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#71
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Telamon wrote:
In article , Dave wrote: RHF wrote: Dave, IIRC a good Amateur Radio 1/4 WL Vertical-Up-Leg by 1/4 WL Horizontal-Out-Arm {Inverted "L" Antenna requires very little Tuning and performs very well near and far on the HF Band that it is 'cut' to use on. Using a direct-connect or 1:1 UnUn at the Feed-Point * Half-Wave Inverted "L" Antenna : 1/4 WL + 1/4 WL Where-as the more common Shortwave Listener (SWL) type of {Random Wire} Inverted "L" Antenna is un-equal and usually has a shorter Vertical-Up-Leg and a longer Horizontal-Out-Arm of at least 1V-to-2H and often 1V-to-3H or more. Using a 9:1 Matching Transformer and Ground Rod at the Feed-Point which is at the base of the Vertical-Up-Leg. "Random" implies otherwise. Instead of a 9:1 UnUn, imagine one of these at the feed point: http://www.mfjenterprises.com/Produc...ductid=MFJ-927 I enjoy playing with these kind of things. So I got a license to transmit. Some call that "elitist", I call it self-indulgent. Remote tuners are the right way to do things. Much better than a tuner in the shack. A tuner in the shack matches the radio to the transmission line. There is still a mismatch at the feedpoint. |
#72
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John Smith wrote:
Dave wrote: ... "Pray tell"? Alas and alack. Zounds! Unfortunately, your editing is a bit severe and I have no idea what you're talking about. Well, if you can't remember your own text, nor your "side" of an argument, between posts--I think it is all for moot ... Regards, JS Like you're the only person I talk with... |
#73
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John Smith wrote:
I said NO such thing, indeed, I stated the EXACT opposite, it allows maximum power transfer to the antenna, however, the losses in the POOR antenna are now increased due to the losses in the matchbox--as heat. And, no problems which exist in the POOR antenna have been rectified, they are just masked ... That is vastly oversimplified. |
#74
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![]() "KC8QJP" wrote in message . .. "Richard Clark" wrote in message ... On Tue, 23 Dec 2008 09:46:07 -0800 (PST), PJ wrote: Folks, I have purchased a Sangean ATS-909 World Receiver. It is equipped with an internal ferrite antenna för MW and LW, and a telescope antenna for SW and FM. It also comes with a portable SW antenna (ANT-60), seven meters long. Is this external antenna generally sufficient for SW reception, or should I get a different antenna? If yes, is there a solution that doesn't cost all that much money? I have a copy of the 2009 World Radio TV Handbook, and they are talking about a Wellbrook ALA-1530+ loop antenna, and let me tell you, that one is well past my budget, because it costs $466... I am looking for something a lot cheaper... :-) If it is recommended to replace the ANT-60, that is. PJ Hi PJ, With your location in Sweden, a long wire should pick up a lot of stations unless you are buried deep in a valley. That long wire can be as simple as 10 meters of wire with a clip to attach it to the whip of the Sangean. When I was in Africa last year, that was enough to fill my cheap SW set with signals from everywhere in Africa up into Europe. Toss the wire out a window up into a tree. It is at least a cheap, first attempt to see if you need anything more than that. 73's Richard Clark, KB7QHC try the superskyhook sloper it works wonders over hear! http://i40.tinypic.com/2ykgg05.jpg mary xmas That looks like junk,KC8QJP . You're better off sticking to the bogus tax returns or are you still in prison for that? FORMAL DISCIPLINARY HEARING-KATHLEEN R. LEE Chairman Woods noted that Kathleen Lee was issued CPA certificate 36,525 on July 15, 1998. The hearing was to consider disciplinary action against Ms. Lee's CPA certificate pursuant to Ohio Revised Code section 4701.16(A)(5), conviction of a felony under the laws of any state or of the United States. Ms. Lee was convicted in the United States District Court, Northern District of Ohio of five counts of Aiding & Assisting in Filing False Tax Returns, a violation of 26 USC 7206(2), on June 12, 2000. Ms. Lee did not appear at the hearing. The Board agreed to deliberate the disciplinary action in a later executive session. Action taken. Kathleen R. Lee, CPA 4701.16(A)(5)-Convicted of aiding & assisting in filing of false tax returns. CPA certificate revoked. |
#75
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On Dec 28, 4:02*am, RHF wrote:
"N" - Alas in my heart I am still "that" 8-Year-Old that gets daily joy from DXing the AM-BCB and the Shortwave Bands; and more importantly simply listening to the radio : One Word "Enjoyment". "N" - You over time have evolved and grow with The Craft -while- I still simply enjoy it's less technical aspects as a user : We are different and therefore naturally see things differently. ~ RHF *. I was pretty primitive in the early days. :/ Not much money, so I made do with some weird stuff. Here is my "radio room" when I was in the 7th, 8th grade or so. Probably about 1971. The "room" is the closet in my bedroom.. http://home.comcast.net/~nm5k/r2.jpg The radio was a philco portable. Covered 4-12 mhz. No BFO.. So... I would use the white AM radio sitting behind it as a BFO. :/ Not the most fun in the world, being neither radio was the most stable things around.. But it would let me listen to CW and SSB with tuning tweaks every once in a while. Well, maybe more than once in a while.. ![]() The other white AM radio to the left was more for the clock, and I used the radio in it for local AM listening most of the time. The antenna was just a random wire strung out the back window. The contraption in the foreground was the first transmitter I built. It was a single 6V6 run off line voltage for the B+. Did maybe 5-10 watts I guess.. 40m, and I had two crystals. Look at my advanced scotch tape coil forming construction. :/ The chassis was WW2 Navy issue.. The circuit from the 1949 ARRL handbook. Yes, it actually worked.. ![]() I later rebuilt it using a transformer, and a bit more power. I used it as my first novice transmitter for a good while. By that time, I had a Hammarlund HQ-110 for a receiver. But as a SWL, I listened to half a zillion stations just with that little philco portable and about 50 feet of wire hooked to it. Spent half a fortune "to me back then" on IRC's to get faster QSL replies. You can see a RAI card on the wall. They sent me magazines for about 20 years after that card.. I still got color RAI magazines into the late 80's at least.. For many years, I used to get a Christmas card from Radio Havana.. Every year.. Then like the RAI mags, they finally quit coming. I used to get some real nice glossy color magazines from China back in those days. :/ The FBI probably thought I was some kind of communist being I used to get so much mail from them... |
#76
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RHF wrote:
... JS - What you call a "simplistic manner" IMHO is a will 'crafted' answer by "RL" designed to answer the readers question in a 'manner' that the reader could easily understand, accept and act-on. communications is about speaking 'to' the reader : not 'at' them - iane ~ RHF . I have no problem with the way Roy presented the material ... and, I believe there is high probability that you are correct, some people are more concerned with how material is delivered rather than the material itself ... I don't do well in those situations. And, I wish to accept no responsibility in having to participate, it makes for too much work. I simply wish to cut to the heart and deliver the material in a manner I prefer, I am sure there some who prefer the importance of material over the presentation ... Regards, JS |
#77
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Dave wrote:
John Smith wrote: I said NO such thing, indeed, I stated the EXACT opposite, it allows maximum power transfer to the antenna, however, the losses in the POOR antenna are now increased due to the losses in the matchbox--as heat. And, no problems which exist in the POOR antenna have been rectified, they are just masked ... That is vastly oversimplified. Absolutely, and at some point I must trust the reader has the resources to extrapolate; otherwise, all postings would soon turn in to the length, depth and completeness of a college textbook ... For example, an antenna is a two lane road, running in both directions(T/R), the same parameters which allow it to be the best choice for transmitting, also are in action when that same antenna "plucks" its' signals from the ether ... something I have pointed out in multiple ways, multiple times ... The average person must hear, read, study the same material six times before "learning" it. And, an instructor once pointed out to me, not all people respond to the same method, personality, mode-of-presentation as another or others ... so, he pointed out the importance of gathering data from multiple sources until the "epiphany" is realized ... Regards, JS |
#78
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RHF wrote:
On Dec 27, 7:46 pm, John Smith wrote: wrote: Well, sure, but what does transmitting have to do with anything? We are not talking about transmitting. ... It has EVERYTHING to do with it, it is the same communication, both ways, simply in reverse ... like I have stated before, the exact same laws of physics governing the antenna makes it equally acceptable to both transmitting and receiving. The same pattern seen in the signal transmitted will be seen in the signal(s) received. - Your argument is the equivalent to arguing that - a car designed to go forward would not be - acceptable when backing up ... - simply ridiculous! - - Regards, - JS JS -think-about-it- IF 'by-design' the Car is in-fact designed to go "Only" Forward : * It may 'only' have Forward Gears and a Transmission that has NO Reverse. * No Rear Window * No Rear Mirror NOT So Ridiculous ~ RHF http://www.prweb.com/prfiles/2006/10...onmeteor72.jpg . Just an Example of "Single Focus" Thinking : Optimizing Your Results For One Purpose. Sort of what Shortwave Radio Listeners (SWL) do when they consider how they are going to Design, Build and Use an Antenna for the Hobby of Shortwave Radio Listening (SWLing) Yes as you have pointed out : There is a Greater Boby of Knowledge and Practicum Out There That Could Be Considered and Used -but- The Shortwave Listener (SWL) often is 'selective' in what they consider and use to achieve their specific limited goals. It Has To Do With "Level-of-Involvement" : * Many/Most Amateur Radio Operators {Hams} have the well earn knowledge and experience to function 'like' an Auto Mechanic -wrt- Cars * * Hams at their best are Advocates of the Technology [ Practicers of The Craft ] * Many/Most Shortwave Radio Listeners (SWLs) simply enjoy a level of knowledge and experience to function 'like' a Car Driver -wrt- Cars * * SWLs at their best are Hobbyists Enjoyers of the Technology [ Users of the Technology ] TBL : Both are Need -and- Both are Different ~ RHF . I see you are ready to go to extraordinary lengths to justify your statements or propose "special cases" which are only correct in extreme circumstances of very limited parameters--this is all fine, however, carry on without me ... Again, it is as true as when I originally stated it, the same antenna, its efficiency, fitness-for-purpose, pattern delivered, etc. will work the same, both forward (transmitting), or in reverse (receiving.) I am sure there exists the possiblily of "breaking" or "orchastrating" the antenna physics to bring about a special case or cases ... no practical use I have yet seen has required this. Many hams wish to think themselves "special" because of their hobby, now you have brought me to the realization that there is the equivalent in the SWL'ers hobby ... to me, it just looks like one of my other hobbies, like tropical fish, for example. Regards, JS |
#80
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Dave wrote:
... I have taken ordinary lamp zip cord, split the two leads apart to for a 1/4 wave dipole and fed the end of the remaining length of zip cord with a balun to the rig (some zip cord is ~68-72 ohm balanced line, the mismatch is more than acceptable for field/emergency use.) Never, say never ... some ham will do it! Regards, JS Yes,some ham will do it, with a 3 Watt transmitter tucked into a Sucrets tin, and work 50 countries with his zip cord dipole. Now, I'd say, "That's the spirit!" Warm regards, JS |
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