Baojie BJ-UV55 - new chinese mobile VHF/UHF radio

Baojie BJ-UV55 is the latest thing to come out of China in terms of amateur dualband (VHF + UHF) transceivers. As one being familiar with recent history should expect, it should be sporting a a very nice price, a nice package of features and a good build quality; and of course, some imperfections that an inexprienced company would make.

Yes, Baojie does sound like Baofeng, probably they're not related but the products seem to go by the same style; also, the BJ-UV55's menu apparently looks alot like (read that: almost identical to) the Baofeng UV-5R's.


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Codan Envoy - SDR-based HF transceiver

The marine radios manufacturer Codan has a new series of radios called Envoy, wich seems to be a very advanced HF transceiver. It is based on SDR technology and has 2 types of modern interfaces (one for use as a base station and a more compact one for use as mobile), it is IP capable and can be reprogrammed remotely via internet and has an internal software modem that supports high-speed data, chat and email.

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My first contest - CQ WPX SSB 2013

Last weekend I have participated for the first time in an amateur radio contest, just to get an idea about how it is: the CQ WPX SSB 2013 contest. I only had about 4 hours of continuous operation, and I just preferred to search and pounce as it seems the most effective way for a low power station. I entered the rookie / QRP / 20M category using the SDR transciever set at 5W output and the ground plane vertical, and had no problem working most of the stations I could hear; maybe just 3 or 4 did not reply at the first 2-3 calls so I decided not to waste time and move on.

I still managed to make 91 contacts that include a few new entities for me as well (hope they EQSL!), and the claimed score is 7371. It is way too low to think about any noticeable result, but I think with full 48h dedication it could have been rather competitive; I'm already making some plans for next year. Maybe a good sleep before the contest and a better antenna - wich might be useful in the second day, are all I need for now.

Developing a HF transceiver around an Arduino

As you probably know, the Arduino platform is a very useful toy for development of electronic gizmos, and after I saw the Myriad RF project I started thinking how a small portable HF transceiver could be developed around the versatility the Arduino provides. The idea is to keep in line with the Arduino philosophy and level of knowledge, so the end product should be fairly simple and affordable, but still offering alot of fun.

These are my targets:
- 8-band SSB transceiver (LSB: 80m/40m, USB: 20m/17m/15m/12m/11m/10m)
- weight: 500 grams
- output: 10W
- sensitivity: 0.5uV
- consumption: 400mA@13.8V standby / 2.5A@13.8V TX
- display: mode, frequency, step, supply voltage, S-meter, SWR
- encoder VFO with 2 selectable steps
- bandswitch button


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Raspberry Pi as a WSPR beacon

Probably alot of you know what the Raspberry Pi is - a US$35 micro computer the size of a credit card that can be used for alot of simple but cool projects. Well, some guys at the Imperial College Robotics Society in UK found out that you can actually output a modulated clock signal on one of the GPIO pins to act as a small RF transmitter, then Dan MD1CLV and Guido PE1NNZ took the idea further and implemented the necessary coding in order to make it a working WSPR beacon - project's name is WsprryPi .

Considering the limits for the GPIO output (TTL 3.3V @ max 50mA) we can't expect too much output power, 10mW (+10dBm) into 50ohm is a reasonable figure while about 20mW is the technical limit. One issue would be the fact that the output signal is a square waveform therefore rich in harmonics and a low-pass filter for each transmit frequency is mandatory (especially if you want to boost the power a bit); considering it covers from 0 to about 250Mhz, if you plan to make a multiband beacon out of it you will need alot of filters. At the moment it needs a permanent internet connection for time synchronisation, but i'm sure some handy fellow will implement a GPS time reference to make it completely standalone.

X1M - portable chinese HF transceiver

The Xiegu X1M is a recent attempt at HF portable QRP transceivers straight out of China, and it looks like they are on the right way: small and lightweight - check, simple and robust design - check, low power consumption - check, CW and SSB modulation - check, full HF coverage - check. Yes, it is not the prettiest girl in school ... but who cares when it is the cheapest ? No really, it costs about US$260 as a kit or US$300 assembled, half of what an Yaesu FT-817ND does.

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Myriad RF - an Arduino transciever shield

Lime Microsystems is a rather new and fabless company specialised in multi-band multi-standard transciever IC's; their only creation so far seems to be the LMS6002D, wich is a chip no bigger than the nail on your index finger but includes all the logic necessary for a configurable broadband transciever IC supporting all the modern 2G, 3G, 4G, CDMA, HSPA, WiMax or LTE standards: two ADC's, two DAC's, three low noise amplifiers, filters, mixers, gain control, the lot.

Unless you are a seriously antisocial tech-freak that won't sound extremely fascinating, luckily the best part is still to come: they have worked together with their distributor Azio and have implemented the tiny creation in a board called the Myriad RF, wich is basically an Arduino shield that houses an equally versatile transciever, allowing a ... myriad of RF-based projects to be prototyped around these two tiny boards; the Myriad RF does everything radio-related and the Arduino controls it and interfaces with the user and other pheripherals. Everything (software, PCB design etc) is open-source and it becomes a great learning tool, plus it brings advanced radio technology closer to hobbyists.

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