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Yahoo Shortwave Radios Group
I've joined several Yahoo shortwave groups over the past week. Degen,
Tecsun, Sony, etc., all have some great information. The Yahoo Shortwave Radios group has me puzzled though. I completed the information sheet last week and I still can't get in. Yahoo says "Your membership is awaiting approval by the group owner". It must be quite an exclusive shortwave radio club to require that much of a background check. Thinking back over all the forums, nets, bbses, etc., I've belonged to over the years I've never had a forum owner limit access...usually they welcome it. |
Some moderators are just plain lazy. Like the VR-5000 group. It can take
up to a week for your post to show up. If you question this or ask other similar questions, they don't show up AT ALL... wrote in message ps.com... I've joined several Yahoo shortwave groups over the past week. Degen, Tecsun, Sony, etc., all have some great information. The Yahoo Shortwave Radios group has me puzzled though. I completed the information sheet last week and I still can't get in. Yahoo says "Your membership is awaiting approval by the group owner". It must be quite an exclusive shortwave radio club to require that much of a background check. Thinking back over all the forums, nets, bbses, etc., I've belonged to over the years I've never had a forum owner limit access...usually they welcome it. |
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And a couple of hours after posting this I now have access.
John prostrates himself on the temple floor and reverently chants: Oh Thank You Gods of Yahoo!!! Jim Hackett wrote: Some moderators are just plain lazy. Like the VR-5000 group. It can take up to a week for your post to show up. If you question this or ask other similar questions, they don't show up AT ALL... wrote in message ps.com... I've joined several Yahoo shortwave groups over the past week. Degen, Tecsun, Sony, etc., all have some great information. The Yahoo Shortwave Radios group has me puzzled though. I completed the information sheet last week and I still can't get in. Yahoo says "Your membership is awaiting approval by the group owner". It must be quite an exclusive shortwave radio club to require that much of a background check. Thinking back over all the forums, nets, bbses, etc., I've belonged to over the years I've never had a forum owner limit access...usually they welcome it. |
Chapter III. I posted a response to a question about antenna tuners
yesterday. So far it hasn't shown up on the Yahoo Shortwave Radios forum. I think I may have run afoul of another forum rule though. A section of the welcoming email to that forum indicated that responses to forum members had to be sent to an email address. Apparently responses are not allowed to be directly posted by members. I'm hoping that the forum owner will clarify things in his response to my email. Hopefully it was either some misunderstanding on my part or a poorly worded message on theirs. I've never had to jump through so many hoops to just read messages and post a response. I'm trying to respond to the age-old question: Do antenna tuners really help SWL's. Nothing inflamatory..... |
HJS,
.. If you had a Shortwave Listener (SWL) Antenna ? Question ? . .. You should have posted it here on "Rec.Radio.Shortwave". RRSWL= http://groups-beta.google.com/group/...dio.shortwave/ .. Or - On the Shortwave Listener (SWL) Antenna eGroup on YAHOO ! SWL-ANTENNAS= http://groups.yahoo.com/group/Shortwave-SWL-Antenna/ .. Usually whether here or there; you will get someone who will Throw-a-Rock-at-the-Barn {Answer/Reply} within a Day and often have an answer/reply within Hours. .. Also - You could try "Rec.Radio.Amateur.Antenna" for some of your Antenna Questions: If you are willing to get a bit more 'Technical' about the Subject of "Antennas". RRAA= http://groups-beta.google.com/group/...ateur.antenna/ .. iane ~ RHF .. All are WELCOME at the Shortwave Listener (SWL) "Antenna Ashram" http://groups.yahoo.com/group/Shortw...na/message/502 Some Say: On A Clear Day You Can See Forever. I BELIEVE: On A Clear Night . . . You Can Hear Forever and Beyond, The BEYOND ! [ With the a SWL Antenna of your own making. ] .. .. |
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Hmmm...my experience is different. With a reasonably quiet receiver my
experience has been that a tuner brings both ambient noise and the desired signal up equally in strength. Since background noise is usually greater than the receiver noise level, a tuner functions more like a volume control. |
I too have found a tuner will bring up the signal strength for Radio
Flyspeck to a nice level. But it will also being up static and other signals on the same frequency in proportion. I don't know how a tuner could select one signal and lift it above all the other competing transmissions on the same frequency. Transmit is of course a whole 'nuther ballgame. |
wrote: I too have found a tuner will bring up the signal strength for Radio Flyspeck to a nice level. But it will also being up static and other signals on the same frequency in proportion. I don't know how a tuner could select one signal and lift it above all the other competing transmissions on the same frequency. Transmit is of course a whole 'nuther ballgame. It doesn't, but I can see that you're missing the point! If ones antenna has such a bad mismatch that you can't actually hear Radio Flyspeck very well and an antenna tuner will bring it up to a better level then that's great. Forget about noise, that's a popular misconception as far as I'm concerned. Noise is noise is noise. Oh well. All I know about is what has been successful for myself, your mileage may vary, as they say. dxAce Michigan USA http://www.iserv.net/~n8kdv/dxpage.htm |
wrote: I too have found a tuner will bring up the signal strength for Radio Flyspeck to a nice level. But it will also being up static and other signals on the same frequency in proportion. I don't know how a tuner could select one signal and lift it above all the other competing transmissions on the same frequency. Transmit is of course a whole 'nuther ballgame. And no, transmit in not a whole 'nuther ballgame. The same properties apply to a transmitted signal as it does to a received signal. It's physics. Proper transfer is proper transfer, no matter which way one tries to figure it. dxAce Michigan USA http://www.iserv.net/~n8kdv/dxpage.htm |
MK,
The 'tuner' simply "Optimizes" the MATCH between the Receiver and/or Transmitter and the Antenna and Feed-Line; since most 'tuners' are near the Receiver and/or Transmitter. Both Signal and Noise are transfered equally. For 'noise reduction' look to modifying your Antenna, Feed-Line and Ground [System] to maintain or improve your signal levels; and reduce your noise levels. .. kisap ~ RHF .. .. |
The issue, or question is whether an antena tuner can selectively
increase one signal within the mishmash of other stuff you are hearing. If you receiver is hearing an ambient noise level that is above the internally noise floor within the receiver then an antenna tuner will only bring that ambient noise leveI up. If you were hearing Radio Fly Speck against a background of static and weaker stations, then adjusting an antenna tuner will increase the signal strength of everything including RFS. It won't magically lift just that single station from the mud. Said another way it isn't possible for a tuner change the difference in signal strength between the desired signal and all the other signals that are competing for your ear on the same frequency. I've tried both MFJ and Grove tuners and the end results were the same. Tuners can be fun if you want to twiddle some knobs. |
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The issue, or question is whether an antena tuner can selectively
increase one signal within the mishmash of other stuff you are hearing. If you receiver is hearing an ambient noise level that is above the internally noise floor within the receiver then an antenna tuner will only bring that ambient noise leveI up. If you were hearing Radio Fly Speck against a background of static and weaker stations, then adjusting an antenna tuner will increase the signal strength of everything including RFS. It won't magically lift just that single station from the mud. Said another way it isn't possible for a tuner change the difference in signal strength between the desired signal and all the other signals that are competing for your ear on the same frequency. I've tried both MFJ and Grove tuners and the end results were the same. Tuners can be fun if you want to twiddle some knobs. |
In article .com,
wrote: The issue, or question is whether an antena tuner can selectively increase one signal within the mishmash of other stuff you are hearing. If you receiver is hearing an ambient noise level that is above the internally noise floor within the receiver then an antenna tuner will only bring that ambient noise leveI up. If you were hearing Radio Fly Speck against a background of static and weaker stations, then adjusting an antenna tuner will increase the signal strength of everything including RFS. It won't magically lift just that single station from the mud. But if some of that noise is intermod in your receiver because of nearby strong signals, a preselector may help. A better receiver will, too. Said another way it isn't possible for a tuner change the difference in signal strength between the desired signal and all the other signals that are competing for your ear on the same frequency. I've tried both MFJ and Grove tuners and the end results were the same. Tuners can be fun if you want to twiddle some knobs. I've got a Grove minituner-tun3, and it's useless above about 2 MHz with a 60 foot or so random wire. But it's the only way to get anything on that wire below 500 kHz. So it's real function seems to be matching a short (relative to the signal's wavelength) high impedance antenna to the receiver's 50 ohm input. Mark Zenier Washington State resident |
You've missed the point, as I stated earlier! I use an antenna tuner also. An old Johnson Matchbox. Yes, it indeed will raise up a very week signal which may not even be audible without a tuner. What is occurring is that the tuner will facilitate the transfer of energy from a large impedance (Z) mismatch between the antenna and the receiver when the receiver is tuned far off from the antenna's resonance frequency. The drawback is that you will have to "tune" the tuner each time you change bands. It has nothing to do with static and noise. The tuner will simply optimize the signal transfer , including noise, between the antenna/feedline and receiver. Sometimes this is all that may be required to "hear" the signal which otherwise would be completely lost from the large impedance mismatch. |
If you receiver is hearing an ambient noise level that is above the
internally noise floor within the receiver then an antenna tuner will only bring that ambient noise leveI up. True. If you were hearing Radio Fly Speck against a background of static and weaker stations, then adjusting an antenna tuner will increase the signal strength of everything including RFS. It won't magically lift just that single station from the mud. True. Said another way it isn't possible for a tuner change the difference in signal strength between the desired signal and all the other signals that are competing for your ear on the same frequency. True. However you are missing one more possibility. That is the impedance mismatch between the antenna and receiver is so great that you cannot hear Radio Fly Speck at all. This impedance mismatch is akin to placing an attenuator in-line with your feedline. In which case the tuner will "tune out" the loses caused by the mismatch and allow Radio Fly Speck to rise above the receiver's noise level. Including the static crashes to of course. But there you are - Fly Speck Radio becomes audible. Works for me! |
tianli wrote: You've missed the point, as I stated earlier! I use an antenna tuner also. An old Johnson Matchbox. Yes, it indeed will raise up a very week signal which may not even be audible without a tuner. What is occurring is that the tuner will facilitate the transfer of energy from a large impedance (Z) mismatch between the antenna and the receiver when the receiver is tuned far off from the antenna's resonance frequency. The drawback is that you will have to "tune" the tuner each time you change bands. It has nothing to do with static and noise. The tuner will simply optimize the signal transfer , including noise, between the antenna/feedline and receiver. Sometimes this is all that may be required to "hear" the signal which otherwise would be completely lost from the large impedance mismatch. Yep, you got it! dxAce Michigan USA |
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