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How close to a carrier I can get? Many Hams, educators and me would like to see and check their modulators. That is, can I see what does spectrum of? SSB with 1kHz modulation look like. Or 300Hz and closer.
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AS the minimum RBW is 2.7kHz you can not "See" you modulation?
For that you best use a receiver and a PC with line in.
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To measure close in products you need a much narrower RBW typical is
30-100hz, maybe 300hz.? You also need to insure the carrier if any is
not overloading the input of the SA.
If true SSB source and no distortion there is only one signal that being the
sum or difference of the carrier and some carrier leakage which for any
competent system should be at least -40dbc or better.
Its easy to do but you need a suitably narrow bandwidth system.
Allison
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Please post here, direct emails go to a dead letter box.
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Or use a SDR receiver as a poor man SA. You can see modulation sidebands and splatter very well in the waterfall display. You can use really small BWs.
Regards,
Ignacio EB4APL
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El 08/05/2020 a las 8:08, erik@... 别蝉肠谤颈产颈ó: AS the minimum RBW is 2.7kHz you can not "See" you modulation
For that you best use a receiver and a PC with line in.
--
El software de antivirus Avast ha analizado este correo electrónico en busca de virus.
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Can you recommend one/a few which can do that? I have not found a SDR which could do that.
Leif
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?Use any web sdr.
Most have a waterfall option.
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All true. I would check FM, DSB and what ever there is.
Modulation would be easier understand with a suitable SA.
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Hi Leif If you are ready to invest a bit then look at and purchase one of these models. Then you have a first call SDR Radio and secondly by downloading the Spectrum Analyzer software on this link ? . On this page The SDR Uno software is also to download which is the software for SDR Radio application. The are several other SDR radio software which is supporting the various SDRPlay units. For a lower budget and get started above 50MHZ then anumber of low cost USB stick can be used and then visit the ? where there is a lot of information to study Look also under the supported software And for the USB dongles Good luck Kind regards Kurt ? ? Can you recommend one/a few which can do that? I have not found a SDR which could do that.
Leif
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Kurt,
How about that? I own a RSP1, compatible with?
?.
This will be great to compare to our soon-to-be-loved-tinySA :D?
QRV @ 145.300 MHz |?CQ0VMST (VHF REP Monsanto)
On Fri, 8 May 2020 at 22:39, Kurt Poulsen < kurt@...> wrote: Hi Leif If you are ready to invest a bit then look at and purchase one of these models. Then you have a first call SDR Radio and secondly by downloading the Spectrum Analyzer software on this link ? . On this page The SDR Uno software is also to download which is the software for SDR Radio application. The are several other SDR radio software which is supporting the various SDRPlay units. For a lower budget and get started above 50MHZ then anumber of low cost USB stick can be used and then visit the ? where there is a lot of information to study Look also under the supported software And for the USB dongles Good luck Kind regards Kurt ? ? Can you recommend one/a few which can do that? I have not found a SDR which could do that.
Leif
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Hi Luis Sure. I Got two off them ? I have not experaince with it apart form the who wrote about the combo. I will of course fire it up. I will however mainly compare to my R&S CMU200/CRTU-RU above 10MHz which has BW down to 10Hz Kind regards Kurt ? Kurt, How about that? I own a RSP1, compatible with? ?. This will be great to compare to our soon-to-be-loved-tinySA :D?
? QRV @ 145.300 MHz |?CQ0VMST (VHF REP Monsanto) ? ?
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On Fri, 8 May 2020 at 22:39, Kurt Poulsen < kurt@...> wrote: Hi Leif If you are ready to invest a bit then look at and purchase one of these models. Then you have a first call SDR Radio and secondly by downloading the Spectrum Analyzer software on this link ? . On this page The SDR Uno software is also to download which is the software for SDR Radio application. The are several other SDR radio software which is supporting the various SDRPlay units. For a lower budget and get started above 50MHZ then anumber of low cost USB stick can be used and then visit the ? where there is a lot of information to study Look also under the supported software And for the USB dongles Good luck Kind regards Kurt ? ? Can you recommend one/a few which can do that? I have not found a SDR which could do that.
Leif ?
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I have one Airspy HF+ for HF and some VHF, one Softrock Ensemble
for HF,? one Airspy R0 for V-UHF and a dozen or so RTL-SDR digital
TV dongles repurposed for V-UHF receivers (very cheap, about $10).
As the software part (in fact the receiver, the mentioned
hardware are only front ends), I mostly use SDR# for all of them,
but I have other software such as SDR-Console, HDSDR, etc.
The bandwidths, demodulation modes and displays are all on the
software part.
Regards,
Ignacio, EB4APL
El 08/05/2020 a las 22:51, sala nimi
别蝉肠谤颈产颈ó:
Can you recommend one/a few which can do that? I have not found a
SDR which could do that.
Leif
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I concur: I have an RSP1A. I've used the "RSP Spectrum Analyzer" software (technically an FFT analyzer) with it on occasion ... it goes to 2GHz which is better than my ancient HP 8590A (nicknamed ole drifty).? I haven't used the optional DIY tracking generator yet.
Here is brief video on it:?
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Hmmm, now that I think about it a bit more, the tinysa and an SDR could make a very nice complementary pair. Paul WB1EMK?
On Fri, May 8, 2020, 3:06 PM EB4APL < eb4apl@...> wrote: Or use a SDR receiver as a poor man SA. You can see modulation sidebands
and splatter very well in the waterfall display. You can use really
small BWs.
Regards,
Ignacio EB4APL
El 08/05/2020 a las 8:08, erik@... 别蝉肠谤颈产颈ó:
> AS the minimum RBW is 2.7kHz you can not "See" you modulation
> For that you best use a receiver and a PC with line in.
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Below is the reason that I took interest in the tinysa. I had hoped to see and demonstrate how modulation works in the HF and VHF bands. The old SA that I have now can barely do that.?
Even if the tinysa was hooked to a computer to get the narrower band width that would be OK for me.?
Thanks for all the effort that you are doing on the project.
Joe
Joe Joncas WA7MHB Lincoln County Radio Amateur Club 541-272-3207
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How close to a carrier I can get? Many Hams, educators and me would like to see and check their modulators. That is, can I see what does spectrum of? SSB with 1kHz modulation look like. Or 300Hz and closer.
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The tinySA uses a downconverter, selectable band pass filters and signal strength measurement all in one integrated device. As a consequence the output of the band pass filters stay's inside the device.
It is possible to demodulate AM till at most 2kHz bandwidth and with a small trick it is possible to demodulate FM. But it is impossible demodulate SSB or look inside the spectrum of a 2.7kHz wide SSB transmission as the smallest bandwidth? of the tinySA resolution filters is equal to the complete 2.7kHz SSB. As there are so? many options to use (web) SDR receivers to look at the spectrum I assumed that would not be a big problem. But none of the cheap SDR's can do a spur free fast scan of 0.1 to 350MHz to study harmonics content.
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OK, very good to know. Thank you for the information.
Joe
Joe Joncas WA7MHB Lincoln County Radio Amateur Club 541-272-3207
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On May 9, 2020, at 9:44 AM, erik@... wrote:
The tinySA uses a downconverter, selectable band pass filters and signal strength measurement all in one integrated device. As a consequence the output of the band pass filters stay's inside the device.
It is possible to demodulate AM till at most 2kHz bandwidth and with a small trick it is possible to demodulate FM. But it is impossible demodulate SSB or look inside the spectrum of a 2.7kHz wide SSB transmission as the smallest bandwidth? of the tinySA resolution filters is equal to the complete 2.7kHz SSB. As there are so? many options to use (web) SDR receivers to look at the spectrum I assumed that would not be a big problem. But none of the cheap SDR's can do a spur free fast scan of 0.1 to 350MHz to study harmonics content.
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Thank you all. I have checked SDRs in the past and I thought that only a few or one could go very close to carrier.
Once again, thank you.
For your info, I have one SA from Aaronia Spectran something, but it wont go close enough. But it goes to 6GHz.
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Can you explain what you mean with "going close to the carrier"?
Can you give a practical example?
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On Mon, May 11, 2020 at 11:09 AM, <erik@...> wrote:
Can you explain what you mean with "going close to the carrier"?
Can you give a practical example?
========================================================== Erik, ? ?I believe he means that if your lowest resolution bandwidth is much wider than the modulation frequency then the modulation cannot be resolved in the presence of a nearby carrier.? The modulation gets integrated into the carrier.? I've "missed" many signals because they were too close to a carrier and I didn't use a narrow enough resolution bandwidth and slow enough sweep time to resolve them. ?-Herb
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I have been able to check side band suppression and carrier suppression by using a 2.5kHz tone as input. Of course this gives limited dynamic range but 40dB is possible for the opposite side band
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Kurt Poulsen
CT2FZI
Mat Breton