Date   

Re: Mystery Signal on 20-Meters

Kriss Kliegle KA1GJU
 

Looks like the 20M folks aren't going to be too happy this AM!



ouch!

73 Kriss KA1GJU


Re: Mystery Signal on 20-Meters

Jim Smith G0OFE
 

That's an interesting article.

Personally, my money is on this cycle being about the same or maybe 5-10% bigger than Cycle 24.. the "solar polar magnetic field at minimum" method has been pretty reliable in recent cycles for which this data is available. This new study is intriguing though.

================================
Need help with SDR Console? If you have a problem:
Go to https://www.sdr-radio.com/support
Please follow instructions in that link.
===================================
Jim, Bournemouth, Dorset. IO90BR.
Elad FDM-S2, Airspy HF+, SDRPlay and Funcube Dongle SDR Recievers
8-element OP-DES for Band 2, 8-element LFA for 2m, 3-element LFA for 6m, 20m Windom for HF,. Wellbrook 1530 Loop for LF


On 09/12/2020 09:06, jdow wrote:
I just ran across something that is likely to make this situation a lot livelier. It might also end up with the amateur allocations being "sold" to broadcasters who suddenly need new frequencies.

Some scientists and NCAR, the National Center for Atmospheric Research, believe they have identified a feature that allows for more accurate prediction of sunspot cycles. And they do not agree at all with NASA. Their predictions for the cycle just starting is that it will be very high and possibly record breaking high.

New Sunspot Cycle Could Be One Of The Strongest On Record, New Research Predicts

Don't you just LOVE ambiguity? Place your bets now, will this cycle be big or little?

{^_^}    (No, I am not making book.)


On 20201205 09:35:11, Brendan Wahl wrote:
Hi Roger,

I've not seen much 'new' info for sometime now. The frequencies in use are the most recent datapoints, and since this is private industry, they seem to be good at keeping all else fairly private. What is yet to be found is the use of this outside of US>EU paths, say AS>US. Taking advantage of the markets on a 24 hour basis with a faster order transmission system would seem to be desirable for trading firms all over the world. Money from milliseconds.

Brendan WA7HL


Re: Mystery Signal on 20-Meters

Allan Isaacs
 

Before you place your bets, there are a few clues here..  the words New, Research and Predicts. Much the same as Modelling …or Modeling depending on where you live, Guesswork and Stochastic and worst of all Stochastic Modelling…..  

 

I have fond memories of 1957 when we could receive Band I TV from all over the world in Liverpool. I even added a second diode in our TV so we could see pictures using opposite modulation.

Allan G3PIY


From: main@SDR-Radio.groups.io [mailto:main@SDR-Radio.groups.io] On Behalf Of jdow
Sent: 09 December 2020 09:06
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Mystery Signal on 20-Meters

 

I just ran across something that is likely to make this situation a lot livelier. It might also end up with the amateur allocations being "sold" to broadcasters who suddenly need new frequencies.

Some scientists and NCAR, the National Center for Atmospheric Research, believe they have identified a feature that allows for more accurate prediction of sunspot cycles. And they do not agree at all with NASA. Their predictions for the cycle just starting is that it will be very high and possibly record breaking high.

New Sunspot Cycle Could Be One Of The Strongest On Record, New Research Predicts

Don't you just LOVE ambiguity? Place your bets now, will this cycle be big or little?

{^_^}    (No, I am not making book.)

 


Re: Mystery Signal on 20-Meters

jdow
 

I just ran across something that is likely to make this situation a lot livelier. It might also end up with the amateur allocations being "sold" to broadcasters who suddenly need new frequencies.

Some scientists and NCAR, the National Center for Atmospheric Research, believe they have identified a feature that allows for more accurate prediction of sunspot cycles. And they do not agree at all with NASA. Their predictions for the cycle just starting is that it will be very high and possibly record breaking high.

New Sunspot Cycle Could Be One Of The Strongest On Record, New Research Predicts

Don't you just LOVE ambiguity? Place your bets now, will this cycle be big or little?

{^_^}    (No, I am not making book.)


On 20201205 09:35:11, Brendan Wahl wrote:
Hi Roger,

I've not seen much 'new' info for sometime now. The frequencies in use are the most recent datapoints, and since this is private industry, they seem to be good at keeping all else fairly private. What is yet to be found is the use of this outside of US>EU paths, say AS>US. Taking advantage of the markets on a 24 hour basis with a faster order transmission system would seem to be desirable for trading firms all over the world. Money from milliseconds.

Brendan WA7HL


Build Experimental Loop for LF to HF. Part 2 Extending the range

Paul Cianciolo
 

This is part 2 

Using series and parallel addition of the loop coils we can extend the range from 140KHZ to 2000KHZ 
Also adding fixed capacitance to get down below the EU longwave band.

https://youtu.be/MebhwNXv-6I


Re: Windows forgets its settings

John, G4DRS <g4drs@...>
 

I'm a twit. I forgot that this group is effectively defunct. I'll go to the forum with my question.
Sorry,


John
G4DRS


Windows forgets its settings

John, G4DRS <g4drs@...>
 

I use SDRC 3.0.25 as a panadapter, displaying the 9MHz IF of my FTdx5000. I use Logger32 as my logging software. SDRC is automatically launched when Logger32 starts up.
Sometimes, maybe once in every 4 or 5 start-ups, SDRC fires up full screen on monitor 1, instead of reduced size on monitor 2, as it was when closed down.
Is this normal, or am I doing something wrong?

73,
John
G4DRS


Re: CONSOLE and Bootcamp on MAC OS

JamesF_UK
 

One more thumbs up for running Simon's software under Bootcamp on my 2020 MacBook Pro... it's extremely stable, uses minimal CPU and looks great :)

I've use Macs for years at home and Windows-only machines at work and will always prefer using Windows on a Mac tbh!!

Just my 2p-worth.

James


Re: Build Experimental Loop for LF to HF.

Brent Seres/ VE3CUS
 

I use the LZ1AQ active loop. It's not tuned, but works really well.



Sent from my Galaxy


Re: Build Experimental Loop for LF to HF.

Allan Isaacs
 

A few comments to all that responded.

There are not many varicap diodes with enough swing to tune the VLF band. Using two back-to-back 1SV149 diodes would give me only 250pF so I’d need 8 to arrive at 1000pF from my two or 12 for my triple varicaps of 1500pF.

 

I did discover one rather useful side effect which was given enough amplification the thing would burst into oscillation (what used to be reaction in a TRF receiver) and just before this happened tuning selectivity increased dramatically as did the amplitude of a received signal. It will be fairly simple to add another FET across the buffer amplifier emitter resistor and use the spare wire in my cable to control reaction.

 

The main aim of the ferrite aerial over the loop was to reduce the physical size and to reduce the parasitic capacitance of the coils to give me a greater tuning range. The reason for trying both designs was to eliminate really bad local noise and another, particularly the new ferrite aerial is to help pinpoint the origin of local noise.

Allan G3PIY


From: main@SDR-Radio.groups.io [mailto:main@SDR-Radio.groups.io] On Behalf Of jdow
Sent: 06 December 2020 23:05
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Build Experimental Loop for LF to HF.

 

Another fun antenna to play with is the dielectric loaded flat spiral if you want to play at UHF for a REALLY broadband efficient antenna.

I took an antennas class in college. The professor was working on those things for use as patch antennas on aircraft to avoid extra drag.

{^_-}

On 20201206 14:38:21, Michael.2E0IHW via groups.io wrote:

A big loop is probably best for RX performance, but has to be, well, BIG -  and robustly built.
The Maynard derivatives, especially the ultralight DX series (search uldx io-group)  perform impressively,
but are heavy and, needing many ferrite rods,  expensive to build.

You takes yer choice...

Michael 2E0IHW

On 06/12/2020 17:59, jdow wrote:

My working levels came from a DoD receiver specification that was lying around. Take two signals into the receiver front end and vary their identical levels upwards until the 3rd order IMD products were 1uv - if I recall correctly. The test signal level in dBm plus 107 dB is the dynamic range. They were looking for 80 dB. (None of that ARRL horse manure about the sum of the levels - each signal was -27 dBm with IMD products at -127 dBm. So I was testing around -20 dBm to -30 dBm.

(And nothing really beats physical size for antennas. And a simple loop can easily be large enough that you need a LOT of ferrite to get equivalent performance. HOWEVER, there is the detail that if the antenna is 0.1% efficient at MW a bigger antenna will generally not give you better performance.)

{^_^}

On 20201206 09:30:02, Mag loop Simon wrote:

Hi
 
In my honest opinion..
 
Ferrite antennas are really down on sensitivity compared to tuned mag loops. ( tried it.)
 
 
Useful for dfing..but no one uses them for low noise dx Rx antennas..there is a good reason for this ..
 
Ok if one builds a ferrite antenna from LOTS of bars then they can start to be of use..but y? When can do much better with a rx only multi turn loop. ( less cost more Q etc.)
 
 
Re varicap diodes for tuning..been done for years..problem now is finding suitable diodes..and really they make any difference to imds etc with the small voltages developed across loop, ( unless real close to AM broadcast station etc.)
 
Main issue with remote high Q loop antennas is tuning..this can easy be got around with stepper motor..
 
I have alot of experience with loop antennas..I use a LARGE one for 160m tx..
 
Simon g0zen 
 

 


Re: Build Experimental Loop for LF to HF.

jdow
 

Another fun antenna to play with is the dielectric loaded flat spiral if you want to play at UHF for a REALLY broadband efficient antenna.

I took an antennas class in college. The professor was working on those things for use as patch antennas on aircraft to avoid extra drag.

{^_-}

On 20201206 14:38:21, Michael.2E0IHW via groups.io wrote:
A big loop is probably best for RX performance, but has to be, well, BIG -  and robustly built.
The Maynard derivatives, especially the ultralight DX series (search uldx io-group)  perform impressively,
but are heavy and, needing many ferrite rods,  expensive to build.

You takes yer choice...

Michael 2E0IHW

On 06/12/2020 17:59, jdow wrote:
My working levels came from a DoD receiver specification that was lying around. Take two signals into the receiver front end and vary their identical levels upwards until the 3rd order IMD products were 1uv - if I recall correctly. The test signal level in dBm plus 107 dB is the dynamic range. They were looking for 80 dB. (None of that ARRL horse manure about the sum of the levels - each signal was -27 dBm with IMD products at -127 dBm. So I was testing around -20 dBm to -30 dBm.

(And nothing really beats physical size for antennas. And a simple loop can easily be large enough that you need a LOT of ferrite to get equivalent performance. HOWEVER, there is the detail that if the antenna is 0.1% efficient at MW a bigger antenna will generally not give you better performance.)

{^_^}

On 20201206 09:30:02, Mag loop Simon wrote:
Hi

In my honest opinion..

Ferrite antennas are really down on sensitivity compared to tuned mag loops. ( tried it.)


Useful for dfing..but no one uses them for low noise dx Rx antennas..there is a good reason for this ..

Ok if one builds a ferrite antenna from LOTS of bars then they can start to be of use..but y? When can do much better with a rx only multi turn loop. ( less cost more Q etc.)


Re varicap diodes for tuning..been done for years..problem now is finding suitable diodes..and really they make any difference to imds etc with the small voltages developed across loop, ( unless real close to AM broadcast station etc.)

Main issue with remote high Q loop antennas is tuning..this can easy be got around with stepper motor..

I have alot of experience with loop antennas..I use a LARGE one for 160m tx..

Simon g0zen 




Re: sdr receiver 100khz to 1.7ghz

Bert Vierhout <bert.vierhout@...>
 

Have you to download and unpack zadig ? Zadig has more than one driver. One is suit for your rtl.

Bert



Verzonden vanaf mijn Galaxy


-------- Oorspronkelijk bericht --------
Van: Jerry Lofstead <glofstead@...>
Datum: 06-12-2020 23:23 (GMT+01:00)
Aan: main@sdr-radio.groups.io
Onderwerp: Re: [SDR-Radio] sdr receiver 100khz to 1.7ghz

Follow info on Simons site for RTL-SDR
Jerry
W3CDE

On Sun, Dec 6, 2020 at 3:46 PM Scott <scotthntr02@...> wrote:
hello there i purchased one of thease this week from china,ive plugged it in to the pc it does not respond.. contacted the seller they sent me software what dont work,ive tried other sites with software on but no joy ,im hopeing someone out there can send me a working software or a link to a site what will work ..or are thease obsalete now if anyone could help that be great thanks . 


Re: Build Experimental Loop for LF to HF.

Michael.2E0IHW
 

A big loop is probably best for RX performance, but has to be, well, BIG -  and robustly built.
The Maynard derivatives, especially the ultralight DX series (search uldx io-group)  perform impressively,
but are heavy and, needing many ferrite rods,  expensive to build.

You takes yer choice...

Michael 2E0IHW

On 06/12/2020 17:59, jdow wrote:
My working levels came from a DoD receiver specification that was lying around. Take two signals into the receiver front end and vary their identical levels upwards until the 3rd order IMD products were 1uv - if I recall correctly. The test signal level in dBm plus 107 dB is the dynamic range. They were looking for 80 dB. (None of that ARRL horse manure about the sum of the levels - each signal was -27 dBm with IMD products at -127 dBm. So I was testing around -20 dBm to -30 dBm.

(And nothing really beats physical size for antennas. And a simple loop can easily be large enough that you need a LOT of ferrite to get equivalent performance. HOWEVER, there is the detail that if the antenna is 0.1% efficient at MW a bigger antenna will generally not give you better performance.)

{^_^}

On 20201206 09:30:02, Mag loop Simon wrote:
Hi

In my honest opinion..

Ferrite antennas are really down on sensitivity compared to tuned mag loops. ( tried it.)


Useful for dfing..but no one uses them for low noise dx Rx antennas..there is a good reason for this ..

Ok if one builds a ferrite antenna from LOTS of bars then they can start to be of use..but y? When can do much better with a rx only multi turn loop. ( less cost more Q etc.)


Re varicap diodes for tuning..been done for years..problem now is finding suitable diodes..and really they make any difference to imds etc with the small voltages developed across loop, ( unless real close to AM broadcast station etc.)

Main issue with remote high Q loop antennas is tuning..this can easy be got around with stepper motor..

I have alot of experience with loop antennas..I use a LARGE one for 160m tx..

Simon g0zen 



Re: sdr receiver 100khz to 1.7ghz

Jerry Lofstead W3CDE
 

Follow info on Simons site for RTL-SDR
Jerry
W3CDE

On Sun, Dec 6, 2020 at 3:46 PM Scott <scotthntr02@...> wrote:
hello there i purchased one of thease this week from china,ive plugged it in to the pc it does not respond.. contacted the seller they sent me software what dont work,ive tried other sites with software on but no joy ,im hopeing someone out there can send me a working software or a link to a site what will work ..or are thease obsalete now if anyone could help that be great thanks . 


Re: sdr receiver 100khz to 1.7ghz

Alan G4ZFQ
 

Scott
i purchased one of thease this week from china,
It would help if you named this device.
And it might help if you said what driver/software was supplied with it.
And maybe what actually happened when you tried.

Alan


sdr receiver 100khz to 1.7ghz

Scott <scotthntr02@...>
 

hello there i purchased one of thease this week from china,ive plugged it in to the pc it does not respond.. contacted the seller they sent me software what dont work,ive tried other sites with software on but no joy ,im hopeing someone out there can send me a working software or a link to a site what will work ..or are thease obsalete now if anyone could help that be great thanks . 


Re: CONSOLE and Bootcamp on MAC OS

chipbutty
 

I know this is an old thread but I'm running the latest version of Simon's excellent software under Bootcamp on an antique 2011 MacBook Pro. Runs great. I also have it running on my 2015 iMac. I've used both WIndows and Macs for thirty years but could never stand Windows. I'm also a keen photographer so maybe it's just the way we're wired up!

I absolutely love my overpriced Macs ;-) 


Re: Build Experimental Loop for LF to HF.

jdow
 

My working levels came from a DoD receiver specification that was lying around. Take two signals into the receiver front end and vary their identical levels upwards until the 3rd order IMD products were 1uv - if I recall correctly. The test signal level in dBm plus 107 dB is the dynamic range. They were looking for 80 dB. (None of that ARRL horse manure about the sum of the levels - each signal was -27 dBm with IMD products at -127 dBm. So I was testing around -20 dBm to -30 dBm.

(And nothing really beats physical size for antennas. And a simple loop can easily be large enough that you need a LOT of ferrite to get equivalent performance. HOWEVER, there is the detail that if the antenna is 0.1% efficient at MW a bigger antenna will generally not give you better performance.)

{^_^}

On 20201206 09:30:02, Mag loop Simon wrote:
Hi

In my honest opinion..

Ferrite antennas are really down on sensitivity compared to tuned mag loops. ( tried it.)


Useful for dfing..but no one uses them for low noise dx Rx antennas..there is a good reason for this ..

Ok if one builds a ferrite antenna from LOTS of bars then they can start to be of use..but y? When can do much better with a rx only multi turn loop. ( less cost more Q etc.)


Re varicap diodes for tuning..been done for years..problem now is finding suitable diodes..and really they make any difference to imds etc with the small voltages developed across loop, ( unless real close to AM broadcast station etc.)

Main issue with remote high Q loop antennas is tuning..this can easy be got around with stepper motor..

I have alot of experience with loop antennas..I use a LARGE one for 160m tx..

Simon g0zen 





Re: Build Experimental Loop for LF to HF.

jdow
 

The precise circuit used can make a lot of difference. Back to back diodes can perform much better than a single diode. It can also bend your head out of shape when you try to measure IMD performance if you feed the diode junction with a resistor. An inductor works better in terms of screwing with your mind when measuring it. For single ended it's a natural configuration. For back to back diodes this creates an interesting parasitic resonance you want to account for. That was the circuit that I modeled before building. The tech who built it was really good. Measured results and my circuit analysis tool proved to be almost overlays. That success proved to me there is merit to the dark side, the bit part players on the analog stage.

You get best results running with high voltage diodes at as high a bias voltage as possible. But that limits your voltage range. Build and measure becomes your mantra. These days "build" can happen in a circuit analysis tool if it models devices deeply enough (and you have lots of time for thumb twiddling with the computer thinks.)

{^_^}

On 20201206 06:03:12, Allan Isaacs wrote:

Interesting, but do the advantages outweigh the disadvantages?

The fact that you’re tuning a specific signal with a significant degree of selectivity means that you’re unlikely to notice the effects of a strong out of band signal? If you do get problems you can null out the unwanted signal by turning the ferrite rod. The end result will be much the same as using a portable radio with its ferrite rod.

Would switching diodes used in some front ends have much the same problem?

 

I’ll do some experiments when I have time.

I suppose if the aerial coil is tuned to a really strong SSB signal the varicap voltage will swing a little and widen the tuning response curve?

 

Allan G3PIY

 


From: main@SDR-Radio.groups.io [mailto:main@SDR-Radio.groups.io] On Behalf Of jdow
Sent: 06 December 2020 12:49
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Build Experimental Loop for LF to HF.

 

How do you keep the varicap from causing all manner of IMD, some of it pretty exotic? Don't forget that the tuning voltage is "modulated" by the signal voltages in the tuned circuit.

{o.o}

On 20201206 02:19:50, Allan Isaacs wrote:

Hi Paul

Try a varicap and a ferrite rod.

A lot easier to handle and you do not need a ladder to adjust it when on top of a pole.

http://www.radiomuseum.co.uk/active.html

Allan G3PIY

 



Re: Build Experimental Loop for LF to HF.

Mag loop Simon
 

Hi

In my honest opinion..

Ferrite antennas are really down on sensitivity compared to tuned mag loops. ( tried it.)


Useful for dfing..but no one uses them for low noise dx Rx antennas..there is a good reason for this ..

Ok if one builds a ferrite antenna from LOTS of bars then they can start to be of use..but y? When can do much better with a rx only multi turn loop. ( less cost more Q etc.)


Re varicap diodes for tuning..been done for years..problem now is finding suitable diodes..and really they make any difference to imds etc with the small voltages developed across loop, ( unless real close to AM broadcast station etc.)

Main issue with remote high Q loop antennas is tuning..this can easy be got around with stepper motor..

I have alot of experience with loop antennas..I use a LARGE one for 160m tx..

Simon g0zen

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