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Re: Elad S3 versus Perseus and FDM Duo
Conrad,
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FWIW I'm playing with the WinRadio Excelsior Ultra - now this is some receiver! https://www.winradio.com/home/g69ddce.htm This is quiet! Simon Brown, G4ELI https://www.sdr-radio.com
-----Original Message-----
From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Conrad, PA5Y Sent: 30 March 2022 15:28 To: main@SDR-Radio.groups.io Subject: Re: [SDR-Radio] Elad S3 versus Perseus and FDM Duo Hello Brian Yes sub 1dB noise figures definitely cost dynamic range.That is true and unnecessary, perhaps I misunderstand but you seem to be indicating that I am advocating sub 1dB noise figures on 144MHz. I am not and Chris Bartram was absolutely right. I said, earlier in the thread. ....... dynamic range is certainly not optional. I put systems together based upon total system analysis which includes both noise figure and dynamic range. On 2m with a 1dB NF which is a little better than needed for terrestrial operation in my semi-rural location. I use the free AppCAD program for system noise figure and dynamic range analysis, although a spreadsheet also works fine. I think that a system noise figure of 1dB on 2m is better than needed. I agree that 2dB is good enough for terrestrial use and even then only for the very fortunate. 1dB is slightly better than 2dB. For most people who are not on EME, these days 3-4dB is adequate for terrestrial use on 144 MHz due to manmade noise. Also in EU contests (including the UKAC) you are better off prioritising dynamic range much of the time. Which is why I use a step attenuator after the first LNA stage, I can adjust it extremely quickly depending on conditions. Try it, you will find that is optimal for the EU VHF DXer who suffers from high station density. By the way sub 1dB noise figures on 432MHz and above are very worthwhile and certainly not that difficult to achieve these days. 73 Conrad PA5Y -----Original Message----- From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Brian Morrison via groups.io Sent: 30 March 2022 14:52 To: main@SDR-Radio.groups.io Subject: Re: [SDR-Radio] Elad S3 versus Perseus and FDM Duo On Wed, 30 Mar 2022 11:22:30 +0000 "Conrad, PA5Y" <g0ruz@...> wrote: Yes sub 1dB noise figures definitely cost dynamic range.Back in the day (i.e. about 1979/80) Chris Bartam G4DGU of muTek determined that 144MHz system noise figures of less than 2dB for terrestrial signals were unnecessary due to the total noise at the antenna from sky and ground sources. The well-known muTek preamps were designed to have a NF of ~0.9dB (using a BF981 or 3SK88 FET with noiseless feedback) and then to allow a further 1dB contribution from the rest of the receiver to minimise any reduction in dynamic range. If you had the complete replacement muTek front-end which had a high-level diode-ring mixer, class A LO amplifier chain and post-mixer high IP3 IF amp then this DR reduction was much less but many of us had far less money then :(. I would not expect these external limitations to have changed in this regard over the intervening 40+ years, although the radios have become more expensive their performance has improved quite a bit in other respects. -- Brian G8SEZ -- - + - + - Please use https://forum.sdr-radio.com:4499/ when posting questions or problems. |
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Re: Default audio volume?
Max
I just had a quick look at the XML Favourites file export and see Simon says at top of file:
"The contents of this file must not be changed if the program is to operate correctly. To avoid problems, please do NOT edit this file." If you are not 100% comfortable with what you are doing then I suggest you stick to my first suggestion: Recall > Update > Re-Save each Favourite in turn that you wish to amend. Or use Simon's method of excluding the stored level when recalling from a Favourite. Untick "Apply Level": Max |
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Re: Default audio volume?
Max
On Thu, Mar 31, 2022 at 06:22 AM, D M wrote:
Can somebody tell me where can I set the default audio volume instead of the original default value of 50. Volume setting and also audio output source are both parameters stored with each Favourite. Or, as Simon says, you can exclude that parameter from recall if you wish.
See here:
https://www.sdr-radio.com/Favourites
To amend the stored value, easy route:
Recall Favourite, change volume setting, then "Update" Favourite.
To do all at once, using Favourites Organiser, export Favourites as XML. SAVE A SAFETY COPY.
Editing file in text editor (like Notepad), search for the volume parameter (sorry, I have not got time to search for what it is, but it will be pretty obvious) then "Find and Replace" for all or required entries. Then re-Import the amended Favourites file.
Hope it helps.
Max
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Keyboard shortcuts
Pierre FK8IH <jb.gallauziaux@...>
New to SDR-Console and having used before Quisk, is there a shortcut like the "space bar" to trigger the PTT? Is there also a way to change the frequency digit by digit but I recognize typing a figure then typing the frequency in the opened window is convenient?
73 - Pierre - FK8IH |
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Re: Default audio volume?
You can’t but look at:
Simon Brown, G4ELI
From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of D M via groups.io
Sent: 31 March 2022 06:22 To: main@SDR-Radio.groups.io Subject: [SDR-Radio] Default audio volume?
Can somebody tell me where can I set the default audio volume instead of the original default value of 50. When i jump around the the favorites frequencies it gets reset to 50 regardless to what I changed to earlier. Is it one of the xml files i need to tweak ? -- - + - + -
Please use https://forum.sdr-radio.com:4499/ when posting questions or problems.
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Default audio volume?
D M
Can somebody tell me where can I set the default audio volume instead of the original default value of 50. When i jump around the the favorites frequencies it gets reset to 50 regardless to what I changed to earlier. Is it one of the xml files i need to tweak ?
Thanks deep |
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Re: Elad S3 versus Perseus and FDM Duo
jdow
144 MHz and 445 MHz dynamic range around here is
simply unreal. LNAs have a wide bandwidth on their input,
typically. That means you are receiving some VERY weak signals.
Unfortunately pagers still exist. And around here pager
transmitters are in the kW region. Having one relatively nearby
can periodically desensitize a receiver in addition to creating
IMD products. With rtlsdr dongles this is easy to see here with
little whips depending on where I am tuned. AirSpy R2 dongles can
show it on frequencies too close to the pager frequency.
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{^_^} On 20220330 07:45:07, Brian Morrison
wrote:
On Wed, 30 Mar 2022 14:28:27 +0000 "Conrad, PA5Y" <g0ruz@...> wrote:That is true and unnecessary, perhaps I misunderstand but you seem to be indicating that I am advocating sub 1dB noise figures on 144MHz. I am not and Chris Bartram was absolutely right.I'm not Conrad, you're definitely correct in your earlier statements. Others seemed to be advocating lower noise figures in general, as you say there is a breakpoint somewhere above 200MHz where the sky and reflected ground noise falls off and at 70cm a 0.5dB NF is nice to have if you put the LNA at the correct place right next to your antenna. It's interesting that you say the DR needed on VHF is harder to achieve, but I suppose it must be due to the RMDRs due to the LO being worse at higher frequency. Stepped attenuators have their place, you just have to understand their effect which is not particularly difficult as it's just a normal cascaded NF/gain diagram and calculation. |
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Re: Elad S3 versus Perseus and FDM Duo
jdow
Of course, when you are up at 2 meters and above
(perhaps even 6 meters to a lesser degree) putting the LNA at the
antenna feed point gives you a "free" dB of noise figure
reduction. There is also a potential TX gain for putting the PA up
there, too.
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{^_-} On 20220330 07:28:27, Conrad, PA5Y
wrote:
Hello BrianYes sub 1dB noise figures definitely cost dynamic range.That is true and unnecessary, perhaps I misunderstand but you seem to be indicating that I am advocating sub 1dB noise figures on 144MHz. I am not and Chris Bartram was absolutely right. I said, earlier in the thread. ....... dynamic range is certainly not optional. I put systems together based upon total system analysis which includes both noise figure and dynamic range. On 2m with a 1dB NF which is a little better than needed for terrestrial operation in my semi-rural location. I use the free AppCAD program for system noise figure and dynamic range analysis, although a spreadsheet also works fine. I think that a system noise figure of 1dB on 2m is better than needed. I agree that 2dB is good enough for terrestrial use and even then only for the very fortunate. 1dB is slightly better than 2dB. For most people who are not on EME, these days 3-4dB is adequate for terrestrial use on 144 MHz due to manmade noise. Also in EU contests (including the UKAC) you are better off prioritising dynamic range much of the time. Which is why I use a step attenuator after the first LNA stage, I can adjust it extremely quickly depending on conditions. Try it, you will find that is optimal for the EU VHF DXer who suffers from high station density. By the way sub 1dB noise figures on 432MHz and above are very worthwhile and certainly not that difficult to achieve these days. 73 Conrad PA5Y -----Original Message----- From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Brian Morrison via groups.io Sent: 30 March 2022 14:52 To: main@SDR-Radio.groups.io Subject: Re: [SDR-Radio] Elad S3 versus Perseus and FDM Duo On Wed, 30 Mar 2022 11:22:30 +0000 "Conrad, PA5Y" <g0ruz@...> wrote:Yes sub 1dB noise figures definitely cost dynamic range.Back in the day (i.e. about 1979/80) Chris Bartam G4DGU of muTek determined that 144MHz system noise figures of less than 2dB for terrestrial signals were unnecessary due to the total noise at the antenna from sky and ground sources. The well-known muTek preamps were designed to have a NF of ~0.9dB (using a BF981 or 3SK88 FET with noiseless feedback) and then to allow a further 1dB contribution from the rest of the receiver to minimise any reduction in dynamic range. If you had the complete replacement muTek front-end which had a high-level diode-ring mixer, class A LO amplifier chain and post-mixer high IP3 IF amp then this DR reduction was much less but many of us had far less money then :(. I would not expect these external limitations to have changed in this regard over the intervening 40+ years, although the radios have become more expensive their performance has improved quite a bit in other respects. |
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Re: Frequency Database - Display Only Entries For Current Time ??
For my 2 cents worth, having a UTC
based time filter would be a great feature. Rather than seeing all
stations at a particular frequency, see only stations that "may"
be transmitting at a particular time would be much more useful.
On 3/30/2022 9:14 AM, John Dusek wrote: Yes, CSUB is exactly where I saw/used this concept the first time. |
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Re: Elad S3 versus Perseus and FDM Duo
Brian Morrison
On Wed, 30 Mar 2022 14:28:27 +0000
"Conrad, PA5Y" <g0ruz@...> wrote: That is true and unnecessary, perhaps I misunderstand but you seemI'm not Conrad, you're definitely correct in your earlier statements. Others seemed to be advocating lower noise figures in general, as you say there is a breakpoint somewhere above 200MHz where the sky and reflected ground noise falls off and at 70cm a 0.5dB NF is nice to have if you put the LNA at the correct place right next to your antenna. It's interesting that you say the DR needed on VHF is harder to achieve, but I suppose it must be due to the RMDRs due to the LO being worse at higher frequency. Stepped attenuators have their place, you just have to understand their effect which is not particularly difficult as it's just a normal cascaded NF/gain diagram and calculation. -- Brian G8SEZ |
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Re: Elad S3 versus Perseus and FDM Duo
Conrad, PA5Y
Hello Brian
Yes sub 1dB noise figures definitely cost dynamic range.That is true and unnecessary, perhaps I misunderstand but you seem to be indicating that I am advocating sub 1dB noise figures on 144MHz. I am not and Chris Bartram was absolutely right. I said, earlier in the thread. ....... dynamic range is certainly not optional. I put systems together based upon total system analysis which includes both noise figure and dynamic range. On 2m with a 1dB NF which is a little better than needed for terrestrial operation in my semi-rural location. I use the free AppCAD program for system noise figure and dynamic range analysis, although a spreadsheet also works fine. I think that a system noise figure of 1dB on 2m is better than needed. I agree that 2dB is good enough for terrestrial use and even then only for the very fortunate. 1dB is slightly better than 2dB. For most people who are not on EME, these days 3-4dB is adequate for terrestrial use on 144 MHz due to manmade noise. Also in EU contests (including the UKAC) you are better off prioritising dynamic range much of the time. Which is why I use a step attenuator after the first LNA stage, I can adjust it extremely quickly depending on conditions. Try it, you will find that is optimal for the EU VHF DXer who suffers from high station density. By the way sub 1dB noise figures on 432MHz and above are very worthwhile and certainly not that difficult to achieve these days. 73 Conrad PA5Y -----Original Message----- From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Brian Morrison via groups.io Sent: 30 March 2022 14:52 To: main@SDR-Radio.groups.io Subject: Re: [SDR-Radio] Elad S3 versus Perseus and FDM Duo On Wed, 30 Mar 2022 11:22:30 +0000 "Conrad, PA5Y" <g0ruz@...> wrote: Yes sub 1dB noise figures definitely cost dynamic range.Back in the day (i.e. about 1979/80) Chris Bartam G4DGU of muTek determined that 144MHz system noise figures of less than 2dB for terrestrial signals were unnecessary due to the total noise at the antenna from sky and ground sources. The well-known muTek preamps were designed to have a NF of ~0.9dB (using a BF981 or 3SK88 FET with noiseless feedback) and then to allow a further 1dB contribution from the rest of the receiver to minimise any reduction in dynamic range. If you had the complete replacement muTek front-end which had a high-level diode-ring mixer, class A LO amplifier chain and post-mixer high IP3 IF amp then this DR reduction was much less but many of us had far less money then :(. I would not expect these external limitations to have changed in this regard over the intervening 40+ years, although the radios have become more expensive their performance has improved quite a bit in other respects. -- Brian G8SEZ |
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Re: Frequency Database - Display Only Entries For Current Time ??
Yes, CSUB is exactly where I saw/used this concept the first time.
I remember back in the day using Ham Radio Deluxe (before it was sold), and it also did not have a filter on the frequency database function for current time - that's what originally had me research and find CSUB. This "filter for current time" feature would be a great feature to add to the existing Filter feature on the SDRC Frequency Database. |
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Re: Elad S3 versus Perseus and FDM Duo
Brian Morrison
On Wed, 30 Mar 2022 11:22:30 +0000
"Conrad, PA5Y" <g0ruz@...> wrote: Yes sub 1dB noise figures definitely cost dynamic range.Back in the day (i.e. about 1979/80) Chris Bartam G4DGU of muTek determined that 144MHz system noise figures of less than 2dB for terrestrial signals were unnecessary due to the total noise at the antenna from sky and ground sources. The well-known muTek preamps were designed to have a NF of ~0.9dB (using a BF981 or 3SK88 FET with noiseless feedback) and then to allow a further 1dB contribution from the rest of the receiver to minimise any reduction in dynamic range. If you had the complete replacement muTek front-end which had a high-level diode-ring mixer, class A LO amplifier chain and post-mixer high IP3 IF amp then this DR reduction was much less but many of us had far less money then :(. I would not expect these external limitations to have changed in this regard over the intervening 40+ years, although the radios have become more expensive their performance has improved quite a bit in other respects. -- Brian G8SEZ |
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Re: Elad S3 versus Perseus and FDM Duo
Conrad, PA5Y
Hi Joanne.
Yes sub 1dB noise figures definitely cost dynamic range. They are only necessary for moon-nbounce above 144MHz. Using celestial sources I have a system noise figure of 0.4dB on 432 which is not quite state of the art but the laws of diminishing returns have hit so I have decided to settle for this. It is very good for a yagi array and my on air results suggest that it must be close to optimum.
For the purposes of SDR usage and system design I have to settle for treating any SDR as a black box, there is nothing that I can do about this. I have to trust that Elad have chosen a optimal pre ADC op amp for the S3. As I have no test data from reputable 3rd parties I have to accept anecdotal evidence from users who I trust. I am mindful that the people responsible for the excellent Perseus are involved with the design of the S3. I will eventually do some tests myself.
I maintain that for VHF operating in Europe adding a step attenuator after a high dynamic LNA offers the most flexibility with the least consequences. As you say there is no free lunch but the system dynamic range loss is acceptable. It works in practice. I cannot change any of the subsequent stages on the fly, in fact I simply do not have the information nor time to do so. I fully understand the implications of what I am doing.
I have absolutely no feel for HF as I have no experience but VHF I know.
Regards
Conrad PA5Y
From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io>
On Behalf Of jdow via groups.io
What about the stages that follow? They are also stages that can limit dynamic range. (The most effective trick for the noise figure increase and dynamic range decrease was calculated years ago for CATV systems. It's a gain of "e", the
transcendental number. That is not the best from an economic standpoint, though. My spare time ham hacks through the 70s involved a lot of playing with noise figure, dynamic range, and receiver design to maximize this. It, too, falls victim to, "There Ain't
No Such Thing As A Free Lunch." Every stage you add reduces dynamic range for frequencies that manage to pass through the stage. That was a pain in the panties for the S3A sonobuoy receiver given its architecture. Fortunately their dynamic range requirement
as not at science fiction levels.
On 20220330 00:55:47, Conrad, PA5Y wrote:
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Re: Elad S3 versus Perseus and FDM Duo
On Tue, Mar 29, 2022 at 12:57 PM, Conrad, PA5Y wrote:
I have an XPOL system on 2m and most of the time I do not see much rotation but 6m is a completely different matter.The effect of Faraday rotation is proportional to the square of the wavelength! Ionospheric propagation is further complicated by changes in the path length of the wave in the ionosphere. Ionospheric radio reflection is not specular at a single point in the ionosphere but refracted over a significant distance which changes rapidly due to small fluctuations in density. Hence, the polarisation is always changing and often quite rapidly. John G4SWX |
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Re: Elad S3 versus Perseus and FDM Duo
Conrad PA5Y writes:
Actually a fully X-pol 50Mhz array will give you a distinct advantage on all ionospheric propagation modes. The suggestion of using a rotator on a Yagi, such as is sometimes used on 432MHz EME will not work on 50MHz due to the rapid changes in polarisation with time.
There has been a lot of recent research by Chris Deacon G4IFX and others. You can read a paper here:
Figure 1 shows quite clearly that Faraday rotation is changing in seconds rather than minutes as is the case on 144/432MHz EME Or even watch a video of Chris’ early work presented at the 2016 RSGB convention, introduced by the RSGB VHF manager……………
https://www.youtube.com/watch?v=13Cs4nB1TjI
John G4SWX |
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Re: Elad S3 versus Perseus and FDM Duo
jdow
At one point I considered two horizontal yagis spaced
appropriately for stacking. Then let the stacking boom rotate from
vertical to horizontal. That keeps the active antenna parts out of
the way of support metal. Even rotating the boom can have the
supports distort the pattern. With that configuration you can
balance the array and the polarization rotator to give a more
balanced load on the mast. Most configurations Ive seen in the
past seem to forget this potential balance trick.
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{^_^} On 20220330 00:58:15, Conrad, PA5Y
wrote:
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Re: Elad S3 versus Perseus and FDM Duo
jdow
What about the stages that follow? They are also
stages that can limit dynamic range. (The most effective trick for
the noise figure increase and dynamic range decrease was
calculated years ago for CATV systems. It's a gain of "e", the
transcendental number. That is not the best from an economic
standpoint, though. My spare time ham hacks through the 70s
involved a lot of playing with noise figure, dynamic range, and
receiver design to maximize this. It, too, falls victim to, "There
Ain't No Such Thing As A Free Lunch." Every stage you add reduces
dynamic range for frequencies that manage to pass through the
stage. That was a pain in the panties for the S3A sonobuoy
receiver given its architecture. Fortunately their dynamic range
requirement as not at science fiction levels.
toggle quoted message
Show quoted text
And, yes, 6 meters is fairly noisy. By 60s and even 70s standards the noise figures we get by default were considered exotic and low. Pushing for tiny noise figures (<1dB) on 2 is sort of pushing reality a little bit, and can really cost you with dynamic range. {^_^} On 20220330 00:55:47, Conrad, PA5Y
wrote:
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Re: Elad S3 versus Perseus and FDM Duo
Jim Smith G0OFE
Not necessarily. Many are horizontal or mixed. Holland, Ireland are mostly vertical. A n excellent site to use is FM LIst for transmitter info, and you can also see in real time what Band 2 DXers are logging,. If you need more pointers them mail me directly or join the SkywavesDX forum on SkywavesDX.org I also have the 8 ele Innovantennas, since
2013. I'd like to use a Korner 9.2 as it has better
front-to-back but it needs a bit of vertical space due to the
reflector array, and I'd have to sacrifice an additional antenna
for that.
================================
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 29/03/2022 19:51, Mag loop Simon
wrote:
Hi Conrad Yes most fm stations are vertical, but by time bounced a few times from “E” who knows polarisation.. Other Simon g0zen |
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Re: Frequency Database - Display Only Entries For Current Time ??
Max
On Tue, Mar 29, 2022 at 10:45 PM, John Dusek wrote:
I was hoping SDRC could emulate that current-time filtering bit, my current limited listening station only has one PC screen and is hard to fit a SDR with spectrum scope and CSVUserBrowser on a single screen in a usable manner,I agree it would be good if Simon could add a "current time" filter to the database. That would indeed be very useful. It's one of the best features of CSVUB and my guess is it would not be too difficult to implement in SDRC (spoken as a non-programmer!). Don't know if Simon is reading these posts at the moment as he is planting his tomatoes! Max |
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