Category: Designs

Mini-PC for transceiver

What do the radio hams miss on their radio shack the most? The most lacking is free space for the next lumber, as in the example in the shack of Mark MW0RKB. One of the ugliest and senseless boxes that are waste of space, make noise and draw a lot of expensive electricity, are PCs […]

HF amplifier with MFR101

In 2018, NXP introduced new MRF101 and MRF300 power transistors to the market. They are designed for medium and high power levels in the radio frequency range, where the offer is not so rich. Why are they extremely interesting to the amateur radio community? – First of all – they are cheap thanks to the […]

ADALM-PLUTO tuning

The SDR Active Learning Module  ADALM PLUTO from Analog Devices is used by many OM’s for working satellite QO-100. This is due to the attractive price and the excellent SSB-Modulation. No additional up- or down-converter are needed. Nevertheless some optimizations are possible. Installation in an aluminium housing avoiding radio frequency radiation Reducing frequency drift by […]

HackRF with PortaPack – Educational SDR Transceiver for 1 MHz to 6 GHz band

Chinese manufacturers have recently specialized in providing interesting and cheap radio toys, which are clones of open-source projects. An example, next to the recently popular NanoVNA analyzer, is the HackRF micro-transceiver offered with the PortaPack panel, which allows you to conduct various radio experiments. HackRF is a SDR (Software Defined Radio) module that contains transceiver […]

RF level meters with AD8318

It is not necessary to justify how important a radio signal meter is for a radioamateur, especially when entering the frequency ranges above 1 GHz. There are inexpensive meters available on the market (EXAMPLE), but you can do better by yourself 😉 using an inexpensive module with the Analog Device AD8318 IC. The schematic is […]

Properties of the horizontal dipole above the ground

The radiation pattern in the vertical plane perpendicular to a horizontal dipole over perfectly conducting ground is given by the equation: where α is the angle to the horizon (the radiation characteristics in the facade perpendicular to the axis of the dipole), and h is the height above ground in electrical degrees (where 360 electrical […]

Mosley MINI-32-A antenna test

Mosley MINI-32-A antenna test: assembly, failure, repair, measurements and start of HF5L/p in IARU SSB R1 Fieldday 2019 contest Field work, e.g. FieldDay contests – is a great opportunity to check in practice the suitability, strength and equipment parameters. We have made some test for the Mosley MINI-32-A antenna. Why did we choose this antenna? […]

ADALM-PLUTO development kit for (not only) Es’hail-2 satellite

Adalm-Pluto (Analog Device) SDR radio starter kit was received for experiments by courtesy of Michał Trzaskowski from Richardson RFPD. This device gives completely new possibilities when it comes to cooperation with the first geostationary amateur satellite Es’hail-2. To name a few: thanks to the large bandwidth of the receiver (up to 6 MHz) it is […]

ICOM IC-705 SDR – A new toy for trips

Icom has presented at HamFair, taking place at the Ariake international exhibition center on the artificial island Odaiba in Tokyo from August 31 – September 1, 2019, a new compact portable QRP IC-705 transceiver, working with the use of SDR technology. Main Features: TX Bands: HF, 50 MHz, 144 MHz, 430 MHz plus 70 MHz […]

Xiegu G90 – Transceiver for QRP operations, and digital emissions

QRP work has many advantages, especially during holiday trips. I have been practicing it for years – especially from the Greek islands. However, I have a problem: the elephant has stepped on my ear which I use to receive CW. Last time I was actively practicing CW on the RBM-1, as an operator of “Operation […]