Posts about gear for the lab and test bench.
Each year at the Dayton Hamvention, the folks at Mini-Circuits have a bunch of odds and ends they sell very inexpensively. Over the years I’ve gotten tons of SMA attenuators and jumper cables, and a few amplifier blocks. I’d never looked closely at one of the amp blocks until last
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It’s well known that just about all oscillators drift, or “age”, in frequency with time. In crystal oscillators, the most drift occurs when the oscillator is young, and over time the aging rate decreases. Power-cycling the oscillator results in a new stabilization period before the aging rate stabilizes. The best
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My faithful HP 5065A Rubidium standard, which had been converted to a “Super” model, developed an intermittent sickness and back it went to Corby Dawson for him to perform his magic. After a realignment and fixing an intermittent connector ground, it’s back in the lab and working well, though minus
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I was lucky enough to find an HP 5061B cesium standard with what I think is a virtually new high performance (option 004) tube. These are rare because the high performance tubes burn up their cesium supply much more quickly than the normal ones. But you get much improved stability
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I set my HP 5065A Rubidium standard to the 5071A. Unlike a Cesium clock, the Rubidium system does have some drift so it needs to be tweaked occasionally. I plan to come back to this post every few months to update and see if we can determine the aging rate.
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I compared my old HP 5061A cesium standard against a much newer HP 5071A with high performance tube. Cesium standards are tweaked by adjust an electromagnet in the tube; this adjustment is called the “C Field.” In the 5061A you need to set the C Field manually, but the 5071A
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This is the first of several boring posts where I’m documenting the offset of a couple of my frequency standards so that I can come back later and determine aging rate.
This is my Oscilloquartz 8607-008 BVA quartz oscillator. I don’t know the last time it was adjusted, but when
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In Part 1 I described some background about SDR dynamic range as an introduction to the measurements I did on a RTL-SDR.com v3 USB “dongle” SDR. Now for the results.
I wrote a Gnu Radio program to help measure the dongle. It tunes the dongle, sets its front-end gain,
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I’m using several USB “dongle” SDR sticks from RTL-SDR.com. These nifty $20 devices can receive from 100 kHz to above 1700 MHz. They have a low noise amplifier in the front end that is adjustable from 0 to about 50 dB gain. I wanted to determine the impact of
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I’ve continued processing the data generated from software-defined-radio recordings I made during the 2017 solar eclipse at my fairly isolated and low-RF-noise location on Beaver Island, Michigan (45 38 38 N, 85 29 24 W, grid square EN75gp). The nearest AM station is about 28 miles away, so it’s a
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