27 November 2016

Si5351 output waveforms

I finally managed to have myself some shack time this weekend and one of the curiosities I had was to check the output waveform of the Silicon Labs Si5351 I2C programmable VCXO. The chip is quite popular among homebrewers thanks to its low price, ease of use, the fact that it generates 3 independent outputs across a very wide bandwidth (8kHz to 160MHz) and that it offers lower phase noise than the cheap & cheerful AD9850/1 DDS modules.

Adafruit Si5351 module

By the way, there are also some versions of the Si5351 that have 8 independent outputs instead of 3, if you really need that many.

The test setup included an Arduino Duemilanove with the NT7S library, an Adafruit Si5351 module and a Tektronix 2225 oscilloscope. I used the middle output for the test (CLK1), which was terminated with a 75ohm load. Oscilloscope vertical scale is 0.1V/div and horizontal scale is adjusted depending on frequency.

First test, 100kHz output:

Si5351 output at 100kHz

Output looks like a clean square wave, with a nice rise time. Peak to peak amplitude is about 650mV into 75ohm, which puts the power output at 0.7mW (-1.5dBm).

30 October 2016

RedPitaya expands line-up with 7 StemLab models

Red Pitaya, the 21st century alternative to laboratory test instrumentation, have just replaced their single product with 7 new models called STEMlab.

The original Red Pitaya is a powerful piece of hardware that can act as a dual-channel oscilloscope or spectrum analyser, signal generator,  8-channel logic analyser, LCR meter, vector network analyser and much more. It has no problem working as a dual-RX dual-TX DDC/DUC HF+6m transceiver and there is even a project for a full featured final product in the works, called the Red Pitaya Hamlab.

It can do all these thanks to the fast 14-bit 125Msps dual-ADC, matching dual-DAC and powerful onboard FPGA, but mostly because there is a strong software development effort behind it. Most of the team was working on high-performance test instrumentation for particle accelerators before Red Pitaya, so they must know what they're doing.

Anyway, back to the new models: the first 3 of them use a more affordable version of the Red Pitaya original board, that has the 14-bit ADC replaced with a 10-bit one. They seem to be aimed at the educational enviroment where functionality and pricing is more important than performance. The naming scheme is intuitive, so here it goes:


Red Pitaya STEMlab 125-10 Starter Kit


24 July 2016

Onion Omega2 - $5 WiFi Linux computer

The Onion Omega2 is a miniature Linux computer with integrated storage and WiFi connectivity. It runs on Linux so it supports many programming languages such as C++, Python, PHP, nodeJS etc, plus there are apps you can install for different purposes.



The base Omega2 model costs just US$ 5 and comes with a 580MHz CPU, 64MB RAM, 16MB storage, b/g/n WiFi, 15 GPIO ports, 2x PWM, 2xUART pins and I2C, SPI and I2S interfaces.

14 July 2016

Baofeng UV-50X3 - new mobile radio

Baofeng just launched the UV-50X3 triband mobile radio and it looks like a jab, cross and left hook to the established japanese manufacturers who were caught dreaming about DMR, C4FM, D-STAR and other leprechauns.



Yes, the chinese manufacturers aren't creative, but they are really good at copying stuff and manufacturing it for a fraction of the price, so the resemblance to some japanese models shouldn't surprise you.

Or maybe the Yaesu FTM-350AR ?
Kenwood TM-d710 looks a bit similar, don't you think ?











27 June 2016

Yaesu FT-891 Operating Manual

The Yaesu FT-891 user manual has just been released and can be downloaded by clicking on the link below:




26 June 2016

Red Pitaya Hamlab - HF/6m 10W SDR transceiver and much more

Red Pitaya Hamlab has just been announced at Friedrichshafen Ham Radio 2016 expo. It is a dual-receiver dual-transmitter DDC/DUC HF/6m 10W SDR transceiver with extended measurement capabilities, based on the popular Red Pitaya development board.



The RF is converted to the digital domain with a LTC2145-14 125Msps 14-bit ADC (comparable to what an Icom IC-7300 uses, for example), so performance should be pretty good. Receiver coverage is 0-60MHz and +15dB preamp and -6/12/18dB attenuators are available for different levels of frontend gain settings.

24 June 2016

Yaesu FT-891 video

Got the chance to play a bit with the Yaesu FT-891 at Friedrichshafen 2016 Ham Radio expo. The radio is pretty menu-driven, even some of the most important menu options (like ATT or IPO) are hidden behind a few button presses.



The expected price for the FT-891 would be around EUR 600, which is suprisingly low; the way Yaesu looks at it is FT-891 + FC-50 tuner costs around the same as a FT-450D.

20 May 2016

Yaesu FT-891 update

Update: The Yaesu FT-891 is the smallest at lightest 100W HF transceiver ever built, at 155x52x218mm and 1.9Kg. Unfortunately the 2A current draw on standby makes it unsuited for truly portable operations.

Among other features worth mentioning would be the 3kHz wide roofing filter (yes, at the 69MHz IF) and the USB port that supports CAT, PTT keying and RTTY data.


04 May 2016

MRF1K50H - new 1500W LDMOS from NXP

LDMOS technology allowed huge improvements in RF power transistors in the recent years, bringing much better performance and efficiency at a lower price point than ever before. A pair of top-of-the-line MOSFETs of the late 80's such as the MRF157 are specified at 1.2KW with 45% effciency in AB class up to 50MHz and would set you back almost US$ 1000 even today. Compared to that, the new generation LDMOS offer more power than that at 70+% efficiency and 1/4 the cost, while they work up to 500MHz.



MRF1K50H is the name of the latest and greatest LDMOS RF part that comes out of the NXP laboratories. It is a small piece of electronics history in itself, being the most powerful transistor ever created in any technology, at any frequency (actually, it's a pair of transistors inside the MRF1K50H, but still applies). It has an output power of 1500W, works at 50V and up to 500MHz, typical effciency is 74% in AB class and the gain is 23.5dB @ 230MHz. There is also another version available called MRF1K50N that has marginally lower gain and efficiency, but compensates with a (30%) lower thermal resistance.

21 April 2016

ESDR - new portable SDR HF transceiver

ESDR is a portable SDR transceiver with HF coverage that is supposed to be released in August. The ESDR features a large color display, digimode decoder/keyer, 2x USB ports and micro-SD card. The required supply voltage is 12.6V and the maximum output power is 30W.


Romania (YO) gets 60m access

Following the conclusions of the World Radiocommunications Conference 2015 regarding the 5MHz band, supported by two local Romanian amateur organisations, the Romanian authority for communications (ANCOM) is granting temporary access for radio amateurs to a channel in the 5MHz band (60 meters).



18 April 2016

Icom IC-7300 and spectrum / waterfall on the PC

Icom IC-7300 is a great feature radio, but the main complaint about it is there's no I/Q output (or at least video output like in the IC-7000) so you can see the spectrum/waterfall display on a larger screen.

Icom IC-7300 waterfall

01 April 2016

Yaesu FT-891 - new HF/50MHz transceiver ?

Yaesu FT-891 is the latest equipment the japanese manufacturer is working on. Although the details are extremely limited, it seems we are talking about a HF/50MHz mobile radio similar with the FT-857 in size.

Update: Yaesu shows the FT-891 at Dayton 2016, seee the following link for more details: Yaesu FT-891 update


28 March 2016

3 years later

I started this blog 3 years ago, a few months after I got my first amateur radio license and about the same time I got my @YO9IRF Twitter account. Looking back, I was less active thant I wanted (about one post every two weeks, on average) so I hope to improve that in the future.

I posted stuff that I'd like to remember years later (like the YO SOTA Marathon or many other SOTA activations), interesting stuff that I wanted to keep my eyes on (like the Xiegu X1M cheap QRP transceiver), I posted a few opinions of my own (such as an overview of portable HF radios) and even did some product reviews (HF-P1 portable antenna or the Icom IC-7300). The IC-7300 article was so popular that, even if it was the only article I posted in a month, it made March 2016 the best traffic month yet.

Blog traffic, from the beginning

14 March 2016

Icom IC-7300 review


Icom IC-7300 is the first direct sampling SDR (software defined radio) available from one of the "big three" japanese manufacturers. This helps it bring a whole new level of performance at an accesible price point, a much more flexible configuration and a set of features only seen in top-of-the line equipment. Real-time panadapter or fully customizable filters are just the tip of the iceberg.



29 February 2016

Icom IC-7300 schematic

Icom IC-7300's schematic just became available, and you can get it here:

Icom IC-7300 Schematic diagram



Not everything is revealed, the RX-ADC is still a blank rectangle although many suspect the LTC2208 is used.

Enjoy !

Odyssey TRX - open-source SDR DDC/DUC transceiver

To be honest, there are so many important things I feel I need to mention about this project I don't even know where to start !



Odyssey TRX is an DDC/DUC SDR transceiver covering 0.1-55MHz with a transmit power of 10mW. It is open source, wich means the community can (and probably will) develop it further to add particular functions and features. It is high-performance, claims VERY impressive receiver and transmitter figures and can control external filters, antenna selection, an automatic tuner or PTT.

16 February 2016

Nice external power pack for SOTA

I just found the ultimate power pack for when going outdoors and working portable. It is called the  Goal Zero Sherpa 50, weights only 544 grams and has 5V USB (to recharge phones/tablets), 19V @ 5A (to recharge laptops) as well as 12V @ 8A (more than enough for any QRP transceiver) outputs.



15 February 2016

Icom IC-7300 available in Japan


Icom IC-7300 is already available in Japan and indeed it's surprisingly affordable. Fujimusen (translation) has the 100W version in stock and it sells for 150984 yen including taxes, wich is 1325 USD / 1183 EUR / 916 GPB.


14 February 2016

Icom IC-7300 first impressions from AB4BJ

Update: IC-7300 available in Japan

The Icom IC-7300 is definetely the talk of the town in this moment and any news about it spreads around really quickly. For those not yet familiar with it,  this is the first direct-sampling SDR transceiver from one of the big three manufacturers,and for more detail you can check out my previous article about it: Icom reveals first SDR, IC-7300. William Jourdain AB4BJ managed to get his hands on an Icom IC-7300, play around with it a little and post a few videos, enough for us to get a better idea on what the IC-7300 can do.






 This last video demonstrating SSB filter and noise reduction capabilities is especially interesting - Icom's DSP functions have always been superb and this falls perfectly in line with what I would expect from the IC-7300.

I am also relieved by the fact that the panadapter display refresh rate seems to be above 25Hz and not around 10-15Hz like a previous video led me to believe.

There is still a bit of speculation about the price and probably the early adopters will have to shell out the usual premium, but expect it to be cheaper than the Yaesu FT-991. Expect the Icom IC-7300 to hit the shelves any day now.

Update: AB4BJ has posted a blog article about the Icom IC-7300 as well, you should check it out.

12 February 2016

Sci-fi series Colony starring Baofeng UV-5R

Colony is a new sci-fi action series set in the near future - the planet is apparently invaded by aliens, the people of Los Angeles are walled in and the city is held under strict military control. It is starring the guy from Lost, the chick from Walking Dead, the guy from House MD and Apollo Creed. Drama, action, mistery, patrolling killer drones, cool stuff.


And don't tell me you didn't see it, because I know you did: there's a damn Baofeng UV-5R on the table, right in the middle of their family drama scene. All the forces in Colony's occupied LA - military, detectives, the resistance move - use it for communications. These are all images from one episode !







So, you'd better learn to field-program Baofengs to prepare for the alien invasion, this is no joking matter.

19 January 2016

World's smallest APRS transceiver

DB1NTO managed to create the smallest APRS transceiver in the world; it's so small that i'm sure it's hard to use with my big bear hands.



It is based off the very small and cheap Dorji DRA818V module I wrote about more than a year ago - a reader immediately saw the potential it had for APRS communications. The Dorji module is already a transceiver in itself (1W output RF amplifier included), it needed a GPS, a nice OLED display, a microcontroller, a Lithium battery and alot of code to make it work.



  Taner Schenker DB1NTO took on this challenge and after months of very hard work, redesigns and a few damaged parts he managed to create this little jewel. It's only 2x3x5.7 cm, weights a mind-boggling 38 grams and does almost everything you could hope an APRS transceiver would do.
For more information you should read this development forum topic, and this one as well. Big congratulations to Taner for this product, I hope it goes into production so we can all have one of these little toys.