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#1
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Can anyone tell me about them?? Are they any better or worse than wire
antenna?? Thanks for any comments about this Steve |
#2
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Stephen Drummonds wrote:
Can anyone tell me about them?? Are they any better or worse than wire antenna?? Thanks for any comments about this Steve An active antenna can be a wonder. Compact size. Excellent gain. Offers a lot of mounting choices. Uniform impedance across the spectra. An active antenna can also be a PITA. Subject to overload. Increased noise floor. Fragile connections. Susceptible to damage by static. Two things will determine whether an active antenna will be right for you: 1) the quality of the active antenna. 2) the RF levels in your listening area. If you're not in a high RF zone...that is to say, if you don't have local MW transmitters...you can get away with a relatively inexpensive active while still enjoying decent performance. A poorly designed active in a high RF area, will overload. Producing cross modulation artifacts, and some stations will appear multiple locations up and down the dial. You may also experience hum when a strong clear signal is zeroed in. A nearby lightning strike can wipe out an active in a stroke. A random wire is not subject to overload. Although the front end of your receiver may be. A random wire can be cut to size and conditions. And will often have a lower noise floor at the input to your receiver than an active. If you do overload your receiver, you can always reduce the length of the wire. A good active can cost you between $400 and $600 without cracking a sweat. A good active will often require careful placement to avoid man made noises. But this can be true of any antenna. Are they better or worse? Neither. Each has its applications. Each is superiour under specific conditions. You have to determine if an active is right for you based on your own unique circumstances, expectations. My personal recommendation...start with a random wire, and see how it works. Then experiment to determine if modifying your random wire will get you where you want to go. Along the way, if an active is a better choice, you'll see the clues. I have one active which I take on the road with me. At the home base, I use only passives. |
#3
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In article ,
"Stephen Drummonds" wrote: Can anyone tell me about them?? Are they any better or worse than wire antenna?? Thanks for any comments about this Steve That's a big topic. It depends on many factors like what kind of active antenna you are looking at and comparing it to what kind of passive antenna. A big factor is where you live. If you live in town with a lot of local noise on a small lot an active antenna could be a good choice. If you are far apart from your neighbors and have a good size lot a passive wire antenna is probably a better choice. You are going to have to give us more information. -- Telamon Ventura, California |
#4
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Stephen Drummonds wrote:
Can anyone tell me about them?? Are they any better or worse than wire antenna?? Thanks for any comments about this Steve They can work better, depending on individual situations. |
#5
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On Aug 18, 3:34*am, "Stephen Drummonds"
wrote: Can anyone tell me about them?? *Are they any better or worse than wire antenna?? * Thanks for any comments about this * * * * * * *Steve D Peter Maus and Telamon gave you good advice. Always try a passive wire antenna first if you have enough yard space. See my thoughts on that and my own experiments over the years at: http://www.dxing.info/community/view... 95db5c0f1183 If you can't get up a passive antenna then there is quite a wide choice of active powered antenna's. The best reviews in one place of all those can be found in Passport to World Band Radio: see http://www.passband.com/ It's well worth buying because it has good advice and good reviews of all sorts of radio gear. However, I don't always agree with them as I have owned some of things that they rate quite highly and found them absolute junk (mainly anything MFJ [Mighty Fine Junk]). With active antenna's the general rule applies - the more you pay the better it will be. The cheaper ones tend to pick up a lot of static and suburban noise and can be subject to overloading if you have powerful stations nearby. Also some of them are not very good on the AM MW bands and may not work on the LF/LW band at all. The two best actives in my opinion are the Wellbrook Ala1530 and the RF Systems DX1 Professional MkII. See: http://www.wellbrook.uk.com/products.html#ALA1530 http://www.rf-systems.nl/DX-one.html I have owned a DX1 Pro for eight years now and it gives me superb reception. Here are my various thoughts on this great antenna: http://www.dxing.info/equipment/dx1pro.dx http://www.dxing.info/community/view...hp?f=17&t=2343 http://www.dxing.info/community/view...hp?f=17&t=2353 Please remember though that active antenna's must have the same care and attention to their placing as a good passive wire antenna. The higher up they are the better, erect it away from household noise sources and ground it to earth well. Universal also have a good range of antenna's. See: http://www.universal-radio.com/catalog/sw_ant.html Have fun and good luck. John Plimmer, Montagu, Western Cape Province, South Africa South 33 d 47 m 32 s, East 20 d 07 m 32 s Icom IC-7700, Icom IC-756 PRO III with MW mods ERGO software Drake SW8. Sangean 803A Sony 7600D, GE SRIII, Redsun RP2100 Antenna's RF Systems DX 1 Pro Mk II, Datong AD-270 Kiwa MW Loop. http://www.dxing.info/about/dxers/plimmer.dx |
#6
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On Sun, 17 Aug 2008 20:34:31 -0500, "Stephen Drummonds"
wrote: Can anyone tell me about them?? Are they any better or worse than wire antenna?? Thanks for any comments about this Steve I have a Dymek DA100D active antenna I've used for years, indoors, on an NRD-525 receiver. It pulls in stations, but not as well as a full size outdoor wire antenna -- the Dymek is about 2 S-units down on a given frequency, compared to an Alpha Delta 1/4 wave swl sloper. On the other hand, the Dymek is a heck of a lot smaller than a big outdoor wire; it has about a 5-foot whip on it. I do like the Dymek indoors, as it allows safe listening when there are thunderstorms about. But a simple wire, thrown out the window, may receive as well or better, and be a lot cheaper. Also, in reference to another post, I'm about a mile from a 50,000 watt AM station at 550 khz and it does not seem to cause a problem with the Dymek active antenna. bob k5qwg |
#7
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Stephen Drummonds wrote:
Thanks to all who gave me some very good answers I will do some more research thankgs again Steve Don't forget the MFJ-1024. Pretty much the same as the Dymek, except for the flimsy mechanicals on the MFJ. |
#8
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Now, wait a minute! True, if you buy any Mighty Fine Junk, you might
need to tightnen up a few nuts, bolts, or screws.I think they have a few brews while they (Mighty Fine Junk) are working. www.MFJEnterprises.com I have never used an active antenna before (or have I? that Tiny Tenna which was dead on arrival) so I really don't know. cuhulin |
#9
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Martin F. Jue's ancestors were from mainland China.They helped build the
Union Pacific Railroad. Wayyyyyy back in those years while the Railroads were building, some of them had a Railroad Car that had prostitutes in those Cars. cuhulin |
#10
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Dymeks are as rare as hens teeth nowadays, aren't they? I think active
antennas introduce ''noise'' into the signal. Now, the Red Light District got it's name many years ago when some Railroad people would set their red lantern down in front of a window outside of whichever of their galfriends they were visiting.That Railroad lantern meant, Keep Out! www.mfjenterprises.com/about_mfj.php cuhulin |
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