|
Wellbrook ALA1530+ Vs. ALA100?
Do you currently use a longwire or dipole or have the real estate for one?
Have you been considering the ALA1530+ instead? I exchanged emails with Wellbrook about using the ALA100 with my current 70M fullwave Horizontal loop. About Horizontal loops http://www.cebik.com/wire/hl.html http://www.cebik.com/fdim/atl1.html http://www.cebik.com/wire/horloop.html About ALA100 http://www.wellbrook.uk.com/ALA100b.html The ALA100 will allow me to use a coax feeder instead of the noise prone 450ohm ladder-line and dispense with the antenna tuner/matchbox. Per Wellbrook, "You may also find that a smaller vertical loop with ALA100 will give better directivity for MW plus very high gain at HF. The ALA100 will out perform the ALA1530+ , because the loop area is much larger." So if you are considering a ALA1530+ and are currently occupying real estate with a long-wire or dipole, you may consider joining the ends with the ALA100 for a loop in either the horizontal or vertical plane. Here's to the '06/'07 DXing season! Post your logs and good luck. |
Wellbrook ALA1530+ Vs. ALA100?
Seeing-I-dawg wrote: Do you currently use a longwire or dipole or have the real estate for one? Have you been considering the ALA1530+ instead? I exchanged emails with Wellbrook about using the ALA100 with my current 70M fullwave Horizontal loop. About Horizontal loops http://www.cebik.com/wire/hl.html http://www.cebik.com/fdim/atl1.html http://www.cebik.com/wire/horloop.html About ALA100 http://www.wellbrook.uk.com/ALA100b.html The ALA100 will allow me to use a coax feeder instead of the noise prone 450ohm ladder-line and dispense with the antenna tuner/matchbox. Per Wellbrook, "You may also find that a smaller vertical loop with ALA100 will give better directivity for MW plus very high gain at HF. The ALA100 will out perform the ALA1530+ , because the loop area is much larger." So if you are considering a ALA1530+ and are currently occupying real estate with a long-wire or dipole, you may consider joining the ends with the ALA100 for a loop in either the horizontal or vertical plane. Here's to the '06/'07 DXing season! Post your logs and good luck. First, please understand and accept that I have nothing against the Wellbrook company or thier products. Their web page has clearly helped many newbie SWL learn how to errect a "long" wire antenna. And many people swear by all of their loops. However, my experience suggests loops may not be the do all end all. For a alternative perspective please read the research by Dallas Lanford at http://www.kongsfjord.no/ "Measurements of Some Antennas Signal to Man Made Noise Ratios" Every situation is different. And the guy I traded theALA 1530 to loves it. Perhaps under extreme noise situations loops are better. My recent experiments mirrored Dallas' experiences. My "shack" is still disassembled. I hope to have it up and running by the weekend. 2 days of rain really messed with my plans. Terry |
Wellbrook ALA1530+ Vs. ALA100?
In article .com,
"Steve" wrote: wrote: Seeing-I-dawg wrote: Do you currently use a longwire or dipole or have the real estate for one? Have you been considering the ALA1530+ instead? I exchanged emails with Wellbrook about using the ALA100 with my current 70M fullwave Horizontal loop. About Horizontal loops http://www.cebik.com/wire/hl.html http://www.cebik.com/fdim/atl1.html http://www.cebik.com/wire/horloop.html About ALA100 http://www.wellbrook.uk.com/ALA100b.html The ALA100 will allow me to use a coax feeder instead of the noise prone 450ohm ladder-line and dispense with the antenna tuner/matchbox. Per Wellbrook, "You may also find that a smaller vertical loop with ALA100 will give better directivity for MW plus very high gain at HF. The ALA100 will out perform the ALA1530+ , because the loop area is much larger." So if you are considering a ALA1530+ and are currently occupying real estate with a long-wire or dipole, you may consider joining the ends with the ALA100 for a loop in either the horizontal or vertical plane. Here's to the '06/'07 DXing season! Post your logs and good luck. First, please understand and accept that I have nothing against the Wellbrook company or thier products. Their web page has clearly helped many newbie SWL learn how to errect a "long" wire antenna. And many people swear by all of their loops. However, my experience suggests loops may not be the do all end all. For a alternative perspective please read the research by Dallas Lanford at http://www.kongsfjord.no/ "Measurements of Some Antennas Signal to Man Made Noise Ratios" Every situation is different. And the guy I traded theALA 1530 to loves it. Perhaps under extreme noise situations loops are better. My recent experiments mirrored Dallas' experiences. My "shack" is still disassembled. I hope to have it up and running by the weekend. 2 days of rain really messed with my plans. I have an open mind on this issue. I use one of the Wellbrook loops and I like it, but I'm perfectly prepared to believe that a small active vertical can be just as quiet. What generates confusion about this issue are the conflicting reports one hears and even the conflicting experimental results one reads about. I visited the http://www.kongsfjord.no site and found it very interesting. However, if you look at some of the reviews available on the Wellbrook website, you'll see different tests and comparisons that yield results that are much more favorable to the Wellbrooks. There may well be something wrong with the tests and comparisons carried out in those reviews. I don't see anything obviously suspect about them, but I don't have the technical expertise that some of the folks in this group have. In any case, I think it's this kind of data that accounts for the reputation the Wellbrook loops have as being extremely quiet antennas. One problem of post in a public news group is that at times I feel like I'm talking to a brick wall. Most peoples experience in high noise areas will favor a loop antenna over a dipole for locally picked up noise. This is an expected theoretical result of local induction fields affecting loop and dipole antennas. The IP2 and IP3 differences in the active antennas are due to the amplifier design not the antenna. -- Telamon Ventura, California |
Wellbrook ALA1530+ Vs. ALA100?
Telamon wrote: In article .com, "Steve" wrote: wrote: Seeing-I-dawg wrote: Do you currently use a longwire or dipole or have the real estate for one? Have you been considering the ALA1530+ instead? I exchanged emails with Wellbrook about using the ALA100 with my current 70M fullwave Horizontal loop. About Horizontal loops http://www.cebik.com/wire/hl.html http://www.cebik.com/fdim/atl1.html http://www.cebik.com/wire/horloop.html About ALA100 http://www.wellbrook.uk.com/ALA100b.html The ALA100 will allow me to use a coax feeder instead of the noise prone 450ohm ladder-line and dispense with the antenna tuner/matchbox. Per Wellbrook, "You may also find that a smaller vertical loop with ALA100 will give better directivity for MW plus very high gain at HF. The ALA100 will out perform the ALA1530+ , because the loop area is much larger." So if you are considering a ALA1530+ and are currently occupying real estate with a long-wire or dipole, you may consider joining the ends with the ALA100 for a loop in either the horizontal or vertical plane. Here's to the '06/'07 DXing season! Post your logs and good luck. First, please understand and accept that I have nothing against the Wellbrook company or thier products. Their web page has clearly helped many newbie SWL learn how to errect a "long" wire antenna. And many people swear by all of their loops. However, my experience suggests loops may not be the do all end all. For a alternative perspective please read the research by Dallas Lanford at http://www.kongsfjord.no/ "Measurements of Some Antennas Signal to Man Made Noise Ratios" Every situation is different. And the guy I traded theALA 1530 to loves it. Perhaps under extreme noise situations loops are better. My recent experiments mirrored Dallas' experiences. My "shack" is still disassembled. I hope to have it up and running by the weekend. 2 days of rain really messed with my plans. I have an open mind on this issue. I use one of the Wellbrook loops and I like it, but I'm perfectly prepared to believe that a small active vertical can be just as quiet. What generates confusion about this issue are the conflicting reports one hears and even the conflicting experimental results one reads about. I visited the http://www.kongsfjord.no site and found it very interesting. However, if you look at some of the reviews available on the Wellbrook website, you'll see different tests and comparisons that yield results that are much more favorable to the Wellbrooks. There may well be something wrong with the tests and comparisons carried out in those reviews. I don't see anything obviously suspect about them, but I don't have the technical expertise that some of the folks in this group have. In any case, I think it's this kind of data that accounts for the reputation the Wellbrook loops have as being extremely quiet antennas. - One problem of post in a public news group is - that at times I feel like I'm talking to a brick wall. Telamon - You Just Keep-On Writing : Cause This Brick Wall Is Listening ! ~ RHF - Most peoples experience in high noise areas will favor - a loop antenna over a dipole for locally picked up noise. OK ! - This is an expected theoretical result of local induction - fields affecting loop and dipole antennas. OK ! - The IP2 and IP3 differences in the active antennas - are due to the amplifier design not the antenna. The ablity to 'rotate' a small Loop Antenna to Null-Out a Local Offending Radio Station {Signal Source} does have to be factored into the practical {use} equation. -vice- A small Vertical Whip Antenna {Omni-Directional} : Given that the Amplifier used with both Antennas has the same characteristics. However - The Practical {Use} Equation {Societal Factoring} may make the 'near invisibility' of the Small {Short-and-Thin} Vertical Whip Antenna the only realistic choice for an Antenna by a Shortwave Listener (SWL) "When NO Antenna Is Allowed." what antenna ? i don't see an antenna : i ain't got no stinking antenna ~ RHF |
Wellbrook ALA1530+ Vs. ALA100?
wrote in message oups.com... Seeing-I-dawg wrote: Do you currently use a longwire or dipole or have the real estate for one? Have you been considering the ALA1530+ instead? I exchanged emails with Wellbrook about using the ALA100 with my current 70M fullwave Horizontal loop. About Horizontal loops http://www.cebik.com/wire/hl.html http://www.cebik.com/fdim/atl1.html http://www.cebik.com/wire/horloop.html About ALA100 http://www.wellbrook.uk.com/ALA100b.html The ALA100 will allow me to use a coax feeder instead of the noise prone 450ohm ladder-line and dispense with the antenna tuner/matchbox. Per Wellbrook, "You may also find that a smaller vertical loop with ALA100 will give better directivity for MW plus very high gain at HF. The ALA100 will out perform the ALA1530+ , because the loop area is much larger." So if you are considering a ALA1530+ and are currently occupying real estate with a long-wire or dipole, you may consider joining the ends with the ALA100 for a loop in either the horizontal or vertical plane. Here's to the '06/'07 DXing season! Post your logs and good luck. First, please understand and accept that I have nothing against the Wellbrook company or thier products. Their web page has clearly helped many newbie SWL learn how to errect a "long" wire antenna. And many people swear by all of their loops. However, my experience suggests loops may not be the do all end all. For a alternative perspective please read the research by Dallas Lanford at http://www.kongsfjord.no/ "Measurements of Some Antennas Signal to Man Made Noise Ratios" Every situation is different. And the guy I traded theALA 1530 to loves it. Perhaps under extreme noise situations loops are better. My recent experiments mirrored Dallas' experiences. My "shack" is still disassembled. I hope to have it up and running by the weekend. 2 days of rain really messed with my plans. Terry Terry, this post wasn't intended as an addendum to my previous post to you about horizontal loops. I don't/can't dispute the claims about verticals Vs. loops regarding noise. Generally, a vertical antenna is ideal for DXing since its main "lobe" is towards the horizon (in all directions). But I know you knew that. Could that account for the difference in S/MMN ratio in the Kongsfjord comparison? The two main practical advantages of loops is steerability or nulling with relatively small loops and inherently broadbanded performance with relatively large (full wave) loops. The Wellbrook ALA1530+ claims both - broadband performance using a broadband amplifier and steerability using a small "shielded" loop. The ALA1530+ design is different from the ALA100 in that the ALA1530+ "loop" is inside an aluminum tube/shield. Alegedly this shield(?) rejects the nearby Electric-field which supposedly contains the noise component and amplifies the Magnetic-field which supposedly does not contain the noise [Electro-Magnetic wave = RF]. The ALA100 wire antenna component has no shield so how can it reject nearby Electric-fields containing noise? Additionally, in the Kongsfjord power line comparison (45Ft vertical Vs. Loop) the vertical's main lobe is at the horizon (under the powerline). The lobes of the loop are very much like that of a dipole (above the horizon) - more closely aimed at the powerline. Therefor, I think the Kongsfjord comparison is missplaced. But I am not versed with the noise argument related to loops Vs. verticals. My point to my original post in this thread was that if you already have a dipole or longwire (which is inherently NOT broadbanded) you can use the ALA100 to convert them into a loop. The Wellbrook ALA100 product is simply a broadband amplifier (I suspect similiar to the 1530). It does not include any "antenna" or coax. You supply the antenna wire yourself - an existing dipole or longwire folded into some resemblance to a large broadbanded loop. The shape is not critical as long as the wires are not too close. Converting a dipole or longwire into a broadbanded loop and adding a broadbanded amplifier like the ALA100 seems like a good idea. Although the ALA100 was meant to be used with a relatively medium sized rotatable vertical loop, http://www.wellbrook.uk.com/ALA100b.html Wellbrook's email in essence said it will work with any reasonably sized loop oriented in any plane - vertically or horizontally. My antenna goal is to have one antenna and to squeeze as much performance out of it on as many frequencies (500KHz-30MHz) as possible. That, my friend, can be most closely accomplished with a large loop. However, I am intriqed by the 15ft vertical that is diagramed at the Kongsfjord noise measurments link. There are no ideal antennas. Just antennas with ideal applications. |
Wellbrook ALA1530+ Vs. ALA100?
Terry,
Please read the last paragraph of this 1991 paper: http://www.kongsfjord.no/dl/Antennas...ensitivity.pdf "Seeing-I-dawg" wrote in message ... wrote in message oups.com... Seeing-I-dawg wrote: Do you currently use a longwire or dipole or have the real estate for one? Have you been considering the ALA1530+ instead? I exchanged emails with Wellbrook about using the ALA100 with my current 70M fullwave Horizontal loop. About Horizontal loops http://www.cebik.com/wire/hl.html http://www.cebik.com/fdim/atl1.html http://www.cebik.com/wire/horloop.html About ALA100 http://www.wellbrook.uk.com/ALA100b.html The ALA100 will allow me to use a coax feeder instead of the noise prone 450ohm ladder-line and dispense with the antenna tuner/matchbox. Per Wellbrook, "You may also find that a smaller vertical loop with ALA100 will give better directivity for MW plus very high gain at HF. The ALA100 will out perform the ALA1530+ , because the loop area is much larger." So if you are considering a ALA1530+ and are currently occupying real estate with a long-wire or dipole, you may consider joining the ends with the ALA100 for a loop in either the horizontal or vertical plane. Here's to the '06/'07 DXing season! Post your logs and good luck. First, please understand and accept that I have nothing against the Wellbrook company or thier products. Their web page has clearly helped many newbie SWL learn how to errect a "long" wire antenna. And many people swear by all of their loops. However, my experience suggests loops may not be the do all end all. For a alternative perspective please read the research by Dallas Lanford at http://www.kongsfjord.no/ "Measurements of Some Antennas Signal to Man Made Noise Ratios" Every situation is different. And the guy I traded theALA 1530 to loves it. Perhaps under extreme noise situations loops are better. My recent experiments mirrored Dallas' experiences. My "shack" is still disassembled. I hope to have it up and running by the weekend. 2 days of rain really messed with my plans. Terry Terry, this post wasn't intended as an addendum to my previous post to you about horizontal loops. I don't/can't dispute the claims about verticals Vs. loops regarding noise. Generally, a vertical antenna is ideal for DXing since its main "lobe" is towards the horizon (in all directions). But I know you knew that. Could that account for the difference in S/MMN ratio in the Kongsfjord comparison? The two main practical advantages of loops is steerability or nulling with relatively small loops and inherently broadbanded performance with relatively large (full wave) loops. The Wellbrook ALA1530+ claims both - broadband performance using a broadband amplifier and steerability using a small "shielded" loop. The ALA1530+ design is different from the ALA100 in that the ALA1530+ "loop" is inside an aluminum tube/shield. Alegedly this shield(?) rejects the nearby Electric-field which supposedly contains the noise component and amplifies the Magnetic-field which supposedly does not contain the noise [Electro-Magnetic wave = RF]. The ALA100 wire antenna component has no shield so how can it reject nearby Electric-fields containing noise? Additionally, in the Kongsfjord power line comparison (45Ft vertical Vs. Loop) the vertical's main lobe is at the horizon (under the powerline). The lobes of the loop are very much like that of a dipole (above the horizon) - more closely aimed at the powerline. Therefor, I think the Kongsfjord comparison is missplaced. But I am not versed with the noise argument related to loops Vs. verticals. My point to my original post in this thread was that if you already have a dipole or longwire (which is inherently NOT broadbanded) you can use the ALA100 to convert them into a loop. The Wellbrook ALA100 product is simply a broadband amplifier (I suspect similiar to the 1530). It does not include any "antenna" or coax. You supply the antenna wire yourself - an existing dipole or longwire folded into some resemblance to a large broadbanded loop. The shape is not critical as long as the wires are not too close. Converting a dipole or longwire into a broadbanded loop and adding a broadbanded amplifier like the ALA100 seems like a good idea. Although the ALA100 was meant to be used with a relatively medium sized rotatable vertical loop, http://www.wellbrook.uk.com/ALA100b.html Wellbrook's email in essence said it will work with any reasonably sized loop oriented in any plane - vertically or horizontally. My antenna goal is to have one antenna and to squeeze as much performance out of it on as many frequencies (500KHz-30MHz) as possible. That, my friend, can be most closely accomplished with a large loop. However, I am intriqed by the 15ft vertical that is diagramed at the Kongsfjord noise measurments link. There are no ideal antennas. Just antennas with ideal applications. |
Wellbrook ALA1530+ Vs. ALA100?
Please read the last paragraph of this 1991 paper: http://www.kongsfjord.no/dl/Antennas...ensitivity.pdf Generally, a vertical antenna is ideal for DXing since its main "lobe" is towards the horizon (in all directions). But I know you knew that. Could that account for the difference in S/MMN ratio in the Kongsfjord comparison? .... Additionally, in the Kongsfjord power line comparison (45Ft vertical Vs. Loop) the vertical's main lobe is at the horizon (under the powerline). The lobes of the loop are very much like that of a dipole (above the horizon) - more closely aimed at the powerline. Addition part II: The powerline noise is horizontally polarized while a vertical antenna is vertically polarized. The noise was 90 degrees out of phase [typically a difference of what? 6db?]. Thus the vertical antenna in this situation was at a distinct advantage. Out of phase and major lobe pointed away from the powerline. A square loop, as is the ALA100 loop, is both horizontally and vertically polarized. Thus more sensitive to receiving the horizontally polarized powerline noise compared to a vertical antenna. |
Wellbrook ALA1530+ Vs. ALA100?
Here's another idea:
Custom made, 5ft square, rotatable loop using Wellbrook ALA-100 amp "...so far it looks to be a fine replacement for my 700 ft. NW Beverage antenna..." http://sdr-1000.blogspot.com/2006/07...0-antenna.html __________________________________________________ ____________ "Seeing-I-dawg" wrote in message ... Do you currently use a longwire or dipole or have the real estate for one? Have you been considering the ALA1530+ instead? I exchanged emails with Wellbrook about using the ALA100 with my current 70M fullwave Horizontal loop. About Horizontal loops http://www.cebik.com/wire/hl.html http://www.cebik.com/fdim/atl1.html http://www.cebik.com/wire/horloop.html About ALA100 http://www.wellbrook.uk.com/ALA100b.html The ALA100 will allow me to use a coax feeder instead of the noise prone 450ohm ladder-line and dispense with the antenna tuner/matchbox. Per Wellbrook, "You may also find that a smaller vertical loop with ALA100 will give better directivity for MW plus very high gain at HF. The ALA100 will out perform the ALA1530+ , because the loop area is much larger." So if you are considering a ALA1530+ and are currently occupying real estate with a long-wire or dipole, you may consider joining the ends with the ALA100 for a loop in either the horizontal or vertical plane. Here's to the '06/'07 DXing season! Post your logs and good luck. |
Wellbrook ALA1530+ Vs. ALA100?
On Oct 4, 6:36 pm, "Seeing-I-dawg" wrote: Terry, Please read the last paragraph of this 1991 paper:http://www.kongsfjord.no/dl/Antennas...ensitivity.pdf Yep, the directivity of a loop is what the "magic" is all about. Dallas' active dipole exhibited better, as in a better null, directivity from 100KHz (loran) to CB. A good buddy ratchet mouth about 3 miles from me makes a great far field test signal. The Feb 1955 "Wireless Engineer" paper by J.S.Belrose gives some very usefull info on loop. I am not saying loops have no place. Jeff, the guy I traded the wellbrook to, loves it. In his RF hell it works better then anyother antenna he has tried. Once I get the shack rebuilt I intend to take my latest version of Dallas' active dipole there to see if the tighter null will help. I plan on building the WL1030 that RHF mentioned. Martinn Hagg's design look workable. I have major doubts about wide band OpAmps in a harsh RF task, but I am willing to give it a try. I suspect that Dallas' Ultra Linear Amplifier will work as well as the Wellbrook loop maker. And it would be a lot less expensive. The Kiwa amp version 2, should also work. It will need a ?1:! broadband transformer but it is a pretty good amp. The Belrose paper explained why the 2 different heads I have for my McKay-Dymek DA5 behave so differently under temperature extremes. The unit that performs the best under wide, 100F to -20F temperature swings has a slot lengthwise to the hollow center. I have been in a heated conversation with some SWL aquantances here in the central KY area about how long a "long wire" should be. And at what length does it start degrading radio performance. Most SWL or hams, or even professional RF engineers, either don' know, or refuse to think about, the effects too much signal can cause. Front ends and first mixers behave very badly with 1dB to many. I envy DXace becuase he clearly has a superior RF location with a low enough background RF to degrade his R8B. Sadly around here, anything over 100' is more likely to cause problems then help you dig out the really weak DX. Jeff, he lives in a downtown Lexington condo, has had nasty experiences with out of band overload causing all sorts of receiver misbehavoir. And he has an AOR7030, not the plus version. Terry |
Wellbrook ALA1530+ Vs. ALA100?
Seeing-I-dawg wrote: Here's another idea: Custom made, 5ft square, rotatable loop using Wellbrook ALA-100 amp "...so far it looks to be a fine replacement for my 700 ft. NW Beverage antenna..." http://sdr-1000.blogspot.com/2006/07...0-antenna.html __________________________________________________ ____________ "Seeing-I-dawg" wrote in message ... Do you currently use a longwire or dipole or have the real estate for one? Have you been considering the ALA1530+ instead? I exchanged emails with Wellbrook about using the ALA100 with my current 70M fullwave Horizontal loop. About Horizontal loops http://www.cebik.com/wire/hl.html http://www.cebik.com/fdim/atl1.html http://www.cebik.com/wire/horloop.html About ALA100 http://www.wellbrook.uk.com/ALA100b.html The ALA100 will allow me to use a coax feeder instead of the noise prone 450ohm ladder-line and dispense with the antenna tuner/matchbox. Per Wellbrook, "You may also find that a smaller vertical loop with ALA100 will give better directivity for MW plus very high gain at HF. The ALA100 will out perform the ALA1530+ , because the loop area is much larger." So if you are considering a ALA1530+ and are currently occupying real estate with a long-wire or dipole, you may consider joining the ends with the ALA100 for a loop in either the horizontal or vertical plane. Here's to the '06/'07 DXing season! Post your logs and good luck. Once you have about 50ft on the ALA100, it really cranks. I have mine in a multi-turn loop as well. With 50ft, myAR7030+ needs to switch in the attenuator on local BCB. |
Wellbrook ALA1530+ Vs. ALA100?
You pretty much nailed it. No antenna is ideal. The fun is finding one,
two, three... that work respectably with your gear, your particular RF environment, and your listening goals. That could be anything from a beverage to a rubber duck :-) IM - yech! Outboard filter(s) to knock down the offending station(s) perhaps? Regarding longwires; Why? It will have peaks and valleys in reception across the RF spectrum. Join the ends to make a horizontal loop and that will disappear - linear response. I respect Guy Atkins remarks regarding his dissappointment with the Wellbrook 1530. I have never owned a loop of that size and type and have always been apprehensive about trying it. Noise isn't a huge problem here. If I can replace my 450 ohm ladder-line feed to my horizontal loop with coax (using the ALA100 amp) I may be able to eliminate most of the remaining noise and pick up a db or two (except I can no longer transmit into it). I no longer am a DYI with electronics. I just don't have the time or patience to gather the parts, solder the board and cross my fingers. If someone sells an assembled Dallas amplifier I may bite. I am really getting excited about the software defined radio Guy Atkins uses. After listening to his sound bites on his SDR-1000 blog I have to lock up the credit cards. I would really enjoy attending one of his DXpeditions. EOM wrote in message ups.com... On Oct 4, 6:36 pm, "Seeing-I-dawg" wrote: Terry, Please read the last paragraph of this 1991 paper:http://www.kongsfjord.no/dl/Antennas...ensitivity.pdf Yep, the directivity of a loop is what the "magic" is all about. Dallas' active dipole exhibited better, as in a better null, directivity from 100KHz (loran) to CB. A good buddy ratchet mouth about 3 miles from me makes a great far field test signal. The Feb 1955 "Wireless Engineer" paper by J.S.Belrose gives some very usefull info on loop. I am not saying loops have no place. Jeff, the guy I traded the wellbrook to, loves it. In his RF hell it works better then anyother antenna he has tried. Once I get the shack rebuilt I intend to take my latest version of Dallas' active dipole there to see if the tighter null will help. I plan on building the WL1030 that RHF mentioned. Martinn Hagg's design look workable. I have major doubts about wide band OpAmps in a harsh RF task, but I am willing to give it a try. I suspect that Dallas' Ultra Linear Amplifier will work as well as the Wellbrook loop maker. And it would be a lot less expensive. The Kiwa amp version 2, should also work. It will need a ?1:! broadband transformer but it is a pretty good amp. The Belrose paper explained why the 2 different heads I have for my McKay-Dymek DA5 behave so differently under temperature extremes. The unit that performs the best under wide, 100F to -20F temperature swings has a slot lengthwise to the hollow center. I have been in a heated conversation with some SWL aquantances here in the central KY area about how long a "long wire" should be. And at what length does it start degrading radio performance. Most SWL or hams, or even professional RF engineers, either don' know, or refuse to think about, the effects too much signal can cause. Front ends and first mixers behave very badly with 1dB to many. I envy DXace becuase he clearly has a superior RF location with a low enough background RF to degrade his R8B. Sadly around here, anything over 100' is more likely to cause problems then help you dig out the really weak DX. Jeff, he lives in a downtown Lexington condo, has had nasty experiences with out of band overload causing all sorts of receiver misbehavoir. And he has an AOR7030, not the plus version. Terry |
Wellbrook ALA1530+ Vs. ALA100?
RHF wrote:
However - The Practical {Use} Equation {Societal Factoring} may make the 'near invisibility' of the Small {Short-and-Thin} Vertical Whip Antenna the only realistic choice for an Antenna by a Shortwave Listener (SWL) "When NO Antenna Is Allowed." what antenna ? i don't see an antenna : i ain't got no stinking antenna ~ RHF My 6 DA100E whips and 2 ALA1530s are disguised as bird feeders and bird houses, not because of any restriction but because it makes it neighbor-friendly. loop in foreground and whip in background http://home.att.net/~rhhardin/antenna.jpg Both are supported by 8' ground rods tapped in a few feet; the ALA1530 is on a galvinized pipe slipped over the ground rod, with a floor flange screwed on the bottom so it doesn't sink into the ground, making it rotatable by hand. The coax comes off the outside of the pipe and makes a few turns looped around the pipe for slack, this loop being covered by a stove burner reflector against lawnmower attacks. The bird feeder is supported by the antenna rather than vice versa, incidentally. -- Ron Hardin On the internet, nobody knows you're a jerk. |
Wellbrook ALA1530+ Vs. ALA100?
Seeing-I-dawg wrote: You pretty much nailed it. No antenna is ideal. The fun is finding one, two, three... that work respectably with your gear, your particular RF environment, and your listening goals. That could be anything from a beverage to a rubber duck :-) IM - yech! Outboard filter(s) to knock down the offending station(s) perhaps? Regarding longwires; Why? It will have peaks and valleys in reception across the RF spectrum. Join the ends to make a horizontal loop and that will disappear - linear response. I respect Guy Atkins remarks regarding his dissappointment with the Wellbrook 1530. I have never owned a loop of that size and type and have always been apprehensive about trying it. Noise isn't a huge problem here. If I can replace my 450 ohm ladder-line feed to my horizontal loop with coax (using the ALA100 amp) I may be able to eliminate most of the remaining noise and pick up a db or two (except I can no longer transmit into it). I no longer am a DYI with electronics. I just don't have the time or patience to gather the parts, solder the board and cross my fingers. If someone sells an assembled Dallas amplifier I may bite. I am really getting excited about the software defined radio Guy Atkins uses. After listening to his sound bites on his SDR-1000 blog I have to lock up the credit cards. I would really enjoy attending one of his DXpeditions. EOM Guy Atkins is very lucky to live in what must be one of the quitest RF environments around. My home RF level isn't as bad as I had thought, I know see what real bad RFI is, but at that there is very little I can hear on a AOR7030+, R8B, or a R2000. The first 2 recivers do a much beter job in very crowded band conditions with very strong signlas next to weak ones that I am intereted in. On a "remote" mountain top in eastern KY I enjoyed pushing the AOR to the limits. That quite location showed the difference between a great receiver and a much more modest (R2000) receiver. Perversly better locations deserve better recveivers. Since the local noise floor sets the limit to our reception it makes sense but it does feel odd. I have been busy trying to eliminate, or at least reduce, any unwanted RF noise. Sadly while I have had great success at eliminating the RF noise emitted by/within our home. We got rid of our desk top PCs, tossed the TV and similar steps have reduced my noise floor as much as I can. Too bad I can;t convine my nieghbors to limit thier RFI. I had hoped the Wellbrook ALA 1530 would reduce noise from nearby homes, but either the whole lopp concept is flawed, which I believe, or my in location all the noise is "far field" and a loop won't help. Terry |
Wellbrook ALA1530+ Vs. ALA100?
wrote I had hoped the Wellbrook ALA 1530 would reduce noise from nearby homes, but either the whole lopp concept is flawed, which I believe, or my in location all the noise is "far field" and a loop won't help. Curious that Wellbrook states that the 1530 will operate best when it is about 30ft away from your home and for best MW reception mounted near the ground. It alegedly performs better on SW when mounted up high at the cost of MW reception. Where's that credit card!? LOL |
Wellbrook ALA1530+ Vs. ALA100?
Seeing-I-dawg wrote:
wrote in message oups.com... Seeing-I-dawg wrote: cut My antenna goal is to have one antenna and to squeeze as much performance out of it on as many frequencies (500KHz-30MHz) as possible. That, my friend, can be most closely accomplished with a large loop. However, I am intriqed by the 15ft vertical that is diagramed at the Kongsfjord noise measurments link. cut An inverted L, 15 feet vertical and 30 feet horizontal, works fine too. You can make it longer and higher, or amplify it if you want more signal. Though more sensitive to horizontal polarization then the vertical, the L still beats the ALA 100 by about 10 dB S/MMN in the near field of power lines, just like the vertical. I used verticals for the previous comparisons because those were what I am using currently (verticals give me better phaser performance in the MW band than L's). |
Wellbrook ALA1530+ Vs. ALA100?
|
Wellbrook ALA1530+ Vs. ALA100?
wrote in message ups.com... Guy Atkins is very lucky to live in what must be one of the quitest RF environments around. My home RF level isn't as bad as I had thought, I know see what real bad RFI is, but at that there is very little I can hear on a AOR7030+, R8B, or a R2000. Yes, it's very quiet here in the Pacific NW, with the fewest "thunderstorm days" of any place in the continental USA. In mid-winter, with a Western Beverage antenna at dawn, aimed out over the Pacific Ocean, you'd swear your receiver was defective, or the antenna broken. In these conditions, extremely faint tropical band and foreign (TP) mediumwave signals have a fighting chance to be heard (assuming a top-notch, low noise receiver like a AR7030 or my current fave, the SDR-1000. It was under these mid-winter, dawn enhancement conditions that I heard tantalizing faint signals around 3174 kHz (variable) in the late 1990s, which had all the clues of Indonesian "amatir" stations. Think: Indo college kids back home on holiday or weekend breaks, playing non-stop Indo rock music with flea-powered transmitters, no IDs, often distorted audio, no official "RRI" news at the top of the hour, etc. I've heard enough of the real RRI and RPD Indonesian stations to recognize the Indo amatir (pirate) station. Similarly, I've logged very low power Australian x-band stations such as Radio Brisvaani, the Hindi station on 1701 kHz (Brisbane, Queensland). I'd never have a chance to hear this sort of DX, however, at home in the suburban RF jungle near Seattle-Tacoma. These catches were on coastal DXpeditions, under ideal conditions. I do have pretty low noise levels of the RFI, hash-and-buzz sort at home, due to the underground AC mains. The main problem are the dozen or so MW stations registering S-9+40 to S-9+60 dB on the SDR's (calibrated) signal meter. My local 1 kw'er, 1450 KSUH in Puyallup, is a bit over 1 mile from home. When I had a 700 ft. Beverage antenna aimed at my Asian targets, the antenna unfortunately was oriented right at KSUH, too. The signal on 1450 from that antenna registered -13 dBm, which is, I believe, around S-9+65 dB. This is an example of what the trans-Pacific MW stations need to fight through to be heard in a suburban location like this. So far, I'm finding the Wellbrook ALA 100 on a rotator does just fine for snagging the foreign MW DX that makes it through the RF jungle; a Beverage is no advantage. 73, Guy Atkins Puyallup, WA www.sdr-1000.blogspot.com |
Wellbrook ALA1530+ Vs. ALA100?
Guy is so right about the joys of DXing in a very low noise environment,
such as the Pacific coast Grayland site. I takes a lot of research and running around to find an "ideal" low noise DX site and on our crowded planet they become harder and harder to find. I found such a site in a remote part of our Atlantic coast,Seefontein, miles from the nearest town and miles from the nearest powerline. It's just bliss to have that phenomena that Guy describes: when the noise on the antenna's is so low you start checking to see if in fact they are connected. It is such a joy to hear stations thousand's of miles away waft in over the airwaves as clear as a bell, yet the signal strength is so low it doesn't even move your "S" meter. What a thrill! That's why some of us serious DXer's travel long distances with considerable effort in time and money to enjoy these most favourable DX conditions. Try it = you'll love it.............. -- John Plimmer, Montagu, Western Cape Province, South Africa South 33 d 47 m 32 s, East 20 d 07 m 32 s RX Icom IC-756 PRO III with MW mods Drake SW8 & ERGO software Sony 7600D, GE SRIII, Redsun RP2100 BW XCR 30, Sangean 803A. GE circa 50's radiogram Antenna's RF Systems DX 1 Pro, Datong AD-270 Kiwa MW Loop, POARDT Roelof mini-whip http://www.dxing.info/about/dxers/plimmer.dx "Guy Atkins" wrote in message . .. Yes, it's very quiet here in the Pacific NW, with the fewest "thunderstorm days" of any place in the continental USA. In mid-winter, with a Western Beverage antenna at dawn, aimed out over the Pacific Ocean, you'd swear your receiver was defective, or the antenna broken. In these conditions, extremely faint tropical band and foreign (TP) mediumwave signals have a fighting chance to be heard (assuming a top-notch, low noise receiver like a AR7030 or my current fave, the SDR-1000. It was under these mid-winter, dawn enhancement conditions that I heard tantalizing faint signals around 3174 kHz (variable) in the late 1990s, which had all the clues of Indonesian "amatir" stations. Think: Indo college kids back home on holiday or weekend breaks, playing non-stop Indo rock music with flea-powered transmitters, no IDs, often distorted audio, no official "RRI" news at the top of the hour, etc. I've heard enough of the real RRI and RPD Indonesian stations to recognize the Indo amatir (pirate) station. Similarly, I've logged very low power Australian x-band stations such as Radio Brisvaani, the Hindi station on 1701 kHz (Brisbane, Queensland). I'd never have a chance to hear this sort of DX, however, at home in the suburban RF jungle near Seattle-Tacoma. These catches were on coastal DXpeditions, under ideal conditions. I do have pretty low noise levels of the RFI, hash-and-buzz sort at home, due to the underground AC mains. The main problem are the dozen or so MW stations registering S-9+40 to S-9+60 dB on the SDR's (calibrated) signal meter. My local 1 kw'er, 1450 KSUH in Puyallup, is a bit over 1 mile from home. When I had a 700 ft. Beverage antenna aimed at my Asian targets, the antenna unfortunately was oriented right at KSUH, too. The signal on 1450 from that antenna registered -13 dBm, which is, I believe, around S-9+65 dB. This is an example of what the trans-Pacific MW stations need to fight through to be heard in a suburban location like this. So far, I'm finding the Wellbrook ALA 100 on a rotator does just fine for snagging the foreign MW DX that makes it through the RF jungle; a Beverage is no advantage. 73, Guy Atkins Puyallup, WA www.sdr-1000.blogspot.com |
Wellbrook ALA1530+ Vs. ALA100?
Ron Hardin wrote: My 6 DA100E whips and 2 ALA1530s are disguised as bird feeders and bird houses, not because of any restriction but because it makes it neighbor-friendly. loop in foreground and whip in background http://home.att.net/~rhhardin/antenna.jpg Both are supported by 8' ground rods tapped in a few feet; the ALA1530 is on a galvinized pipe slipped over the ground rod, with a floor flange screwed on the bottom so it doesn't sink into the ground, making it rotatable by hand. The coax comes off the outside of the pipe and makes a few turns looped around the pipe for slack, this loop being covered by a stove burner reflector against lawnmower attacks. The bird feeder is supported by the antenna rather than vice versa, incidentally. -- Ron Hardin On the internet, nobody knows you're a jerk. Any chance of you posting medium and tight close ups of the DA100Es? A friend in Flagstaff is dealing with (fighting) overly restrictive condo rules and I sent him the photo of the Wellbrook. He may be able to sneak, as in be granted persmission, a vertical active antenna into his backyard. He was allowed to errect a Rat Sahck Diskcone but that makes a very poor HF antenna. Thank you Terry |
Wellbrook ALA1530+ Vs. ALA100?
John Plimmer wrote: It's just bliss to have that phenomena that Guy describes: when the noise on the antenna's is so low you start checking to see if in fact they are connected. It is such a joy to hear stations thousand's of miles away waft in over the airwaves as clear as a bell, yet the signal strength is so low it doesn't even move your "S" meter. What a thrill! It's a pity these sorts of locations are so few and far between. In most locations, atmospheric noise is significant *all by itself*. |
Wellbrook Shielded?
I think it was Seein-I-Dawg who commented about the Wellbrook ALA-1530
being shielded.... As far as I can tell, having looked at their site several times, Wellbrook makes no such claims and points to the loop configuration as the reason why it rejects some near field RFI. This is also born out by the fact that they also sell an Indoor version of the antenna which is packaged in a sort of plastic hula hoop, rather than in Aluminum tubing. Wellbrook does make a very nice preamp and I suspect that the ALA-100 WILL outperform the ALA-1530 and the ALA-330s with 50 feet of wire on it. (I currently have an ALA-1530 and hope to have an ALA-100 shortly so I'll let you know.) Rob Steve wrote: John Plimmer wrote: It's just bliss to have that phenomena that Guy describes: when the noise on the antenna's is so low you start checking to see if in fact they are connected. It is such a joy to hear stations thousand's of miles away waft in over the airwaves as clear as a bell, yet the signal strength is so low it doesn't even move your "S" meter. What a thrill! It's a pity these sorts of locations are so few and far between. In most locations, atmospheric noise is significant *all by itself*. |
Wellbrook Shielded?
Rob wrote: I think it was Seein-I-Dawg who commented about the Wellbrook ALA-1530 being shielded.... As far as I can tell, having looked at their site several times, Wellbrook makes no such claims and points to the loop configuration as the reason why it rejects some near field RFI. This is also born out by the fact that they also sell an Indoor version of the antenna which is packaged in a sort of plastic hula hoop, rather than in Aluminum tubing. Wellbrook does make a very nice preamp and I suspect that the ALA-100 WILL outperform the ALA-1530 and the ALA-330s with 50 feet of wire on it. (I currently have an ALA-1530 and hope to have an ALA-100 shortly so I'll let you know.) Rob Steve wrote: John Plimmer wrote: It's just bliss to have that phenomena that Guy describes: when the noise on the antenna's is so low you start checking to see if in fact they are connected. It is such a joy to hear stations thousand's of miles away waft in over the airwaves as clear as a bell, yet the signal strength is so low it doesn't even move your "S" meter. What a thrill! It's a pity these sorts of locations are so few and far between. In most locations, atmospheric noise is significant *all by itself*. The Wellbrook loops are not shielded. The exposed metal is the loop. The 1530+ high bandwidth version looks ineresting. You could justify the cost if you use it for FM broadcast. Otherwise, get the ALA 100 and roll your own loop. |
Wellbrook Shielded?
Well, judging from my ALA1530, which I have partially disassembled,
there is wire running inside the Aluminum so the aluminum is not the loop. The indoor version doesn't have any aluminum on it either as far as I can tell, just a plastic outer covering. Rob wrote: The Wellbrook loops are not shielded. The exposed metal is the loop. The 1530+ high bandwidth version looks ineresting. You could justify the cost if you use it for FM broadcast. Otherwise, get the ALA 100 and roll your own loop. |
Wellbrook Shielded?
In article . com,
"Rob" wrote: Steve wrote: John Plimmer wrote: It's just bliss to have that phenomena that Guy describes: when the noise on the antenna's is so low you start checking to see if in fact they are connected. It is such a joy to hear stations thousand's of miles away waft in over the airwaves as clear as a bell, yet the signal strength is so low it doesn't even move your "S" meter. What a thrill! It's a pity these sorts of locations are so few and far between. In most locations, atmospheric noise is significant *all by itself*. I think it was Seein-I-Dawg who commented about the Wellbrook ALA-1530 being shielded.... That was a mistake. That Troll usually posts off topic political crap. As far as I can tell, having looked at their site several times, Wellbrook makes no such claims and points to the loop configuration as the reason why it rejects some near field RFI. The loop configuration is a reason that the antenna design will be helpful in reducing local interference. This is also born out by the fact that they also sell an Indoor version of the antenna which is packaged in a sort of plastic hula hoop, rather than in Aluminum tubing. You and I both do not know what is inside the plastic tubing. It might be shielded or it may not. Wellbrook does make a very nice preamp and I suspect that the ALA-100 WILL outperform the ALA-1530 and the ALA-330s with 50 feet of wire on it. (I currently have an ALA-1530 and hope to have an ALA-100 shortly so I'll let you know.) Externally the antenna design is good way to go but it would depend on how it was executed. -- Telamon Ventura, California |
Wellbrook Shielded?
"Telamon" wrote As far as I can tell, having looked at their site several times, Wellbrook makes no such claims and points to the loop configuration as the reason why it rejects some near field RFI. The loop configuration is a reason that the antenna design will be helpful in reducing local interference. Why don't you explain the theory, Mr. Einstein. |
Wellbrook Shielded? Nope!
Actually,
I do know what is inside the plastic loop. If you search on Wellbrook and look at some of the past topics about it, there is one where someone was asking the shortwave shop (their distributor) about the indoor plastic loop, and the guy from the shortwave shop replied that it was flexible and just had wire inside of it, so it could be squished through narrow openings to the attic, I assume. Rob Telamon wrote: In article . com, "Rob" wrote: Steve wrote: John Plimmer wrote: It's just bliss to have that phenomena that Guy describes: when the noise on the antenna's is so low you start checking to see if in fact they are connected. It is such a joy to hear stations thousand's of miles away waft in over the airwaves as clear as a bell, yet the signal strength is so low it doesn't even move your "S" meter. What a thrill! It's a pity these sorts of locations are so few and far between. In most locations, atmospheric noise is significant *all by itself*. I think it was Seein-I-Dawg who commented about the Wellbrook ALA-1530 being shielded.... That was a mistake. That Troll usually posts off topic political crap. As far as I can tell, having looked at their site several times, Wellbrook makes no such claims and points to the loop configuration as the reason why it rejects some near field RFI. The loop configuration is a reason that the antenna design will be helpful in reducing local interference. This is also born out by the fact that they also sell an Indoor version of the antenna which is packaged in a sort of plastic hula hoop, rather than in Aluminum tubing. You and I both do not know what is inside the plastic tubing. It might be shielded or it may not. Wellbrook does make a very nice preamp and I suspect that the ALA-100 WILL outperform the ALA-1530 and the ALA-330s with 50 feet of wire on it. (I currently have an ALA-1530 and hope to have an ALA-100 shortly so I'll let you know.) Externally the antenna design is good way to go but it would depend on how it was executed. -- Telamon Ventura, California |
Wellbrook Shielded? Nope!
Rob wrote: Actually, I do know what is inside the plastic loop. If you search on Wellbrook and look at some of the past topics about it, there is one where someone was asking the shortwave shop (their distributor) about the indoor plastic loop, and the guy from the shortwave shop replied that it was flexible and just had wire inside of it, so it could be squished through narrow openings to the attic, I assume. Rob This question keeps popping up on this newsgroup. Wellbrooks are not shielded. I still like the ALA100 because you can roll your own antenna. Telamon wrote: In article . com, "Rob" wrote: Steve wrote: John Plimmer wrote: It's just bliss to have that phenomena that Guy describes: when the noise on the antenna's is so low you start checking to see if in fact they are connected. It is such a joy to hear stations thousand's of miles away waft in over the airwaves as clear as a bell, yet the signal strength is so low it doesn't even move your "S" meter. What a thrill! It's a pity these sorts of locations are so few and far between. In most locations, atmospheric noise is significant *all by itself*. I think it was Seein-I-Dawg who commented about the Wellbrook ALA-1530 being shielded.... That was a mistake. That Troll usually posts off topic political crap. As far as I can tell, having looked at their site several times, Wellbrook makes no such claims and points to the loop configuration as the reason why it rejects some near field RFI. The loop configuration is a reason that the antenna design will be helpful in reducing local interference. This is also born out by the fact that they also sell an Indoor version of the antenna which is packaged in a sort of plastic hula hoop, rather than in Aluminum tubing. You and I both do not know what is inside the plastic tubing. It might be shielded or it may not. Wellbrook does make a very nice preamp and I suspect that the ALA-100 WILL outperform the ALA-1530 and the ALA-330s with 50 feet of wire on it. (I currently have an ALA-1530 and hope to have an ALA-100 shortly so I'll let you know.) Externally the antenna design is good way to go but it would depend on how it was executed. -- Telamon Ventura, California |
Wellbrook Shielded? Nope!
wrote This question keeps popping up on this newsgroup. Wellbrooks are not shielded. Invisable aluminum. |
Wellbrook Shielded? Nope!
Hi Miso,
I was just making a point for Tekamon. I really like them and know they are not shielded. I'm hoping to get an ALA-100 for Christmas so I can experiment with larger loops. It's obvious that Andy has a good quiet preamp design and this,coupled with a carefully designed balanced antenna, constitutes the 'magic' inside a Wellbrook. Rob wrote: Rob wrote: Actually, I do know what is inside the plastic loop. If you search on Wellbrook and look at some of the past topics about it, there is one where someone was asking the shortwave shop (their distributor) about the indoor plastic loop, and the guy from the shortwave shop replied that it was flexible and just had wire inside of it, so it could be squished through narrow openings to the attic, I assume. Rob This question keeps popping up on this newsgroup. Wellbrooks are not shielded. I still like the ALA100 because you can roll your own antenna. Telamon wrote: In article . com, "Rob" wrote: Steve wrote: John Plimmer wrote: It's just bliss to have that phenomena that Guy describes: when the noise on the antenna's is so low you start checking to see if in fact they are connected. It is such a joy to hear stations thousand's of miles away waft in over the airwaves as clear as a bell, yet the signal strength is so low it doesn't even move your "S" meter. What a thrill! It's a pity these sorts of locations are so few and far between. In most locations, atmospheric noise is significant *all by itself*. I think it was Seein-I-Dawg who commented about the Wellbrook ALA-1530 being shielded.... That was a mistake. That Troll usually posts off topic political crap. As far as I can tell, having looked at their site several times, Wellbrook makes no such claims and points to the loop configuration as the reason why it rejects some near field RFI. The loop configuration is a reason that the antenna design will be helpful in reducing local interference. This is also born out by the fact that they also sell an Indoor version of the antenna which is packaged in a sort of plastic hula hoop, rather than in Aluminum tubing. You and I both do not know what is inside the plastic tubing. It might be shielded or it may not. Wellbrook does make a very nice preamp and I suspect that the ALA-100 WILL outperform the ALA-1530 and the ALA-330s with 50 feet of wire on it. (I currently have an ALA-1530 and hope to have an ALA-100 shortly so I'll let you know.) Externally the antenna design is good way to go but it would depend on how it was executed. -- Telamon Ventura, California |
Wellbrook Shielded? Nope!
Rob wrote: Hi Miso, I was just making a point for Tekamon. I really like them and know they are not shielded. I'm hoping to get an ALA-100 for Christmas so I can experiment with larger loops. It's obvious that Andy has a good quiet preamp design and this,coupled with a carefully designed balanced antenna, constitutes the 'magic' inside a Wellbrook. Rob I'm not sure if it is just an amp, or a wideband transformer plus an amp. wrote: Rob wrote: Actually, I do know what is inside the plastic loop. If you search on Wellbrook and look at some of the past topics about it, there is one where someone was asking the shortwave shop (their distributor) about the indoor plastic loop, and the guy from the shortwave shop replied that it was flexible and just had wire inside of it, so it could be squished through narrow openings to the attic, I assume. Rob This question keeps popping up on this newsgroup. Wellbrooks are not shielded. I still like the ALA100 because you can roll your own antenna. Telamon wrote: In article . com, "Rob" wrote: Steve wrote: John Plimmer wrote: It's just bliss to have that phenomena that Guy describes: when the noise on the antenna's is so low you start checking to see if in fact they are connected. It is such a joy to hear stations thousand's of miles away waft in over the airwaves as clear as a bell, yet the signal strength is so low it doesn't even move your "S" meter. What a thrill! It's a pity these sorts of locations are so few and far between. In most locations, atmospheric noise is significant *all by itself*. I think it was Seein-I-Dawg who commented about the Wellbrook ALA-1530 being shielded.... That was a mistake. That Troll usually posts off topic political crap. As far as I can tell, having looked at their site several times, Wellbrook makes no such claims and points to the loop configuration as the reason why it rejects some near field RFI. The loop configuration is a reason that the antenna design will be helpful in reducing local interference. This is also born out by the fact that they also sell an Indoor version of the antenna which is packaged in a sort of plastic hula hoop, rather than in Aluminum tubing. You and I both do not know what is inside the plastic tubing. It might be shielded or it may not. Wellbrook does make a very nice preamp and I suspect that the ALA-100 WILL outperform the ALA-1530 and the ALA-330s with 50 feet of wire on it. (I currently have an ALA-1530 and hope to have an ALA-100 shortly so I'll let you know.) Externally the antenna design is good way to go but it would depend on how it was executed. -- Telamon Ventura, California |
Wellbrook Shielded? Nope!
Oh, I'm sure there are transformers. Many of the best preamps include
them and there may be input and output transformers for impedance matching and isolation as well. Rob wrote: Rob wrote: Hi Miso, I was just making a point for Tekamon. I really like them and know they are not shielded. I'm hoping to get an ALA-100 for Christmas so I can experiment with larger loops. It's obvious that Andy has a good quiet preamp design and this,coupled with a carefully designed balanced antenna, constitutes the 'magic' inside a Wellbrook. Rob I'm not sure if it is just an amp, or a wideband transformer plus an amp. wrote: Rob wrote: Actually, I do know what is inside the plastic loop. If you search on Wellbrook and look at some of the past topics about it, there is one where someone was asking the shortwave shop (their distributor) about the indoor plastic loop, and the guy from the shortwave shop replied that it was flexible and just had wire inside of it, so it could be squished through narrow openings to the attic, I assume. Rob This question keeps popping up on this newsgroup. Wellbrooks are not shielded. I still like the ALA100 because you can roll your own antenna. Telamon wrote: In article . com, "Rob" wrote: Steve wrote: John Plimmer wrote: It's just bliss to have that phenomena that Guy describes: when the noise on the antenna's is so low you start checking to see if in fact they are connected. It is such a joy to hear stations thousand's of miles away waft in over the airwaves as clear as a bell, yet the signal strength is so low it doesn't even move your "S" meter. What a thrill! It's a pity these sorts of locations are so few and far between. In most locations, atmospheric noise is significant *all by itself*. I think it was Seein-I-Dawg who commented about the Wellbrook ALA-1530 being shielded.... That was a mistake. That Troll usually posts off topic political crap. As far as I can tell, having looked at their site several times, Wellbrook makes no such claims and points to the loop configuration as the reason why it rejects some near field RFI. The loop configuration is a reason that the antenna design will be helpful in reducing local interference. This is also born out by the fact that they also sell an Indoor version of the antenna which is packaged in a sort of plastic hula hoop, rather than in Aluminum tubing. You and I both do not know what is inside the plastic tubing. It might be shielded or it may not. Wellbrook does make a very nice preamp and I suspect that the ALA-100 WILL outperform the ALA-1530 and the ALA-330s with 50 feet of wire on it. (I currently have an ALA-1530 and hope to have an ALA-100 shortly so I'll let you know.) Externally the antenna design is good way to go but it would depend on how it was executed. -- Telamon Ventura, California |
| All times are GMT +1. The time now is 07:20 PM. |
Powered by vBulletin® Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
RadioBanter.com