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Messages - EliteData

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106
Other / MARS on HF 6.897.5 USB
« on: February 03, 2016, 1815 UTC »
been listening to these guys for awhile and an operator mentioned a website to download software that encodes/decodes the data that they send between themselves (Automated Message Terminal) - thought i would share this info
Automated Message Terminal software - http://aar3hb.com/amt/

107
at work today, logged on via sdr-radio.com and websdr.org, it appears there are two carriers, one on AM, the other on USB, it seems the AM one is repeating the USB one ?  ??? weird  ???
edit: i think its the USB repeating the AM or maybe both are transmitting the same thing, this is confusing but there are definitely two carriers there

109
SSTV at 0142 with email address unidradio@gmail.com

UNIDradio@gmail.com -  :D someone just had to do it  :D

110
it appears to be reduced carrier USB with a buzzing of some type

111
The problem with FM is the amount of power required for good reception.  I did some tests a few years ago with an HP broadband generator and concluded that the bandwidth needed was just too wide for our little chunk of spectrum.  For good fidelity, I needed close to 40KHz of bandwidth or so, and that would probably upset some folks.  2KW or so would probably give nice coverage coast to coast...

+-RH
and obviously opening up the receiver bandwidth to 40Khz drops sensitivity but increases fidelity (and adjacent interference).
it is possible to "cram" the audio spectrum up to 10Khz though, you obviously wont get hi-fi sound but it will be similar and comparable to commercial SW broadcasts that utilize 10Khz (5Khz each side band), it just requires lots of "fine tuning".
in general, it not really worth it for purposes of broadcasting unless the general audience listening will be using specialized SDR receivers capable of allowing the full AF spectrum being only limited to the bandwidth filter itself.
this same AF spectrum issue exists for receivers using USB/LSB but not for DSB and not for AM though DC is filtered on AM, USB and LSB, DC is not filtered on DSB.
i totally agree with you that you would require more RF power to achieve the same results though.
as it goes for anything, the more bandwidth you use, the more power you need.

112
MW Loggings / Re: Finally TA MW :)
« on: January 19, 2016, 1059 UTC »
1660 WWRU New Jersey says on web that it has moved to FM. But here I am listening to a Korean show with Kenny Rogers music on 1660 like nothing has happened.

Hopefully conditions keep improving during this week and sun keeps peaceful. 
i would think if they moved to FM, they would still use the MW transmitter and "lease air time".

113
Just happened across this... the 9955khz broadcast from Florida in English is being jammed by Cuba???  I believe this is from the Okeechobee USA station. Standard Christian material NOT propaganda...  time 0215 UTC   
ive actually run into quite a few AM broadcasts above 7.2Mhz being jammed/interfered with DSB or a similar modulation of what sounded like "white noise" and didnt really think anything of it, because between 7.2Mhz and 7.6Mhz, has utility and SWBC mixed together.
i thought jamming on SW was over and done with after the "cold war" ended.

114
I like the AM mode best, SSB the least but why have I not heard NBFM being used in the 6900-6990 band... ?

Now I'm not in anyway encouraging anyone to do anything illegal but still.  I remember a number of years ago Amateur Radio Operators using that mode on the 75 meter band and it worked out great for the times they used it

Most modern radio gear does have NBFM detectors and even the older radios that don't can still hear the transmissions via 'slope detection'.  Slope detection is nothing more than tuning a receiver in the AM mode slightly above or below the center carrier frequency. 

Am I not thinking clearly because it is so early in the morning...  most likely... <sigh> Never mind...  ::)

 
FM could work easily if the operator modifies or builds a modulator that is capable of a frequency response 20Hz-20Khz, its quite easy to do.
most transceivers (not home brew) have audio circuits with "curved", limited audio response and modulation, with a diagram and knowledge, you can easily "bypass" those circuits.
the problem lies in two areas, first, limiting the correct amount of each audio frequency to a specified deviation for FM, second, some listener receivers including SDR receivers, have a low frequency cutoff filter at 70Hz or higher, the high frequency response is dependent on the receive bandwidth setting of the user or radio.
ive tested FM at a deviation of 10Khz with excellent audio response up to 10Khz with very good results using various radio receivers and SDR receivers.
to get the best AF response from an SDR receiver requires disabling any audio filters present besides the bandwidth filter (SDR sharp has this ability).
while disabling the audio filter on an SDR receiver can produce excellent AF response results, there is a couple of caveats, on AM, the DC from the carrier will be present in the audio and any slight distortion from over modulation in the broadcast will be emphasized (especially AM).
the key is to strictly limit all audio frequencies by using a 12 band audio compressor/limiter/clipper and a HF AF bandwidth filter when transmitting.
while the FM modulation may be a bit low, it will have the same fidelity as 10Khz AM with less static (on a good signal) and QRM.
the additional benefit is that you can operate full carrier and not worry about carrier saturation on AM transmit.

115
North American Shortwave Pirate / Re: UNID 6925 USB 2119 UTC 1/18/16
« on: January 18, 2016, 2144 UTC »
Same here with the movie audio and CW at 2120 UTC. S5 here. Off briefly at 2123 UTC, then both back at the same time at 2124 UTC
2135 UTC There were at least 3 separate CW ops at the same time....don't see the point of this... ???
ive been listening to this while at work (remotely) and lately, 6925 is a wild jungle of strange sounds and strange signals  :D but the entertainment value is certainly worth while  ;D

116
North American Shortwave Pirate / Re: UNID 6925 USB 2119 UTC 1/18/16
« on: January 18, 2016, 2138 UTC »
sounds like a CW fest.
im receiving 3 active CW's with one of them "SOS" and "CQDX" over and over.

117
Utility / Re: Fax From Chile ? 6943.8 0352 UTC 16 Jan 2016
« on: January 16, 2016, 1753 UTC »
reverse image through the internet provided a similar result.
right on the money Chris !

118
Hey JCMaxwell....you take the pudding....I'm sticking with the Spam! :D

Livermush is a Southern United States food product composed of pig liver, head parts, and cornmeal. It is commonly spiced with pepper and sage. Though sometimes considered the same as liver pudding, livermush (or liver mush) is generally coarser in texture and commonly found in the western part of North Carolina. It normally has a different recipe from liver pudding, though the distinction is blurred.

It is commonly cooked by cutting a slice off of a premade loaf and frying it with grease in a skillet until golden brown, similar to the way Spam is prepared. At breakfast it is served alongside grits and eggs. For lunch it can be made into a sandwich with mayonnaise or mustard, either fried as above, or left cold. As livermush's popularity has risen, it has appeared as an ingredient in dishes such as omelettes and pizzas.
Shelby, North Carolina hosts an annual Livermush Exposition, which began in 1987 to celebrate the unique delicacy. In that year the Cleveland County Commissioners and the Shelby City Council passed resolutions proclaiming that "livermush is the most delicious, most economical and most versatile of meats." Other towns in North Carolina that have livermush festivals include Drexel and Marion

ive had this and its really not bad at all, better than "potted meat product".

119
FM Free Radio / Re: faint signal @ 87.740mhz in NY
« on: January 15, 2016, 2302 UTC »
Elite - like you, I reside here in pukey New York State.  When I have occasionally dabbled on the FM band, I ALWAYS stay below 88 MHz.  I do that because the quirky way that the New York Anti-Radio Piracy law is written, the state has no jurisdiction below 88 MHz.  Better to dog the overworked Feds than the NYS Troopers.  I'm guessing that your neighbor is down there for similar reasons...
correct.
NYS only has jurisdiction on the fm & am broadcast bands from 88-108 & 530-1700 respectively.
http://www.engineeringradio.us/blog/2011/06/new-york-state-passes-anti-pirate-radio-law-s-5739-a-326/

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