Posts about gear for the lab and test bench.
I set up a smaller version of my mad-scientist stuff at our cottage on Beaver Island, Michigan (45 38 38 N, 85 29 24 W, grid square EN75gp), to record the RF spectrum before, during, and after the eclipse on August 21, 2017. The recordings were successful, and I captured
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It wasn’t too hard for the HamSci guys to convince me to bring a Cesium frequency standard to my portable location in Michigan to drive the HPSDR receiver that will do band recordings for the 2017 Total Solar Eclipse HF Wideband Recording Experiment. I had been planning to use
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I was fussing about signal generator output accuracy because I wanted to calibrate my
HPSDR Hermes software defined radio (“SDR”) so that I could calculate the absolute power input in dBm, assuming a 50 ohm load impedance) based on the dBFS (db full scale of the ADC chip) output from
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Just when you thought it couldn’t get more boring (reference my last post about signal generator calibration…
I did all these careful calibrations of my signal generator to check its accuracy and linearity. Everything looked good, except that the signal reading was about 1 dB low.
HP power meters
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UPDATE: it turns out that my “best” power meter was actually about 0.5 dB off. See my later post for further details.
I want to calibrate my software defined radio receiver prior to doing a bunch of recordings of the ham bands for the upcoming solar eclipse (check out the
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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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My FTS-1050A OCXO has thumbwheels to set the EFC, which makes it convenient to use this frequency standard to generate slightly offset frequencies. I measured the frequency with various EFC settings (compared to an HP 5061B-004 Cesium) and these plots show the results for future reference.
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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