SDR and why you should make the move to the new technology

SDR and the Promise of the Future is here!

5/8/2019 ~ Update on my SDR Stations

I now have two separate stations up and running and there is cause to share this with the blog readers.

•  The first is my Omnia SDR which covers four bands (60, 40, 30 and 20 Meters). This is running on an RPi3 (NOOBS 3.0)  and Quisk. The secondary sound card is built into the Logitech H390 Headset Microphone. I have this mating with two amps so can I deliver 600 watts on 40 and 20 Meters. The rig gets excellent audio reports and I even managed to snag a 60 Meter contact running 60 watts.
• The second station uses the RPi2 (NOOBS 3.0) and for the heavy IQ stuff this is done with a StarTech 7.1 sound card and the audio out / mic in is done with a small dongle type sound card ($7). The Transceiver is the Softrock V6.3 and I have plug in coils to cover 80,60,40,20,17 and 15 Meters. This rig can also be mated with my SB200.

So for the reasons mentioned by John Linford in the RSGB presentation, this is falls right in line with the paradigm of minimum in hardware and maximum in software. I get excellent audio reports (the energy is within the spectrum and it is not yellowy). It also can be tuned precisely on frequency. Variable bandwidth tuning is superb and there is no problem with working the digital modes directly without any adapters.

So excuse my enthusiasm but I am actually busy making contacts and exploring the new features and functionality of my two rigs. SDR is the new wave.

73's

Pete N6QW

5/6/2019 ~ FT8 & WSPR Update.

Yesterday  I loaded up a 32GB SD card and setup the RPi3 to operate with the Omnia SDR. I also downloaded the WSJTX software. Boom as of yesterday there is a new version for Linux and it does not expire in June. Thought the few readers of this blog might like to see some screen shots of the setup as used on the RPi3 and the Omnia. All this with a $35 computer and $14 SD Card.

5/5/2019 ~ More exciting SDR experiences.

[Our hobby is just that and each of us chooses how to interact with the hobby and with others who share our slice of the pie. Some like to push the envelope on the newest and latest technologies like putting a ham satellite into space while others are using nothing but homebrew rigs only on CW. In between we have many roads and many adventures. All of us do have one common goal ~~~ enjoyment. We are co-equal in our pursuits and no one can claim (or should claim) his is the only way to go. 

I am immersing myself in SDR as I see it as a challenge and a learning experience. Throughout my 66+ years doing this (including early experiments with a CK722 transistor in 1953/54) I have seen many changes in the hobby and our rigs. But today the new technology showing up at the market place is astounding. A $35 computer --hard to believe that it is so cheap and can do so much. 

Sure I can't see every component on the board. Nor could I homebrew a Raspberry Pi; but for me personally I do not need to do that. What I want to see is how it makes me enjoy my approach to the hobby. The RPi has exceeded my expectations and my foray into SDR is enabling me to fully enjoy its capabilities. I respect that others have different views and that it is why this is such a diverse hobby with something for everyone.. Pete N6QW}

Sometimes you just get lucky. Early this morning (before 0 Dark 30) -- I went to the shack and finally figured out how to make FT-8 work with the Omnia SDR. The magic decode is to use the rig listing for the AE9RB Peaberry  V2. Then to use DGTU key, set up for VOX (turn on the VOX button), Mute the receiver and then use CAT control on the USB port. For the radio in/out use the Peaberry selection. Bottom line made my 1st FT8 contact (more than QRP) and was slightly underwhelmed. It was the technical challenge to make it work and not so much the actual FT8 contact was the real buzz.

Just finished a run on WSPR and at two watts was spotted mostly in the US.

I was able to download the FT8 from the Princeton (K1JT) site but there is a note that this version for Linux will die on June 7, 2019. After down load to the RPi I was able to install it right from the download directory. 

I also worked Japan JA2QXY on SSB. Hawk (JA2QXY) is near Nagoya and running a 5 element homebrew beam and 1KW homebrew amp --his rig was a TS870 to drive the amp. Needless to say he was pounding into the left coast.

The operating position looks a little bare with just the Raspberry Pi, the small Omnia SDR and the keyboard/mouse and the monitor. I am using a Logitech H390 USB headset which actually has a built in sound card so just plug in the headset to the Raspberry Pi and you have a separate sound card for the audio out and mic input.

I have real respect for the $35 RPi computer --it is doing a lot of heavy lifting.

73's

Pete N6QW

5/4/2019
How to key an External Amp with the Omnia.

The Omnia SDR has an Opto-Isolator on board which cannot directly key an external amplifier. This is left up to the user. So I designed an interface to tap into that opto-isolator. Heck who in their right mind would run the Omnia QRP???? 

BTW you can adapt this circuit to make it a universal keying circuit by including a 4N35 opto-isolator and a simple PTT for the input would make this useable to turn on directly an SB200! It is powered from a 12 VDC source. The Reed Relay was selected because it is fast acting and draws low current.

Sure is nice to have some tribal knowledge!

[BTW you can get a built Soft Rock Ensemble (40,30,20M) for about $125 from Five Dash. You would also need a StarTech 7.1 sound card about $35 and a Raspberry Pi3 about $35 and of course a monitor (HDMI) and a keyboard mouse combo. So with a bit of scrounging around $250 would get you on the air with a software defined radio having all of the wonderful filtering, accurate and stable frequency control, waterfall display and many other refinements like AGC and a 200 Hz CW filter. SDR for the masses -- Linford's prediction is a reality.]

73's

Pete N6QW

5/3/2019 ~ Huge Progress Today.

Today I bit the bullet and loaded a new 32GB SD card with NOOBS 3.0 and using my process on the www.n6qw.com website easily installed Quisk 4.1.15. I am not sure how to use the latest Quisk -- as there is some arcane thing that has to be done that I have never seen before. If you want a Zip file of the old Quisk drop me an email to my QRZ address.

Boom now FT8 can be decoded as well as WSPR. So Far receive only as I can't quite get the right parameters to make it transmit. That hamlib stuff is real CRAP!!!!!! [Confusion Reins And Problematic]

So if any one is using a RPI and knows what setting to use please share.

So OK my strong suit is hardware (or so I tell myself) but I can see the need for an "API" so that the frequency changing can be done with an encoder. I do know that in NOOBS 3.0 there are links to tie in an Arduino Uno. So I can see the Arduino doing the tuning maybe communicating over the I2C or SPI links and the frequency is changed using a big old FAT KNOB! So OK you out there whose strong suit is software --tell me how to do it.

This latest adventure has revolutionized the hobby for me. Get on board --soon all commercial rigs will be SDR

73's

Pete N6QW

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I have been "dabbling" with SDR rigs (yes I call them rigs because I built them) for almost 9 years now and it is only now that I am fully appreciating their awesome capabilities.

A friend in the UK put me on to a you tube presentation at the 2017 RSGB Convention by John Linford, G3WGV. This is a must see video.

Essentially John, makes a comparison with the two competing technologies that of the HDR (hardware defined radio) and the SDR (software defined radio). 

John presented  many factors for comparison including cost, capabilities and of course the all important user interface. He also states (from a 2017 vantage point) that in 2 to 5 years virtually all commercial ham radios will be SDR. Just look at the ICOM 7300, its current popularity and price point (soon to likely see about $1000). In about three weeks we will have the Dayton Hamvention (Xenia just doesn't flow like Dayton) and it will be interesting to see the hardware. I think the new FT-101 will be there as well as perhaps some new upstarts, especially from China. The one and only time I went to Dayton (over 10 years ago) I stopped by a booth manned by two guys with a laptop --the company name was FLEX radio and today that company is a leader in DDC SDR radios. 

My Omnia SDR with the RPi2 and the Motorola Lapdock is in the $250 range. Certainly not a 7300 but then again only 25% of the price. My main bands of interest are 40 and 20 Meters so I am good to go. With my Softrock V6.3 I can do 80-15 Meters. Here are some screen shots of my Quisk Display. Not bad for a free software download. I mentioned the empty block --look for 7.155 and then you will see it went to 7.155 000

The dye in the wool HDR guys complain about no "knobs" (C'mon guys this is a radio related website). But G3WGC shared his totally homebrew rig with an amazing front panel with just the right amount of knobs. Upon looking behind the panel is a small form factor SBC (Single Board Computer) running Windows 10 that handles the API (Applications Programming Interface). With his homebrew API he can iterate the SDR software so that he has a main tuning knob, volume control and a few other "knob" functions.

I need to learn how to do the API as I suffer from a Terrible Malady called FFS (Fat Finger Syndrome) and somehow I always overshoot the mouse and have trouble pointing and clicking on the PTT button.

Jim Ahlstrom N2ADR, had written an amazing SDR program called Quisk and that is what I am using on the RPi2. Each day I learn something new about the program. For instance just yesterday I was wandering over the GUI interface and spotted a blank looking area. I found that if you type a frequency in there and press enter on the keyboard -- Boom you are on that frequency. My Omnia SDR board covers four bands 60, 40, 30 and 20 Meters. It will even jump bands based just on the frequency being typed in the space. I don't know if the current uBitx with the JackAl display can do that -- but that sure is nice to have on my Omnia SDR.

The Omnia was a later offering from a small group who took on the work of AE9RB who was selling the Peaberry V2. The Omnia was originally intended to work with HDSDR software which I never liked and that is why it has been in the bin for a couple of years. Since I have migrated the Omnia SDR (Peaberry V2) to Quisk a whole new world has opened up for me.

I had an amazing QSO last evening with my Omnia talking to N5SDO, Dave in NM on 40 Meters. He and I often talk on 40M. Dave last night was using a FLEX 5000 running Power SDR (developed as an open source by FLEX) and then announces --time to identify --suddenly appearing in my waterfall display was N5SDO. Now I thought that was really cool. A gadget --yes but shows the power of the Computer and SDR

For some unknown reason the RPi does not like to load WSJTX 2.0 as there is one or two files it cannot find on the download and subsequently aborts. If I can fix that then the Omnia SDR has possibilities for FT8.

The Future Indeed is Here!

73's

Pete N6QW