Date   

Re: AirspyHF+ VHF performance in RF-dense environment

jdow
 

Si. It is.
{^_^}

On 20180218 12:26, Andrea IW0HDV wrote:
Off topic:
Is it _that_ Mount Wilson ?
(the one with Observatories  on top)
Andrea Montefusco IW0HDV
On Feb 18, 2018 19:14, "Chris Spacone" <cspacone@socal.rr.com <mailto:cspacone@socal.rr.com>> wrote:
I should go to Mount Wilson and try that!


Re: AirspyHF+ VHF performance in RF-dense environment

jdow
 

Try it close to some of the FM broadcast stations, too. You can damn near hold a fluorescent bulb up in the air and light it from the RF next to some of the towers.

{^_-} (Out towards KONT)

On 20180218 10:04, Chris Spacone wrote:
I should go to Mount Wilson and try that!
HF+ = remarkable.
-Chris
-----Original Message-----
From: main@airspy.groups.io [mailto:main@airspy.groups.io] On Behalf Of Dana Myers
Sent: Sunday, February 18, 2018 08:49
To: main@airspy.groups.io
Subject: [airspy] AirspyHF+ VHF performance in RF-dense environment
I took my R0 & HF+ (FW R1.3) up to major radio site yesterday (Mount Diablo in Northern California). I captured amateur packet APRS for several hours from the summit; this site has a very wide coverage area.
Not surprising, it is a popular commercial radio site, and I was parked within ~100m of a well-populated tower most of the time. While I do not know the exact mix of transmitters in the site these days, there are quite a VHF high-band transmitters and still some paging transmitters.
Most of the reception was at 144.39MHz.
My Airspy R0 was swamped until I turned the gain to ~6 in Linearity mode.
My AirspyHF+ didn't show any sign of the RF racket that I could discern.
Once again, that's a hot, strong VHF receiver!! Conventional amateur radios with wideband front-ends tend to overwhelm there; the HF+ behaved like a high-end land-mobile receiver.
Dana K6JQ


Re: AirspyHF+ VHF performance in RF-dense environment

Leif Asbrink
 

Hello Dana,

The HF+ will silently insert attenuation and degrade
NF in order to not become saturated by out-of-band
signals.

To really evaluate it you should evaluate S/N for
the stations of interest. Then, put attenuators in
front of your Airspy R0 until it is not swamped
(or adjust gain parameters if the range is adequate)
and evaluate S/N for the same stations. That would
be a fair comparison. Set the Airspy R0 for maximum
decimation to make the bandwidth of the tuner chip
minimum.

My guess is that you will find that the difference
between R0 and HF+ is not so big - but that the latest
HF+ firmware will allow a more favourable gain distribution.
Tweak the parameters in both cases - and if it does not
help, add an attenuator.

HF+ is a good radio - but the R0 is not bad.

The HF+ with its automagic AGC control is however easier to use...

73

Leif


I took my R0 & HF+ (FW R1.3) up to major radio site yesterday (Mount Diablo
in Northern California). I captured amateur packet APRS for several hours
from the summit; this site has a very wide coverage area.

Not surprising, it is a popular commercial radio site, and I was parked
within ~100m of a well-populated tower most of  the time. While I do not
know the exact mix of transmitters in the site these days, there are quite
a VHF high-band transmitters and still some paging transmitters.

Most of the reception was at 144.39MHz.

My Airspy R0 was swamped until I turned the gain to ~6 in Linearity
mode.

My AirspyHF+ didn't show any sign of the RF racket that I could discern.
Once again, that's a hot, strong VHF receiver!! Conventional amateur
radios with wideband front-ends tend to overwhelm there; the HF+ behaved
like a high-end land-mobile receiver.

Dana  K6JQ




Re: AirSpy HF R1.3/1644 Preamp on/off #airspyhfplus #firmware

Peter
 

Jaap De Goede wrote -

" So far I understood that the Spectrum Analyzer window is the result of a Fast Fourier Transformation of the HF tuner's digitized signal. I thought the AirSpy HF's HF Preamp would be either before or after the HF tuner. So the HF PreAmp status should affect the displayed level of the signal."

Ah well ... observation trumps expectation - hi !  (see https://airspy.com/downloads/HF+Architecture.png  )

One thing I have noted ... if the HF AGC is turned off, and some amount of manual HF ATT is applied, then that will persist in other applications using the HF+
eg : moving from SDR# to SDR Console, one will discover that the apparent HF+ signal level has dropped considerably !! ( by the amount of HF ATT applied )

It may be worthwhile bearing that in mind so as to protect user sanity   ;-)

Pete.


Re: AirspyHF+ VHF performance in RF-dense environment

Andrea IW0HDV
 

Off topic: 

Is it _that_ Mount Wilson ?

(the one with Observatories  on top)


Andrea Montefusco IW0HDV

On Feb 18, 2018 19:14, "Chris Spacone" <cspacone@...> wrote:
I should go to Mount Wilson and try that!


Re: AirSpyHF+ IW0HDV ExtIO: new release with HF manual controls #airspyhfplus

Ruben Navarro Huedo (EA5BZ)
 

thank's !


AirSpyHF+ IW0HDV ExtIO: new release with HF manual controls #airspyhfplus

Andrea IW0HDV
 

prog, all,

A first attempt to implement an ExtIO for new HF manual controls is found here:

https://github.com/IW0HDV/extio-iw0hdv/releases/tag/v1.0.6-2-g77e17c8


Re: #airspyhfplus #airspyhfplus

VE7KED
 

Sounds good.

So, at this point I am going to let this run for 5 days, at the end of which I will give some daily and  average stats with the current firmware.  I have added additional receivers into the mix.  Anyone interested in live monitoring of 20 meter performance can check the pskreporter website.  Receivers will be reporting as follows:

VA7PSK - HF+
VE7KED - IC-7610
VA7PKT - IC-9100
VA7EEE - SDRPlay RSP2Pro

Multicoupler is a Stridesberg MCA104M fed by a 20 meter dipole at about 24 feet ASL in the attic.

Mike


GQRX 2.9 Raspberry Pi #airspyhfplus #raspberrypi

Jaap De Goede <jaap.de.goede@...>
 

Hi,

GQRX 2.9 and Airspy HF+ work on Raspbian with the Raspberry Pi 3. Using the Rasbian November '17 image from the Rasberry Organization, you might face some issues:
  • GNURadio might not install after Raspbian update/ugrade: Install GNURadio on a clean image, before updating and upgrading Raspbian. 
  • AM demodulation has an issue with the sound system, there is a continuous overflow. Possibly using another sample rate for the audio sink could help, yet that cannot be configured.
  • To prevent overheating of the PI you could reduce the display rate of the waterfall.
Cheers, Jaap


Re: #airspyhfplus #airspyhfplus

Mike Millen
 

I, for one, find your testing of great interest, Mike.

If you're going to drop the daily reporting (no need, as far as I'm concerned) then please post a summary of your findings & opinions every few days or once a week at least.

Mike - M0MLM

On 18/02/2018 18:00, VE7KED wrote:
No the digi-sel is disabled.

You are right that band conditions and mixing of signals change for sure.  The purpose of this test is that my application is ft8 performance in the real world where this environment is where I spend all of my time.   The test is seeing how receievers hold up in this use situation.  I don't really care about how the receievr will work with a single signal in a prestine test environment where we can generate lab measurements.   I want to know how things are in an environment with 25 carriers mixing in close proximity to one another of varied signal strengths with a bit of human noise thrown into the mix for good measure.  There are settings and performance tweaks with the hardware and firmware which can make this excell or fail to some degree.  I'm sure we can all agree with this.

I'll spare the daily reporting since you guys are not seeing much value in this.  I though it may give some feedback on what changes happen when I update the firmware.  As each change made is not explicitly detailed to us, which I certainly don't expect and won't pretend I would understand in any meaningful way, I felt this might provide value to the developer who does know each little change made and what should be expected of same.


Re: AirspyHF+ VHF performance in RF-dense environment

Chris Spacone <cspacone@...>
 

I should bring one and document the results! Maybe next weekend.

-----Original Message-----
From: main@airspy.groups.io [mailto:main@airspy.groups.io] On Behalf Of Dana Myers
Sent: Sunday, February 18, 2018 10:16
To: main@airspy.groups.io
Subject: Re: [airspy] AirspyHF+ VHF performance in RF-dense environment

On 2/18/2018 10:04 AM, Chris Spacone wrote:
I should go to Mount Wilson and try that!
If I was still living down there, I would :-) Though Mt Wilson has places were florescent bulbs always glow from the RF :-)

HF+ = remarkable.
Absolutely.

73,
Dana K6JQ


Re: sdrsharp-catcontroller plugin

Ruben Navarro Huedo (EA5BZ)
 

ohhhh GOOD !!!!
You are "my man" Mariano ;-)


Re: AirspyHF+ VHF performance in RF-dense environment

Dana Myers
 

On 2/18/2018 10:04 AM, Chris Spacone wrote:
I should go to Mount Wilson and try that!
If I was still living down there, I would :-)  Though Mt Wilson
has places were florescent bulbs always glow from the RF :-)

HF+ = remarkable.
Absolutely.

73,
Dana  K6JQ


Re: #airspyhfplus #airspyhfplus

prog
 

On Sun, Feb 18, 2018 at 10:14 am, VE7KED wrote:
Since I don't know what the many other fixes are
In fact, the defaults changed a bit - but they can be changed in 1.3 anyway.


Re: #airspyhfplus #airspyhfplus

VE7KED
 

Thanks for the feedback.  If the ATT was the only change detailed in the firmware update foldee then yes this is where I would focus my attention. 

The reason I have changed nothing is that the firmware update says :

This revision adds the ATT setting to control the HF gain distribution. " Also, many other fixes. "

Since I don't know what the many other fixes are, I felt that needed to first test the new firmware with the same settings to see if these other fixes have resulted in any performance change before I start changing my HF+ receiver settings to test ATT features.

There's a pretty good chance I'm missing something here and am completely out to lunch with my approach so if you can give me other ideas on how I should do these steps I'm very open to other approaches.

Thanks again.

Mike


Re: AirspyHF+ VHF performance in RF-dense environment

Chris Spacone <cspacone@...>
 

I should go to Mount Wilson and try that!

HF+ = remarkable.

-Chris

-----Original Message-----
From: main@airspy.groups.io [mailto:main@airspy.groups.io] On Behalf Of Dana Myers
Sent: Sunday, February 18, 2018 08:49
To: main@airspy.groups.io
Subject: [airspy] AirspyHF+ VHF performance in RF-dense environment


I took my R0 & HF+ (FW R1.3) up to major radio site yesterday (Mount Diablo in Northern California). I captured amateur packet APRS for several hours from the summit; this site has a very wide coverage area.

Not surprising, it is a popular commercial radio site, and I was parked within ~100m of a well-populated tower most of the time. While I do not know the exact mix of transmitters in the site these days, there are quite a VHF high-band transmitters and still some paging transmitters.

Most of the reception was at 144.39MHz.

My Airspy R0 was swamped until I turned the gain to ~6 in Linearity mode.

My AirspyHF+ didn't show any sign of the RF racket that I could discern.
Once again, that's a hot, strong VHF receiver!! Conventional amateur radios with wideband front-ends tend to overwhelm there; the HF+ behaved like a high-end land-mobile receiver.

Dana K6JQ


Re: #airspyhfplus #airspyhfplus

VE7KED
 

No the digi-sel is disabled.

You are right that band conditions and mixing of signals change for sure.  The purpose of this test is that my application is ft8 performance in the real world where this environment is where I spend all of my time.   The test is seeing how receievers hold up in this use situation.  I don't really care about how the receievr will work with a single signal in a prestine test environment where we can generate lab measurements.   I want to know how things are in an environment with 25 carriers mixing in close proximity to one another of varied signal strengths with a bit of human noise thrown into the mix for good measure.  There are settings and performance tweaks with the hardware and firmware which can make this excell or fail to some degree.  I'm sure we can all agree with this.

By testing against a comparative receiver where no changes have been made, we start seeing how these firmware changes may be effecting our target receiver in this test environment.  Is it not a precision measurement, no but it is quantitative and gives a generalized view.

Now I do have two more recievers I can throw into the mix aswell at the same time as my multicoupler has 4 ports.  If they generally track each other's performance thereby accounting for prop and signal changes this is good.  Then if we change the firmware on one and see a drastic change in performance compared to what the others are doing, to me this is saying something about the changes made and how they impact my use environment.

Having done this for many months you get an idea of how things perform against one another when they are fed from the same antenna and can develop day over day statistics which can then be averaged with a certain level or accuracy.   The test results yesterday were very disproportionate toward the HF+ results of the day prior.   It was the best performance I have ever had from any receiver from my station not by a small fraction but but a huge margin.  My test yesterday was flawed due to audio level not being set correctly so I am testing again today.

I'll spare the daily reporting since you guys are not seeing much value in this.  I though it may give some feedback on what changes happen when I update the firmware.  As each change made is not explicitly detailed to us, which I certainly don't expect and won't pretend I would understand in any meaningful way, I felt this might provide value to the developer who does know each little change made and what should be expected of same.


Anyhow thanks again for the great feedback and support to the community guys.

Mike


Re: AirspyHF+ VHF performance in RF-dense environment

Dana Myers
 

On 2/18/2018 9:37 AM, Mike Tindor wrote:
Dana,

Just curious.    The HF+ is limited to 768 khz max whilst the R0 is limited to north of 8 mhz.    Were you using the HF+ at 768 khz or something lower?   And how about the R0?
I was interested in receiving a 20KHz NBFM channel, so I was using 48Ks/s
on the HF+ and 10Ms/s with decimation by 64 on the R0 (125Ks/s display).

Hope that helps,
Dana  K6JQ


Re: sdrsharp-catcontroller plugin

Mariano Sanchez Pont
 

It's almost finished! 
In about two or three days i'll have the OmniRig plugin working. At the moment it reads the frequencies of the two VFOs from the two transceivers.


Re: AirspyHF+ VHF performance in RF-dense environment

Mike Tindor
 

Dana,

Just curious.    The HF+ is limited to 768 khz max whilst the R0 is limited to north of 8 mhz.    Were you using the HF+ at 768 khz or something lower?   And how about the R0?

I'm just wondering what you had the R0 set at during the comparison (sample rate / decimation) and what you had the HF+ set at for bandwidth when tested.

Mike


On Sun, Feb 18, 2018 at 11:48 AM, Dana Myers <dana.myers@...> wrote:

I took my R0 & HF+ (FW R1.3) up to major radio site yesterday (Mount Diablo
in Northern California). I captured amateur packet APRS for several hours
from the summit; this site has a very wide coverage area.

Not surprising, it is a popular commercial radio site, and I was parked
within ~100m of a well-populated tower most of  the time. While I do not
know the exact mix of transmitters in the site these days, there are quite
a VHF high-band transmitters and still some paging transmitters.

Most of the reception was at 144.39MHz.

My Airspy R0 was swamped until I turned the gain to ~6 in Linearity
mode.

My AirspyHF+ didn't show any sign of the RF racket that I could discern.
Once again, that's a hot, strong VHF receiver!! Conventional amateur
radios with wideband front-ends tend to overwhelm there; the HF+ behaved
like a high-end land-mobile receiver.

Dana  K6JQ





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