I am experimenting once again with using a computer, its sound card and MixW to perform some RTTY, PSK and other digital modes. Somewhere I have a transformer isolated homebrew adapter made up, but have been examining what new possibilities are offered by my new Icom IC-746.

So I am in the usual evaluation of buy vs. build an adapter. I like to build my adapters, but realize the commercial offerings range from almost too cheap to very expensive.

Being a ham radio operator sometimes forces us to operate from many different locations. We frequently wind up logging our contacts on many different computers. Later we find ourselves with the task of combining our logs into one big log so we can check our standings of whatever it might be we care about: WAS, WAZ, etc.

Over the years I have settled on a method which seems to work quite well. Instead of logging to different files on each computer, I “move” the active log file from one computer to the next using CVS as an intermediate data storage point.

For those not familiar with CVS, it is a software revision control and management system which provides a central organized spot where many developers can work on files separately, but in a controlled fashion which benefits all.

I finally got my copper pipe J-Pole up on a modest mount and cabled into my ham shack. It works, but I stumbled into many interesting things that most folks seem to ignore. In addition to the many J-Pole tutorials on the Internet you should also consider:

Here is a great tool for RF Analysis which:

  • Deals with diffraction effects,
  • Computes the Fresnel effects,
  • Handles elevation data from many different sources

RF Links have many issues that plaque all too many folks in charge of ensuring radios work as planned. A tool like this provides this kind of view…

radiomobile.png

With this tool you can understand why some RF links actually fade even when the two antennas are in complete view of each other. When the wavelengths get longer than light wild things happen. The program is free and, from what I can tell so far, works very well.

In the past few months I have been testing antennas and antenna ground systems for a series of articles on the main part of this web site…

http://www.cosjwt.com/

One piece of equipment which proved absolutely essential is the antenna analyzer from MFJ Enterprises. I have the older cousin of the MFJ-259B pictured here…

mfj-259b.jpg

When feeding a J-Pole is obviously makes sense to install a choke balun to ensure the outside of the coax shield does not conduct energy down the coax thus degrading the antenna pattern via additional radiator area. This article nicely discusses using beads to achieve the goal:

Recently I specified some cables and connectors for an antenna system we are putting together at work. I stumbled across this…

http://www.eham.net/articles/5300

There are some good thoughts in there and, quite obviously, some belief systems in place.

For the average ham with max power on HF and something less on bands above 50MHz the following points worth consideration include:

I have been purchasing some used ham radio equipment from Ebay and decided to see what the Kenwood TS-2000 transceivers are going for on the used market. I discovered they are holding their value quite well… a bit too well actually.

During construction of a vertical antenna in my back yard, I wondered if the popular suggestion that ground rods are essential to good RF performance and antenna efficiency even if you have a system of radials was true.

The answer appears to be no. Visit…

http://www.cosjwt.com/index.php?a=21

…for more information.

TenTec Omni VII

A fellow wrote an excellent summary of some possible ways to control a TenTec Omni VII radio from the Internet. Here is the link…