Posts related to time, time interval, and frequency generation and measurement.
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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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 rediscovered a post from Corby Dawson with pinouts for the DB9 connector on the above OCXO and wanted to preserve the info here. Thanks, Corby!
1000B 1000A-100 1200 and 9110
1 EFC ground EFC ground EFC ground
2 EFC +- 10V EFC +- 10V EFC 0 to +10V
3 I did two hour measurement runs of three ’60s vintage Sulzer frequency standards against perhaps the best modern quartz standard available. These are pretty amazing results.
Over the years I’ve acquired a whole bunch of Sulzer OCXOs. One is dead, several have oven temperature control problems, but I have three powered up in the rack that still work amazingly well.
This one, Sulzer #3, is particularly interesting. It’s not on the standard 2.5 or 5 MHz
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More twiddling of the OCXOs this afternoon.
