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## HF Log Periodic Problem

 Subject: HF Log Periodic Problem k4sb@avana.net (k4sb@avana.net) Tue Oct 15 15:21:33 1996
 ```Let's proceed on one assumption, that the impedence is indeed 105 ohms. Put an electrical quarter wave of 72 ohm coax from the feed of the antenna to your 52 ohm line. The quarter wave will act as an impedence transformer and will step up the 52 to about 115 ohms. If your bridge then measures about 1.1:1, then you've got it. However, if you get a reading of about 4.4:1, that should give you a good indication that the impedence is around 26 ohms. You can solve that with a pair of 52 ohm lines using T connectors. One precaution thought, DON'T start worshiping the SWR god. A good antenna will still be a good antenna even if it has a 5:1 ( or greater ) SWR. The problem then is to MATCH the impedence, not the coax. Best Ed ------------------------------------- Name: ed sleight E-mail: k4sb@avana.net Time: 2:21:33 PM This message was sent by Chameleon ------------------------------------- >From broz@csn.net (John Brosnahan) Tue Oct 15 20:26:19 1996 From: broz@csn.net (John Brosnahan) (John Brosnahan) Subject: SUMMARY: Computer Cabinets Message-ID: <199610151926.AA26368@ns-1.csn.net> Finally modified my computer power supply to include an AC line filter (Corcomm) in place of the connector. The interference went away! (Seems quiet even with the cover removed.) Looks like the trend to mini-towers and their smaller power supplies and the trend to cheapen up the manufacturing costs have eliminated or minimized the required filtering on the AC line and the addition of commercial filters seems to solve the problem. The only difficult part is widening the AC connector hole a bit to make it accomodate the slightly wider filter using a nibbling tool and a file, and (in one case) to bend over a component on the printed circuit board to clear the case of the filter. 73 John John Brosnahan W0UN 24115 WCR 40 La Salle, CO 80645 "Radio Contesting IS a Contact Sport" >From ken.silverman@CCMAIL.AirTouch.COM (Ken Silverman) Tue Oct 15 21:44:15 >1996 From: ken.silverman@CCMAIL.AirTouch.COM (Ken Silverman) (Ken Silverman) Subject: EU Layers Message-ID: <9609158454.AA845409010@CCMAIL.AIRTOUCH.COM> K1KP writes: >Those appearing in 75-100 percent of US logs would be first layer; those >in 50-74% would >be second layer, and so on. Maybe the percentages would need to be adjusted. I don't think this gets us where we want to go. This kind of percentage tells you the relative activity level of the station, but doesn't allow you to classify the "level". What may be a better approach is to only look at ARRL DX logs (or other logs where you send power levels) and determine the % of total stations that fall into a predefined category. For example: By looking at the % of 100w stations worked as compared to the total EU stations worked, you now begin to get a better look at whether you have hit that next "layer" of stations. You would need to do this over a few contests to get a better perspective. Sure people can lie about their power levels, but you have assume the report sent is still indicative of their "level" After all this, I don't quite know what we would get at... working a new "level" of stations likely says more about propagation on that day than anything else. Kenny WM2C/6 ```
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