Archive for the ‘antennas’ Category
The FA-VA4 Vector Antenna Analyzer (LF-100MHz)
December 11th, 2017 | 
Author: 
For some time I had been considering the purchase of the MFJ259 antenna analyzer but after a little online sleuthing, came across this little beauty, the FA-VA4 Antenna Analyzer by Funk Amateur in Germany and available through their Box73 website here.
I liked the fact that the cost of the analyzer was about half that of anything else comparable ($140 US including shipping) and that it covered the new 2200 / 630m bands!
I think many amateurs planning on building a system for either of these new bands will find the very affordable FA-VA4 a handy piece of equipment when it comes to working on their LF / MF antenna since most available SWR meters do not cover these frequencies accurately.
Delivery time was fast and everything was very well packaged. The FA-VA4 comes in partial kit form and requires only a short amount of time to put together.
The necessary assembly consists of soldering pin strip connectors, switches, AA cell holders, and the BNC connector. All of the tricky SMD components have been pre-mounted ... total assembly time was less than 60 minutes and everything fired-up nicely, without problems, thanks to the well written instruction / user manual.
Included with the kit are three BNC connectors needed to calibrate the instrument for the highest accuracy. These consist of a 'Shorted' connector, an 'Open' connector and a 50 ohm 'Load' connector (SOL). A simple three-part calibration procedure for all frequencies takes about 15 minute to complete, while the instrument calibrates itself as it scans through all frequency ranges with each connector plugged into the output. Once this task is completed, the analyzer is ready for use.
If you're like me, I think the main use will be to check out and tweak some of your HF antennas using the SWR or Z sweep function. This allows you to set a desired 'center' frequency along with a + / - sweep range and have the display draw a nice plot of your system.
Had my 630m antenna not already been tuned and matched, I would have found the analyzer to be a great help but, thanks to my 'scopematch', that antenna has already been optimised.
All menu features and data entry is via three momentary-contact push switches. Although this might initially seem awkward, it is not, and operation is pretty intuitive.
The main modes of operation are:
Single Frequency SWR Measurement
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| courtesy: http://www.box73.com/product/5 |
Single Frequency Impedance Measurement
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| courtesy: http://www.box73.com/product/5 |
Single SWR Measurement Run
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| courtesy: http://www.box73.com/product/5 |
Single Run For Impedance Measurement (Resistance and Reactance)
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| courtesy: http://www.box73.com/product/5 |
SWR Measurement On Five Frequencies (5 Band Measurement)
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| courtesy: http://www.box73.com/product/5 |
As well, all of the above can be viewed in a continuous 'cycle' mode, as inputs are changed and all screens can be saved for future reference.
Additional capabilities include use in an HF Signal Generator Mode (~ 1V square wave @50 ohms), the ability to measure C and L at a given frequency, as a 'dip meter' and to measure cable resonances and determine lengths.
The complete manual may also be downloaded from their website here.
I will soon put all of my antennas to the test and see what work might need to be done to optimize them, particularly my HF half slopers, which, in spite of their great performance, have always proven a bit of a mystery when it comes to pruning them to resonance ... I rather suspect that the sloping wires are more of an impedance tuning stub than a radiator and that most radiation comes from the vertical support tower, not the sloping wire.
All-in-all, the FA-VA4 appears to offer very good value for the money and is a well built, quality test instrument. I think it will become a popular choice among hams, especially those on LF / MF. The only thing different that I would have liked, would be to have a UHF (SO 239) connector rather than a BNC on the output, since most amateurs are using these on their HF systems ... or, the inclusion of a BNC-to-UHF adapter.
If you already use this device, please feel free to add your comments below!
It’s been a long, long time.
It has indeed been a long time since I've moved to this new work location. The old work QTH was in Warren, NJ and the new is in Whitehouse Station, NJ. Same job, same company, different campus. I am about 10 miles (more or less) farther west into the interior of New Jersey than I used to be. It adds about another 10 minutes to my commute.
There are two of us in my department. Things were easier in Warren, as we both worked from the same (and only) building on campus. We staggered our lunch breaks so that one of us was always on duty. Here, at the new work QTH, we are split between two buildings, each one of us minding our own store, so to speak. Unless you master bi-location, you can't manage both buildings at the same time with one man.
That led towards a hiatus in lunchtime QRP operations as it just seemed not the greatest idea to spend so much time away from the desk. I know, it's time I'm entitled to (it's only an hour) and I really should get away from the desk to remain fresh in the afternoon.
So I decided to take advantage again, beginning this week.
I went out to the car yesterday and hooked up the KX3 to the Buddistick. I heard a lot of stations on 20 Meters, but got no answers to any of my calls. I know the equipment works, I figured it was just a bit of "rust" on my part. But, boy howdy, was it hot yesterday! It reached into the upper 80s (about 30C) here at lunchtime and since I was parked outside, it was hot like an oven in the car. It was a double negative experience - too hot and skunked on contacts.
Not one to be deterred, my little eye spied on something that I had forgotten. This campus has picnic tables! Many of the employees go out to eat outdoors on the nice days. There are plenty of tables, they are spaced widely enough apart where conversations cannot encroach on one another.
It dawned on me that this would be the perfect place to set up the KX3 and the magloop! Sure, I'd probably get some stares from the other lunchers, and maybe from some of the employees who take advantage of their lunch break to walk the perimeter of the campus - but what they heck? Right? It's not like I haven't been stared at before. It's not like people haven't come up to me to ask, "What is that?" before, so tossing self-consciousness into the wind, I decided to set up at one of the tables today.
I chose a table towards the end of the line of tables, the one with no umbrella. Sure, it would be a little hotter with no shade, but it's less than an hour and besides, there's be no metallic umbrella ribs to possibly interact with the magloop.
Before hunting for a QSO, I decided to call CQ for a bit on both 20 and 17 Meters. I really didn't expect anyone to answer, although there's no reason why anyone wouldn't. I just wanted to conduct a little Reverse Beacon Network experiment.
Experiment done, I went back to 20 Meters and found the "sweet spot" with the loop's tuning capacitor. (I was able to set up in under four minutes, by they way. Almost as fast as setting up the Buddistick on the car.) Tuning the KX3 around, there were a bunch of loud stations. Finally, I came upon GI4DOH, Rich in Northern Ireland. He had a strong signal and a great fist, so I gave him a call. He came back to me on the first shot! He was 559+ here in NJ, and I got a 559 in return.
According to his QRZ page, the loop that Rich is using is a receive only loop. This was not a loop to loop QSO.
After working Rich, I popped on up to 17 Meters. There I heard OE3DXA, Wern in Austria calling CQ. Again, loud signal, great fist, so I gave him a call. Just as with GI4DOH, I gave him a 599+ report but this time I got a 599 in return. Both QSOs were solid with no repeats asked for with regard to info, so I am assuming I was at or near Q5 copy. (Even if the 599 in return wasn't exactly accurate.)
It was time to pack it in, and I was satisfied with the two DX QSOs for the day. With regard to my Reverse Beacon Network experiment, this was where the loop was allowing my signal to be heard:
As for spectators, I did get one guy who stopped to ask, "What is that? And what are you doing?" I explained that it was Amateur Radio and an Amateur Radio antenna. In response, I got the (what seems to be standard) "People still do that?" question.
I went into "pitch" mode and explained that yes, Amateur Radio is alive and well, and that for a lot of people in the Caribbean right now it's the only way they can get word out to their families abroad, that they are OK after the hurricanes.
So it was a successful day, I'm happy and it looks like there might not be rain for the rest of the work week.
72 de Larry W2LJ
QRP - When you care to send the very least!
There are two of us in my department. Things were easier in Warren, as we both worked from the same (and only) building on campus. We staggered our lunch breaks so that one of us was always on duty. Here, at the new work QTH, we are split between two buildings, each one of us minding our own store, so to speak. Unless you master bi-location, you can't manage both buildings at the same time with one man.
That led towards a hiatus in lunchtime QRP operations as it just seemed not the greatest idea to spend so much time away from the desk. I know, it's time I'm entitled to (it's only an hour) and I really should get away from the desk to remain fresh in the afternoon.
So I decided to take advantage again, beginning this week.
I went out to the car yesterday and hooked up the KX3 to the Buddistick. I heard a lot of stations on 20 Meters, but got no answers to any of my calls. I know the equipment works, I figured it was just a bit of "rust" on my part. But, boy howdy, was it hot yesterday! It reached into the upper 80s (about 30C) here at lunchtime and since I was parked outside, it was hot like an oven in the car. It was a double negative experience - too hot and skunked on contacts.
Not one to be deterred, my little eye spied on something that I had forgotten. This campus has picnic tables! Many of the employees go out to eat outdoors on the nice days. There are plenty of tables, they are spaced widely enough apart where conversations cannot encroach on one another.
It dawned on me that this would be the perfect place to set up the KX3 and the magloop! Sure, I'd probably get some stares from the other lunchers, and maybe from some of the employees who take advantage of their lunch break to walk the perimeter of the campus - but what they heck? Right? It's not like I haven't been stared at before. It's not like people haven't come up to me to ask, "What is that?" before, so tossing self-consciousness into the wind, I decided to set up at one of the tables today.
I chose a table towards the end of the line of tables, the one with no umbrella. Sure, it would be a little hotter with no shade, but it's less than an hour and besides, there's be no metallic umbrella ribs to possibly interact with the magloop.
Before hunting for a QSO, I decided to call CQ for a bit on both 20 and 17 Meters. I really didn't expect anyone to answer, although there's no reason why anyone wouldn't. I just wanted to conduct a little Reverse Beacon Network experiment.
Experiment done, I went back to 20 Meters and found the "sweet spot" with the loop's tuning capacitor. (I was able to set up in under four minutes, by they way. Almost as fast as setting up the Buddistick on the car.) Tuning the KX3 around, there were a bunch of loud stations. Finally, I came upon GI4DOH, Rich in Northern Ireland. He had a strong signal and a great fist, so I gave him a call. He came back to me on the first shot! He was 559+ here in NJ, and I got a 559 in return.
According to his QRZ page, the loop that Rich is using is a receive only loop. This was not a loop to loop QSO.
After working Rich, I popped on up to 17 Meters. There I heard OE3DXA, Wern in Austria calling CQ. Again, loud signal, great fist, so I gave him a call. Just as with GI4DOH, I gave him a 599+ report but this time I got a 599 in return. Both QSOs were solid with no repeats asked for with regard to info, so I am assuming I was at or near Q5 copy. (Even if the 599 in return wasn't exactly accurate.)
It was time to pack it in, and I was satisfied with the two DX QSOs for the day. With regard to my Reverse Beacon Network experiment, this was where the loop was allowing my signal to be heard:
As for spectators, I did get one guy who stopped to ask, "What is that? And what are you doing?" I explained that it was Amateur Radio and an Amateur Radio antenna. In response, I got the (what seems to be standard) "People still do that?" question.
I went into "pitch" mode and explained that yes, Amateur Radio is alive and well, and that for a lot of people in the Caribbean right now it's the only way they can get word out to their families abroad, that they are OK after the hurricanes.
So it was a successful day, I'm happy and it looks like there might not be rain for the rest of the work week.
72 de Larry W2LJ
QRP - When you care to send the very least!
Amateur Radio …. sort of
Today was a busy day with a lot of commitments and a lot of chores and not much time for Amateur Radio. So what does an intrepid Amateur Radio op do? Put his tail between his legs and slink off into the distance? No, he does the next best thing - he engages in related activities.
I had a class this morning that meets one Saturday a month. It started last September and ends next month, and it runs from 9:00 AM to 1:00 PM. You can see that that's a good chunk of the day. So it was SOTABEAMS WSPRLite to the rescue! It's kind of like a Ronco counter top oven - "set it and forget it". So I hooked up my WSPRLite to my W3EDP, set it up for 200 milliWatts on 20 Meters and let it go to town!
I figured that I'd let it run, see how the W3EDP gets out and still do the things I had to do today.
This WSPRLite is so cool! It's a software defined WSPR beacon in a package about half the size of an Altoids tin. It's powered by the USB port of your computer. You pick the band and power output and hook it up to your antenna. You wait until 2 seconds past any even minute and you press the little black button on the right to kick things off. The beacon transmits for 110 seconds and then waits for the next opportunity when the frequency is clear. I set it so that it would randomly transmit about 20% of the time; and you can let it run for up to three days if you want.
In the meantime, yesterday, while checking my e-mail, I saw that Joe Everhart N2CX co-founder of the NJQRP Club was going to be activating Edison State Park for Parks on the Air. It's designator is KFF-1615 and it's all of about 15 minutes from my house. So I e-mailed Joe back with my cell phone number and told him to text me when he got there; and I would come out and meet him.
After class I came home and broke out the lawnmower and got the front yard done. As I was walking to the backyard, I felt my pocket buzz. I whipped out my phone and read a text that Joe was on site and setting up. I dropped the lawnmower like a hot potato and high tailed it to the park. After all, what QRPer in his right mind would miss the opportunity to talk with a QRP Legend, right? When I got there, I saw Joe had finished setting up and was operating from his car.
It was getting out all right! Into the midwest USA and into Europe on 200 milliWatts! The W3EDP seems to be doing OK!
It turned out to be a good day, after all. I got to attend my class, got my chores done and got to hob-nob with a QRP giant - while giving my wire antenna a check out at the same time!
And here I thought the day would be a bust, Amateur Radio-wise!
72 de Larry W2LJ
QRP - When you care to send the very least!
I had a class this morning that meets one Saturday a month. It started last September and ends next month, and it runs from 9:00 AM to 1:00 PM. You can see that that's a good chunk of the day. So it was SOTABEAMS WSPRLite to the rescue! It's kind of like a Ronco counter top oven - "set it and forget it". So I hooked up my WSPRLite to my W3EDP, set it up for 200 milliWatts on 20 Meters and let it go to town!
I figured that I'd let it run, see how the W3EDP gets out and still do the things I had to do today.
This WSPRLite is so cool! It's a software defined WSPR beacon in a package about half the size of an Altoids tin. It's powered by the USB port of your computer. You pick the band and power output and hook it up to your antenna. You wait until 2 seconds past any even minute and you press the little black button on the right to kick things off. The beacon transmits for 110 seconds and then waits for the next opportunity when the frequency is clear. I set it so that it would randomly transmit about 20% of the time; and you can let it run for up to three days if you want.
In the meantime, yesterday, while checking my e-mail, I saw that Joe Everhart N2CX co-founder of the NJQRP Club was going to be activating Edison State Park for Parks on the Air. It's designator is KFF-1615 and it's all of about 15 minutes from my house. So I e-mailed Joe back with my cell phone number and told him to text me when he got there; and I would come out and meet him.
After class I came home and broke out the lawnmower and got the front yard done. As I was walking to the backyard, I felt my pocket buzz. I whipped out my phone and read a text that Joe was on site and setting up. I dropped the lawnmower like a hot potato and high tailed it to the park. After all, what QRPer in his right mind would miss the opportunity to talk with a QRP Legend, right? When I got there, I saw Joe had finished setting up and was operating from his car.
If you click on the picture to get a better view, you will notice that mounted at the rear of the car was Joe's 16 foot crappie pole. He had a loading coil attached and ran wire to the top. He told me that this arrangement seems to work for him as well as a full blown 31 foot mast secured via a drive on mast support. And who am I not to take him at his word? Joe is quite the QRP innovator. It seems that not an issue of "QRP Quarterly" goes by without some kind of juicy tidbit from Joe. And if N2CX says it works, then by golly, you can be assured that it works!
When I got there, Joe was making contacts on 40 Meters with his KX3. He noticed the same thing that I think we're all keenly aware of, that 20 Meters seems to stink, lately. Anyway, we kibbitzed for a few minutes and then I took my leave after Joe's son Kevin took a few photos of us together. After all, he came all the way to Edison from his home to make QSOs and put KFF-1615 on the air, not shoot the breeze with W2LJ!
When I got home, before I started on the back yard, I raced downstairs to the shack and hooked up the KX3 to the HF9V and went looking for Joe. I listened on 7.034 MHz, where I saw him operating from during our visit, only to hear not a peep. Figuring that he changed bands, I checked both 30 Meters and then 20 Meters, Bingo on 14.062 MHz (goundwave)! I got Joe in my log and helped him towards making the minimum number of contacts he needed to qualify for an activation.
Before resuming lawn duty, I decided to check WSPRNet, to see how the WSPRLite was getting out.
It was getting out all right! Into the midwest USA and into Europe on 200 milliWatts! The W3EDP seems to be doing OK!
It turned out to be a good day, after all. I got to attend my class, got my chores done and got to hob-nob with a QRP giant - while giving my wire antenna a check out at the same time!
And here I thought the day would be a bust, Amateur Radio-wise!
72 de Larry W2LJ
QRP - When you care to send the very least!
Amateur Radio …. sort of
Today was a busy day with a lot of commitments and a lot of chores and not much time for Amateur Radio. So what does an intrepid Amateur Radio op do? Put his tail between his legs and slink off into the distance? No, he does the next best thing - he engages in related activities.
I had a class this morning that meets one Saturday a month. It started last September and ends next month, and it runs from 9:00 AM to 1:00 PM. You can see that that's a good chunk of the day. So it was SOTABEAMS WSPRLite to the rescue! It's kind of like a Ronco counter top oven - "set it and forget it". So I hooked up my WSPRLite to my W3EDP, set it up for 200 milliWatts on 20 Meters and let it go to town!
I figured that I'd let it run, see how the W3EDP gets out and still do the things I had to do today.
This WSPRLite is so cool! It's a software defined WSPR beacon in a package about half the size of an Altoids tin. It's powered by the USB port of your computer. You pick the band and power output and hook it up to your antenna. You wait until 2 seconds past any even minute and you press the little black button on the right to kick things off. The beacon transmits for 110 seconds and then waits for the next opportunity when the frequency is clear. I set it so that it would randomly transmit about 20% of the time; and you can let it run for up to three days if you want.
In the meantime, yesterday, while checking my e-mail, I saw that Joe Everhart N2CX co-founder of the NJQRP Club was going to be activating Edison State Park for Parks on the Air. It's designator is KFF-1615 and it's all of about 15 minutes from my house. So I e-mailed Joe back with my cell phone number and told him to text me when he got there; and I would come out and meet him.
After class I came home and broke out the lawnmower and got the front yard done. As I was walking to the backyard, I felt my pocket buzz. I whipped out my phone and read a text that Joe was on site and setting up. I dropped the lawnmower like a hot potato and high tailed it to the park. After all, what QRPer in his right mind would miss the opportunity to talk with a QRP Legend, right? When I got there, I saw Joe had finished setting up and was operating from his car.
It was getting out all right! Into the midwest USA and into Europe on 200 milliWatts! The W3EDP seems to be doing OK!
It turned out to be a good day, after all. I got to attend my class, got my chores done and got to hob-nob with a QRP giant - while giving my wire antenna a check out at the same time!
And here I thought the day would be a bust, Amateur Radio-wise!
72 de Larry W2LJ
QRP - When you care to send the very least!
I had a class this morning that meets one Saturday a month. It started last September and ends next month, and it runs from 9:00 AM to 1:00 PM. You can see that that's a good chunk of the day. So it was SOTABEAMS WSPRLite to the rescue! It's kind of like a Ronco counter top oven - "set it and forget it". So I hooked up my WSPRLite to my W3EDP, set it up for 200 milliWatts on 20 Meters and let it go to town!
I figured that I'd let it run, see how the W3EDP gets out and still do the things I had to do today.
This WSPRLite is so cool! It's a software defined WSPR beacon in a package about half the size of an Altoids tin. It's powered by the USB port of your computer. You pick the band and power output and hook it up to your antenna. You wait until 2 seconds past any even minute and you press the little black button on the right to kick things off. The beacon transmits for 110 seconds and then waits for the next opportunity when the frequency is clear. I set it so that it would randomly transmit about 20% of the time; and you can let it run for up to three days if you want.
In the meantime, yesterday, while checking my e-mail, I saw that Joe Everhart N2CX co-founder of the NJQRP Club was going to be activating Edison State Park for Parks on the Air. It's designator is KFF-1615 and it's all of about 15 minutes from my house. So I e-mailed Joe back with my cell phone number and told him to text me when he got there; and I would come out and meet him.
After class I came home and broke out the lawnmower and got the front yard done. As I was walking to the backyard, I felt my pocket buzz. I whipped out my phone and read a text that Joe was on site and setting up. I dropped the lawnmower like a hot potato and high tailed it to the park. After all, what QRPer in his right mind would miss the opportunity to talk with a QRP Legend, right? When I got there, I saw Joe had finished setting up and was operating from his car.
If you click on the picture to get a better view, you will notice that mounted at the rear of the car was Joe's 16 foot crappie pole. He had a loading coil attached and ran wire to the top. He told me that this arrangement seems to work for him as well as a full blown 31 foot mast secured via a drive on mast support. And who am I not to take him at his word? Joe is quite the QRP innovator. It seems that not an issue of "QRP Quarterly" goes by without some kind of juicy tidbit from Joe. And if N2CX says it works, then by golly, you can be assured that it works!
When I got there, Joe was making contacts on 40 Meters with his KX3. He noticed the same thing that I think we're all keenly aware of, that 20 Meters seems to stink, lately. Anyway, we kibbitzed for a few minutes and then I took my leave after Joe's son Kevin took a few photos of us together. After all, he came all the way to Edison from his home to make QSOs and put KFF-1615 on the air, not shoot the breeze with W2LJ!
When I got home, before I started on the back yard, I raced downstairs to the shack and hooked up the KX3 to the HF9V and went looking for Joe. I listened on 7.034 MHz, where I saw him operating from during our visit, only to hear not a peep. Figuring that he changed bands, I checked both 30 Meters and then 20 Meters, Bingo on 14.062 MHz (goundwave)! I got Joe in my log and helped him towards making the minimum number of contacts he needed to qualify for an activation.
Before resuming lawn duty, I decided to check WSPRNet, to see how the WSPRLite was getting out.
It was getting out all right! Into the midwest USA and into Europe on 200 milliWatts! The W3EDP seems to be doing OK!
It turned out to be a good day, after all. I got to attend my class, got my chores done and got to hob-nob with a QRP giant - while giving my wire antenna a check out at the same time!
And here I thought the day would be a bust, Amateur Radio-wise!
72 de Larry W2LJ
QRP - When you care to send the very least!
LF / MF Antenna Planning
 |
| courtesy: Chuck Roblin |
For U.S. amateurs, the 2200 and 630m bands will soon be a reality and I have no doubt that there will be an accompanying surge in interest among large numbers of homebrewers and low band diehards.
It should be an exciting time as new stations gradually start to populate the band from coast to coast.
High on the 'to do' list will be the planning and building (or modifying) of a suitable antenna system for the band(s) of choice. For most, this will be new territory, but the reality is that there has been a long tradition of operation in the LF and MF bands in the U.S. for many years ... all under the Part 15 'Lowfer' and 'Medfer' service.
Although activity in this category has fallen off over the years due to the availability of the much less-restrictive Part 5 experimental licences, there is still a great legacy of literature and information left behind that is every bit as useful today as it was back in the golden years of Lowfer operations.
Here is one such document from Stephen McGreevy's Natural ELF-VLF Radio website that many newcomers to these bands may find very helpful as it covers a wide variety of LF antenna-related basics in a down-to-earth manner.
An even more detailed treatise on virtually all aspects of LF and MF antenna topics is that found on Rik, ON7YD's website. His antenna pages can be found here. Although originally developed for the 2200m band, the principles are equally applicable to 630m as well.
Hopefully both of these sources will help you decide how to get a working antenna system up and running on the new bands. And as always, much help is available via the Internet on the Lowfer Reflector, the RSGB LF reflector or on the 600MRG Reflector.
LF / MF Antenna Planning
|
| courtesy: Chuck Roblin |
For U.S. amateurs, the 2200 and 630m bands will soon be a reality and I have no doubt that there will be an accompanying surge in interest among large numbers of homebrewers and low band diehards.
It should be an exciting time as new stations gradually start to populate the band from coast to coast.
High on the 'to do' list will be the planning and building (or modifying) of a suitable antenna system for the band(s) of choice. For most, this will be new territory, but the reality is that there has been a long tradition of operation in the LF and MF bands in the U.S. for many years ... all under the Part 15 'Lowfer' and 'Medfer' service.
Although activity in this category has fallen off over the years due to the availability of the much less-restrictive Part 5 experimental licences, there is still a great legacy of literature and information left behind that is every bit as useful today as it was back in the golden years of Lowfer operations.
Here is one such document from Stephen McGreevy's Natural ELF-VLF Radio website that many newcomers to these bands may find very helpful as it covers a wide variety of LF antenna-related basics in a down-to-earth manner.
An even more detailed treatise on virtually all aspects of LF and MF antenna topics is that found on Rik, ON7YD's website. His antenna pages can be found here. Although originally developed for the 2200m band, the principles are equally applicable to 630m as well.
Hopefully both of these sources will help you decide how to get a working antenna system up and running on the new bands. And as always, much help is available via the Internet on the Lowfer Reflector, the RSGB LF reflector or on the 600MRG Reflector.
The JK BevFlex-4 Antenna
This past week, comments regarding an interesting new low-noise directionally-switched receive antenna popped-up on both the Topband reflector and the IRCA (BCB DXers) reflector.
The new JK BevFlex-4 is reported to work very well without requiring a lot of real estate for deployment. The antenna was designed by Geoff Mendenhall, W8GNM, and Ned Mountain, WC4X.
There are several things that make this package a little different. The antenna can be configured in four basic forms: CLASSIC BEVERAGE, BEVERAGE ON GROUND (BOG) / BEVERAGE IN SOD (BIS), INVERTED EWE, or as a FLAG. What is quite different however is its flexible feedpoint allowing the antenna to be fed at any point along its length when used in the BOG or BEVERAGE configuration. The antenna is completely passive and requires no preamplification although, in some configurations, it is suggested for use above 7MHz.
Full details can be found at the JK Antennas website, as well as the manual and a FAQ page.
The FAQ sheet indicates that it will perform from LW through to 10m but the most dramatic improvement in reception from users has been noted on the lower bands. It sounds like it might make an interesting antenna for NDB DXing as well.
In the BOG form, the antenna can lay right on the ground or be buried (BIS) just below the surface using RG-6 for the actual antenna element. Other configurations allow much smaller, stealth-sized wire to be employed.
An interesting YouTube video of the antenna in action as well as an in-depth description may be viewed here:
Here is one comment from an east coast topbander:
I also bought one this year....deployed it as an EWE, as that’s all the room
I have, small lot in a subdivision.....in order to work them you need to
hear them, and once I put that up, I could hear !!! first put up as EU/VK-ZL
and worked several in the DX contest, but when the african dxpedetions were on, moved it to due east/west., and worked all of them, S01, etc.....front to back is remarkable on 160, it works ok on 80, (mine was 10ft high and 38 ft long) but really rocks on 160 !!!!, and really cuts down the line noise/static I normally hear on my transmit Inv L.
Perhaps this may be your answer for a small effective receive antenna for LW and above but even if not, their website description makes for interesting reading.
