on the move for 2011
The move began in 2010 before the old year closed. The move is to install and experiment with a half wave vertical over another half wave vertical, a collinear vertical. This is supposed to be almost an impossibility at HF, and more so at 40-meters. One half wave on 40-meters is about 66-feet, so that length placed over another looks like 132-feet of vertical antenna standing up in the air. Well I have devised a way to simulate this and we will test the performance very soon. I have not found any information on Google about 1/2 wave over 1/2 wave vertical antennas yet, so I am sorta working in the dark, but we have some ideas about the direction that we should take. The biggest challenge here is how to mount and connect the two verticals end to end with an insulator.
In the last high winds of the 2010 hurricane season the 31-foot vertical came down in pieces, with guy wires still attached. That vertical was repaired and is up again, making way for the new antenna which is a rebuild and recycle of the aluminum from the short 1/8 wave top and bottom loaded vertical antenna. Having given hams in the US a taste of the 31-foot vertical they kept calling for it to replace the short top and bottom loaded vertical antenna being used in the interim. If the 1/4 wave antenna is functioning on transmit as good as it does on receive, then I love it. Full sized vertical dipoles are hard to beat. Full sized verticals come with a price but the top and bottom loaded verticals are just as good but without the price. A good introduction can be found at EI7BA's website, just scale and build.
The hams in V4 land claim that there are a few difficulties which keep them off the air. Top of the list is coax cable, followed by antenna wire and aluminum tubing. I personally do not have any problems with coax cable since I took a decision to use any kind of coax cable that was available to me. I get the impression that as far as some hams are concerned only one or two coax cable brands and sizes are applicable for ham radio use. I not aware that the RF output at the SO-239 connector of any transmitter has any preference for coax cable brand or size. I believe it is more a matter of feed line impedance. For more than 99% of my ham radio life I have used small coax cable like RG-59 for everything, from linear amplifier output right down to ugly baluns.
There is an abundance of 75-ohm coax cable on the island. Every now and then the cable tv company dumps various coax cables in the landfill. I am of the view that some, if not all, of these cable can be used for ham radio. Maybe in the USA these cables are not classified for ham radio use, but I pick up from Google that hams are successfully using the RG-6 cables without complaint or bother. Recently a local hardware store here offered RG-6 coax cable with copper braid. Most of the RG-6 cable around may be the cheaper version with aluminum shield and braid. This should not be a problem at all, because the PL-259 connector for crimping is readily available.
There was discussion about RG-8X coax cable for ham radio use, but no move towards procurement. I hope that in 2011 a drum or two of RG-8X can be imported for ham radio consumption. There are some hams who swear by RG-213 and other numbers, as to how they will fare with the bulk purchase of the cost effective coax cable is anyone's guess. Very early in this new year I must seek to obtain a piece of discarded RG-6 coax cable from the Cable TV maintenance, and conduct tests, to see what adverse conditions may exist during my operating sessions. In the worst case scenario when antenna wire is scarce and an abundance of discarded coax cable exist, a ham may use shorted coax cable in place of the antenna wire. Another good substitute for antenna wire is telephone drop wire, but for hams wanting the real deal, check www.thewireman.com
My Kenwood TS-940SAT made in Japan in 1985/86 is still functioning but at less than 100% efficiency. This may be an indication that I should begin to prepare for a second radio on the operating table. I believe that I had enough from radios made in Japan. I am not now into bells and whistles, but plain old high performance, and the receivers listed on the Sherwood Engineering Receiver Test data table is the point of reference. A long time ago it was determined that a receiver with a Dynamic Range Narrow Spaced of 80dB @ 2 KHz was the minimum specs for a high performance ham receiver. Only a few radios on the market today meet this minimum specs. For some time the radios made in the USA dominated, but now one Asian model has found its way into a top position.
Every ham sets a different criteria for their ham radio equipment procurement. I am very interested in after sales service, and that is a deliverable from all USA ham equipment makers now. I believe that the non-us equipment maker is not looking out for the American ham radio consumer, never did and never will, so the local US equipment makers have to be there for them. From the receiver test data table, three brands of radios are more than enough to choose from, and it could become even more difficult because these receivers all meet and exceed the minimum specs. Each brand presents a unique perspective to ham radio and could satisfy every ham radio operator's need. From Elecraft to Flex-radio, and to Ten-Tec, whatever you need in a ham radio package it is right here.
It is so hard for me to choose which brand of radio I should have next. My ham radio friends think that I should invest in something new, the new technology, and leave the old radios behind. I tend to agree with them, but I notice that the new equipment and technology is now built to a different specification, and does not seem to offer the flexibility of the older, previous generation. For strict ham radio operating this crop of equipment is ideal, top of the line, you can't get any better than this. End of that story.
Unfortunately, some of us in this part of the world of ham radio, also have to contend with emergency and disaster preparedness and services. It is what we hams in these small countries do, in conjunction with the Nation's division of National Security. Intra and inter island communications is sometimes critical to the management of an emergency or disaster, depending on the magnitude and scope. Usually there is a limit to the radio communications and its operators, because the personnel relied upon have dual and triple roles to play. The hardware may not be a problem but having "communications only" operators could be. The ham operators can fill that gap for communications, and most times their personal equipment is used, for many more reasons than one.
Intra island communicating is okay, but if inter island and international communications are to be considered we have to be sure that our ham radio equipment can interface with the communications system of overseas and foreign agencies for effective and efficient transfer of information like fax, data, emails, voice, and so on. Our equipment has to be compatible or else somewhere along the line sync will be lost, data is missing and the communicating system crashes. You cannot have that happening in an international emergency communications system. Regrettably the new ham radio equipment of today is built to a specification that does not meet the requirement of the commercial equipment standard necessary for international emergency communications. Even with some add on accessories these ham radios still fall short.
A ham operator and his/her ham radio station does not have to cater for any operating above and beyond the call of ordinary ham radio operation. I personally prefer to have a ham radio station with full capability of both ham radio and commercial operation. This would mean that I will either have a separate radio for commercial communications or a radio capable of performing both tasks. The final decision may depend on the funds available to provide for the required setup. There is commercial radio equipment on the market today that also cater for ham radio operation, which lend themselves rather nicely to either complement the ham radio station lineup or to be the sole radio station's transmitter and receiver. This is typical commercial radio system and browsing the website may also prove informative. Different strokes for different folks and some ham operators may be quite comfortable with a popular brand of commercial radio equipment that will help them to meet the requirements.
As to the specifics on upgrading the ham radio station at V44KF, only time will tell, because ham radio is just a hobby, it is what I can do in my spare time, it does not put food on the table, and does not pay the electricity bills, it helps me to stay at home at night and avoid the risk of getting mugged or shot at on the street .... I could also be mugged and shot at inside my house anyway, but in actuality, I may really wait to upgrade when there is a duty free concession on our ham radio equipment which can be commandeered by National Security for use in emergency and disaster communications, and when our ham radio equipment is listed in the VAT exemption schedule like the radios for the fishermen ... in the mean time I will continue to look around for the best deal on 'top of the line' ham radio and commercial radio equipment that seem to have the capability to make it onto my ham radio station's operating table sometime in 2011.
I hope that you and your ham radio are on the move too.
In the last high winds of the 2010 hurricane season the 31-foot vertical came down in pieces, with guy wires still attached. That vertical was repaired and is up again, making way for the new antenna which is a rebuild and recycle of the aluminum from the short 1/8 wave top and bottom loaded vertical antenna. Having given hams in the US a taste of the 31-foot vertical they kept calling for it to replace the short top and bottom loaded vertical antenna being used in the interim. If the 1/4 wave antenna is functioning on transmit as good as it does on receive, then I love it. Full sized vertical dipoles are hard to beat. Full sized verticals come with a price but the top and bottom loaded verticals are just as good but without the price. A good introduction can be found at EI7BA's website, just scale and build.
The hams in V4 land claim that there are a few difficulties which keep them off the air. Top of the list is coax cable, followed by antenna wire and aluminum tubing. I personally do not have any problems with coax cable since I took a decision to use any kind of coax cable that was available to me. I get the impression that as far as some hams are concerned only one or two coax cable brands and sizes are applicable for ham radio use. I not aware that the RF output at the SO-239 connector of any transmitter has any preference for coax cable brand or size. I believe it is more a matter of feed line impedance. For more than 99% of my ham radio life I have used small coax cable like RG-59 for everything, from linear amplifier output right down to ugly baluns.
There is an abundance of 75-ohm coax cable on the island. Every now and then the cable tv company dumps various coax cables in the landfill. I am of the view that some, if not all, of these cable can be used for ham radio. Maybe in the USA these cables are not classified for ham radio use, but I pick up from Google that hams are successfully using the RG-6 cables without complaint or bother. Recently a local hardware store here offered RG-6 coax cable with copper braid. Most of the RG-6 cable around may be the cheaper version with aluminum shield and braid. This should not be a problem at all, because the PL-259 connector for crimping is readily available.
There was discussion about RG-8X coax cable for ham radio use, but no move towards procurement. I hope that in 2011 a drum or two of RG-8X can be imported for ham radio consumption. There are some hams who swear by RG-213 and other numbers, as to how they will fare with the bulk purchase of the cost effective coax cable is anyone's guess. Very early in this new year I must seek to obtain a piece of discarded RG-6 coax cable from the Cable TV maintenance, and conduct tests, to see what adverse conditions may exist during my operating sessions. In the worst case scenario when antenna wire is scarce and an abundance of discarded coax cable exist, a ham may use shorted coax cable in place of the antenna wire. Another good substitute for antenna wire is telephone drop wire, but for hams wanting the real deal, check www.thewireman.com
My Kenwood TS-940SAT made in Japan in 1985/86 is still functioning but at less than 100% efficiency. This may be an indication that I should begin to prepare for a second radio on the operating table. I believe that I had enough from radios made in Japan. I am not now into bells and whistles, but plain old high performance, and the receivers listed on the Sherwood Engineering Receiver Test data table is the point of reference. A long time ago it was determined that a receiver with a Dynamic Range Narrow Spaced of 80dB @ 2 KHz was the minimum specs for a high performance ham receiver. Only a few radios on the market today meet this minimum specs. For some time the radios made in the USA dominated, but now one Asian model has found its way into a top position.
Every ham sets a different criteria for their ham radio equipment procurement. I am very interested in after sales service, and that is a deliverable from all USA ham equipment makers now. I believe that the non-us equipment maker is not looking out for the American ham radio consumer, never did and never will, so the local US equipment makers have to be there for them. From the receiver test data table, three brands of radios are more than enough to choose from, and it could become even more difficult because these receivers all meet and exceed the minimum specs. Each brand presents a unique perspective to ham radio and could satisfy every ham radio operator's need. From Elecraft to Flex-radio, and to Ten-Tec, whatever you need in a ham radio package it is right here.
It is so hard for me to choose which brand of radio I should have next. My ham radio friends think that I should invest in something new, the new technology, and leave the old radios behind. I tend to agree with them, but I notice that the new equipment and technology is now built to a different specification, and does not seem to offer the flexibility of the older, previous generation. For strict ham radio operating this crop of equipment is ideal, top of the line, you can't get any better than this. End of that story.
Unfortunately, some of us in this part of the world of ham radio, also have to contend with emergency and disaster preparedness and services. It is what we hams in these small countries do, in conjunction with the Nation's division of National Security. Intra and inter island communications is sometimes critical to the management of an emergency or disaster, depending on the magnitude and scope. Usually there is a limit to the radio communications and its operators, because the personnel relied upon have dual and triple roles to play. The hardware may not be a problem but having "communications only" operators could be. The ham operators can fill that gap for communications, and most times their personal equipment is used, for many more reasons than one.
Intra island communicating is okay, but if inter island and international communications are to be considered we have to be sure that our ham radio equipment can interface with the communications system of overseas and foreign agencies for effective and efficient transfer of information like fax, data, emails, voice, and so on. Our equipment has to be compatible or else somewhere along the line sync will be lost, data is missing and the communicating system crashes. You cannot have that happening in an international emergency communications system. Regrettably the new ham radio equipment of today is built to a specification that does not meet the requirement of the commercial equipment standard necessary for international emergency communications. Even with some add on accessories these ham radios still fall short.
A ham operator and his/her ham radio station does not have to cater for any operating above and beyond the call of ordinary ham radio operation. I personally prefer to have a ham radio station with full capability of both ham radio and commercial operation. This would mean that I will either have a separate radio for commercial communications or a radio capable of performing both tasks. The final decision may depend on the funds available to provide for the required setup. There is commercial radio equipment on the market today that also cater for ham radio operation, which lend themselves rather nicely to either complement the ham radio station lineup or to be the sole radio station's transmitter and receiver. This is typical commercial radio system and browsing the website may also prove informative. Different strokes for different folks and some ham operators may be quite comfortable with a popular brand of commercial radio equipment that will help them to meet the requirements.
As to the specifics on upgrading the ham radio station at V44KF, only time will tell, because ham radio is just a hobby, it is what I can do in my spare time, it does not put food on the table, and does not pay the electricity bills, it helps me to stay at home at night and avoid the risk of getting mugged or shot at on the street .... I could also be mugged and shot at inside my house anyway, but in actuality, I may really wait to upgrade when there is a duty free concession on our ham radio equipment which can be commandeered by National Security for use in emergency and disaster communications, and when our ham radio equipment is listed in the VAT exemption schedule like the radios for the fishermen ... in the mean time I will continue to look around for the best deal on 'top of the line' ham radio and commercial radio equipment that seem to have the capability to make it onto my ham radio station's operating table sometime in 2011.
I hope that you and your ham radio are on the move too.
Comments
One thought for reducing the height of your stacked verticals would be to make each one as KF2YN's "C-Pole antenna" which is less than half the vertical height but still a full half-wave dipole.
The original QST article is available from http://tk5ep.free.fr/tech/cpol/0404037.pdf and an on-line calculator for the dimension is at http://www.svrc.org/cpolecalc.php
I'm using one on 20m - it's only 4.5m high and works very well.
Cheers
Giovanni - ZL2GX