General amateur (ham) radio.
A lot of us use Anderson PowerPole connectors for DC power distribution. There’s a nearly universal standard to use red and black housings for 12 volt-ish (e.g., 13.8) lines, with the housings arranged per the “Orange County RACES Standard” like so:
Of course, to make
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I’ve been looking for an antenna switching solution to use in my new ham station. I have several antennas for HF and 6M that all connect to the same amplifier in the shack, which has only a single output connector. A remote switch at the tower (about 20 feet from
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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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One of my Gnuradio projects is a tool that records IQ data covering 375 kHz — which is enough to capture an entire HF ham band (except for 80/75M). A neat trick is to retransmit such a recording to allow local receivers to tune in The Signals From The Past
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I’ve noticed that my SDR setup, an Apache Labs Anan-7000DLE transceiver used with the PowerSDR software, seems to rest the S-Meter at a quite high level when there is no signal present. This is unnerving when I try to compare my local noise floor with others who claim noise levels
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Many people use HF transceivers in situations where they back the power down significantly from full output. Examples are driving an amplifier that may require 20 or 30 watts for full output, or using a transverter that might want just a few milliwatts.
The method many modern HF transmitters use
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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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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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