Posts about projects that turn into TAPR products.
I am working on a current limiter circuit for a GPS antenna bias tee, and wanted to measure the minimum voltage required by particularly modern 3.3V antennas. I did a very simple measurement of a bunch of antennas I had laying around, and these are the results.
I put a
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As part of the HamSci Solar Eclipse experiment, I recorded wideband data from my SDRs on the theory that capturing the data for later study might be more productive (and less stressful) than trying to do measurements in real time. I think that theory played out very well.
I
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Several years ago I designed a little circuit board called the T2-Mini that provides life support for one of Tom Van Baak’s very wonderful picDIV PIC-based frequency dividers. The idea is to convert the 1, 2.5, 5, or 10 MHz output from a frequency standard to a one pulse-per-second
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My latest project has turned out to be my most complex (so far…), involving both new-fangled hardware and quite a bit of software, but it’s now finished and working well.
Meet the TICC, an Arduino Mega 2560 shield that implements a two channel timestamping counter that has resolution of better
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Just finished the second piece of my multiplexed measuring system. This one isn’t too sexy, but is a necessary part — a pulse-per-second (“PPS”) distribution system. This enclosure contains 4 TADD-3 PPS distribution boards. Each board has 2 sets of 3 outputs, plus 2 RS-232 level outputs. So, there are
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The TASS switch system made a design compromise that means its RF performance has some variation depending on which combination of ports is selected. When using a port that’s not at the far end of the board from the common, there is a transmission line stub of varying length that
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Several of the design projects I’ve done for TAPR were part of a larger concept I’ve been working on for several years: a measurement system that will allow me to compare the pulse-per-second (PPS) outputs from a bunch of test devices against one of several reference clocks over long time
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I didn’t even think of it when I was designing the TASS-R relay switch system, but the relay board can be used with an HPSDR Hermes, ANAN-10, or ANAN-100/200 radio without requiring use of an Arduino or other controller. These radios provide 7 open collector outputs that
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