nanoBeacon: a simple personal CW beacon

There are times when you wonder if your receiver and antenna are really working as they should. The band is dead, or empty, it’s the middle of the day, the D-Layer is sponging up every radio frequency excitation. Perhaps you can hear a few signals, but they are fleeting — and you need a steady and predictable signal source for a proper test. An RF signal generator will give you a steady carrier, but there are times when you’d prefer to have a true CW beacon to tune onto. This simple, general purpose multiband CW beacon can be run up on the frequency (or frequencies) of your choice, is powered on a 9V transistor radio battery, and can moved to attenuate to the desired signal level, for radio receiver system testing purposes.

Scratch-built 8-band HF SSB/CW transceiver (EI9GQ) – Part 2 – Receiver completion

There’s a reason why most homebrew transceiver kits and scratch-built projects are monoband and single mode — theres a chance you’ll finish it, or at least, get it working for a while. Building a multiband HF transceiver is a big job, as any homebrewer who has attempted it will tell you. It may take years.

SP-2B2C: A video series on the design and construction of a Dual-Band 2 Channel QRP CW rig

My radio projects have involved a build and test effort, often spanning 3, 4 or even 6 months, culminating in one long, detailed blog post which was assembled over many months and a video that serves the dual purposes of showing and explaining the rig followed by an outing to one or more SOTA summits.

Low-band AM Tx: Chassis and finishing

This post closes off the 160 and 80m ‘Low-band’ AM transmitter series, with a description of the chassis construction, fitting the assemblies into the chassis, and front panel finishing.

Low-band AM Tx: Power supplies

Complete 500W variable regulated DC power supply assembly.

This post describes the power supplies for a 200 watt AM transmitter. There are four independent DC regulated supplies. The ‘high tension’ (HT) supply delivers 0 to 100 volts at 5 amps steady to the modulator, and is sized for a continuous 200 watt AM carrier (with 800 watts of peak power in the sidebands). Two regular 12 volt linear regulated supplies power the 12 volt circuitry (independent 12 volt supplies is a way of keeping digital and other noise off the modulator and driver stages).

Low-band AM Tx: Pulse Width Modulator and Preamp

This post describes the modulator section of a 200 watt dual-band (160 and 80m) AM transmitter, built during the COVID-19 first-wave lockdowns in Melbourne. The transmitter is fully solid state, runs cool to luke-warm at 85 to 90% efficiency, and produces high quality AM on the two lower amateur bands.

Low-band AM Tx: RF Deck

‘RF deck’ is a term that describes the RF power modules in a transmitter or linear amplifier. In this 200 watt 160 and 80m AM transmitter, the RF deck consists of two identical FET RF modules each with its own driver, an RF power combiner, the band switched Low Pass Filter module, a Transmit/Receive switching relay, and an SWR and RF power sampling module.

Low-band AM Tx: Digital VFO/Controller

Lockdown has made 2020 a year unlike any other. Melburnians were dealt a long and painful period of isolation with a CoronaVirus second wave, from around July to September, still in force, and looking like continuing to (at least partially) keep us housebound for some months yet. Days merge together, work and leisure time is largely indistinguishable. People are rediscovering reading, knitting, and endlessly bingeing TV. Makers are melting solder and stringing wires in the air.

Ten Tec Model 1056 DC Receiver – is it any good, and what to do with it?

One of life’s simple pleasures is to rediscover something that bought you engagement and enjoyment in the past. And in COVID lockdown, stuck at home, it’s the perfect time to rummage through boxes in dark corners to sort, throw out, and rediscover old treasures. So it was that I came across this Ten Tec direct conversion receiver board, built around 20 years ago.

Something old, something new: A four-band 5W/50W SSB/CW transceiver (‘Summit Prowler 7’)

‘Summit Prowler 7’ is my name for this scratch-built multiband SSB and CW transceiver. This rig covers four of the most popular portable, Parks and SOTA bands — 80, 40, 30 and 20m, at a power level of 5 watts, but with an in-built switchable 50 watt power amplifier, so that you have the option to call up the extra power if the going gets rough. The rig weights in at around 1 kilogram or 2.2 pounds, about the same as an FT-817, and is similarly sized. It’s a rig for a wide range of portable situations, and is equally at home on the shack bench.