I have a special antenna setup that allows me to receive VLF frequencies down to 20KHz. Believe or not, down that low, there are encrypted RTTY/MSK signals that are used by the Navy. I decided to try My K3S and it's "lowerfer" receive capabilities. With the K3S tuned to 292.681KHz, I was copying "M823 Differential GPS". Boring stuff but using a PC program called "Sorcerer", I was able to copy the data. It was also boring stuff but I wanted to test the K3S's VLF capabilities and the narrow filters allowed me to fine tune the MSK. My antenna was connected to the receiver-in port.
Jack WA9FVP
Sent from my home-brew I5 Core PC |
Is it possible, maybe in the next firmware rev, to extend the bottom end of the K3S down to 10KHz?
Jack WA9FVP
Sent from my home-brew I5 Core PC |
+1
Christian F1GWR Le 23 mars 2017 à 05:21, wa9fvp <[hidden email]> a écrit : > Is it possible, maybe in the next firmware rev, to extend the bottom end of > the K3S down to 10KHz? > > > > ----- > Jack WA9FVP > > Sent from my home-brew I5 Core PC > -- > View this message in context: http://elecraft.365791.n2.nabble.com/K3S-and-VLF-tp7628247p7628423.html > Sent from the Elecraft mailing list archive at Nabble.com. > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:[hidden email] > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to [hidden email] ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [hidden email] |
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I would love to see this but last I asked I was told No
From: wa9fvp <[hidden email]> To: [hidden email] Sent: Thursday, March 23, 2017 12:25 AM Subject: [Elecraft] K3S ELF 10KHz Is it possible, maybe in the next firmware rev, to extend the bottom end of the K3S down to 10KHz? ----- Jack WA9FVP Sent from my home-brew I5 Core PC -- View this message in context: http://elecraft.365791.n2.nabble.com/K3S-and-VLF-tp7628247p7628423.html Sent from the Elecraft mailing list archive at Nabble.com. ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [hidden email] ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [hidden email] |
In reply to this post by wa9fvp
Receivers THAT I AM AWARE OF begin coverage at 15 khz. Used to listen to
16 khz from GBR in England on an RAL when lived in Florida. After all, 10 khz -is- audio. 73 K0PP On Mar 22, 2017 22:22, "wa9fvp" <[hidden email]> wrote: > Is it possible, maybe in the next firmware rev, to extend the bottom end of > the K3S down to 10KHz? > > > > ----- > Jack WA9FVP > > Sent from my home-brew I5 Core PC > -- > View this message in context: http://elecraft.365791.n2. > nabble.com/K3S-and-VLF-tp7628247p7628423.html > Sent from the Elecraft mailing list archive at Nabble.com. > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:[hidden email] > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to [hidden email] > Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [hidden email] |
In reply to this post by wa9fvp
Wait a second, there's a big difference between a sound pressure wave and an electromagnetic wave at 10-kHz...
Myron WVØHPrinted on Recycled Data -------- Original message --------From: Ken G Kopp <[hidden email]> Date: 3/23/2017 7:41 AM (GMT-07:00) To: wa9fvp <[hidden email]>, [hidden email] Subject: Re: [Elecraft] K3S ELF 10KHz Receivers THAT I AM AWARE OF begin coverage at 15 khz. Used to listen to 16 khz from GBR in England on an RAL when lived in Florida. After all, 10 khz -is- audio. 73 K0PP On Mar 22, 2017 22:22, "wa9fvp" <[hidden email]> wrote: > Is it possible, maybe in the next firmware rev, to extend the bottom end of > the K3S down to 10KHz? > > > > ----- > Jack WA9FVP > > Sent from my home-brew I5 Core PC > -- > View this message in context: http://elecraft.365791.n2. > nabble.com/K3S-and-VLF-tp7628247p7628423.html > Sent from the Elecraft mailing list archive at Nabble.com. > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:[hidden email] > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to [hidden email] > Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [hidden email] ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [hidden email] |
In reply to this post by wa9fvp
I didn't understand the reference to audio either.
When I on the crew of a US ballistic missile submarine more than 40 years ago, our main communications receivers were AN/BRR-3 units whose full frequency range was only 14 to 30 kHz. These received signals from coastal stations operating at megawatt output levels, but there was no one near such a station with his ear drums damaged by or even sensitive to the station's continuous output. :-) Anyone can listen to such signals as they exist today. I'm not sure what the point would be...everything down there is very deeply encrypted. Mike / KK5F ------------------------------ >> Wait a second, there's a big difference between a sound pressure wave >> and an electromagnetic wave at 10-kHz... ------------------------------- > Receivers THAT I AM AWARE OF begin coverage at 15 khz. Used to listen to > 16 khz from GBR in England on an RAL when lived in Florida. > > After all, 10 khz -is- audio. ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [hidden email] |
Way back in ancient times I worked at a research lab where we had a LOT of receivers tuned to all the signals we could find below 60 kHz. I think the lowest was 13.x. There was an 18.x and 24.x etc. etc. We were only interested in signal strengths and plotted each signal on strip chart recorders, 24x7. It was very interesting working at those frequencies. (This was all part of a solar observatory project.)
So, I guess *that* would qualify as a reason to listen to this stuff.. 73, Doug, W7KF http://www.w7kf.com <http://www.w7kf.com/> > On Mar 23, 2017, at 4:03 PM, Mike Morrow <[hidden email]> wrote: > > I'm not sure what the point would be...everything down there is very deeply encrypted. ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [hidden email] |
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Yeah, I think they’re on 18.6 kHz — unless, of course, they managed to buy a VFO in the last 40 years!
Doug, W7KF > On Mar 23, 2017, at 4:45 PM, Ron D'Eau Claire <[hidden email]> wrote: > > The Jim Creek antenna facility is amazing - a series of over mile long wires > (cables) for the radiator strung from mountain to mountain across a valley > being fed with IIRC a megawatt of VLF RF. > > 73, Ron AC7AC ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [hidden email] |
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Doug,
Didn't the Navy use those frequencies to communicate with the submarines? I remember something about 30 KHz and an Atlantic Island and something Washington with a setup??? Long in the tooth ham! Mel K6KBE From: Doug Smith <[hidden email]> To: Elecraft Reflector <[hidden email]> Sent: Thursday, March 23, 2017 3:45 PM Subject: Re: [Elecraft] K3S ELF 10KHz Way back in ancient times I worked at a research lab where we had a LOT of receivers tuned to all the signals we could find below 60 kHz. I think the lowest was 13.x. There was an 18.x and 24.x etc. etc. We were only interested in signal strengths and plotted each signal on strip chart recorders, 24x7. It was very interesting working at those frequencies. (This was all part of a solar observatory project.) So, I guess *that* would qualify as a reason to listen to this stuff.. 73, Doug, W7KF http://www.w7kf.com <http://www.w7kf.com/> > On Mar 23, 2017, at 4:03 PM, Mike Morrow <[hidden email]> wrote: > > I'm not sure what the point would be...everything down there is very deeply encrypted. ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [hidden email] ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [hidden email] |
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Right. What is being transmitted is an electromagnetic field, NOT a
sound field. Sound is AIR (or water) vibrating. Sound waves travel a bit faster than a foot per msec. Sonar uses sound. The system Mike is talking about is radio. Radio is an electromagnetic field, which the simultaneous existence of an electric field and a magnetic field at right angles to each other, and they move through space at the speed of light. We can't hear radio waves, but we could hear high frequency sound waves if the radio waves were somehow detected (the trusty non-linear junction) and caused something to vibrate (or even to arc). 73, Jim K9YC On Thu,3/23/2017 3:03 PM, Mike Morrow wrote: > I didn't understand the reference to audio either. > > When I on the crew of a US ballistic missile submarine more than 40 years ago, our main communications receivers were AN/BRR-3 units whose full frequency range was only 14 to 30 kHz. These received signals from coastal stations operating at megawatt output levels, but there was no one near such a station with his ear drums damaged by or even sensitive to the station's continuous output.:-) > > Anyone can listen to such signals as they exist today. ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [hidden email] |
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Yup. Earlier in the thread Mike / KK5F pointed that out. He was on the RX end of the circuit.
We monitored stations from Perth, somewhere in the UK, east coast of USA, west coast of USA, etc. etc. Must have been six or eight stations on the air. We also monitored WWVB but I think that was the highest frequency (60 kHz) we cared about. It was all RTTY as I recall. We didn’t bother trying to decode the stuff — it was encrypted and we didn’t care about the content. We only cared about signal strength. Fun times; long time ago.. -Doug, W7KF > On Mar 23, 2017, at 4:55 PM, Mel Farrer <[hidden email]> wrote: > > Doug, > > Didn't the Navy use those frequencies to communicate with the submarines? I remember something about 30 KHz and an Atlantic Island and something Washington with a setup??? > > Long in the tooth ham! > > Mel K6KBE ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [hidden email] |
Years ago I had an Selective voltmeter and an signal generator I was surprised that the selective voltmeter could hear the signal generator across the room at what one would consider audio ranges. From: Doug Smith <[hidden email]> To: Mel Farrer <[hidden email]> Cc: Elecraft Reflector <[hidden email]> Sent: Thursday, March 23, 2017 7:15 PM Subject: Re: [Elecraft] K3S ELF 10KHz Yup. Earlier in the thread Mike / KK5F pointed that out. He was on the RX end of the circuit. We monitored stations from Perth, somewhere in the UK, east coast of USA, west coast of USA, etc. etc. Must have been six or eight stations on the air. We also monitored WWVB but I think that was the highest frequency (60 kHz) we cared about. It was all RTTY as I recall. We didn’t bother trying to decode the stuff — it was encrypted and we didn’t care about the content. We only cared about signal strength. Fun times; long time ago.. -Doug, W7KF > On Mar 23, 2017, at 4:55 PM, Mel Farrer <[hidden email]> wrote: > > Doug, > > Didn't the Navy use those frequencies to communicate with the submarines? I remember something about 30 KHz and an Atlantic Island and something Washington with a setup??? > > Long in the tooth ham! > > Mel K6KBE ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [hidden email] ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [hidden email] |
In reply to this post by Doug Smith [W7KF]
In the 80's using my Icom R71 receiver and a Burhans VLF converter, I copied the Omega Navigation system operating in the 10 to 12 KHz range. https://en.m.wikipedia.org/wiki/Omega_(navigation_system)
Jack WA9FVP
Sent from my home-brew I5 Core PC |
In reply to this post by Elecraft mailing list
We had an ELF transmitter site here in the U.P. of Michigan. Some
pictures and notes about the old location are on my cabin site. http://webpages.charter.net/aj8mh-radio/mich1.html 73, Joe ( AJ8MH-Radio ) On 3/23/2017 6:55 PM, Mel Farrer via Elecraft wrote: > Doug, > Didn't the Navy use those frequencies to communicate with the submarines? I remember something about 30 KHz and an Atlantic Island and something Washington with a setup??? > Long in the tooth ham! > Mel K6KBE > > ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [hidden email] |
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NLK[?] at Jim Creek used to transmit on 24.8 KHz with a megawatt or a
little more. I don't know if it is still active. The antenna is [was] a linear series of vertical elements down a valley, suspended by cables from the mountains on each side. I believe there were ten total, fed in two groups of 5 from two transmission lines on the valley floor. The suspension cables provided capacitive top loading, most of the radiation came from the vertical elements. Similar to the antenna at SAQ. Not much to listen to, it was [or still is] extreme QRSS. Just a handful of characters, often only one or two. The Omega system operated down in the 10-15 KHz range. The NA station was in one of the Dakotas, but it's been decommissioned for several decades. It wasn't much to listen to either. WWVL was on 20 KHz for awhile, gone now, and not much to listen to when it was on. I've "heard" WWVB on 60 KHz, pretty dull. At frequencies below 20 KHz, you don't need tubes or transistors, just a generator with a lot of poles and high RPM. Before LORAN-C on 100 KHz died, at least one of the stations was outfitted with an Accufix transmitter from Megapulse Corp. This was a late 20th Century re-incarnation of the spark gap TX ... SCR's for the spark gap, huge capacitor banks, around a megawatt, and precise timing from a room full of electronics. What goes around sometimes comes around. 73, Fred ("Skip") K6DGW Sparks NV USA Washoe County DM09dn On 3/23/2017 3:45 PM, Ron D'Eau Claire wrote: > The Jim Creek antenna facility is amazing - a series of over mile long wires > (cables) for the radiator strung from mountain to mountain across a valley > being fed with IIRC a megawatt of VLF RF. > > 73, Ron AC7AC > ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [hidden email] |
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