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#21
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To be honest I really don't know what to call it, all I know is I can hear
several voice on some freq's! Sorta like the voices in my head! : } "Telamon" wrote in message ... In article , "Lisa Simpson" wrote: Went to the MFJ website & ordered the 956 preselector. Hope their products are better than their website & ordering process! : } "Telamon" wrote in message ... In article , "Lisa Simpson" wrote: Fishing for recommendations for antenna preselectors that would work well with a Radio Shack DX-394 & Eavesdropper C antenna . . . http://www.universal-radio.com/catalog/preamps/2964.html http://www.universal-radio.com/catalog/preamps/3736.html You might want to look on Ebay. This does not have a power supply and it is not known if it is working so I would stay away from this one. http://cgi.ebay.com/MFJ-Preselector-...emZ5870550105Q QcategoryZ15051QQssPageNameZWDVWQQrdZ1QQcmdZViewIt em Well I hope it does what you want it to do. In another thread you spoke of co-channel interference and a tuner can't help you with that but it will help you if you have an image problem. -- Telamon Ventura, California |
#22
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: }
"Buzzygirl" wrote in message . .. "Lisa Simpson" wrote in message . .. Went to the MFJ website & ordered the 956 preselector. Hope their products are better than their website & ordering process! : } Lisa, Some of their stuff is okay. I've built and enjoyed many of their kits. I've had good luck with their customer service as well; one of the kits I ordered from them was missing a couple of parts. I e-mailed them and they sent the parts out overnight. Jackie |
#23
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I can hear more than one station on some freq's . . .
"John S." wrote in message oups.com... Lisa Simpson wrote: Fishing for recommendations for antenna preselectors that would work well with a Radio Shack DX-394 & Eavesdropper C antenna . . . What is the problem that you want to cure with the preselector. |
#24
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Lisa Simpson wrote:
I can hear more than one station on some freq's . . . "John S." wrote in message oups.com... Lisa Simpson wrote: Fishing for recommendations for antenna preselectors that would work well with a Radio Shack DX-394 & Eavesdropper C antenna . . . Lisa, As you probably know, it's not uncommon for more than one shortwave station (country) to be using the same frequency at the same time. However if one or more of the stations you're hearing is not actually transmitting on that particular frequency, you have either an *image rejection* problem or *intermodulation* (Google those two topics). The first is caused by insufficient selectivity in the receivers' front-end, while the latter results from not enough dynamic range. A passive preselector should help to reduce both of these problems. |
#25
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On Thu, 23 Feb 2006 04:36:29 GMT, HFguy wrote:
Lisa Simpson wrote: I can hear more than one station on some freq's . . . "John S." wrote in message oups.com... Lisa Simpson wrote: Fishing for recommendations for antenna preselectors that would work well with a Radio Shack DX-394 & Eavesdropper C antenna . . . Lisa, As you probably know, it's not uncommon for more than one shortwave station (country) to be using the same frequency at the same time. However if one or more of the stations you're hearing is not actually transmitting on that particular frequency, you have either an *image rejection* problem or *intermodulation* (Google those two topics). The first is caused by insufficient selectivity in the receivers' front-end, while the latter results from not enough dynamic range. A passive preselector should help to reduce both of these problems. Image is caused by multiple IFs being present. It is an inherent design quirk in single conversion receivers. Unless a receiver is a TRF style, it is not expected to have any front-end selectivity beyond broad bandpass filters. |
#26
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Sometimes,I hear two stations on the same frequency.What is needed is a
good null out antenna. cuhulin |
#27
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Sometimes,I hear two stations on the same frequency.What is needed is a
good null out antenna. cuhulin By this I assume you mean a steerable loop; this can be a good solution if both are actually on that frequency. That MFJ Noise Canceller I use, in addition to zapping noise, can also null out offending stations using two phased antennas. It can kill a pretty strong station well enough to reveal a much weaker one underneath. The only drawback to this unit that I can see is that it can only zap one noise source or station at a time. Multiple interference sources would require multiple units in series; and I'm not sure what that would do to the signal either. Others here have tried multiple unit noise canceller arrays with success. Bruce Jensen |
#28
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Hi Lisa,
I, too, have an MFJ-1046 passive preselector. I use it in conjunction with an MFJ-959C Antenna Tuner/Preamp. As I live in an electrically quiet area about 35 miles WNW of Boston, I mostly do not need either of them, but they help pull out weak signals. More generally, there really are not a lot of preselectors out there anymore. Try visiting Yahoo Groups shortwave antennas http://groups.yahoo.com/group/Shortw...guid=257362530 Bob Betts has a preselector construction project that has been much discussed there. All best, Ed Bush Lisa Simpson wrote: This helped a lot. I ordered the MFJ956! "junius" wrote in message ups.com... Hi Lisa, I've used a number of MFJ preslectors in conjunction with a number of receivers. The most basic and inexpensive is the MFJ-956, recommended earlier in this thread by David. It's a decent, non-fussy little unit that really doesn't require too much re-tuning as you scan across a given band. The same can largely be said of the MFJ-1045C which I recently picked up from Grove. The 1045C, though, is an active preselector, so you'd have some gain added to your signal. I don't know that you'd necessarily want or need additional gain; I don't have any experience with the receiver you're working with. The 1045C runs off of an AC adapter or can be run off a 9 V battery. The option of running the unit off a battery can be nice if you ever take your receiver out into the field. Note: the 1045C is advertised on the websites of some retailers as being made to accomodate 2 receivers and 2 antennae. I called MFJ a week and a half back (prior to ordering a 1045C) and was informed by a tech at MFJ that the 1045C is designed for one antenna and one receiver: there are no radio 1/2 or antenna 1/2 switches as on the MFJ 1040C preselector (also distinguishing the two: the 1040C does not allow for 9V battery operation, and the 1040C is designed to permit use w/a transceiver). The 1045C looks a lot like the MFJ 1020C active antenna (which is sometimes advertised as being useful as an active preselector); the 1045C and 1020C are similar in appearance/layout of controls. According to the MFJ tech, though, the internals of the two are quite different and the 1045C is to be preferred where the preselection function is concerned. The other MFJ preselector to consider is the MFJ-1046, which is advertised as a "high dynamic range passive preselector". This was my first preselector and it remains the one I use most often. One thing I particularly like aobut it is that I've not noticed any signal loss in using it. And more often than not, I have no need for any amplification of the signal. This preselector is pretty narrow in its bandwidth, so it often requires a few small tuning adjustments as you tune across a given SW BC band. In any case, hope some of this helps. Junius Lisa Simpson wrote: Fishing for recommendations for antenna preselectors that would work well with a Radio Shack DX-394 & Eavesdropper C antenna . . . |
#29
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Best thing is an antenna farm and a box with enough jacks on it.Plug and
unplug like those old Western Electric telephone boards. cuhulin |
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