A Maker’s Microwave

How many microwaves have you thrown out because they get flaky after a few months? The thrift stores are full of these rejects. How many times have you wondered who designed the user interface for these things? What planet were they from? Wouldn’t it be nice to have a microwave that isn’t flaky and has a sensible interface?

Nathan did exactly that. He took a broken microwave and put in his own smarts via a Raspberry PI. It has a beautiful control panel, accepts voice commands and provides voice synthesized feedback. It even scans a product bar code to fetch cooking instructions. It is so smart, that you don’t have to babysit the thing to stop it to stir. With the bar code powered instructions, it will stop at the right time, tell you to stir, and start up again to finish the cooking. He even did a tablet interface.

The key to a project like this is a microwave with an intact magnetron, which is the tube which does the cooking. As already mentioned, most of the time these tubes are fine. It is the sorry electronics that flake out. Take inspiration from this guy. You don’t have to go as hog wild as he did, but you can rescue your own microwave (or one from the thrift store) by adding a little bit of your own electronics. Customize to do what you want it to do, and you’ll likely have a microwave for life, suited exactly to your needs.

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Get Accredited Degree Online

While many universities have been offering some of their courses online for a few years now, none have offered actual degrees (aside from dubious “professional” colleges). Georgia Tech is first to have taken the leap. In collaboration with Udacity (which I have written about before), they are offering an accredited masters of computer science degree for $7,000.

Of particular interest is the fact that the actual courses are free. It is only the degree that costs money. This is nevertheless good news. There are a number of positive things to note:

  • An actual college degree can be obtained online from home without having to move and live near or on a campus.
  • The cost is much less than tuition for the same degree is normally; not to mention the considerable savings in living expenses.
  • The actual education is free for everyone in the world.
  • The degree is obtained via proctored exams offered at 4000 Pearson locations around the country.

That last item also points to another positive trend – certification by exam. Currently, the primary value of a college degree has nothing to do with education. Its main value is the piece of paper that opens doors into the world of employment. Sadly, most employers don’t care about what you know, but only that you have a piece of paper that claims you know it.

The tide supporting that practice is beginning to ebb. In the computer world, certification by exam is becoming more and more mainstream. With this major change from Georgia Tech, that trend will become even more mainstream and potentially lead to the same practice in other disciplines.

With college education, similarly with health care, increasingly showing itself to be little more than lot of money for little real value, this news is most welcome.

 

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Nanotechnology at Work – A Wonder Waterproof Coating Now Available

There is a new two-part coating that will make anything waterproof. Called Ultra-Ever Dry, it is nano-technology based and works wonders. Watch the video below and be amazed:

The only problem with this product is it is far too expensive to be practical and only comes in large industrial quantities.

There is now good news. Rust-oleum has brought out a similar product called NeverWet. You can buy it at Home Depot for only $20 for 18 oz. It is still pricey, but practical for many things. Imagine boots that cannot get wet or even muddy. This product is definitely not your father’s Scotch-guard. I just hope there isn’t a patent war, putting this technology out of reach for us regular folks.

For more materials that have great uses for the maker, see Materials for the Maker/Provider.

If you use this product, please share the applications you find for it in the comments.

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Why You Should Homeschool Your Child

Here at ProvideYourOwn, we believe one of the most important things you can do for yourself and your children is to teach them at home. If you need yet another reason to do so, take a moment to watch this telling interview with Michio Kaku on how children’s intellect and desire to learn are crushed by the schools:

Of course, homeschooling is not a panacea if it duplicates the public school model. Set your child free – let him or her direct their own learning. That is what children are designed to do, and it makes your job as a mom or dad that much easier.

Thanks to PCBHeaven for the link.

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Making Hay

We just finished making this year’s hay at our family farm.

Haymaking is an art….. It is exhausting….. It is glorious.

It is worthwhile to experience it at least once. You might even want to add it to your bucket list. For city folks, you may be wondering what is this big deal about hay? Hay is like the stuff we find in small bales in October right?

Like most things in life, there is a lot more to hay than first realized. When you are done reading this article, you will have incorporated some key knowledge of country living and keeping animals. It is hoped you will be able to vicariously enjoy the process to some extent as well.

What is Hay?

Hay is dried grass or possibly other green plants. It is not straw. While straw is a dried plant, it is made from the stems of cereal grasses such as wheat or oats after the grain has been harvested. By harvest-time, the stems are turning brown and have almost zero nutritional value. Straw is good for bedding animals. It is worthless for food.

Grass on the other hand is excellent food for grazing animals. It is even appreciated by pigs, chickens and many other animals. Even my children like to eat it on occasion (I know that sounds strange, but then children raised on a diverse farm can be rather strange to some people, including their parents).

In the spring, grass often grows faster than the animals can eat it. When that happens, it can be mechanically harvested, sun-dried and stored for later consumption such as the wintertime or periods of drought.

What is Good Hay?

If one is to make or use hay, one needs to know what good hay is like. I remember going to an Ag field day with some of my children and participating in a hay judging contest. The judges were county Ag agents armed with a sophisticated sensor and lab analysis. The participants had to use their eyes and their noses. My children also used their taste buds – surely the ultimate test!

Good hay should smell good. It should be a pale green color, and have that wonderful smell of freshly dried hay. There should be no mold. Mold grows when the hay is not dry enough when it is put up. Hay is brown if it sat in the sun too long before raking. If the hay is made from grass that is too mature or has been rained on after cutting, it won’t be as sweet smelling (or tasting for those who care to).

So how did we do in the hay judging contest? We came in at the top, but I owe much of it to my children who shared with me how the better bales tasted.

Making Hay is an Art

The art of haymaking is something that must be experienced to be fully appreciated. Hay can come in a wide variety of quality. You would think that drying grass would be pretty simple. It probably is if you just took a handful and put it in the microwave. Try cutting acres of it to dry naturally in the sun… without getting rained on… or too bleached in the sun.

Timing is also critical. Kind of like straw, if the grass goes to seed for too long before cutting, the quality is diminished. Here are some of the more critical factors.

The Right Climate Helps

In many locations, it can be very difficult to make hay. Not only difficult, but impossible to make very good hay. The sun is hard on hay. Rain is even harder. The best hay is made where the humidity is low and rain infrequent. That way the hay dries faster than the sun can bleach it out. It also doesn’t get rained on.

The Weather Must be Just Right

Rain will ruin hay. For some reason, once the hay is dry, if it gets rained on and then dried a second time, it is not very good. It would work for bedding however. Hay can take a light rain when it is first cut however.

Here in Kentucky, we have a mini-monsoon season in April and May, followed by cycles of sun with afternoon showers. April showers bring May flowers, and it also brings on the hay. The hay is often ready to be cut before the showers end. As June draws nigh, the periods of sun between showers grow longer, but the grass becomes poorer.

Timing is Everything

The trick is to spring into action at the start of the right cycle. A wrong guess can mean ruined hay. Waiting too long for the best weather window will mean poorer quality hay. Since a little rain right after cutting is okay, sometimes it pays to cut when there is a chance of rain, but when there is a promise of clear weather later on.

It takes years of weather watching during hay season in a given area before one can become proficient in the art of timing. Alternatively, one can simply drive around and spy on the neighbors. Start cutting when they start cutting. Which brings up the next requirement for haymaking.

It Takes Equipment

Hay doesn’t make itself. Unless an animal cuts the grass in the process of eating it, it take a piece of equipment to do so. And not just for cutting either. Hay must be cut, tedded (optionally), raked, baled (optionally) and protected against the weather. All of these things require special equipment.

Mowing

Mowing is the most labor intensive part of the process. You can’t use a rotary cutter like your lawnmower, because it chops the grass too fine. The grass must be cut at the base and left on the ground in its full length. Why? Because you need that length in order to rake and transport it. Short grass just won’t work for the next steps.

In the old days, a scythe was used. It took a stout man a whole day (12 hours) to mow one acre. You can still mow that way today. The trick to using a scythe is to use the Austrian kind, not the American kind. You can buy lightweight aluminum ones today. With the Austrian kind you don’t have to bend over to cut. You stand upright and sweep in a circular motion. It is actually very pleasant work and poets have waxed eloquently about it.

For anything over 1/4 acre, the Sickle-Bar Mower is a better tool. Pa in Laura Ingall’s The Long Winter used a horse drawn sickle bar mower to cut his hay. You can still find these mowers as well as buy small two-wheel tractor versions (including old Gravely’s) or put a big one on a tractor. They are fairly cheap when purchased used, and don’t need a very big tractor.

For good haymaking, a simple Sickle Mower doesn’t do nearly as good of a job as the more modern mowers. Modern tractor-drawn mowers crimp the grass between rollers as it mows. This action squeezes most of the water out, making the hay dry faster with less bleaching. The downside is they are very expensive. Unless one cuts hay professionally or has over 100 acres to cut, they are too pricey to justify.

Tedding

Tedding is an optional step before raking. When you ted, you basically scatter the mowed hay over the ground. The reason is the get rid of big clumps and turn the hay for more even drying. Without tedding, the hay on top gets bleached while the hay underneath is still moist. Tedding will even out the drying more.

Tedding by hand is way to much work to even consider. I do however, break up any large piles I leave in the process of mowing. Tractor drawn tedders are nice, but they are rather expensive. Most farmers don’t bother.

Raking

Raking is the next step in haymaking. When the hay is cut it lies like a blanket on the ground. Raking it is the process of gathering it into windrows. A windrow is a low mound of grass that forms a row along the ground. It helps finish the drying and makes it easier to gather for storage.

Raking by hand is almost as labor intensive as mowing by hand – about half an acre is tops. Fortunately, ‘side delivery’ rakes are fairly inexpensive. You can get horse drawn ones as well as tractor drawn versions. You don’t even need a tractor to pull them either.

For many years, I would pull ours behind this old jeep we owned. One thing to watch out for when using cars and trucks for this work – the grass can easily get wrapped around the drive shaft and then catch fire! That happened to us when we had pulled a wagon load of hay into the barn. Thankfully, a quick acting young man was able to save the day without damage to either car or barn.

Putting It Up

In the olden days before hay balers, hay was loaded by pitchfork into wagons and then either piled into humongous barns or else onto even more humongous stacks. I have always wanted to make a haystack, but the art of that is quite a feat – one that I have never mastered. My Dad told me about making haystacks around a pole 20 feet in the air! I am not certain about the 20′ length, but I remember it was really tall.

Loose hay can be very high quality. Since it is not tightly baled, it has more time to dry fully. It can also be put up somewhat wet and still dry. Gene Logsdon swears by it. For many years, we put our hay up loose by hand. It takes a good wagon, a few hay rakes (although steel tine rakes work as well), several lightweight pitchforks (which aren’t made anymore) and a lot of hands – more on that in a bit.

Nowadays, most people bale their hay – either in rectangular bales (called square bales) or large round bales. When baled in the round, the process is called ‘rolling hay’. Square bales are heavy – over 50 pounds and must be picked up and stacked by hand. This type of hay is considered the best, but takes a lot of labor and a good barn to put it in.

Round bales are the most popular because they are like mini-haystacks, which is to say they can be left outside all year. Weighing over 1000 pounds, they are easily handled by tractor, making for less labor. With the low labor requirements and simpler storage options, you can see why these types of bales are so popular.

It Takes Work

Haymaking is hard work. It is also magnificent work. I would not say it is pleasant, but it is rewarding. Mowing is fun – whether by hand, horse or tractor.

Raking is extremely satisfying. I rank it up there along with watching a dog chew a bone or a cow eating grass. Seeing the grass roll out the side of the rake is kind of like watching the ocean water rolling into the beach.

Putting the hay up is where the rubber meets the road. Doing it loose is the hardest labor you will ever do, along with the longest day you have ever had. Square baling is not much different – you just put up more hay. The amount of work is the same, but a lot heavier.

Round baling is a bit different. It takes much less labor, but once it is done, the bales still must be moved – either into rows at the edge of the field or into hay sheds. This step must be done by a tractor – one or at most two bales at a time. That’s a lot of tedious moving of hay. Nobody likes doing it.

The Secret Concoction Every Haymaker Needs

When doing any kind of haymaking, the weather is hot and the work is exhausting. Unlike many other types of work, it can’t be left for another day when you get tired. The rain won’t hold off forever. In fact, the storm clouds are usually rolling in while the hay is being put up.

How does one keep going when completely exhausted? Ahh, there is fortunately for us haymakers a secret potion exists – eggnog. Eggnog you say? That beverage they sell at Christmastime? Drink it in June?

Yes. To say it is refreshing is like saying the sun is bright. My highest praise to Laura Ingalls for sharing this wonderful secret in her books. When her Pa was making hay, at just the right time, Ma would send out a pitcher of this delightful beverage to Pa and Laura as they put up their hay.

I can personally attest to its effectiveness, and furthermore, I swear by it. You can be completely spent, exhausted, and too pooped to continue anymore. Then, drink a few glasses of eggnog and as if by magic – your nearly dead body revives and you find the strength to carry on until the job is done.

But they don’t sell eggnog in June? That is not a problem. You don’t want that fake stuff anyway. The real stuff is easily made. The ingredients are just milk, raw eggs, sugar, and vanilla. Of course you want eggs from hens that eat grass. They are not only more nutritious, but you avoid Salmonella which is ubiquitous in factor produced eggs, even organic ones. If you can get raw milk, that is also a plus.

Conclusion

Hopefully, you now have a good taste of what it takes to make good hay. Of course, you can’t appreciate the experience until you do it yourself.

As I have said before, making hay is a glorious experience. There is nothing else like it. The sun is warm and pleasant, the smell of hay is wonderful and the work can be immensely rewarding as well. If you put your hay up loose or in square bales – the teamwork is far more rewarding than any organized sport. If you do it with strangers, you will have made friends by the end of the day.

Have you ever made hay? Share your experience with us.

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Can LED Lighting Cause Blindess?

Here at Provide Your Own, we are a big fan of LED lighting. Recent research has raised the alarm that LED lighting can cause retina damage. Is there any truth to this assertion? Can LEDs really be bad for your eyes, even causing blindness?

Fortunately for LED lovers, the answer is a resounding NO. When the facts are examined, if LEDs are bad for your eyes, then sunlight is at least ten times worse. Let’s first look at the basis for the assertion.

The Research Study

According to a sole news account:

The study found that LED radiation caused significant damage to human retinal pigment epithelial cells in vitro.

Translated,

We irradiated naked retinal cells with intense light from LEDs in a petri dish and they didn’t do so well.

Keep in mind that damage would be done with any high intensity light. Have you stared into the sun lately? How about staring into lasers or high intensity LED flashlights? Think you might have some retina damage?

This research has not been peer reviewed, but is simply an account given by Dr Celia Sánchez Ramos. This fact does not invalid the research, but shows that we have absolutely no real facts – just a lot of conjecture and opinion. What kind of LEDs were used? How bright was the light? What would be the equivalent damage from sunlight?

The Basis for Concern

Dr. Ramos indicated the blue light inherent in white LEDs was responsible for the damage. Also, of similar concern are CFLs (compact flourescents) which have some light in the blue band. In comparison, incadescents have no blue light whatsover and are heavily weighted toward the red end of the spectrum. Scientific American does a good comparison with the various types of lighting as compared to human visibility. Here is a good chart showing the comparison:

Color Spectrums (courtesy Scientific American)

In light of this chart, it looks pretty bad according to Dr. Ramos’ research. Before jumping to conclusions, let’s put things into perspective – what is the color spectrum of sunlight? Take a look at this chart:

Spectrum of Sunlight & Human Eye

Notice how much sunlight is present in the 400-450nm range (where both CFLs and LEDs have emissions). Also consider that light intensity in the shade of a tree is about 20 times of that of a well illuminated office, and full sunlight is 200 times as bright. Even light from a window has twice the light of a brightly lit office, and look how much of that light is in the blue range to the left of human sensitivity. Not to mention all the light in the UV spectrum from the sun.

In light of these facts, you can see that neither CFLs nor LEDs pose any appreciable risk to the eyesight. Granted, if you look into a bright LED you will suffer damage, possibly permanent. Even more so if you look into the sun. Let’s use some common sense here, please.

Balancing the Spectrum

Now that we have established that LED lighting is in no way harmful to the eye, are there any other causes for concern in the spectra differences between different types of lighting? Yes, there are. Take a look at one more spectral graph:

Circadian Spectrum

As you can see both LED (and CFL) lighting has their blue emissions right in the middle of the Circadian band of sensitivity. What this means is that these types of lighting if used right up until bedtime may keep you awake at night. Does this property make these types of lighting bad? No, because sunlight will do the same thing. Natural sunlight does not keep us awake however, because the sun sets long before we go to bed. Even if we go to bed at sunset, the blue part of the sun’s spectrum is blocked by the atmosphere as the sun gets lower in the sky.

Can we just ignore this aspect of these light sources? No. As I have covered in my article Do You Have Trouble Sleeping?, you need to shut off all sources of lighting containing the color blue at least an hour before you go to bed, similar to what happens when the sun sets. That means switching your CFL and white LEDs off (or dim) and replacing with warmer lighting sources such as yellow LEDs. You should also avoid computer use late at night or install color balancing software.

You may be thinking, why don’t I just keep my incandescent light bulbs? One big problem with that is the fact they are being phased out of production and will become difficult to obtain. You will still probably be able to buy them in small wattages which will be great for late night use.

The other factor to consider is the benefits of the blue light present in LEDs. There is a benefit? Yes. Blue light is good for us. Notice that the sunlight has abundant amounts of it. We need blue lighting from when we get up until an hour before bedtime. It wakes us up and promotes a feeling of well being.

In fact, the lack of enough blue lighting in the wintertime gives rise to a malady called Seasonal affective disorder (SAD) or winter blues. The cause is insufficient blue lighting, and the cure is lots of blue light. You can even buy expensive blue lighting or also full spectrum lamps (which are also expensive). What not save yourself the trouble and expense and just use LED light instead?

Lighting and Eye Health Tips

When you buy LED lighting, be sure to get warm white LEDs. Unless you have special needs requiring the extra blue component, avoid cool white LEDs. Those are best used for special spectral needs or if you suffer from SAD. For most usage, warm white is the kind you want. These are almost perfectly matched to human eye response and have only a small blue component. They will also be less likely to keep you awake at night. Their color is also very pleasing – a nice white without a lot of yellow or blue.

Several nutrients are necessary for retina health. The lack of any of these nutrients can lead macular degeneration or other retina problems.

Vitamin A is essential to good eye health. If you have a diet rich in eggs, you probably get enough. However, if you supplement with vitamin D, it can displace vitamin A. The two should be taken together in the amounts shown. Lutein & Zeaxanthin are also essential carotenoids which are lacking in most Americans’ diets.

Summary

LED lighting is in no way harmful to your eyes. It is a wonderful full spectrum lighting, more closely resembling the natural sunlight than any other type of lighting. It is the most efficient and cost effective means of lighting available today and will be even more so tomorrow. Unlike CFLs, there is no toxic mercury. It provides instant, dimmable, directable, flicker-free and pleasant light.

Because LED lighting mimics the sun, using bright white LED lighthing sources right up until bedtime can interfere with normal sleep hormone cycles. The remedy is to shut them off an hour before bedtime and replace them with low wattage incandescent or even better – yellow LED lighting.

Don’t let the fearmongers stop this wonderful new lighting source from entering your home. The future is here, and it is LED lighting.

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DIY Desklamp – from a Pizza Box!

Here at Provide Your Own, we love LED lighting. We also believe the best use of LED lighting is by making your own custom fixtures rather than going out to buy a manufactured light bulb.

An Italian company has the same idea. They have a product where you make your own LED desklamp from a pizza box. In the great spirit of open source, they even provide downloadable plans for cutting and folding your own.

Their version of the lamp uses only a 4″ LED strip for illumination. That comes out to about 60 lumens or the output of a 4 watt bulb. We recommend using at least a 12″ strip (cut into two 6″ pieces), which would provide about 180 lumens or 12 watts equivalent.

Here’s what you need to build your own:

For your convenience, we offer a complete kit (no soldering required) for only $24.95 (over 30% saving over buying the parts separately).

You don’t have to be limited to cardboard either. It is simple to repurpose an old desk lamp. Gooseneck lamps are especially great for this purpose. You can even create your own decorative head for the end of the gooseneck.

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DIY Power Over Ethernet (PoE)

Ethernet (your computer network) only uses 2 pairs of wires. Cat5 cable provides 4 pairs, leaving 2 pairs leftover. You can use those two extra pairs to transmit power (in small amounts) to power remote equipment such as another router, switch or a bridge.

This additional capability is not provided by default. This article provides clear instruction on setting up your own Power Over Ethernet (PoE) network, including making custom adapters for injecting & extracting the power.

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No, Your Dishwasher is Not Broken

My sister in-law has taken to washing her dishes by hand because her dishwasher no longer gets them clean. Millions of other Americans have had the same problem. Many have vainly replaced their dishwashers with new ones only to face the same problem. The problem is not your dishwasher. It is your dish-washing detergent. It has changed. It is not the same product it used to be. A vital ingredient is missing.

While you may have noticed the effects of this missing ingredient in your dishes, you may not be aware of the same problem with your clothes. That is because this vital ingredient was taken out of laundry detergents over twenty years ago. That is so long ago, that most of us just think clothes are supposed to be grungy after a few washings. I am old enough to remember clothes staying clean, but didn’t understand why they didn’t any more until recently.

The Missing Ingredient

The magical ingredient that is no longer present in commercial detergents is tri-sodium phosphate or TSP as it is commonly known. This natural ingredient is made from phosphate deposits primarily found in Florida.

In general, it acts as a detergent, but in the specific case of dishwashers and washing machines, it works to prevent dirt from clinging to the articles being washed during the rinse cycles. You can see this effect most dramatically in the dishwasher. When TSP was removed recently, food particles reattach to the dishes instead of being washed away with the rinse water.

While not as dramatic, the same thing happens to your clothes in the washer. Instead of the dirt being drained away, it remains to make your clothes grungy. I recently noticed a new t-shirt that came from the laundry with so much grey sludge embedded that we had to throw it away. My wife, who is an expert laundress, was clueless as to why this grunging of clothes was happening. Now we know why.

So why was TSP removed from detergents? It is thought by some that phosphates being a fertilizer contributes to fouling of lakes and coastal waters. Many question the significance of TSP in laundry and dish washing, so it is far from conclusive that this removal/ban has any real environmental significance.

My own opinion on the matter is that the run-off from lawn and agricultural fertilizers poses the lion’s share of water pollution. You can see this most dramatically in the waters of Pinellas county in Florida where I grew up. The visibility of the water at the beach is only a few inches and red tides are a frequent problem. This situation is unchanged in over 40 years. The cause is very clear – there is a lot of run-off from people’s lawns which have not only phosphate but also nitrogen fertilizers frequently applied. Compounding the problem is the overwhelming amount of asphalt and lack of trees, both of which contribute heavily to the amount of run-off. Sorry for the rant, but it is clear to my mind that TSP in detergent is not a problem.

Fixing the Problem

Fortunately, fixing this longstanding problem is easy – simply add a small amount of TSP back to your detergents. TSP is easily acquired in the paint section of your local hardware store. It is safe and natural and has many cleaning uses.

It is difficult to determine the exact amount to use, but I believe about 1 part TSP to 6 parts detergent is about right. For dishwashing, that works out to 1/2 teaspooon per load. For laundry, use 1 to 2 teaspoons per load. It those amounts are not sufficient, you can safely use more – extra does no harm.

Learning More

Here is an article by a homemaker’s own pilgramage and experiements in adding TSP back to her laundry detergent. If you want to know more about the backstory of its removal, this article by Jeffrey Tucker is useful and amusing.

Conclusion

Our world is becoming less trustworthy every day. The clandestine removal of TSP from laundry and dishwasher soap is just one example. Politics is useless against this onslaught. Instead, we must be vigilant to watch what is happening around us and take steps to make the appropriate corrections for ourselves. In this case, the proper response is easy – buy some TSP and restore what has been taken from us.

Share your experiences with TSP in the comments below.

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New Online Circuit Simulator

Circuit simulation is a great way to design and debug a circuit without spending all the time to prototype it. One problem in the past was the difficulty in setting up the simulation – picking models, etc.

A new simulator called PartSim changes all that. It is online, free, and drop-dead simple to use. It even links to Digikey parts and has some vendor parts available as well. It also has a nice schematic capture and even does diagramming.

Give it a try.

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