Radio design / Own work
MB-470 HF through UHF
A superheterodyne transceiver drawn from scratch since 2015, built on years of keeping a URC-94 and a GRC-171 running.
The design32.7765° N
79.9311° W
K4DIA
Field-built / Bench-tested
Practical radio projects, small applications, and notes from the workbench to the field.
Build / Test / Improve / Repeat
Front and center
Field Record
A printable logbook built around the outing rather than the contact. Put in your callsign, your license class and your state, choose what goes in it, and take away a PDF built for your station. It runs in your browser, so nothing you type is sent anywhere.
- Band plan drawn for your license class
- Quick reference cards for fifteen radios
- Your repeaters, or ruled grids to fill in
- 1 to 60 deployments, four pages each
From the bench
Current projects
Practical ideas
Real-world results
RF / Switching
Manual antenna switching
One radio, three antennas, one knob. Completely passive, HF through 2 meters, with the VNA tests that prove it.
Build sheet
SDR / Construction
RadioBerry V2 portable HF
A 5 watt software-defined radio in a Hammond case, with a real VFO knob, a relay filter bank and an internal battery.
Project planRF / Feed line
1:1 common-mode choke
Twelve turns of RG-58 on a ferrite ring, to keep RF off the feed line of an attic loop fed through an AH-4.
Build sheet
Photo: Buddipole, via
DXZone
Antennas / Decision
Portable antenna selection
Four ways to put up one antenna and change bands from the radio, compared against a budget and an IC-706MkII.
The comparisonBuilt for operators
Small tools.
Useful answers.
Lightweight applications for radio work, written to be understandable, downloadable, and useful with no signal at all.
PDF
Field Record generatorBuilds a printable logbook for your station.
Open
RF
RF Workbench114 live calculators for RF, propagation, transmission lines, PCB and circuits, with charts and a Smith chart. Runs entirely in your browser.
Open
RF
Portable antenna field plannerWire lengths, feed line loss, patterns, take-off and a link budget.
Open
PY
Python utilitiesCalculators, planners and bench helpers.
Coming soon
DOC
Reference sheetsPrintable field references and checklists.
Open files
Take it with you
Downloads
Free to print
Free to pass on
01
Sample logbook
A whole volume, eight deployments, so you can see the format before you commit paper to it. 104 pages.
Get it02
Field reference
Part One on its own. Band plan, frequencies, awards, propagation, antenna math, exposure, checklists. 40 pages.
Get it03
Radio quick reference
Fifteen radios, each card carrying the line that says where it came from. 40 pages.
Get itLonger reads
Articles
Opinion and analysis
with the sources shown
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Station notes September 2026
Stop the hash
Switching supplies are cheap, small, and they
hash all over HF. The two-sided suppression plan I run at my
station, and the one filter rating that catches people out.
Read the article
-
Article September 2026
The plug fits. The wiring does not.
Yaesu put microphone audio on pin 8 in one
radio and pin 4 in another. QEX named the problem in 1999. The
case for a standard microphone and headset interface.
Read the article
-
Article September 2026
Your $4,000 radio ships with a 1930s connector
Amphenol's own part numbers call the PL-259
non-constant impedance. It is still bolted to the back of nearly
every radio sold today. The case for making Type N the standard
on new equipment.
Read the article
What survived contact with reality
Field notes
Short write-ups on installations, portable operations, component choices, test results, failures, and the fixes worth remembering.
No entries yet The first write-ups go up as the current builds finish.