.
So, finally, a desired feature list:
1. RS-485 Out
2. KU and Cp out
3. Multi-fluid calibration, this feature allows the user to select fluids of any KU value and calibrate the unit by entering them in.
4. Easy to use menus. Too often have I seen automation stuff that’s unintuitive. This hould be easy for the operator to understand and easy for the people to use.
5. Speed selection, so that you can use under-powered motors.
Anyways, here’s a gallery of some of the pictures of what could be a DIY stormer viscometer.
Well, for the past little while, I’ve been working on a bizarre clock made with LEDs glued into a dollar-store cookie sheet. I got the idea just out of the blue and decided that it would be fun to build. Now, it’s nearing completion so I figured it’d be prudent to document the miserable contraption. I guess I should go through the steps it took to get this thing running.
First, I took one of those dollar store cookie sheets and drilled it through for 40 LEDs. 12 for the hours, 12 for the minutes, 5 for the seconds, 5 more for the div/5 minutes and five more for the outside and the PM light.
Drilling it wasn’t much fun but, when it was finished, I started to insert the LEDs with the grounds all towards the outside of their respective circle. Then I mixed up some epoxy and drizzled it over the backs of the LED’s. Unfortunately, the epoxy didn’t hold very well on the other epoxy surfaces so I used hot glue to tie them down.
As you can see, I labeled it in reverse of the other side so that I could get ‘er working. Thus started the long job of soldering the whole thing.
The image show isn’t the complete one, but it took me several hours to solder it all together. I used 7 groups of 6 LEDs in order to display the image. In this case I used the 7 groups for the duty cycle, thus a 1/7 duty cycle was used. Each of the 7 groups is fed ground through an MPSA13 Darlington transistor. Here’s a picture of the board that controls it.
Pretty fucking ugly, I know. But it works and I used an MCU (PIC18F4685) that was a little overkill but that’s fine, I’ve got quite a few of those. Anyways, so far so good, though it seems a little impractical as a clock and I think I set the rings of the minutes and hours too close together. Oh well.
It hasn’t been long since my last update about this thing but I’ve made some progress as far as making the unit into a single board. I simply used the AD7705B as I suspected it work work great for this application. I’ve been playing around with reducing the amount of noise coming from the sensor but random fields are causing the ad7705 to produce strange numbers, even when my hand just gets close to the unit. Here are some pictures of the unit.
Thus far it seems to work though, at least when tested with a multimeter. Sadly though, it seems impossible to test it with the oscilloscope because it uses the same ground as the power supply, damnit!