Tuesday, May 24, 2011

PP0T Trinadade & Martin Vaz

This morning I couldn't sleep so I decided to brave the static and flipped on the radio. The static was out of OK and AR this morning

I saw the expedition on Trinidade spotted on 40 and decided to give a listen.

He was in the mud until I got diversity adjusted and then he was Q5 but still with a lot of static and QSB typical of summer time conditions. He was working one-zeez and two-zeez up one mostly EU. Here are the stats and location for Trinadade

It's about 4700 miles SE. Here is a google shot of the island

The pics shot off and around the island are stunning and worth the google trip. A little after I worked him he QRT'd and I was hoping he might show up down on 80M so I hung around for a bit to write this blog post and see what might develop, but no such luck. Trinadade has an interesting history and you can read more on the PP0T web site

There is only one op on this expedition as his transport was a Brazilian Navy ship and it headed out at the end of April to return in June. Pretty exciting to contemplate operating from a place like this for a month or more


Monday, April 25, 2011


I've been off the radio for a few weeks and flipped on 80M and there was FJ/OH2YL Anne is on DX pedition on St Barts operating 160-10 CW

She was an easy chip shot from FL

When I first heard her she was working the gray line across EU and Russia. According to the web site she is running a pair of phased HF-2V butternut verticals. She was probably beaming EU as her strength was such that I probably worked her off the side of her array

She was in direct competition with the storms over Louisiana. The storms are about -95dBm, summer time cdx are certainly here.

I flipped on diversity and was able to null the static down to about -102 dBm making the listening much more pleasant.

I listened to her knock off station after station as I wrote this post. She is one fine operator. Wish she would QSY to 40 :)


Sunday, April 10, 2011

The Amazing World of Ham Radio

So no sooner did I write about the "Knob Project" than did I start to receive email from others who have been involved in developing similar ideas.

James KS4JU editor of HamRadioScience wrote about development of computer cases with built in screens

His comment is that some of these cases also contain remote controllers

I can see the brain flashes going off all over radio land!!!

This morning before I even got my Latte I got a note from Tobias DH1TW about his project

This guy has developed a complete control surface for PSDR using a DJ console that is in Beta testing!!

I haven't had the chance to review either of these developments in detail, but I think its GREAT!! It shows the versitility of a plastic radio, that is a radio that can be molded by the user to fit the user's needs. In my case I wanted a radio station that was highly integrated. I wanted a radio station that would do my will and follow my needs without my having to do much in the way of knob twisting and button pushing. I wanted a radio station with a high degree of efficiency and I had a blast creating that all based around PSDR and DDUTIL. To acheive my goal I needed this

A 19 dollar board from Unified Microsystems and the support of K5FR and DDUTIL

I also wanted to try to bring to ham radio the promise of SO2R based in software as an extension of the automated station, and to a very large extent we have created this also using N1MM as the contest interface.

James is interested in a radio in a box kind of approach YET the radio looses none of its flexibility. It gives up nothing but gains in its individual expression of character. On the other end I have seen PSDR displayed on 40 inch TV screens at the Orlando hamfest

A few of us got together and built a Knob

as a foray into a different means of control for use in contesting and DXing, and the Knob was turned into a commercial product

And now other hams from around the world are revealing their own additions and variations and ingenuity!! What fun this hobby is!!


Friday, April 8, 2011

The Knob becomes a FlexControl

Flex is announcing a commercial version of the Knob by K6TU and K6TD. Here is a recap on Stu's website regarding bringing this product to market

Contest Knob – Announcing the Product

I didn't really have anything to do with bringing this concept to market except for my input in helping design how the Knob does its "Control" thing, which I think it does VERY WELL. For $129.95 the "Flexibility" this device brings to the radio is well worth it. It is much much more than a contest controler, but makes a whole panoply of features readily available to the finger tips.

The argument has always been either/or. EITHER it's point and shoot OR it's a Knob that is needed. This device makes it BOTH/AND since it is seamlessly integrated into the operation of the radio. Its presence brings a whole new level of integration to managing the radio, and in my operation it has become indispensable. It was a lot of fun being involved in this project, and it shows once again the ingenuity of hams in solving their own problems and in coming together to devise a "corporate" solution. Corporate comes from the Latin: corporātus which means to "form into a body" and that is what happened. Many came together to create something useful for all involved.

I haven't had the chance to give the commercial version a whirl, but given what I know of the prototype, I would not hesitate for a second to recommend it to anyone who is interested.


Tuesday, March 29, 2011

More Knob

Origins & Refinement of the Contest Knob - II

Stu continues with part 2 of his recap of the development of this fine contraption. Just for the record I am never satisfied but I am willing to be bounded :)


Sunday, March 27, 2011


I was doing a little correspondence when UN3F in Kazakhstan popped up on 30M. Recently I have increased my 30M operating. I am usually on 40, 80 and 160 and had only worked about 100 countries on 30M till about a month ago, so I have been trying to pick things up on 30 since not too much new in the way of spots comes across the cluster for the other bands. I could do a lot more on 160 but my antennas are still down on that band.

Just as I tuned him in he was working a WB8 and I was getting set to work him and he seemed to disappear, probably going QRT. He was past his sunrise so he was probably heading out to work. At the same time I saw 4K8M in Azerbaijan spotted so I loaded up the memories and had at it, clicking back and forth.

Unfortunately UF3F was truly gone but I had 4k8M in the log first call.

I have 3 antennas available for 30M and none of them are great. I have a 135ft flat top at about 50 ft fed with open wire to a Johnson KW matchbox. That antenna has as pattern that looks like this on 30M (north is strait up)

This antenna was not a very good match for UN3F but a better match for 4K8M

The second antenna is my 65ft 80M vertical. On 30M this antenna approximates a 5/8 wave vertical. This antenna has an extensive radial system and exhibits a SWR of about 2:1 on 30M. I better match that with an Ameritron tuner. This is the antenna I use the most on 30M

Finally I have a 45 ft vertical wire out of a tree that has a MFJ 929 auto tuner at the base of the tree. It has a beautiful pattern:

unfortunately the ground system on this antenna is abysmal since I mostly use it as a RX probe antenna for diversity, so I don't transmit on it much. UN3F is on fairly often so I'm sure I will have another shot at him before summer


Saturday, March 26, 2011


My old buddy K3RR and I were corresponding and he mentioned the difference between his cascaded 250hz filters and my 12hz DSP filters. The theoretical difference is 10log 250/12 =13.2 dBm. I was sitting on 80M seeing if I could hear anything out of A52J:

(after all hope springs eternal) and since the band was so quiet I decided to measure the difference and make a little document.

Here is the radio with 12hz filters:

The RX2 receiver's vertical antenna has a little less output than the full size vertical on 80M connected to RX1. Best case today is in the -118dB range. For the 250hz case:

-107 dBm was the best I could do which is about 11 dBm difference. So the filter difference extends me another 11 dB into the noise floor. I decided to look at 500hz filters as well:

Predicted is 16.2 dBm and I got 14dBm difference, very consistent with the data point above. Some of the difference between predicted and measured could be due to AGC action since certainly by the time I get 16dB above the noise there is some AGC starting to flatten out the signal. I had "best" AGC-T (agc threshold, or the point at which the AGC just starts to reduce gain) set on the 12hz filters:

When I readjusted on the wider filters it didn't make any difference. The AGC-T adjustment is one of the best features of this radio. The AGC is designed to effectively turn down the sensitivity of the radio. If the AGC is not active the radio is most sensitive. By adjusting the AGC-T you can set the AGC to turn on at some point considerably higher than the band noise. This is a big deal when working DX since in most radios the AGC is already well engaged and turning down the sensitivity due to the band noise itself, so you are never really able to realize the full sensitivity of the radio or the full dynamic range. Since you don't need the radio to be more sensitive than band conditions allow by adjusting the AGC-T your chances of hearing someone right at the noise are improved.

Here is a shot at 500hz with the noise blankers turned off


and now at 500hz with the blankers turned on

Without the noise blankers, the AGC-T and the 12hz filters (and diversity) I basically would only be working G's, OK's and DL's on the bands.

Here is a shot of the radio on 10M with a resonant vertical attached

and here is a shot with no antenna connected to RX1

Still no Bhutan but VU4PB just showed up on 40 to tease me:

A nice European pile up and a K1 who is hearing him. It's the K1's gray line time so maybe tonight is the night:


Thursday, March 24, 2011

Debut of the Knob

This is a project that is coming to fruition. It started as the brain child of Stu K6TU. I'm going to spend some time on the history and development of this project because I think it is a very interesting story. What it shows is how some people who don't know each other or know each other loosely, and who are scattered across the USA can come together around an idea and make it into a reality. Its a story also about a company Flex Radio who allowed for its software to be modified through the exposure of new CAT commands in PSDR so that this Knob could come to fruition. I asked Stu for some background and he published:

Origins & Refinement of the Contest Knob – I

I will follow with some more of Stu's history as it is published. What you see pictured above is the end product of this project. Once Stu K6Tu and Kevin K6TD had a design it was forwarded to Steve K5FR. Steve made up 5 prototypes. It was about this time Steve and I were hot and heavy into creating the SO2R interface using N1MM. I was totally unaware of the Knob development. A bit later I received a copy from Steve. Steve wrote the interface which now appears in DDUTIL and it allows the Knob to control PSDR

Stu is a master of PIC micro-controller code. A PIC chip (short for Peripheral Interface Controller) is a device which can be programmed to read inputs from the world outside itself, do some processing on the data it receives, and then output the results of its processing. Here is a short tutorial on how a PIC works

What was created was a USB based Knob controler for PSDR that could send up and down signals to DDUTIL as it was turned. The Knob also has a switch connected to it, like a big push button. In addition 3 more switches and some LEDs were added to the mix. The PIC scans its inputs and looks for state changes for example a knob twist. The knob when its twisted causes a series of signals to be sent to the PIC like the dits of a Keyer. If you twist a lot you generate a bunch of "dits" if you twist only a tiny bit only one "dit" gets sent. The PIC can also tell direction If you twist CW the function being controlled goes up and if you twist CCW it goes down. The most obvious thing to control is a VFO but the knob can also control things like audio gain and RIT and XIT. The button on the knob can control various functions for example if you push once you can toggle between VFO A and VFO B.

Stu put in a feature that allows for the Knob button to control up to three functions and and to be able to toggle between 2 banks of functions The original code Knob code only had three functions for the buttons, but at my request Stu recoded the firmare to include 9 total functions for the 3 buttons. Here is a shot of the DDUTIL interface

The 6 boxes grouped together are Knob click controls. Off and Sgl-clk are a toggle pair short click once and VFO A switches to VFO B. Short click again and you're back at VFO A. If you double click you will turn on and off variable tuning which is an acceleration feature of the knob. If you twist fast the software recognizes that and will move faster in the direction of twist. This way you can cover a lot of ground with a twist. If you then light on a station where you want fine control the software automatically decelerates and you get very fine control.

One of the commands we had to be able to access was the ability to tune the TX VFO when in diversity mode

Bob K5KDN at Flex created for us a means in PSDR to do that using CAT commands

If I LONG click the knob the B row of functions is activated

and I can once again do the various toggles I described on a second bank of commands. Here is a drop down of some of the commands available on the Knob button

All button presses are not created equal however and Dbl-Clk has some unique choices

Now comes the 3 buttons on the top of the box.

As you can see each of these also have the ability to control 3 different commands

and the command choices is pretty extensive

We included up to 8 Macro commands so the real functionality extends to the entire CAT set of PSDR which is close to 150 commands. In addition you can do complex commands in the macros like one button press for diversity on or off.

Here is a shot of my macro file for the Knob macros:

What the first 3 macros do is address memory 2, memory 3, and memory 4 in CWX

This turns my knob into a memory keyer for working DX!! The first three buttons are now all I need to break pileups and work the DX! In addition the knob does NOT need to be in windows focus to work its magic!

CWX is in need of some serious redesign, but Flex did some improvements in the TX/RX turnaround time and it now works in a fashion capable of breaking a pileup. I now have a memory keyer with basic functionality and push-buttons instead of mouse clicks! I HOPE someday they will tie the speed control to the front panel speed control so you don't have to adjust 2 boxes to change speeds as often happens when there is low band static and the DX is having a bit of a hard time decoding your signal. I would also like at some point the typical functions of a contest keyer.

Since the Knob is independent of the Windows focus, I can be in a logging program or a contest program and still control PSDR from the knob.

The last 2 macros allow me to change step size between 1hz and 100hz. I use 1hz to fine tune in a DX station, and then I switch to VFO TX and use 100hz to quickly cruise up and down the pileup, and I can do all of this without PSDR or DDUTIL being in focus

If I get confused as to what click switch does what, Steve created a little sub window as a guide and it is always visible. (I can not tell you how responsive K5FR was to the development of this control device. The guy is simply amazing)

It shows what VFO bank is active

and it also can memorize a custom label, so W9OY is displayed in the first button instead of Macro M30

Here is what it looks like on my desktop

This project was a blast to participate in. Four guys widely separated across the country from California to Texas to Florida, with widely disparate skills, came together and made it happen. Basically I didn't know Stu or Kevin at all. I knew Steve from other projects we had worked on. I was a late comer to the party give credit to the others primarily, but I did have considerable input in the Knobs final behavior. Thanks also to Flex for exposing the CAT commands we needed to make it happen. The development is ongoing and I will update as time goes on and more becomes available.

This is the reason I wanted take a little time and look at all the means there are to control the Flex Radio. To recap we have all the internal means to control the radio. Then there is CAT as demonstrated through Skimmer. Then there is the effectiveness of this external control on the overall behavior of a radio station By judicious design you can make the F5K and DDUTIL control central for a very complex radio station yet make the station behaveior effortless to use. Then there is further integration with other programs There are improvements and streamlining that improves productivity. Finally there is the Knob, which is a piece of hardware controlled by firmware and provides a windows focus free means to manipulate PSDR. All of this is tied together by K5FR's mighty DDUTIL.

Frank AB2KT, the developer of DttSP used to talk about using a midi surface to control the radio. That concept never really appealed to me because of the ergonomics of a midi surface and a keyboard and a paddle and a mouse and a MIC all spread out over the operating table, but this little knob is totally functional and takes up little room and it is also totally plastic (in terms of being programmable). Change the firmware or the software and voila' new things can happen. Maybe if we do two button pushes together we could get another 9 functions.... Naw Steve and Stu would kill me....