I got cables made for the test, and got two antennas tested in my garden. Fortunately the weather kept dry for the tests.
Test setup :
Signal generator,
Test antennas, mounted on a 3m mast :
- 10m half wave vertical
- 6m half wave vertical
3 RX antennas .
- The R6000 on a 3m mast antenna in the other end of the garden
- The V-2000 antenna a bit closer, but at 6m
- The 4m half wave, not far from the R6000, also at about 6m
I had intended to use a R7100 RX, but the s-meter had far too much drift, probably due to heat, so that was discarded, I was then using my IC-7100 and IC-7300 in the shack, with a combination of the aforementioned antennas. Much more stable S-meter readings.
The paint is purchased from a military surplus shop, and is spray paint. One can could cover the two antennas.
No significant difference could be detected in the signal levels on either 10m or 6m. The paint had been approved by me for reducing the visibility of aluminium antennas for HF, 6 and 4m. More paint has been ordered.
When I get my R-6000 antenna for 6 - 20m painted, I will make some pictures of the visibility before/after the paint job. This time it is not just a test, so it should be more thorough and even ;) .
Why do I paint my antennas ?
Well, I like to have as extensive an antenna system as possible, but a "normal" system of that sort would be extremely visible to neighbours. A lot of my antennas for HF, 6m and 4m have trees as background (not the sky), so all shiny objects, like aluminium antennas become all too obvious, especially in bright (and low angle) sunlight.
The paint tested is "NATO Green", and I have also some brown and matte black paint that I intend to use sparingly, probably making some lighter and darker spots on the antennas, improving the camouflage effect.
2016-08-20
2016-07-14
4m, 6m and 10m Combi Antenna.
In a Google search I just found an interesting antenna concept for simple antenna capable of running 4, 6 and 10m.
The antenna is essentially a 10m dipole (can be horizontal or vertical) fed by two lengths of twin-lead cable in series, (from the antenna feed point to the coax) 86cm 450ohm and 295cm 300ohm, fed directly (or via a 1:1 balun) into a 50ohm coax cable. The antenna in itself is 2 pieces of wire, each 258cm long (essentially a 10m dipole antenna). The antenna is a relative of the G5RV type, though not identical.
The gain on 10m is, of course 0dBd, on 6m the antenna probably has a gain of 1 - 1.5dBd, and on 4m it is an Extended double Zepp (2x5/8), and the expected gain is around 3dBd. Sounds to me like a neat compromise for a tri-band antenna.
The antenna is essentially a 10m dipole (can be horizontal or vertical) fed by two lengths of twin-lead cable in series, (from the antenna feed point to the coax) 86cm 450ohm and 295cm 300ohm, fed directly (or via a 1:1 balun) into a 50ohm coax cable. The antenna in itself is 2 pieces of wire, each 258cm long (essentially a 10m dipole antenna). The antenna is a relative of the G5RV type, though not identical.
The gain on 10m is, of course 0dBd, on 6m the antenna probably has a gain of 1 - 1.5dBd, and on 4m it is an Extended double Zepp (2x5/8), and the expected gain is around 3dBd. Sounds to me like a neat compromise for a tri-band antenna.
New Antenna and Cable 6m/2m/70cm.
Yesterday I mounted my V-2000 vertical replacing the old Comet (GP-15, I think), and a new CFD400 cable.
The resonance frequencies :
- a bit low on 2m, but but clearly SWR below 1.4 in the whole band
- nice coverage of the whole 70cm band, less than 1.5 in the useable part of the band
- Decent coverage on 6m, the resonance was adjusted to 50.5 and the antenna is easily <2 in the high end, and <1.5 on essentially all frequencies I will use it for
This is now connected to my 70cm/2m FM rig, and tested on 6m FM. Everything works fine, and it is an improvement above my previous antenna system.
Future improvements of this antenna would be preamps near the antenna, though not in the mast, and possibly a power splitter at the outputs of the preamps, in order to use the antenna for reception on more receivers. The preamp system would then be after approx 8m cable and a triplexer. The preamps should be controlled per band, and that will take a while to design and construct, including some programming, sequencers, the preamps per se, and getting some useable coax relays.
Update : The cable is now connected to a MX62 diplexer, sending the 2m/70cm signals to the VHF/UHF rig, and the 6m signal to the IC7300.
This antenna, at the height it is, is better than the R6000 in its current position on the 6m band, so until the R6000 is raised to a higher position the V2000 will be my 6m antenna.
The resonance frequencies :
- a bit low on 2m, but but clearly SWR below 1.4 in the whole band
- nice coverage of the whole 70cm band, less than 1.5 in the useable part of the band
- Decent coverage on 6m, the resonance was adjusted to 50.5 and the antenna is easily <2 in the high end, and <1.5 on essentially all frequencies I will use it for
This is now connected to my 70cm/2m FM rig, and tested on 6m FM. Everything works fine, and it is an improvement above my previous antenna system.
Future improvements of this antenna would be preamps near the antenna, though not in the mast, and possibly a power splitter at the outputs of the preamps, in order to use the antenna for reception on more receivers. The preamp system would then be after approx 8m cable and a triplexer. The preamps should be controlled per band, and that will take a while to design and construct, including some programming, sequencers, the preamps per se, and getting some useable coax relays.
Update : The cable is now connected to a MX62 diplexer, sending the 2m/70cm signals to the VHF/UHF rig, and the 6m signal to the IC7300.
This antenna, at the height it is, is better than the R6000 in its current position on the 6m band, so until the R6000 is raised to a higher position the V2000 will be my 6m antenna.
2016-07-07
4m and 6m Antennas
At the beginning of the sporadic E season I built a simple ground plane for 4 and 4m, just using a 6m fibre glass telescopic fishing pole and a bit of wire. The antenna works fairly well on 6 and less well on 4m, mostly due to its low height - the top of the antenna for 4m is only slightly over 5m above ground, so shaded by houses and trees.
The pole influenced the antenna considerably, and I was very happy to have my antenna analyzer when cutting it to the bands.
This antenna has worked about 40 countries on 6m, and 5 on 4m.
On 6m it operates a bit better than the R6000 at 3m height.
It was time for a better 4m antenna for local (FM) and a minimum amount of DX, mostly sporadic E. I decided to use a Sirio CX4 which is an end fed half wave antenna. The 10m half wave came down and the CX4 was raised to about 6m (feed point for the half wave about 7m. As expected this works much better than the low ground plane.
For working local stations in SSB, where most are running with horizontal antennas, I need to mount some kind of horizontal antenna myself. I am considering initially to make two dipoles or delta loops for operation in different directions, just to get it running. More elaborate antennas will have to come later.
Now, what to do about 6m ? I want to raise the feed point of the R-6000 to about 7.5m, and that should put the 6m part of the antenna a bit further from the trees around it, giving a better 6m (and 10m) range. On 6m some horizontal antenna is needed, and, again, I consider starting with 2 dipoles or delta loop antennas. A simple "V" shaped horizontal dipole could provide some degree of omnidirectional radiation, though.
For an omnidirectional antenna a "Squalo" (square halo), or a "Big Wheel" could work, or two "double quad"elements at 90 deg. could be fed in 90 deg phase difference, providing a modest gain.
I would like to generate some more gain on 4 and 6, and some kind of phased arrays for fixed favourite directions are in my thoughts. Older hams may be familiar with the "Lazy H" antenna which has a bi-directional gain of about 6dBd. This antenna can be fed with open line feeder and a tuner, making the same antenna suitable for both the 4 and 6m bands. There are other options, and they will be explored.
For now the 4m antenna is operational, and I am often QRV on 70.450MHz FM, and sometimes around 70.200 SSB or CW.
The pole influenced the antenna considerably, and I was very happy to have my antenna analyzer when cutting it to the bands.
This antenna has worked about 40 countries on 6m, and 5 on 4m.
On 6m it operates a bit better than the R6000 at 3m height.
It was time for a better 4m antenna for local (FM) and a minimum amount of DX, mostly sporadic E. I decided to use a Sirio CX4 which is an end fed half wave antenna. The 10m half wave came down and the CX4 was raised to about 6m (feed point for the half wave about 7m. As expected this works much better than the low ground plane.
For working local stations in SSB, where most are running with horizontal antennas, I need to mount some kind of horizontal antenna myself. I am considering initially to make two dipoles or delta loops for operation in different directions, just to get it running. More elaborate antennas will have to come later.
Now, what to do about 6m ? I want to raise the feed point of the R-6000 to about 7.5m, and that should put the 6m part of the antenna a bit further from the trees around it, giving a better 6m (and 10m) range. On 6m some horizontal antenna is needed, and, again, I consider starting with 2 dipoles or delta loop antennas. A simple "V" shaped horizontal dipole could provide some degree of omnidirectional radiation, though.
For an omnidirectional antenna a "Squalo" (square halo), or a "Big Wheel" could work, or two "double quad"elements at 90 deg. could be fed in 90 deg phase difference, providing a modest gain.
I would like to generate some more gain on 4 and 6, and some kind of phased arrays for fixed favourite directions are in my thoughts. Older hams may be familiar with the "Lazy H" antenna which has a bi-directional gain of about 6dBd. This antenna can be fed with open line feeder and a tuner, making the same antenna suitable for both the 4 and 6m bands. There are other options, and they will be explored.
For now the 4m antenna is operational, and I am often QRV on 70.450MHz FM, and sometimes around 70.200 SSB or CW.
2016-06-25
R6000 antenna - Initial Results
The R-6000 antenna has been assembled and is in a temporary position with the feed point about 3m above ground.
Initial results show that CW calls to DX stations often are answered after up to 3 calls. Not bad for a low hanging vertical antenna.
Of course, almost all sporadic E propagation vanished the day the antenna was mounted, so the higher bands have been very quiet. On 20 and 17m, however 5 continents have been worked without much difficulty, despite the low solar activity showing the HF bands in rather poor shape.
The antenna is quite visible due to the multiple radiator rods, so some test for losses of "camouflage paint" (yes, green/brown) with another antenna is in order, before mounting the antenna in a more permanent position (higher feedpoint, about 6 - 7 m high, but somewhat better shielded from view).
The 3 m height was the best we could do with only two people. The higher position requires up to 5 people, some for holding guy wires ...
On the higher bands, 10 and 6m, the actively radiating piece of the antenna is shielded by nearby trees, so the results will be modest until the higher feed point has been achieved.
Here are two late afternoon pics from two different angles. First from the corner of the garden, (street view, rather inconspicuous), and the second from near a neighbour (much more visible).
In the morning light the antenna will be like a shining beacon. This is why I want to disguise the antenna a bit.
Initial results show that CW calls to DX stations often are answered after up to 3 calls. Not bad for a low hanging vertical antenna.
Of course, almost all sporadic E propagation vanished the day the antenna was mounted, so the higher bands have been very quiet. On 20 and 17m, however 5 continents have been worked without much difficulty, despite the low solar activity showing the HF bands in rather poor shape.
The antenna is quite visible due to the multiple radiator rods, so some test for losses of "camouflage paint" (yes, green/brown) with another antenna is in order, before mounting the antenna in a more permanent position (higher feedpoint, about 6 - 7 m high, but somewhat better shielded from view).
The 3 m height was the best we could do with only two people. The higher position requires up to 5 people, some for holding guy wires ...
On the higher bands, 10 and 6m, the actively radiating piece of the antenna is shielded by nearby trees, so the results will be modest until the higher feed point has been achieved.Here are two late afternoon pics from two different angles. First from the corner of the garden, (street view, rather inconspicuous), and the second from near a neighbour (much more visible).
In the morning light the antenna will be like a shining beacon. This is why I want to disguise the antenna a bit.
2016-06-07
R6000 antenna.
The package with the Cushcraft R6000 antenna arrived some time ago, and the unpacking and assembly has started.
Parts 1 and 2 Base assembly, radial rings and matching network :
Part 1 took a few hours, because some parts look a lot alike, screws with only a slightly different length, a few things did not quite look like the drawings and description.
a) The radial ring was supposed to slide over the insulator, but the screws holding the insulator had already been mounted, so they had to be removed before sliding the radial ring into place, then put into place again.
The radials have not yet been mounted for more convenience of making the radiator assembly, it says in the description that the radials can be mounted at any time during the assembly process .
The upper matching network bracket was described having to be mounted tight against the fiberglass insulator. That is not possible, given the assembly as it is, and is not in accordance with the accompanying drawings (showing a short distance between the two) .
Updates to follow :
Radiator assembly, base clamp assembly and mast mounting, then testing the antenna for correct adjustment, and readjustment, if necessary.
Parts 1 and 2 Base assembly, radial rings and matching network :
Part 1 took a few hours, because some parts look a lot alike, screws with only a slightly different length, a few things did not quite look like the drawings and description.
a) The radial ring was supposed to slide over the insulator, but the screws holding the insulator had already been mounted, so they had to be removed before sliding the radial ring into place, then put into place again.
The radials have not yet been mounted for more convenience of making the radiator assembly, it says in the description that the radials can be mounted at any time during the assembly process .
The upper matching network bracket was described having to be mounted tight against the fiberglass insulator. That is not possible, given the assembly as it is, and is not in accordance with the accompanying drawings (showing a short distance between the two) .
Updates to follow :
Radiator assembly, base clamp assembly and mast mounting, then testing the antenna for correct adjustment, and readjustment, if necessary.
2016-04-22
IC-7300 First Impressions.
Having worked with a 7600, and also with a 7100, for a while, and being very happy with that, I reacted on the very favourable reviews of the new IC-7300, and I now have one.
The IC-7300 is the first Amateur radio station by the big 3 Japanese manufactures, being a direct sampling, stand alone SDR radio. I have been looking through various reviews by amateurs having the transceiver before me, and I have not seen *any* negative reviews. Minor nitpicks, but absolutely nothing serious. Given the price point of this radio it looked like a very favourable purchase, despite it being this early in the life time of the transceiver.
I emptied the purse and got one.
First of all the noticeable thing that the 7600 does, and the 7300 does not : Dual reception. This is something that I have not yet used much, so I am probably not going to miss it much.
Then a few things that the 7300 does, that the 7600 does not :
1) 70MHz. This was high on my wish list for a multimode transceiver. Yes, the IC-7100 does 4m (and 2m/70cm), but that one does not have the *very practical* waterfall spectrum display.
2) The built-in antenna tuner (OK, matching circuit) has an "Emergency mode" where, at the price of reduced output power (50%) the tuning range is considerably increased. This can be very convenient with portable operation, where cables are usually shorter, and therefore less lossy.
3) The spectrum scope : The waterfall and spectrum scope is *very fast*, it is possible to "read" CW at slow to moderate speeds, and the signals look much cleaner (narrower) than on the 7600.
4) 472kHz : The radio has been opened for the full TX range, since I want to be able to work on the 5MHz band, and I tested, and found that it actually has some RF output on 472MHz. Something that I never detected on my 7600, or any other radio I have owned. It look like I should try to make some kind of antenna for this band, and for 160m, although, given the size of my garden, and the modest antenna height possible, my expectations are not very high. Thinking of it, I should probably check the output on 472 for spectral purity, I might need a (low pass) filter before I start transmitting serious power on the band.
Operation of the 7300 is in between the 7100 and the 7600. It has a few more dedicated buttons than the 7100 (which uses the touch display extensively), and some of the 7600 dedicated buttons and controls have been squeezed into a multi-function knob and the use of the touch screen. All in all, having used it a few days, my only complaint is that the band switching and the band stacking registers need double the operations when compared to the 7600 (but same as the 7100).
Modulation quality is excellent, right out of the box, I have yet to make any adjustments. I might use the tone controls a bit, but, working mostly CW, I have not yet done much about that.
All in all, the operation with the 7300 is easy, although I have only scratched the surface of its possibilities. I am very happy using this in my "living room shack".
The price is less than half the price of the 7600, and still lower than that of the 7100. Impressive !
Now I need more antennas ;)
I believe this transceiver is only the first of many direct sampling stand-alone radios. Icom has impressed me quite a bit with this one. Come on, Yaesu, Kenwood and others ...
The IC-7300 is the first Amateur radio station by the big 3 Japanese manufactures, being a direct sampling, stand alone SDR radio. I have been looking through various reviews by amateurs having the transceiver before me, and I have not seen *any* negative reviews. Minor nitpicks, but absolutely nothing serious. Given the price point of this radio it looked like a very favourable purchase, despite it being this early in the life time of the transceiver.
I emptied the purse and got one.
First of all the noticeable thing that the 7600 does, and the 7300 does not : Dual reception. This is something that I have not yet used much, so I am probably not going to miss it much.
Then a few things that the 7300 does, that the 7600 does not :
1) 70MHz. This was high on my wish list for a multimode transceiver. Yes, the IC-7100 does 4m (and 2m/70cm), but that one does not have the *very practical* waterfall spectrum display.
2) The built-in antenna tuner (OK, matching circuit) has an "Emergency mode" where, at the price of reduced output power (50%) the tuning range is considerably increased. This can be very convenient with portable operation, where cables are usually shorter, and therefore less lossy.
3) The spectrum scope : The waterfall and spectrum scope is *very fast*, it is possible to "read" CW at slow to moderate speeds, and the signals look much cleaner (narrower) than on the 7600.
4) 472kHz : The radio has been opened for the full TX range, since I want to be able to work on the 5MHz band, and I tested, and found that it actually has some RF output on 472MHz. Something that I never detected on my 7600, or any other radio I have owned. It look like I should try to make some kind of antenna for this band, and for 160m, although, given the size of my garden, and the modest antenna height possible, my expectations are not very high. Thinking of it, I should probably check the output on 472 for spectral purity, I might need a (low pass) filter before I start transmitting serious power on the band.
Operation of the 7300 is in between the 7100 and the 7600. It has a few more dedicated buttons than the 7100 (which uses the touch display extensively), and some of the 7600 dedicated buttons and controls have been squeezed into a multi-function knob and the use of the touch screen. All in all, having used it a few days, my only complaint is that the band switching and the band stacking registers need double the operations when compared to the 7600 (but same as the 7100).
Modulation quality is excellent, right out of the box, I have yet to make any adjustments. I might use the tone controls a bit, but, working mostly CW, I have not yet done much about that.
All in all, the operation with the 7300 is easy, although I have only scratched the surface of its possibilities. I am very happy using this in my "living room shack".
The price is less than half the price of the 7600, and still lower than that of the 7100. Impressive !
Now I need more antennas ;)
I believe this transceiver is only the first of many direct sampling stand-alone radios. Icom has impressed me quite a bit with this one. Come on, Yaesu, Kenwood and others ...
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