Home |
Search |
Today's Posts |
#8
![]() |
|||
|
|||
![]()
In article ,
"Charlie J" wrote: Gary- The ideas that you are advancing may work...however they absolutely fly in the face of all conventional wisdom wrt installing an end fed antenna system on a non-steel boat using a modern antenna coupler/tuner. I have not personally tried what you are proposing, but I have personally installed many dozens of systems using the more conventional methods that are reported in the literature and...these methods work...5 by 9 reports first crack out of the box. Do not misunderstand me, I am simply stating that installing the coupler/tuner as close as possible to the feed point of either a shipboard vertical or an insulated backstay, when the other half of the system is a modest counterpoise, yields very satisfactory results. Do you have any actual results from a system where the coupler/tuner where positioned close to the counterpoise? If you do, and you achieved good signal reports, than maybe the actual position of a coupler/tuner is irreverent. 73- Charlie KS4VB Charlie, What you say above, does not constitute any real objective information about the operation of an "End Feed Wire Antenna System. First off, Gary is ABSOLUTLY Right on everything he stated in the Post. All one has to do is go back to the days of Marine Radio Design and Installation BEFORE autotuners came into the picture. Now maybe your experience doesn't go back that far, but back when it took a REAL Marine Radio Tech, to install and tune a Marine Radio System aboard a vessel, and there were a bunch of BASIC Rules for getting a System to work RELIABLY on multiple frequencies, when connected to a single Endfeed Wire Antenna. Gary laid them out very well. Now that we have Autotuners, it doesn't take a REAL Marine Radio Tech to install the system, but it does take following the RULES in order to make the System RELIABLE on multiple frequencies when feeding a single antenna. Ever wonder why there are multile MF and HF Antennas on Large Ships? Why would one need more than one antenna if things are as easy as you seem to imply? And this on Metal Hulled Large Ships, where ground isn't the problem. Just because you got a 5-9 from your first contact doesn't mean SQUAT, about how well your antenna/ground system is working. If the band is open for that distance at that frequency, a "Wet Noodle" would allow for the recived signal report. I've received Good Signal Reports from KMI in California, while testing SOLAS Required System in harbors in Alaska, with the radio connected to a Dummy Load. That type of eveidence is not meaningful. The Laws of Physics haven't changed since Autotuners were invented. The same BASIC Rules still apply to Installation and operation of Marine Radio Systems. The only thing that has changed is that the installer no longer has to sit for a couple of hours trying to get a BAD Rf Ground System to tune a marginally installed Endfeed Wire Antenna across the MF & HF Marine Radio Channels. With Autotuners, all the installer needs to see is the TUNED Annuciator come up on the Radio Display, and he considers himself Done. What he doesn't see, is exactly how the autotuner has decided to actually tune the antenna it is hooked to, and where the Rf Energy is going now that the tuner says that it is done. If you had ever done any REAL Testing of Autotuners, you would know their very REAL Limitations on what they can tune for, and what drives them to find the equivelent of a Dummy Load, as the TUNED condition. I have spent many hours doing testing of autotuners for SEA. (now defunkt) I have worked with the two guys who designed, built, and tested ALL of the SEA SSB Radio's they ever built including a number that were never marketed. We all worked at Northern Radio Company, back in the 70's when Marine Radio, and MF/HF Point to Point Systems were the Primary Communications Links in the State of Alaska. What you don't understand is that your "Conventinal Wisdom" comes from a bunch of guys who have little or no REAL Experience in Marine Radio Technology, but have installed a few radios on a few small vessels and have been able to communicate with them to some degree or another. Guy's like Gordie West and that ilk. Their "Convertinal Wisdom" has always been suspect, by the Professional Techs, who actually do go out in the REAL world and keep Mariners communicating 24/7 no matter if the band is open or not, and not just for the "Weekend Worrior's" in their Plastic Hulled boats. Bruce in alaska -- add a 2 before @ |
Thread Tools | Search this Thread |
Display Modes | |
|
|
![]() |
||||
Thread | Forum | |||
Notes on short SSB antennas, for Larry | Cruising | |||
Generator - connection of neutral and ground wire. | Electronics | |||
SSB Resonant Ground Wires | Cruising | |||
Electric Grounding - steel hull | General |