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Sorry, I was getting tired. There is one consideration that does need
to be addressed though, and that is ease of use. Not all these installations will be manned or womanned by honest to goodness radio operators, or even knowledgeable operators, so for the sake of operation by neophytes in an emergency when out of range of VHF/UHF an auto tuner would be one less thing to figure out how to use. That's just my opinion. -- The Road Warrior Hobbit no -- it's NOT ok to contact this account with services or other commercial interests "Me" wrote in message ... | In article , | "Mungo Bulge" wrote: | | Me is thinking "I'm vindicated" and Chucky is thinking "Another nut | case". You're both right. So why does it work, simple. The antenna isn't | a Marconi; it's an industry standard Marine HF band antenna, 2-30 MHz | bandwidth, 10.8 MHz resonant frequency, 23 feet high and when | connected to an HF radio set configured to its manufacturer's | specifications it will perform admirably. If that were not the case, | we would have had to have had at the very least five quarter wave | Marconi antennae ranging in height from 7.8 to 117 feet and we don't. | | That Chucky is the proper use of reductio ad absurdum logic. | | Really close Mungo, but the antenna you are talking about doesn't really | have 2-30Mhz Bandwidth, at all. It is a Marconi tuned by an Autotuner, | to make it look like a 50 Ohm load to the radio so that the radio will | transfer as much power as possible to the antenna, minus what is lost in | RF Ground. If the RF Ground impedance is higher than the Antenna | Impedance, with the autotuner doing it's best to make the whole system | appear to the transmitter as 50 Ohms, then most of the RF Energy will | dissipated in the RF Ground and lost to the communicator. Autotuners | suck, when compared to any manual tuner, specifically due to the way the | tuning software has to impliment changes in binary steps, and how the | Phase Detector Sensors provide feedback to the processor while doing a | tuneup. This all plays heavily into the design of the antenna system | connected to the autotuner, as any good tech will put the "Untunable" | 1/2 Lambda Frequency in a portion of the spectrum that the user will | NEVER Need to use. | | There is a lot of practical considerations that MUST be considered | when designing, and installing MF/HF Marine Radios on any vessel, but | plastic and cellulose hulled vessels make all these things very much | harder to compromise into an Effective Radio Installation. | | Me |
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