Saturday, May 30, 2015

SO3R sorta In CQ WPX CW contestI


I recently bought a Flex 6500 and decided to play around with all those panadapters in the CQ WPX CW contest.  I call it quasi SO3R.  My goal in the contest is to increase DXCC total and band fills on DXCC and generally just play around.  

The programs I am using are SSDR, SmartCAT, DAX, SDR-Bridge, DDUTIL V3, VE7CC cluster client, DXLab suite, and WriteLog.  All of these mesh together in a functional unit.  I have 3 panadapters open one each on 80, 40 and 20.  I also had 15 open but the band closed.  Each skimmer is connected to its own DAX channel and is controlled through a telnet client in SDR-Bridge.  WriteLog also connects through SDR-Bridge and is tightly integrated.  The writelog band maps are populated with stations through Skimmer and through VE7CC spots.  To enter data into the correct Writelog data window, I can click a station on a band map, or on skimmer and the data will be copied into the correct entry fields.  I can also type data.  To choose a band I use the keyboard up down arrows or click the pan, or click the skimmer, or click the bandmap.  When I change bands in this manner, the TX is assigned to the correct panadapter, and the correct antennas are chosen.  I have a amp/antenna system that follows TX.  When TX is on 20M my 20M xmit antenna is chosen and my amp switches to 20M.  My 20M antenna is flat so no tuning necessary.  Same with 40 and 80.  Change bands and everything follows.  For receive I am using a Wellbrook large aperture loop antenna on all bands so I have good strong low noise receive signals.  The loop preamp does not distort and is bullet proof so far.  

Included is a video I made to demonstrate but the quality is only fair since I have 3 skimmers, 3 panadapters, and I'm using a remote base hookup to get audio and video into my screen casting program.  All of that especially the screen casting program takes my computer to the 85% + performance load.  With the screen caster off things are perfectly smooth even with all of this video/audio activity.  

This is not true SO3R or SO2R but actually is very close and quite amazing.  By populating 3 skimmers and 2 bandmaps the stations presented to me are pretty much stations heard at my QTH real time.  My goal is to increase DXCC and DXCC band fills and this setup accomplishes that quite nicely.  If I do get a new one I simply enter the data into DXLab.

Since my RX and TX antennas are separate SO2 or SO3R is simulated but since I am not full duplex it is not quite SO2 or SO3R however the QSK in this configuration is very fast and all of the data in skimmer and band map fills some of that gap in operation.  I would have to become a much better contest op to
 leverage this setup but it's not impossible to use this



I did get all three band maps running by upgrading my Writeog to the latest version.  The latest also has a switch which allows the band maps to readout freq in the same direction as skimmer



73  W9OY
  

Friday, May 29, 2015

Flex APF


Flex has been doing some upgrading on the DSP in recent software releases, so I did a quick video demonstrating APF in the 1.4.12 version of the software.  It's important to list version since the software is continuously upgrading and what may be true this month may be better next month depending on what's been improved.  

The present APF has a slider which gives between 3 and 12 dB control of gain when APF is selected, but the APF precedes the AGC loop.  If you want more gain beyond APF you simply increase the volume control.  

In my tuning I usually set the AGC-T to a "best" level for a given set of band conditions.  AGC-T sets the level where the AGC starts to react and reduce gain.  For weak signals the sweet spot is to not have the AGC-T too high where AGC is fully engaged or too low where the signal is below receive threshold.  This is useful because it tunes the radio to a given band/antenna for best performance.  For strong signals you just let the AGC reduce the gain.  Once set for a band there is not much need to "ride the gain" as I have seen others complain.  If you are talking to some really loud stations you can turn the AGC-T way down and band noise is virtually completely eliminated. 

The effect of APF is more evident when used with wider bandwidths.  The control was introduced years ago as a means to get better bandwidth in the days of crystal filter radios.  If you went from 500hz to 250hz to 125hz crystal filters bandwidth reduced but distortion due to ringing and delay went up dramatically.  In a SDR radio where the filters don't ring APF is less useful, but still can provide a way to better tease intelligence from the noise, and this is the bottom line.  What we want is improved signal to noise.  

In the video I set AGC-T where I like it and AGC to fast.  I next set the band width to 250hz and tune in a typical 15M CW signal.  We are listening to AO150A the ITU special events station knocking off all comers.  The band noise at 250 hz is averaging -112 dBm and at 50hz is -120 dBm.  AO150A is about -110 to -105 dBm according to QSB.  I try various demo's of APF trying to switch APF off and on during his transmission.  Midway in the video I switch from fast AGC to AGC off.  This sets the stage gain at a fixed level and makes the APF act more like how APF would work if it followed the AGC loop.  I run through similar bandwidths and off/on scenarios.  



I think if you focus on the S/N and noise reduction provided by APF it is quite effective especially in wider bandwidths.  As you reduce bandwidth a great amount of noise is already eliminated and in that scenario APF is less effective.  


73  W9OY

Friday, May 22, 2015

KX3


I've owned a K-1 elecraft CW QRP radio for many years


Back in 2004 when hurricane after hurricane was blowing through Florida this little radio was a true friend.  The first night of Francis at 18:00 my power went out and that was that.  Earlier I had charged up a battery so I ran some coax from the station out to the family room where I was camped out.  Soon enough darkness fell and it was play with the K-1 or listen to hour after hour of some weather man go "yea Charlie it's really blowing over here..."  No kidding dude it was blowing over my head too, that's why I sent my family out of town.  I flipped on the K-1 and started tuning around.  Long story short I made dozens of contacts that night while 100 mph winds were coming ashore a mile from my house and it was damn nice to have the company of fellow hams.  

I bought the KX3 because it's touted as a "SDR".  In my opinion I'm not sure exactly what it is. 



When I look over the diagram it ever so much reminds me of a SDR-1000 three card stack from a decade ago


Both radios use a direct conversion receiver to take RF and directly convert it to a baseband AF signal which is then fed into a ADC (analogue to digital converter) which digitizes the signal and then a "DSP" which performs various mathematical manipulations on now digitized signal.  Instead of a PC which is used by the SDR-1000 to work the DSP and control magic the KX3 uses a Analogue device ADSP21479 DSP chip.  I reviewed the specs of this chip and it's pretty impressive.  Basically this chip replaces the "sound card" which was used by the SDR-1000.  Instead of a PC the KX3 uses a pic18f87k22 8 bit PIC micro-controller for control.  This is a good choice because it's easy on the batteries, and that is one good thing, the KX3 doesn't sip much power on RX.. useful in case of hurricanes!

One feature which severely hobbles the radio is the lack of a panadapter.  The radio is one dimensional.  It basically works like any other legacy radio.  I guess to some that might be an advantage but I didn't care for it.  To get a panadapter working you either have to buy an additional piece of hardware PX3 or a soundcard and additional software and a laptop or other computer.  Or you can build a microcomputer/soundcard/screen outboard panadapter using a beagle bone black or raspberry pi computer   In other words a lot of messing around to get what a Apache Lab Anan 10E does naturally for less money


I own the Anan-10 version of this radio and IMHO it is a far better choice than the KX3 UNLESS your goal is QRP in the woods, a hurricane, or something like that.  The KX3 will run for a LONG time on a battery.  The Anan-10 requires more power and a laptop as its minimal configuration but it is not at all out of the realm of a solar based power system.

The KX3 receiver is very good but not amazing as it is often touted to me.  It is no more amazing than the SDR-1000 was in it's heyday in fact not as good.

Here are the KX3 specs from Sherwood's site


Note it says 65 dB dynamic range   Here is what "v" says


All of these radios are phasing radios.  What that means is their dynamic range is limited by the ability to null out the image.  Flex in the SDR-1000 days created a routine that dynamically nulled out the image in the background in real time.  It was an amazing feat.  The image null degrades as you change bands and change frequencies.  You have to null the image very close to the freq where you are operating to get best performance.  The inability to null is a definite disadvantage and is probably why the optional "filter" is recommended since it is likely the PIC is not quite up to the task of dynamic nulling like the old SDR-1000.  None the less the comments about the radio being the "best receiver I ever owned" are undoubtedly true!  I said the same thing when I bought my SDR-1000 and sold my Orion and FT-1000D.  As long as they don't overload SDR's are amazing.  

I played with the built in decoders for RTTY, PSK and CW.  Seemed to me these were very high maintenance compared to a program like WinWarbler or CW skimmer and they didn't work very well but they did work.  If my goal was digital in the wild I would definitely be looking at the Anan 10 or 10E, plus maybe a Elecraft T-1 tuner.  

So for me owning this radio is a mixed bag.  I do not like the fact Elecraft charges you an arm and a leg for every extra cable and screw, like $30 for a mini manual or $30 for a USB cord which is required to update the firmware.  I do not like the fact you have to
 add a bunch of extra stuff to even approach something like the Anan 10E in terms of the real SDR experience (2 or 3 dimensions instead of 1).  I like it's portability.  I like its receiver and transmitter.  Mine has the built in antenna tuner which is yet another accessory t o pay for and I really like that!  I like how it operates on CW, but the old K-1 was very good on CW as well.  I'm not much on the batteries being built in or the dorky little paddle on the front or the fact that if you are going to operate digital at full power you need add on heat sinks, because if you get the radio too hot the power cuts back.  You can run the 10 at full power all day and it will continue to run at full power.  I don't care for the BNC sticking out of the side.  What can I say: it is what it is and it ain't what it ain't

73  W9OY


Tuesday, May 19, 2015

Remote Operation

With all the Hubbub over Maestro I decided to set up my radios on my LAN network.  I wanted to give remote ops a whirl and see how all the hard work that went into this design paid off.  My shack is at the farthest point you can get from my WIFI router.  I have had at best fair to poor luck with the WIFI.  There is a story about 2 guys sitting on a porch with an old hound dog.  Every so often the dog would howl.  The man asked the owner why that dog was howling.  The owner said he's laying on a nail.  The man asked why doesn't he move?  The owner said it doesn't hurt enough yet!  Well tonight it hurt enough for me.

My house doesn't lend itself to stringing wire, but I figured out a scheme that hid the wire for the most part.  I ran it out of the wall and was able to tuck it into soffit and then into the garage attic where I could send it into the shack.  Worked great!  Here is the new topology of Flex aspect of my LAN

I of course have a million other things connected but from a FlexNet perspective I have 2 radios and a computer connected to a 5 port switch which then connects to the router via my new cable.  I have outstanding speed on this.  I was concerned the radios would not be correctly identified by the router but the DCHP picked them right up.  Now when I connect to a radio I get this startup screen


I choose the 6500 in the shack on the shack computer and it fired right up and I could identify both radio's IP address in the router set up.  The point of all this is to demonstrate how well behaved the networking is with the Flex radios.  

I next downloaded 1.4.11 onto a remote wifi based computer.  



I opened the 6300


And away we go!  It was literally that easy.  I next tuned up the antenna using the tuner and tried a short tune


Excellent!



Here is a shot of the tune power and SWR.  Everything worked.  I could change mode, adjust bandwidth send CW with the keyboard etc etc 

Here is a short video of me working my 6300 via wifi remote on my LAN.  It took twice as long to write this as it did to get it running



73  W9OY


6M Season is Upon Us


I was fooling around in the shack and noticed the above in DXLab's DXview map.  The short black lines means VHF/UHF is active!


I reconfigured the 6500 for 6M mode.  I usually open 2 panadapters.  The lower pan shows a wide swath of the band.  I can see SSB CW and beacons on this pan.  The upper pan is for QSOs.  


I have skimmer hooked up so I can rapidly scan where the opening is, although down here in FL many of the local stations sport callsigns from northern states (yours truly included).  SmartSDR has a built in keyboard/paddle/memory keyer so I filled out the memories for a typical 6M CW exchange and proceeded to knock off a dozen contacts mostly from PA NY and VE3.  There was also some SSB activity but I didn't listen in.  My antennas on 6 are horrible.  I use a 80M vertical or a W5GI version of a G5RV.  I normally tune with a MFJ-998 tuner, but since I don't run any power beside the exciter I decided to use the built in tuner on the 6500.  The MFJ cranks and cranks to find a match but the Flex tuner found a match in three clicks.


In the last software release Flex redesigned the Tuner to include multiple memories which also include remembering tuning solutions for multiple antennas.  So if you are on 6 and have one antenna on ANT1 and a second on ANT2, when you switch antennas the correct tuning solution is remembered for each port/antenna.  Very handy.  This is also the case for other bands so if you set up some tuning solutions for lets say XX.025MHZ of every CW portion of every band the tuner will recall the correct solution for a given antenna port with no need to retune.  Ideal if you run a contest barefoot with a multiband antenna for example.  Click and go!

I recently added a ALA100M loop antenna from Wellbrook.  I have the masthead preamp connected to a 23ft circumference loop up 25ft in a corner of the back yard.


This thing works very well on 6M.  I'm pleasantly surprised.  Looking forward to more openings this season

73  W9OY


Thursday, May 14, 2015

Global AIS on SPACE STATION and the Flex 6700R

World wide commercial ships have a problem, soon enough they are out of range of communication.  Ships these days have a AIS or automatic identification system but they system looses its link to shore with in 30 to 60 miles.  Glass is a proposed system which uses the AIS system to talk to the International Space Station.

The ISS traces a path over nearly the entire earth as it flies 400km above the earth traveling at 7.7 km/s.. that covers a lot of surface very routinely.


GLASS proposes to turn the ISS into a LEO that uploads packet data as it traverses over head.  Shades of OSCAR from decades past!  Data could include telemetry such as position and weather for example.  So as ships float around various regions reams of usable data can be obtained and analyzed.  Here is a slide show presented by Steve N5AC regarding this project  At the end I will mention  Flex Radio's involvement in this project and the value design features like the API's hold.  









So here you go.  Our radio or at least the RX version of the radio is hardened enough, reliable enough, and versatile enough to take on a space project.  


Using the very same interfaces especially Waveforms that we use this radio become the center of this data system store and forward experiment.  You read my thoughts of how amazing I think this method of turning the Flex's infrastructure into an experimenter's sand box and here is the proof of how this infrastructure can push the envelop of science and communications.  This is what ham radio was about when I first got into it 52 years ago.  I recently read a forum post describing the Flex line as the arm chair operator's SDR while the Anan crowd was the real experimenter crowd.  Read this presentation and you get a clue about who the real experimenters are.  No company in ham radio has this kind of capability off the shelf.  No company in ham radio has this kind of far reaching insight, to create a infrastructure that so easily allows these ideas to be created.   

Friday, May 8, 2015

Free DV

Flex has developed a second API which allows inclusion of new modes and other "waveforms" modules into the radio.  With the latest Apha release a codec (called codec2) has been included that allows Free DV QSO's to be made.  No need to go through the pain of configuring sound cards etc you simply add the codec to the waveform library, start the little app and you are on Free DV.



What is Free DV?   Here is a quote from the Flex Alpha Test Waveform Manual :

"The first WAVEFORM Module being provided for the FLEX-6000 radio series is the FREEDV/CODEC2 module. FREEDV is a free, open source, digital voice communications system for HF amateur radio, which uses the CODEC2 low bit rate VOCODER (Voice Coder Decoder) developed by David Rowe, VK5DGR. A FREEDV signal only occupies one half the bandwidth of a normal SSB signal. It may be installed in any FLEX-6000 Signature Series radio by using the instructions below. Once installed, the ability to transmit and receive using FREEDV/CODEC2 is added to the FLEX-6000 radio, and a new mode button named “FDV” appears alongside USB, LSB, FM, etc. If you press this button, the radio talks and listens in this new narrowband digital voice mode. Future WAVEFORM Modules may be implemented for signaling and digital modes such as RTTY and PSK-31 extending the capability of the radio. WAVEFORM Modules also allow a user with appropriate programming skills to add modes or functionality to the FLEX-6000 radio, by using a defined, open, API (Application Programming Interface)."

How do you install the codec?  You download the codec from the author (in this case Flex) open the waveforms choice in the menu


and Install


The codec is integrated into the radio.  You click on FDV and start having QSO's


It's that simple and that powerful.  

Free DV is a version of QPSK, kind of a cross between PSK and DSL  16 packet streams are generated and the voice compressed down to 1.25 khz is spread across these 16 channels for transmission  


It is then received and decoded and the voice signal is then reconstructed.  Voice can be reliably decoded down to a signal to noise of 2 dB.  There is no static or background noise, it sounds like you are talking to someone in the room.  It also has a text channel 


This was copied off of my 6300 pan adapter!  How cool!  Here lives the free DV home page  For us we just include the codec in the radio click a mode choice.  For the rest of Ham-manity you have to configure the software, screw around with sound cards and interfaces and separate mics and headphones etc.  

There is a web page which lists people that are listening and where they are listening

There are freqs available on every HF band but so far 20M is he only place I've seen any activity.  Not bad, half the bandwidth, no splatter, no static, fairly immune to interference, armchair copy, FREE as in Free DV!  Also free as in speech  You can hear snippets and learn more about codec 2 here 

You hear people go on and on about how Flex has closed its software.   Does this look closed to you?  It's friggin wide open and totally available to developers.  Here is how open the API is.  There are several clients written by private developers that are in widespread use with Flex users.  DDUTIL by K5FR, SDR-Bridge by W2RF and FDStack by MKCM software are in use at my station.  After integrating the FreeDV codec, I used the memory function in DDUTIL to store a FDV freq  The freq shows up totally integrated in DDUTIL  


Note how the mode lists FDV in the memory slot.  If I'm on 40 CW and click load I'm immediately taken to 20M FDV with all parameters preset.  FRStack is a memory matrix program which copies data out of the SSDR memory stack.  This is a snapshot of the last 4 freqs I've been on on every band.  Some of these are weeks old some are real time it just depends where the radio has been and when.


You can see SW and MW as well as Ham listed in the table.  I can promote a listing to a stable memory with a click and that creates a new table on another tab  and allows me to store and label memories on all band including non ham bands


When I store a FDV freq it is stored as FDV


With all the appropriate parameters.  For example I use a loop antenna on RX which comes in on the XVTR port and another antenna on ANT1 for transmitting.  This is all saved.  Nothing was done to these external programs to make them talk to the FreeDV codec, FreeDV simply integrated itself as part of the ecosystem.  Imagine someone writes a waveform codec that decodes PSK and displays it as an overlay on the panadapter or some other more exotic idea.  This can therefore be directly integrated into the radio and if there is some special flyout form (like a special control panel) associated with this codec that can be directly integrated into the rest of the ecosystem.  

This is what separates Flex.  They take a goal and break it down to its basic infrastructure and then build that (in this case the waveforms infrastructure)  It includes all the necessary things needed to integrate into the radio.  They then publish the API and will release the ability to write code and experiment and improve the radio.  So if your goal is to improve the radio or push the state of the art Flex has your back.  They did something similar with the release of REMOTE.  You can make your radio remote on your LAN in 10 minutes.  Flex created the infrastructure.  Soon enough WAN remote base should be available to all users...and so on and so on.

Here is a clip from a FreeDV QSO on 20M




73  W9OY








Saturday, May 2, 2015

Anan 10 again


Anan 10

I bought a Flex 6500 which has yet to arrive and thought I would liquidate some of my SDR stock to defray the cost.  I sold off my Anan 100D, and I had this little gem listed on Swap.QTH.  Between the sales of the two the 6500 would be a wash trade.  I was pretty tired of the 100D.  It's a super radio but I like Flex's approach to SDR better.  I listed the 10 and decided to put it on the air to make sure everything was up to snuff before I let it go.

I had redone my computer with a fresh install of Win8.1 and didn't even have any HPSDR stuff loaded.  I loaded the latest, and a copy of virtual audio cable, set the stuff up and plugged in the radio


Next I rounded out the desktop with a copy of CW skimmer and DDUTil v2.  I use v2 with my Anan stuff   since I use DDUTil v3 with the Flex stuff and I can run both simultaneously if I use 2 different programs.  Supporting programs are Virtual Audio Cable 4.09 from my Flex 5000 days and SmartCat for virtual serial port duties.


My logging/cluster software DXLab can be set up o switch back and forth between my Flex radios and the Anan



BIG MISTAKE!  There were a half dozen contests occupying 15M various QSO parties etc.  I had my LDG Z-11 pro sitting on the shelf so I plugged the Anan into the Z-11 and the W5GI dipole into the Z-11 and hit the tune.  3 watts and 3 seconds later I was 1.3:1.  I set up CWX in HPSDR_mrx for a contest exchange plugged in my custom N3ZN ZN-SL1 paddle and decided to see what a few wattrs could do


Smashing success.  I spent a lot of time looking for other qrp contesters and enjoying the radio.  So I took the add off Swap.QTH.  The Anan 10 weighs 3.3 lbs and with the Z-11 which can be battery powered and a laptop you could very easily head out to the beach or mountaintop for some deluxe DX-ing.  I made a little youtube video of a contact 

 

2 boxes power laptop and a key for this kind of quality SDR experience YES!

73  W9OY