Friday, January 13, 2012

A, B, C's of Dx Fundamentals of the Art of DXing XV


A, B, C's of Dx Fundamentals of the Art of DXing XV

W5FKX, Don Boudreau

Operating Miscellany

Safe Operating Precautions

There are many aspects of ham radio that can be dangerous if one is not cautious and duly mindful of potential hazards. Above all else, safe operating habits are essential if you want to enjoy the hobby for a long time! Information on safe operating rules and techniques are readily available in books and on the Internet. Here are a few to always keep in mind:

Electrical safety - AC kills! Never underestimate the danger of doing anything out of the ordinary (moving equipment, adjusting interior controls, repairing, etc) with electrically powered equipment when it is connected to the power mains.
Antenna safety - be careful of falling, a common occurrence. Erecting antennas near power lines is to be avoided. Disconnect the antenna from all equipment (especially the transceiver!) before working on it; as an additional precaution, disconnect the transceiver from the AC power lines. To reduce the risk of lightning damage, disconnect antennas when not in use, especially when leaving the premises.
RF safety - RF currents on transmission lines and antennas can be very high and can cause very serious burns and injury, so make certain that your antennas are not within reach by other people or pets. Also, be certain that the RF radiation that you generate does not pose any hazards to tissue damage as a result of over-exposure. Perform an exposure limits analysis after each change in station equipment, configuration, location, or antennas. There are "RF Exposure Calculators" available on the Internet - see references below.

DX activity ranked by entity

What DX can you expect to hear on the bands under usual conditions? Quite a bit, even under less-than-ideal propagation conditions. Of course, the areas of the world that you will most consistently hear on the bands will depend upon your location; for example, Europeans will generally hear a larger selection of "immediate neighbor" DX than do Australians. However, as long as the bands are not completely dead (a relatively rare occasion), one can always expect to hear some DX. The following ranking scale was developed by the author:

Rank
Activity Rating
1 High activity; workable daily
2 Moderate activity; workable monthly
3 Occasional activity; workable annually
4 Low activity; workable within 2 - 5 years
5 Rare activity; DXpedition only; unpredictable

This scale is used to assign an Activity rating to each of the current entities on the annotated "DXCC List" that is provided in the Appendix section. This scale is based upon the current (2006) level of actual activity from each of the DXCC entities, and individual entity ratings may certainly be expected to change in time as a result of changes in the circumstances that influence the level of ham radio activity. Although it is difficult to remove all dependence upon geographic location, and there may be disagreement over some of the assigned ranks, the intent of this system is not to be exact; rather, it is to provide the neophyte DXer with some notion of what to expect while tuning the bands. Based upon this ranking schema, 51 DXCC entities may be expected to be heard almost daily while tuning the bands, while another 92 should be encountered within a month or two. Of course, this does not imply that one should necessarily expect to work DXCC in the first month; however, it does mean that it is possible. Indeed, in the course of any of the several DX contests that are held annually, it is a routine occurrence for DX contesters to work DXCC in a weekend. When I returned to DXing, I spent an enjoyable November weekend in 1989 with the goal of working DXCC and as many of the CQ zones as I could during the CQ WorldWide CW DX contest. With a new transceiver and antenna (a small triband Yagi that I had just put up on a 40 ft crank-up tower), I was able to work 100 entities and 33 of the 40 CQ Zones in 24 hours. This is not meant to be boastful, as many who participate in contests are regularly able to work DXCC+ and all zones over a weekend; rather, it is meant to emphasize the availability of DX on the bands and the value of DX contests for anyone who wants to work new DX.

Band Plans and the IARU

As part of the licensing requirements for all hams, one must learn the spectrum of frequencies in which we are allowed to operate, according to our class of license and mode of operation. The operating frequency bands that the hams in the USA are allowed to use, along with the suggested band-plans for use, can be seen at www.arrl.org/FandES/field/regulations/bandplan.html. During the initial period of start-up activity, a new ham is usually very careful to remain within the prescribed band limits, and rarely tunes elsewhere. It is typically not until later, especially if one becomes interested in chasing DX, that it becomes apparent that there are other hams in other countries that are operating on different frequencies. Why is this?

The answer is that as telecommunications technology developed, its ability to provide political and commercial dividends via broadcast stations quickly made it a prime investment for many. Although by then the ITU (established in 1865) was already providing some international regulation of these activities, the propagation of radio waves at various frequencies was not yet well-understood, nor was the value or the potential growth of the amateur service fully appreciated at the outset of commercial radio. Frequency allocations for broadcast services in one region of the globe overlapped those used by amateurs in others. For example, European, Asian, and some South American AM broadcast stations were often found in the frequency spectrum that was the 40m phone band in North America. Some of these can still be found between 7.150 and 7.200 MHz. Early on, the amateur radio societies that had formed in many countries realized the need to have a voice in addressing these issues of spectral use. In April 1925, radio amateurs from 23 countries in Europe, North and South America, and Japan met in Paris to create the International Amateur Radio Union (IARU) and to adopt a constitution for the purpose of encouraging fraternalism and representing amateur radio at international conferences. It has evolved over the years and is now organized into three Regional Organizations that correspond to the three radio regions of the International Telecommunication Union (ITU), and is recognized by the ITU as spokesman for the Amateur Services.

Currently, there is no worldwide IARU band plan. IARU band plans are adopted at the regional level by the three regional conferences (see link below). However, following a series of meetings that began some years ago, the IARU has successfully achieved one of its prime objectives: an allocation, for amateurs only in the 7 MHz band, of no less than 300 kHz on a world-wide basis.

Pro-signs and Q-Signals

Derived for use in the early days when CW was the primary mode of wireless communication, the pro-signs and international Q-signals that serve as a standardized set of abbreviated words and phrases, as well as a circumvention of language barriers. Considerable information can be exchanged quickly and precisely even between operators with differing languages and alphabets. For example, the following exchange would be readily understood by anyone with basic operating experience:

-------- Exchange --------
------------ Meaning -------------------
QRL? DE W5FKX Is this frequency in use?
CQ DX DE W5FKX K Any DX station please call me now.
VX0DX de W5FKX Establish contact and begin session
RST 479 QRN Nice signal strength but difficult copy due to static interference
PSE QRS Please send more slowly
QTH NEW ORLEANS, LA Location is New Orleans, LA
BTU Back to you
It should be kept in mind that Q-signals were meant to be used as CW shorthand and, unless required because of language issues, are not generally appropriate for voice operation.

A brief, printable list of the most commonly used international Q-signals, along with some of the most commonly encountered abbreviations, is provided here: Qsignals.pdf'. Complete lists of Q-signs and abbreviations are also available at various sites on the internet, notably from the ARRL website (below; although the document is primarily intended as an information reference for use in handling message traffic), and a nice one at the Indiana University ARC website (below) that has audio clips of the signals being sent on CW.

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