Keyboard Shortcuts
ctrl + shift + ? :
Show all keyboard shortcuts
ctrl + g :
Navigate to a group
ctrl + shift + f :
Find
ctrl + / :
Quick actions
esc to dismiss
Likes
- Loopantennas
- Messages
Search
|
Locked
RF Systems DX-One Pro MkII - Bi-Loop or not ?
Fraser
Hi All,
A new question to ponder for the Group. I own an RF Systems DX-ONE Pro MKII and have tried to establish exactly what it is from the manufacturer.... they are staying silent :-( For those not familiar with the DX-One, it looks like a giant egg beater and if you believe the sales blurb it uses a high performance, very low noise overload resistant amplifier designed for the Dutch Military. Yet another mystery amplifier design !!!! I can vouch for the low noise element of the claim and it does perform very well at my rural UK location with good rejection of the house noise field. What still mystifies me is exactly what it is in terms of antenna type. It looks like the Bellini Tosi crossed loop DF antennas that I used to use on ships so I wondered if it is a crossed Bi-Loop to give omnidirectional covereage ? I suggested this to the manufacturer and received no response. It could be a compound monopole (folded up into the diamond shape) but the antenna is ground independant and requires only a safety ground for it's inbuilt ESD protection. I have gone as far as X-Raying the antenna "guts" but that did not reveal it's secret. there is a complex amplifier and several torroids. One appears to connect to the "loop arms" and another is at the output connector end of the amp. I should be grateful for any comment that this groups members may have on this antenna and it's design principle. Loop or Not Loop antenna, that is the question :-) I will post a picture of the DX-One in the photos area of this group for those who do not know of it. Fraser |
|
Locked
Re: WL1030 amplifier diagram
At 14:03 07/05/12, Digest Number 813 wrote:
Posted by: "Steve Ratzlaff" steveratz@... steveratzClick! (and save web page) The higher-resolution image obtained then zooms quite well in Irfanview - it looks a bit blue-fringed, like a slightly out-of-focus scan of a ballpoint pen original, but quite readable. Regards, LenW -- Content of a follow-up post should exceed quoted content. (rfc1855) |
|
Locked
Re: Wellbrook ALA1530
At 14:03 07/05/12, Digest Number 813 wrote:
Posted by: "n2chi" davidgriffin@... n2chiAllegation of involvement in a conspiracy is not what I would call "civil" - more like "civil-actionable". How fortunate for Mr Ikin that he put his allegation into a private email and not publicly to the group! (And would most of you learn to trim so that your comment is not dwarfed by your huge quote?) Regards, LenW -- If you are sending a reply to a message... be sure you summarize the original at the top of the message, or include just enough text of the original to give a context. This will make sure readers under- stand when they start to read your response.... Giving context helps everyone. But do not include the entire original! (rfc1855) |
|
Locked
Re: Wellbrook ALA1530
Patrick Reynaert
Fraser <fraser.castle@...> wrote:
Thanks for the information William. Having slept on this matter, and mellowed a little, I have the following personal comments.... Is it time to draw a line under this copyright, IPR & Patent issue ? Sounds like a good idea Fraser. I just wanted to point out that just publishing the schematic is not as easy as it seems. Let's get back to the fun stuff. Patrick. --------------------------------- Luggage? GPS? Comic books? Check out fitting gifts for grads at Yahoo! Search. |
|
Locked
Re: Wellbrook ALA1530
hpmwphaser
<note from Moderator: Please, everyone remember to trim>
--- In loopantennas@..., "gfreport1" <gfreport@...> wrote: ...big snippage... <Moderator...> For whatever it is worth repeated testing showed that active dipolesto build a loop, one could do much worse to build a WL1030. Plans canbe found at wl1030.com. The active dipole(s) referred to here can be found in the article "Some of my favorite small antennas..." in The Dallas Files at www.kongsfjord But I would recommend noise reducing verticals (phased, if possible) rather than dipoles or loops. Dallas Lankford |
|
Locked
Re: Wellbrook ALA1530
Laurence Taylor
Having just joined the new Loopantennas list. I see that youand some other members are conspiring to breach Wellbrook Communications Copyright of one of its loop antenna designs. I must remind you that Wellbrook Communications owns the design Copyright and all Intellectual Property Rights for its products. Well, I know whose loop I won't be buying then, if that's the way he joins a thread! What an attitude to take to people who might otherwise be supportive of his product. It's of no consequence; there's plenty of other designs, and I doubt if his effort is significantly different; there's only a certain number of ways you can make something! rgds LAurence ... "Yield to temptation, it may not pass your way again." - L. Long ~~~ Tag-O-Matic V.13F |
|
Locked
Re: Wellbrook ALA1530
Fraser
Thanks for the information William.
Having slept on this matter, and mellowed a little, I have the following personal comments.... Is it time to draw a line under this copyright, IPR & Patent issue ? It was not my intention to cause upset when I asked why Patrick was so quiet. I do not consider myself a Group "Troll". I can understand that Andy is concerned about damage to his business and I also believe that there were better ways to tell Patrick of his concern. The copyright/IPR issue has just muddied the waters somewhat. It is not my intention, nor has it ever been, to do damage to Andy's income or Wellbrook as a company. Andy has done a great service to the hobby over the years and if my previous responses seemed ungrateful I apologise. Now back to the real question.... If you wanted to build a wide band untuned active loop, how would YOU do it ? The common base amplifier design seems to be a good contender at the momemt and we have now got the AA7U design to consider as well as the WL1030. The group contains some very clever people so it is not unlikely that one of those people could come up with a design suggestion that is as good as, or better than the ALA1530. As an interesting side note. I recently reverse engineered a professional (=$$$$) 17 inch untuned broadband active loop and was surprised at the design. The "front end" was a CZ8320 amplifier IC. This fed four stages of bipolar transistor amplification (2N3570 & 2N2222) in order to produce the required gain. The design was unbalanced and the loop consisted of 2 turns of RG8 coax core 9 inc polythene insulation) in an aluminium screen. Another interesting design element was the coupling and decoupling capacitors.... 2.2uF, 680nF and 10nF were wired in parallel and used as interstage coupling capacitors. A similar arrangement was used for the decoupling of stages to 0v. I presume the three parallel capacitors improved broadband frequency response. Regreatably I am not able to post the schematic of this particular loop on the group as I would DEFINITELY end up in trouble ! (US lawyers scare me !) Regards to all Fraser performed====================R2000swler mentioned this thread to me. the used Wellbrook ALA 1530 that he aquired in a trade. It is alwaysto build a loop, one could do much worse to build a WL1030. Plans canbe found at wl1030.com. |
|
Locked
AA7U Loop Preamp photo added to Photos sections
Steve Ratzlaff
I've just put my own Loop Preamp that I designed in 2006 in the Group's Photos section. It's a balanced preamp and is neither a Norton circuit nor a common-base circuit. I adapted it from an Ulrich Rohde DJ2LR circuit. It's broadband, and I've used it with a 30m circumference loop, though I don't have any nearby strong transmitters in the north/south direction the loop was oriented. It would need a smaller loop if you had strong stations nearby. I've never actually tried it with a much smaller loop like 1m diameter, but it works well with larger loops.
I can also email you the 40kb diagram if you can't read it in the Photo section--but please try there first. (I only have a slow diallup.) If you try it, or improve its performance, please let me and the Group know the details. Thanks, Steve AA7U |
|
Locked
Re: Wellbrook ALA1530
Paul E. Cater
Good day all,
toggle quoted message
Show quoted text
I think the concept of the copyright and a patent are getting equal billing or confused here. A copyright is a form of protection for original works of authorship fixed in a tangible medium of expression. These include literary, dramatic, musical, and artistic works like, poetry, novels, movies, songs, software, et. It does not cover facts, ideas, systems, methods of operation, but may protect how they are expressed. A patent protects inventions or discoveries. These are not protected by copyright. is a good place to start reading. The interesting question is if someone or a group of someone's can "conspire to breach a copyright" of something when the point seems to be over a design and not an original work of authorship? In other words, the paperwork may be protected but the design requires a patent. Regards, Paul n2chi wrote:
|
|
Locked
Re: Wellbrook ALA1530
n2chi
Andy's note seems appropriate to me. (It's called due dilgence.) Of
toggle quoted message
Show quoted text
course he is concerned...he designed the circuit and makes a living selling them. Whether one believes his work is copyright-able or patentable is up to the attorneys, I suppose, but you can't blame a guy for trying to protect his work and his note seemed perfectly civil. The ability to protect one's intellectual property through copyright and patents is what encourages entrepreneurs to invent and is the basis of the economic success of the western world. Read some history. Dave --- In loopantennas@..., "Fraser" <fraser.castle@...> wrote:
|
|
Locked
Re: WL1030 amplifier diagram
Steve Ratzlaff
Thanks, it really never occured to me to click on the image (doh), but it indeed comes up large enough to (barely) make out the grainy diagram. (The power supply filter doesn't do as well.) (I was saving the file then trying to enlarge the diagram--didn't work. :) )
toggle quoted message
Show quoted text
I wouldn't think a balanced amp using ICs that draw a nominal 18 mA each could come close to a discrete bipolar version biassed at 40-60mA per device, for IMD performance. Steve ----- Original Message -----
From: "Jay Heyl" <yahoogroups@...> To: <loopantennas@...> Sent: Friday, May 11, 2007 11:05 AM Subject: Re: [loopantennas] WL1030 amplifier diagram Steve, |
|
Locked
Re: Wellbrook ALA1530
On 5/11/07, Vince Werber <ka1iic@...> wrote:
Most everyone on this list can do better by using the simple designs fromI respectfully suggest you should try one of the Wellbrook antennas before expressing an opinion on how some other antenna would stack up against it. -- Jay |
|
Locked
Re: Wellbrook ALA1530
Fraser
Hi All,
I Have read and re read the veiled threat from Andy Ikin and it doesn't sit well with me. This is the first time a group to which I have belonged has been accused of attempting to commit an illegal or in some manner "wrong" act. My reply to that accusation is HOGWASH ! and get some perspective here Mr Ikin. There would appear to be some very knowledgeable people in this Group and it is normal for people to wonder how something works as has already been stated. Most new electronic equipment that I buy has a schematic available that I study for INTEREST ONLY. If no schematic is available, and the circuit not too complex, I reverse engineer the circuit and draw the schematic. A classic example of this is my NASA dual freq NAVTEX antenna and my NASA NAVTEX PC Engine. I now know exactly how they both work and the limitations of their design. NASA used a PIC chip to generate the required Local Oscillator frequencies..... yes they used a microprocessor in an antenna !!! I learnt a great deal from the design and managed to improve it for UK inland use. I am not, however, about to go copying these items for commercial use ! With regard to the Chinese 'threat' of cloning..... Chinese Amateurs appreciated the excellent performance of the AOR LA320 but the price was more than they could afford. An LA320 schematic was produced and released into the Chinese Amateur domain and many home made examples now provide good service to these Amateurs. How many commercial LA320 clones have we seen ? There is ONE chap selling a similar but not cloned LA320 type loop on ebay. It's called the BCL-01 MkII and it's an individual and not a company mass marketed product. The reason.... there isn't enough profit to be made. The Degen loops are the mass market offerings from China .... cheap and cheerful. That's my little rant on this topic off my chest.... a conspirator indeed ! Fraser --- In loopantennas@..., Jim Dunstan <jdunstan@...> wrote: just himself..got this email below (or should I say threat) from Andy Ikin some Copyrightother members are conspiring to breach Wellbrook Communications Wellbrookof one of its loop antenna designs. I must remind you that PropertyCommunications owns the design Copyright and all Intellectual work hasRights for its products. become involved in 'reverse-engineering'. When I was a kid therewere more carcasses of old radio's, clocks, motors, and other various deviceslying around in the workshop in my Grandmother's basement. In addition Ialso found many ways to improve the items I reverse-engineered and oftenmanufacturer's claims. It is a fun exercise and perfectly okay from a legal andethical point of view. Later I have often written manufacturers withsuggested improvements in design and have received several letters ofappreciation. infringement of intellectual property as defined in a patent .... the matter isusually decided by who has the best lawyer. The discussions in this forumnothing to do with infringing someone's intellectual property rights, letalone a conspiracy.manufacturer through contract or employment he would certainly have ethical andperhaps legal constraints. However I have no such relationship to themanufacturer and if I want to voice opinions as to how a product is designed andworks through either using it or 'reverse-engineering' it ..... I amperfectly free to do so.of a product has anything to fear from interested parties on a forumsuch as this .... individuals wanting to build their own, or simply expandtheir knowledge are not a threat. Not much is built in the Westernworld these days anyway .... look to China and India .... not hobbyist hi hi. |
|
Locked
Re: Wellbrook ALA1530
--- In loopantennas@..., "Fraser" <fraser.castle@...> wrote:
.... I can understand Andy Irkins concern however. From what has beensaid, Wellbrook is a very small business and we are on the edge ofrevealing his ALA1530's 'secret'. With the required information, SWL's will beRadio enthusiasts and SWL's do for entertainment and learning ?Ahem. From the US Govt's Patent, Trademark, and Copyright website: "The copyright protects the form of expression rather than the subject matter of the writing. For example, a description of a machine could be copyrighted, but this would only prevent others from copying the description; it would not prevent others from writing a description of their own or from making and using the machine." So a Patent provides protection for the design for a physical machine such as a loop antenna. A copyright (as others have pointed out) only protects the exact appearance of that completed machine, and so prevent a competitor from producing a counterfeit. And it must be substantially unique in appearance to warrant protection by copyright, or only minor changes allow similar looking machines from appearing (as others have also pointed out). Steve Greenfield |
|
Locked
Re: WL1030 amplifier diagram
Steve,
toggle quoted message
Show quoted text
I clicked on the diagram I think you're referring to and it loaded a second, larger version of the schematic. It was plenty large enough to read, assuming I knew how to read it. -- Jay On 5/11/07, Steve Ratzlaff <steveratz@...> wrote:
How does one obtain a larger or higher resolution circuit diagram for the |
|
Locked
Re: WL1030 amplifier diagram
Steve Ratzlaff
How does one obtain a larger or higher resolution circuit diagram for the WL1030 amplifier? The tiny diagram that you can download from the site is too small to make out anything in the picture, and if you try to increase the size, it just gets grainy and then you can't tell anything. In fact, all the pictures and diagrams are too small when you download them.
toggle quoted message
Show quoted text
Steve ----- Original Message -----
From: "C. Beijersbergen" <c.beijersbergen@...> To: <loopantennas@...> Sent: Friday, May 11, 2007 2:45 AM Subject: [loopantennas] active loop design To all interested in a 1 meter diameter active broadband loopantenna, in: |
|
Locked
Re: Wellbrook ALA1530
Jim Dunstan
At 10:37 PM 5/10/2007 -0700, you wrote:
Hi Fraser, Hi Andy, et al Well, I believe anyone who is interested in learning how things work has become involved in 'reverse-engineering'. When I was a kid there were more carcasses of old radio's, clocks, motors, and other various devices lying around in the workshop in my Grandmother's basement. In addition I also found many ways to improve the items I reverse-engineered and often revealed the simplicity, shortcomings and exaggeration of manufacturer's claims. It is a fun exercise and perfectly okay from a legal and ethical point of view. Later I have often written manufacturers with suggested improvements in design and have received several letters of appreciation. If one plans to go commercial with a product then it is a different situation and it is not all together clear what constitutes infringement of intellectual property as defined in a patent .... the matter is usually decided by who has the best lawyer. The discussions in this forum concerning how a particular broadband loop works certainly has nothing to do with infringing someone's intellectual property rights, let alone a conspiracy. If one of the persons discussing the 'design' or 'formulation' of a particular product has had a direct relationship with the manufacturer through contract or employment he would certainly have ethical and perhaps legal constraints. However I have no such relationship to the manufacturer and if I want to voice opinions as to how a product is designed and works through either using it or 'reverse-engineering' it ..... I am perfectly free to do so. After having said all this ... I don't think that the manufacturer of a product has anything to fear from interested parties on a forum such as this .... individuals wanting to build their own, or simply expand their knowledge are not a threat. Not much is built in the Western world these days anyway .... look to China and India .... not hobbyist hi hi. Jim |
|
Locked
Re: Wellbrook ALA1530
thanks for letting us know Partrick
agree with your concerns likely the low non-inductive resistance across the loop to obtain the wide bandwidth is what some of us were missing so as to give reason for its superior performance besides of course of the low noise vhf bipolar transistors best wishes Paul V Birke PEng Guelph ON Canada |
Steven Greenfield AE7HD
to navigate to use esc to dismiss