Friday, October 15, 2010

How my station works




I was up early again. I've been having some trouble with shoulder impingement syndrome and the pain sometimes wakes me up. It's hell to get old but it can help the DXCC situation. This morning I was knocking off some of the PJ- stations on different bands. Displayed is my setup on PJ6A. I received an email yesterday from Jeremy KB7QOA who wondered a little about my setup. I realized I haven't spoken much about that lately and I probably have some new readers who are interested. Jeremy has a good old FT-857 now but is interested in SDR, so I thought I might showcase how my SDR setup works for him and for other readers

My station consists of a F5K, a F3K, a ALS-1300 solid state amp and several verticals that are fed from an Ameritron RCS-4 antenna switch which I have modified for automatic antenna selection, a horizontal flat top openwire fed on 80-6M, and two other verticals that are on independent coaxs, one that auto switches between 80 and 40 and one that is a base tuned 45ft wire vertical. You can look at my antenna selection on the above links

The F5K has many antenna ports.


I brought out Ant 1,2,3 and RX1 and RX2 to SO239 barrell connectors on a patch panel, and I can hook up any of my antennas to any of the various ports simply by plugging into the patch panel This allows me for example to quickly set up various antenna combinations for SO2R operation or for diversity reception, or unplug all antennas when a thunder storm is lurking. The antennas are chosen by software i PowerSDR



Here I have the high performance multiband vertical connected to Ant 2 and the 45ft vert to Ant 1. I can remote tune the 45ft vert simply by switching the transmit ant to 1 and sending 10w down the line


This is how I tune this antenna which I primarily use for diversity reception.

My ALS-1300 and modified RCS-4 are connected to my system through this $19 board


from United Microsystems

This allows my amp and antenna to automatically band follow my transceiver. In addition I use the DXlab suite of software and I use CW skimmer.

These programs are all joined together by the mack daddy of utility programs DDUTIL


and by a couple of programs that allow for I/O of audio called Virtual Audio Cable (VAC)


virtual serial port (VSP)


With these programs I can run a PSK31 program for example win warbler directly control my transceiver with out any kind of "wires" between the PSK31 software and the PowerSDR software which is the heart of the Flex radio The above VAC and VSP allow direct control between the 2 programs



I can also run a direct I/Q stream out of PowerSDR using VAC to CW skimmer which is why I have such wide bandwidth in Skimmer. VSP gives frequency control between the 2 programs

So back to the above picture of my station and PJ6A. What I do is click on the station of interest in this case PJ6A in my DX cluster client called Spot Collector on the lower left side of the screen. This loads the callsign into DX view (upper left) which gives the pertinent stats about this station and this region. For example I see PJ6 short path is 1354 miles on a 120 degree path, and the station is marked both short path and long path on the world map from my FL QTH. I can see the terminator and whether its daylight or darkness between us etc.


As you can see I've worked PJ6 on both 80 and 40

In addition PJ6A is loaded into the capture screen of my logbook


with some standard RST numbers If the exchange is not 599 I simply enter the correct exchange before I log the contact I can store other info like name etc and this will come up if I work the station more than once so I can call the fellow by his name

In addition when I hit the callsign my transceiver moves to the correct band and freq, as do my amp and antenna The split is set and I am ready to transmit


If you look at the skimmer part of this picture


There are 2 ways to determine where the DX is listening BEFORE you transmit. One is to copy the callsign if the station he is calling and look for that station in the list. The other is to look for the red 599 If you study these clues you can tell if the DX station is moving up or down the pileup or staying on the same freq. You can immediately tell if he jumps from the top to the bottom of the pileup. You can tell if he is working stations 2 khz ABOVE the main body of the pileup and all the other tricks DX stations do to spread things out and make sense of the mayhem, and you can do this without transmitting. When you do transmit you can target where you will have the highest likelyhood of paydirt. Sometimes this does not work and you just have to bang away with the rest of the crowd but most times you can limit your calls to a very low number of tries and bingo he is in the log.

This is what fascinates me the most about SDR, how it orders the chaos by providing a new depth of information. I call this information 3 dimensional as compared to the old one dimensional method of previous radios. Old radios use first in first out linear tuning PSDR uses point and shoot. You can precisely point your signal where you want it in the band and you don't have to bother tuning up and down. The panadapter is 2 dimensional as opposed to a knob which is one dimensional. The third dimension to making sense of the chaos is the ability to quickly decode the data contained in the pileup as a whole This dimension is the dimension of knowledge. It is a quantum that allows you to place yourself in the chaos based on a high degree of probability and not just blind randomness or guessing

The ibuprophen is finally kicking in so I'm going to try to grab another couple hours sleep Hope you enjoyed a foray into my ham radio world

73