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Contesting Feedback

Column #86 by John, K3WWP - For various reasons, it takes a long time sometimes to deal with feedback I get from these columns. This particular column deals with feedback from a column almost a year and a half old. As mentioned in my last column, all my old columns are available on my web site at http://home.windstream.net/johnshan/ if you want to refresh your mind as to what the column referred to is all about.

From Alan KB7MBI comes this column feedback followed at the end by my further comments, "John, I loved your article in Issue 4/5 2007. I can't agree more with your points. There is this tendency for folks to want "contesting equalizers". It just can't happen. Power out is a very small part of the difference. I loved you using Effective Radiated Power. That coupled with location, location, and location.

One thing QRPers seem to forget is that it is THE OTHER GUY, the fellow on the receiving end that is doing all the work. This is where I think QRP-SENSE comes into play. If you are hard to copy. Keep the transmissions short and sweet. Adjust the speed to the conditions. If your signal is weak and lots of QRN maybe a slower speed might work better for them to copy. Remember with QRN and QSB you can lose a lot of characters and sending slower may help.

Personally I prefer to pick the weakest station and try to have a QSO...truly "working" that station. I would take one weak station contact over a dozen armchair copies.

Here was a posting I made a while back I think that parallels your thoughts, just not as articulately:

1 watt Rule of Thumb? I had some time basking in the hot sun here in Seattle this weekend and mulled over QRP operations. It APPEARS to me that a general equation for success is that the combination of the lobe pattern (and associated gain/ radiation angle) plus ERP (effective radiated power) when it equals about 1 watt generally adds up to successful contacts being made.

What I was getting at is it is important to know the pattern of your antenna on a particular band and generally how efficient your radiating system is (antenna, feedline) can help you plan for a little success. Sure it is always fun to throw caution to the wind and try set ups at random but sometimes you may just want to increase your odds a bit.

But it appeared that many compromise antennas may add up to feedline loss and radiating efficiency to less than half the power you are starting out with and even more as the power level of the battery supply drops.

Setting aside operator skill, that may suggest why a 500mw rig and a 2X gain figure on a beam up 75-100 feet has about the same success as 5 watts with an inefficient antenna (25 percent).

If this is valid then knowing the general lobe pattern and expected gain figures and estimating the losses are important. It may be a reason why using lossy feedline or an ineffecient short vertical set up and using 5 watts is not that important under many conditions as putting up a FIELD DAY SPECIAL with a little gain and using the QRPp milliwatt radio. Sure the propagation and actual location and several other factors have an effect but GENERALLY SPEAKING it appears from my limited practical experience this holds true.

Nothing magical about the 1 watt other than it being an approximate value. (OK I know someone on 1mw and a bread package wire tirewrap has probably worked DXCC but I am saying under generally average conditions.) Just thought I would pass along for consideration and discussion."

Now my comments. First, it is not the station copying a QRP signal who is totally responsible for the success of a QRP operator. If that were true, anyone at all could get on the air with QRP and be just as successful as someone with a KW/beam station. We know that does not happen. As Alan says, the QRP operator's skill adds a lot to the equation of success.

Alan says sometimes QRS will help under certain conditions. The converse is true also. Sometimes speeding up will help much more, especially when QSB is present. A lot of information can be sent during an upswing in propagation if it is sent at higher speeds. Sending too slow under rapid QSB can cause parts of every word to be lost, whereas with higher speeds, it will be whole words that will be lost. It is easier to figure out missing words most times, than trying to figure out what isolated letters mean. This is especially true in contests, and virtually all top-notch contesters urge QRP ops to send their info as fast as possible. The extreme example of this is meteor-scatter propagation where bursts of CW are machine sent at up to several hundred WPM to take advantage of the extremely short periods of propagation. But that's a whole other field of endeavor.

This is my opinion only, and many do not agree. I know that, so don't bother sending any comments. I feel that using big gain antennas with QRP defeats the entire concept of QRP. Except for the energy savings involved, and that may be important, there is not much difference between running 5 watts and a big high gain antenna than running 100 watts and a dipole. 5 watts into a 13db gain antenna yields an ERP of 100 watts. Is that QRP? Not to my way of thinking. Everything I've accomplished with QRP has been with minimal simple wire antennas, and you can do the same.

Other than that, not much needs to be added to what Alan says. So I'll close for now with an invitation to join the NAQCC as a great adjunct to your FISTS membership. The NAQCC web site is at http://naqcc.info/. Membership is free and there are no obligations other than to help preserve CW on the ham bands in any way you can, especially with all our club activities, all of which are geared to QRP and some in addition to simple wire antennas. 73 till next column. -30-