Vintage Stansi Ammeter

Vintage Stansi AmmeterThis was a random find on Ebay, just something I came across while looking for something else.  I really liked the look of it, and I needed something that could measure large currents anyways, so I bought it.  I have a Sparkfun digital multimeter, which is a steal at $15 and serves most of my needs as a hobbyist, but it’s best used for low current measurements, under 200ma.  It can do up to 10 amps, but only for 10 seconds.  It’s a useful feature, but sometimes I want to watch a circuit’s current for an extended period of time.  I don’t want to buy an expensive DMM when the Sparkfun unit serves 98% of my needs, so an analog ammeter seemed like a good compromise.  It may not be as accurate as a DMM, but it’s good enough for my needs.

Stansi meter dissasembledI don’t know much about the meter, other than it was made by a company called Stansi located in Chicago, and it has three ranges of measurement: 0-1.5 amps, 0-3 amps and 0-30 amps.  After receiving the meter, I tried it out, and found that the measurements it was giving all seemed to be significantly off.  I was disappointed; I liked the look of it, but I didn’t buy it to be an antique, I bought it to actually use!  I noticed that the connections on the underside of the meter were all corroded quite a bit, so I took all of the connections apart, cleaned all of the posts, washers, nuts and other bits and pieces with steel wool, and put everything back together.  After testing it some more, it seems that all it needed was a good cleaning, the measurements are all very close now when compared to the DMM.  Success!

Stansi meter measuring circuitIf you’re hobbyist like me, and need to measure large currents but don’t want to spend the money on an expensive DMM that you don’t really need, then an analog ammeter may be the solution.  A digital display certainly has significant advantages in terms of speed an accuracy, but if you buy a large meter, it should be easy to get a “close enough” measurement.  In the photo to the left you can see the Stansi meter connected to a BigClive.com RGB controller, and it’s clear that it’s pulling approximately 320ma of current.  It may not be as quick or accurate as a DMM, but there’s something about watching that needle bounce around that an LCD display can’t replicate, and for $20 and an hour of my time, it’s a good value.  I expect to get lots of use out of this meter.

Superflux LEDs header

SuperFlux “Piranha” LED testing

I’m planning an LED floodlight project that will use a lot of square 4-pin LEDs, aka SuperFlux or “Piranha” LEDs.  I hadn’t had a chance to use these type of LEDs until now, so after receiving my order this week I immediately went to work on trying them out.  This won’t be a very technical review, just a quick look at the specs and my experience with testing the LEDs and what I thought of them.

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