Sunday, November 29, 2009

Sometimes it's what you can't hear that's important

When I get bored with contesting I often try to find "feats of radio magic". I try to find situations that are almost untenable to work in. One year in a 160 contest with my SDR-1000 I was able to separate 2 DX stations into single signals. The DX stations were in different parts of the world both being called by US stations. I worked each station as a single signal and the stations were only 40HZ apart!! 20 is often considered a band that separates the men from the boys. Lots of big signals big beams and high power bullys. I was tuning 20M this afternoon, and here is one I found:

If you look closely at this pic you will see super contest station W0AIH, a little below is LU8YE, a little below that is the green arrow of where my RX"s are tuned and a little below that is W1EM working K2TV, The signal you see is W1EM. The band width is about 1khz total and notice the clickiness of the 2 US stations. The effective band width between W0AIH and W1EM is about 600hz and between LU8YE and W0AIH is less than 100hz. In fact sometimes Lu8YE was inside of W0AIH's bandwidth

Note the S meter readings on both of my receivers. RX 1 is connected to a 55ft high 136ft long flat top fed with open wire and a Johnson KW Matchbox. RX 2 is fed with a resonant 5/8 wave 20M vertical about 150ft south of the flat top. I made a recording of what this sounded like when this picture was being shot

Green Arrow

What you hear is basically nothing, except a tiny bit of backgroud noise. No beeps no boops no clix. My noise floor is -119 dBm on RX1 (flat top) and -125dBm on RX2 (vert)

Next I tuned to LU8YE and made a recording of his signal between these two loud clicky stations.


You easily copy the Argentinian station Q5 as a single signal even with the very loud W0 super contest station blasting along less than 100hz above.

All of this with dozens of other loud US stations all around.

Once again it becomes so obvious how well this RX performs.


Saturday, November 28, 2009

More Diversity

Here is P49V in the contest:

Note I have some local broadband noise on the low end of 20. You can see it on Skimmer. It looks like P49V and the rest are in a snow storm. Down in FL we have a phenomena that I haven't seen any where else. It can literally rain across the street (300ft or so away) and not be raining where you are standing. If you look at the top of the skimmer screem you can almost see this phenomena HK3UA is in the clear. With the present version of the diversity control you can null out the noise and usually find a spot that peaks the signal at the same time. Here is a shot of the noise nulled out:

If you look at the top panadapter you can see I gain a good 15dBm of signal to noise. I didn't notch for max signal to noise, I notched for best signal to noise while improving P49V's relative signal strength in my headphones.

Here is an audio clip of what this all sounds like. The signal starts out in the noise then I switch diversity on then off then on


I have more fun that should be allowed with this radio


I never get on 10M

I haven't been on 10M in years. With the contest I decided to see what I could see. I don't have a beam, but I do have 136ft of open wire fed dipole up about 55 ft and I loaded that up with the Johnson Matchbox. Imagine my surprise at a band full of DX. Imagine my surprise also at my band noise, -142dBm Amazing

73 W9OY

Friday, November 27, 2009

Band O' RF

I was playing around in CQWW. I thought it might be interesting to see why contests are so challenging to a receiver. I turned off the click filter in Skimmer so you can see the wall of crap that is being generated

It is often "presumed" by the K3 crowd that the Flex radios can't possibly stand up to this, that some how the RX will fold. Nothing could be further from the truth. In this sea of high power and clix my noise level is about -116 tonight and I have no trouble hearing stations at the noise. No beeps no boops no overload, just good clean CW. I'll let them have their delusion and instead I'll just work the DX

Back to the war


Wednesday, November 25, 2009

Betty meet Diversity...Diversity....Betty

Flex has been hard at implementing something called PAL or platform abstraction layer into PowerSDR. This is a step toward making the software platform (as in operating system) independent. What that means is that the software can be configured to work on MAC and Linux and other O/S's besides Windows. I have not really been involved in this aspect of the development until last night. Last night I updated my program to work with the PAL subversion. I downloaded the files from one of Bob N4HY's folders on the Flex sub-versioning (SVN) server. The SVN is where many different versions of the software reside as they are being developed. I opened up the version contained in this folder and here is the console that greeted me

This is the new "Pretty Betty" console. At present there are 11 different console variations living in this sub-version that I can choose from. This one is called "default". Various aspects of this console are also adjustable so you can further modify the appearance in literally hundreds of ways. In my operation I tend to upgrade things a lot and I want to spend as little time as possible customizing things since it doesn't really matter to me, but for a guy say with color blindness or in need of high contrast in visual perspectives, this would be a Godsend, PLUS it just looks cool!!

I was yanking around on Betty and hit ALt-Ctl-R and up popped my old friend Diversity

Many of the bugs of the early alpha version of the code have been squished and the console now allows diversity to be easily integrated into the operations. This is a shot of A31A on 40M this morning. He was zero copy without diversity. My night time/early morning noise has lately become horrible. There is something in the neighborhood that has arrived to screw up my ham radio fun. It adds about 15 or 20 dB to my noise floor. I may have to go around and shoot out all the street lights since it seems to adhere to this kind of timing pattern. In the mean time diversity may assist me in my woe.

There are still some bugs to squish, so its time to get out the hammer and see how many ways I can break the software, but that's what I do best :) If you have an interest I suggest you give Betty and Diversity a whirl they are becoming the premier pair.

To run this you need the latest driver


and the latest firmware


from the Flex website download page and the SVN address for the relaease is


PLUS PLUS PLUS add this .dll file into the folder where you copy the above files

HOT DOG I got Diversity back just in time for CQWW CW!!!!!! And Betty is easy on the eyes!

You see it's proof: God loves me and He wants me to be happy :)

For grins I heard 3V3S in Tunsia on 30M so I fired up diversity and bagged him in 3 calls


Monday, November 23, 2009


Just nailed VK9XX on Christmas Island on 40 AND 80. I've been listening to him build on 40 for an hour and even turned on the Acom 2000A to get that last couple of dB. If you look at the pileup on the panadapter it shows a pretty remarkable splotch of RF. He was tuning all over the pileup and I basically put myself in his path based on the last 599 on skimmer and my perceived sense of his next direction. This radio is so much fun to DX with. It seems Skimmer is catching on with the DX crowd as I could see the pileup build around the last 599 as he moved up and down the pile. The NAY sayers complain and bitch about skimmer, but I bet every one of them that can run skimmer IS running skimmer because of the advantage it gives you in pileup analysis. The days of Bob Locker W9KNI and his starting at the bottom of the band and tuning to the top are history as far as I'm concerned.

Here is a shot of the path from FL this time of day. Note I am still in daylight and his daylight is still approaching:

I've been struggling lately with excess noise in my neighborhood as well as some lightning problems especially out in Texas and the Atlantic. Usually by now lightening has quieted down enough to become a non problem but not this year. Even so the bands have been remarkable with all the DX available this year especially on 80 and 40M

I no sooner got him in the log on 40 and started this blog entry than he came up on 80:

I switched the antenna to 80 and touched the paddle and the ACOM tune immediately to 80. There were almost no stations calling at this point so I had to figure out the split. It was a little under 2khz A couple calls and he was in the log on 80 as well. Here was the path at QSO time

The perfect gray line shot!!

My other project lately is to rebuild the control head of my Ameritron RCS4 antenna switch so it can become a random access remote control antenna switch run by my F5K using DDUTIL. The RCS4 is a cleaver switch that sends control voltages down the coax so you don't have to run extra control cables. It has 4 positions that are controlled with a + voltage, a - voltage, an AC voltage, and no voltage. The problem is the voltages can not be effectively managed randomly they have to be chosen in a sequential fashion or the PS shorts out and blows the fuse. I figured out a way to make this work and now its time to get some hardware to bring my idea to fruition.

DDUTIL has all the band following capability I need in a BCD format that is displayed on a LPT port. Now the rub. My new computer has NO LPT port and no header or any hardware on the MB. What's a mother to do?

I thought I would just be able to use a USB to "LPT" adapter but in fact those ports enumerate as LPT under Ports in windows but as "windows printing" under USB. Fortunately Joe Levy turned me on to this site:

and I ordered a couple of the V 1.7 kits to give this device a whirl. When the kits arrives I will see how they performs and let you all know. It looks very interesting as it is made to allow up to a 20 pin I/O device. I'm going to try and work with Steve K5FR the creator of DDUTIL and see if I can get this bugger working as it would be a nice addition to the Swiss army knife of a program called DDUTIL

Finally here is a shot of the VK9XX pileup on Christmas and the 9V1YC pileup in Singapore just above:

How much fun can you have?

Stay Tuned :)


Monday, November 16, 2009

Upgrading My LP-100

I own 2 of these meters. They are the LP-100 Digital vector wattmeters by N8LP. I was an early adopter, having built my first meter in 2006 when they first came out. My serial number is in the low 100's. I was so happy with this meter I bought a second one a few months later, as I routinely run 2 "stations" simultaneously, one for ragchewing and one so that I can chase DX while I am ragchewing. That means 2 amps and 2 sets of antennas so I wanted 2 meters in the line.

These meters are calibrated with a know traceable NIST source and are accurate to within about 2% or better across the range from 50 mW to 3000W They also measure phase and resistance as well as SWR and can be used as a highly accurate field strength meter.

These meters have performed flawlessly for that past 3 years, EXCEPT they had a PLED display and PLED displays have a problem, they wear out if you leave them on. Larry N8LP solved this by upgrading the LP_100 to the LP-100A. Most manufacturers would just let you eat the obsolescence. You would get the "sorry we don't carry that part anymore" routine. Larry OTOH designed a conversion kit to renew the LP-100 and convert it to a fully functional LP-100A. This is the delight of software defined products that you can easily extend their lives to match current production products

The upgrade consisted of installing a daughter card which contains the original micro-controller a driver for the new display and the new display

There are several options of assembly from a kit format to sending the unit back to Larry for factory intallation. I chose the kit route. Assembly and installation was trivial. I installed the new components and uploaded the firmware and I was back on the air with a pretty new robin's egg blue display!!

The latest version of this meter includes a dual coupler option which allows 2 signal paths to be displayed on one meter Larry has a vast array of accessories for various ham radio products as well as his spiffy watt meters. The watt meter is a virtual transmitting VNA capable of sweeping antennas for SWR and impedance information using a radio like the F5K which can become a software controlled freq generator. It also can be used to plot antenna pattern information using a radio like the F5K Check out the LP-100 and Larry's other brainy creations at


Friday, November 13, 2009

An interesting conundrum

This morning I was tuning 160. XR0Y was on 1823 working a pileup UP 1.5 khz. TX3A was on 1830.7 working a pileup DOWN 5 khz. This basically means the actual pile ups were on top of each other!!!

This presents an interesting problem. What happens if you dump it in on say 1825 and you are listening on 1823 and the guy up on 1830.7 answers you? Do you miss the contact? Not with the F5K you don't

You just do an ALT-CLT D with the keyboard and you are in TRIPLEX mode. You set RX A to 1830.7 and RX B to 1823 and the TX to 1825. Then after you transmit, you can listen for replies from BOTH stations and just work whomever answers you!!! HIram Percy give you lemons? Make Lemonade :)

Way Too Cool


Tuesday, November 10, 2009


I was lurking around hoping to hear TX3A on some band beside 160. I've heard them on 80 once. As I was tuning 40 I saw this. The DX has the green arrow on his signal. Those callsigns show the limitations of skimmer as they are not CW stations and that 599 is not a 599 but merely what skimmer "copies". Its brains are not perfect but what it it displays for my analysis is super interesting. More on that as we proceed

This is a RTTY pileup on XR0Y down on Easter Island. I don't have any digital software hooked up at present but I thought it was interesting to see a RTTY pileup. I continued to tune around and eventually wound back up on 40 and this is what I saw

If you look at the signal below the green arrow you will see the mark and the space signal of XR0Y and in between the mark and the space there is a signal that looks like a check mark. This is what a signal looks like when it has chirp. This was a PU station having a QSO in between the mark and the space of the XR0 station!! He was running about s-4 (-107dBm or so). He was perfectly Q5 between the mark and the space. I had my filters set to 25hz. I have taken to just running 25hz all the time in the past few months. Between skimmer and the F5K it is a one click maneuver to get precisely on freq so even this bandwidth is no problem to tune.

Here is a closer look at this situation

I didn't make a recording, but this guy sounds like about half of the Cubans you have worked. This is what that sound looks like on Skimmer. Sometimes you get a double curly one down and one up so the element looks like ~

I worked ZL1AZE using 100W up on 80 while tuning around. He was very easy copy so the band should be well open to the TX3 on Chesterfield Is. They must be out for a nice leisurely dinner or making a beer run out to the boat, because the gray line flew over their heads 45 minutes ago and I don't see a peep on any band and people on the cluster are begging them to get on the air. Well I can grab another hour of zzz time so I guess I'll sign off for now....

As if on cue there he was on 3521 very Q5. He was running Japanese stations. Once I figured out his split, he was in the log. I would still like to pick him up on 40 sometime, but I guess he will be there till December

One last horrifying screen shot

This is a shot from skimmer with the click filter turned off. This is what our "modern" transceivers look like on CW Broad as a barn door. The above RTTY shots and the shot of the PU station were also taken with the click filter OFF. Next time you look down your nose at some poor joker out in the Brazilian bush with his chirpy little signal you might wonder exactly what kind of signal YOU are putting out.


Wednesday, November 4, 2009


Mucho 160M big iron rolled out of bed early this morning to work TX3A. I could just hear due to low noise conditions here in FL (FINALLY!!!!!). Here is Chesterton on a map

I'm the little black dot in FL He is the little blue dot off east Australia. We usually have pretty good propagation to Australia so this might be do-able for me. If I had some gray line time this morning it might be do-able, as he is building nicely but alas I have to go.

In the mean time I worked KH2L in Guam up on 40. He was LOUD LOUD LOUD Here is a map of Guam for comparison:

You can see him a thousand miles up the ocean. Did I say he was loud?

Good times