If I was going to do any serious work, I need to have mine calibrated, it's been a long time according to the sticker on it.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
Flukes a great company. We have them come in once a year and they calibrate all of our meters. Even personal ones from home.
One guy had a older DMM, not top of the line by any means. He sent it in for a screen replacement and he gets a call. Fluke told him he had it long enought and it was time for a new one. So they mail him a brand new 87-V which is 399.00 MSRP, for free.
Jim
That's ok, because I have this:
This one liberated from a closing company, was destined for the trash
Wow, thats a nice one.
Looks like it has everything but a built in meter
Mine's closest to this (about 25 years older), liberated from a college lab
http://www.globalspecialties.com/media/k2/items/cache/e44a6f32e15cb53ee479b2697e759e2e_XL.jpg
This is the one I use.
That's the best option. Now that you can get LEDs for pennies each, it's no big deal to blow a few experimenting. Back when a plain red LED (the only kind there was) cost $3 or so each, you didn;t want to make too many mistakes, especially when you were saving odd job money for said parts.
Radio shack has a bread board kit which allows you to build circuits temporarily. No soldering and easy to make changes. Add a cheap DMM, a 12-15v power supply and some diagrams from the internet and you can learn a lot.
Problem is, even though it's free, still doesn't mean it's 'easy'. Just looking the site over, you do have to know something about electronics to interpret what the graphs and sample readings mean when in simulation mode. And here's the catch - if you know enough to read that data, then you know enough how to wire something like a multiple LED circuit.
For example, the second sample on the right, under the "Mixed mode" heading. How do I know a 10K resistor is correct for that circuit? One thing I can do is simulate it and monitor the transistor. Knwoing what the various transistor parameters mean, I can see if 10K is right, too low, or too high based on the response of the transistor. And then try different values to achieve some optimum result.
What an electronics simulator does not do, is just pretend to operate the circuit, in the manner of, if I draw a battery, a switch, and a light bulb, and then flip the switch, the light bulb lights up.
I did try out some of the examples there - for what it is, it's actually pretty nice. Things have come a long long way since back when I used PSpice in college.
Ron,
I Googled "free circuit design software" and got a list of programs for design and simulation of circuits. I suspect one of them may hold the key to your request.https://www.circuitlab.com/ Here's a start.
Lou
I recently struggled with a rather simple (in retrospect) multiple LED circuit where I wanted constant lighting. It occurred to me that there might be some easy-to-use circuit design and testing software (free, of course) that one could use to specify and arrange components in a circuit scheme, then test the circuit before proceeding to the workbench. Anyone know of such a thing online?
Cedarwoodron