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Your test doesn't mean crap, and I'll tell you why. For starters, your -first- test (that you failed to mention) using -two- receivers came up with inconsistent results for five different antennas tested on the transmitter: Yes it did yield a inconsistency but the inconsistency was brought about by very close results judged by real people. Something you should expect in the real world. The second test (31" S-meter) was like a slow motion replay. It gave me the ability to take more of the human factor out. Regardless of the inconsistency it was still shown that a 1/4 wave SS antenna could be beat by a shorter antenna. This was consistent with BOTH receivers. Tentec: F, 3.1 s units E, 3.05 A, 3 B, 2.85 D, 2.7 C, 2.65 Kenwood: F, 2.3 s units E&B tied at 2.2 D-C tied at 2.15 A, 2.1 This tells me that something is -definately- wrong with your testing procedure. The conditions of this test follow: 1. All connected to Hustler Quick disconnects That could be an issue if one or more of the connectors were not clean, assuming they didn't use the same connector; They all used brand new connectors 2. All used at 1.5 : 1 match or better The match for each antenna was not listed, and I can only assume that they were different. Regardless, what was the forward power with each antenna, and why was that not listed? They were all adjusted for a SWR null before the test. 3. All tested with a constant tone, constant power transmitter Using....? An audio signal generator and a TRC-453? Was the radio modded? What was the modulation percentage? A transmitter with no alc set for a constant low power carrier was used. 4. All used on a three magnet mount on the roof of a truck Now there's a BIG problem -- improper grounding! Then at least they were all grounded similarity. 5. All tested from a parked vehicle that never moved during each test How did the radio get power? Cigarette lighter? Six feet of 00-guage superflex? Was the engine running? If not, was the battery voltage checked before and after the tests? The vehicle was off without any reduction of battery voltage over the very short period of the test. 6. All tested within a very brief time period of each other (15 sec.) Save for the all-too-uncommon microburst, how is that significant? Your microburst? The one that occurred when I posted this test? 7. All used a stationary Kenwood 940 receiver. Why didn't you use two receivers for the second test? Because it was not needed. The ability to store and review the info was more useful. 8. The 940 used a vertical beam free and clear of obstacles. Beam, schmeam. What was the resonant frequency of the antenna for the receiver? What kind of match was on the receiver? Were all antennas tuned and tested on the same freq? Everything was done on the same frequency. It doesn't matter what frequency the receiving antenna was resonant on. All the received signals were treated the same. 9. A video camera and a 31" television was used to display a (31" S- METER) and record the results. Thirteen mile free and clear of obstacles. At 13 miles, another issue you will have is radiation angle. I don't suppose you measured that either, did you? Do you know why that is important? Because you don't state the HAAT of the antenna for either the transmitter or the receiver, nor do you state whether the 13/24 miles was flat. If you just wanted to get a relative signal strength reading without the confound of HAAT, why did you stroll 13 miles instead of only half a mile or so? All you needed to do was clear the near-field, which most engineers consider to be six wavelengths for HF (or 66 meters, a far cry from 13 miles where a lot can happen inbetween). I just posted the numbers. They are typical of real world results. It's to bad that you can't stand that 1/4 wave SS whip can be beat. There are WAY too many issues with your test, and any or all of them could have been a factor in your inconsistent readings. Looking back an those threads, it appears that you already knew that, too. I'm sorry that you are upset. The numbers speak for themselves. If you don't like them then get off your ass and run a test yourself. |
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