Date   

Re: DUO up/down band change

Neil Smith G4DBN
 

The values in the 1024-byte spectrum have a range of 50 to 255 decimal, so you can't get a value lower than 0x32 as part of the spectrum, so the spectrum control block header pattern and parameter control block headers cannot be sent as spectrum values.

The values in the VFO A/B are encoded as 8-byte pseudo-ascii, so can't have a 0x01 or 0xF3 for example.

To guard against sync loss, you read in the number of bytes specified in the header and if any of the ASCII values are out of range, bail out of decoding and look for a new header.

It's a while since I messed with interfacing, but it worked OK and seemed robust, but the test would be to cause some glitches and see if the decoder can recover.  If you read in a 1024 byte spectrum and byte 3 was 0x00 because of a long glitch, then so long as your parser can restart decoding at that point and doesn't have to discard the buffer, you would be able to recover gracefully.  Otherwise just ditch the lot and scan for another valid header frame.

Neil G4DBN


On 12/07/2020 16:48, Andy G4JNT wrote:

Having looked at the EXTIO protocol I'm now a bit confused.
There is an attempt to make a header for Spectrum and  Parameter data  ,   0x00 30 [30 30 34 30]   and  0x01 31 [3F 31 30 30] respectively, but as far as I can see it is not necessarily unique;   there is nothing to stop that series of bytes appearing in either the body of the spectrum data, which is just 8 bit byte values, or in some of the parameter fields.

I feel sure I've missed some point somewhere, as it clearly does work in practice with the Blue Duo etc,  but why doesn't framing go wrong ?

If the frame pattern is unique, then extracting just small amounts of parameter data is merely a case of looking for the frame, then counting bytes until the wanted ones arrive.   A small circular buffer a low as 31 bytes long would suffice for that - and any small processor like a PIC  could do it.



On Sat, 11 Jul 2020 at 08:24, Giovanni Franza <gfranza@...> wrote:

[Edited Message Follows]

Hi Andy,
the band of the spectrum is 192kHz and the bins are of 192/1024 kHz, because 192 kS/s is the sampling rate at which the internal SDR operates.
On the spectrum you can see the effect of the windowing as "shoulders" on the ending of the spectrum.
In BlueDUO I use and display only 160 kHz because I prefer not to show the part of band afflicted by the windowing.
Do not trust the spectrum timing. It is computed when the internal cpu has time, not on precise istants, even if the timings are more or less those.
Reards,

Giovanni - HB9EIK
_._,_._,


Re: DUO up/down band change

Andy G4JNT
 

Having looked at the EXTIO protocol I'm now a bit confused.
There is an attempt to make a header for Spectrum and  Parameter data  ,   0x00 30 [30 30 34 30]   and  0x01 31 [3F 31 30 30] respectively, but as far as I can see it is not necessarily unique;   there is nothing to stop that series of bytes appearing in either the body of the spectrum data, which is just 8 bit byte values, or in some of the parameter fields.

I feel sure I've missed some point somewhere, as it clearly does work in practice with the Blue Duo etc,  but why doesn't framing go wrong ?

If the frame pattern is unique, then extracting just small amounts of parameter data is merely a case of looking for the frame, then counting bytes until the wanted ones arrive.   A small circular buffer a low as 31 bytes long would suffice for that - and any small processor like a PIC  could do it.



On Sat, 11 Jul 2020 at 08:24, Giovanni Franza <gfranza@...> wrote:

[Edited Message Follows]

Hi Andy,
the band of the spectrum is 192kHz and the bins are of 192/1024 kHz, because 192 kS/s is the sampling rate at which the internal SDR operates.
On the spectrum you can see the effect of the windowing as "shoulders" on the ending of the spectrum.
In BlueDUO I use and display only 160 kHz because I prefer not to show the part of band afflicted by the windowing.
Do not trust the spectrum timing. It is computed when the internal cpu has time, not on precise istants, even if the timings are more or less those.
Reards,

Giovanni - HB9EIK


Re: Phase noise or front end overload #elad

Clint Chron
 

Hi Patrick,

 

If the problem signal was adjacent band, then external band pass filters will most likely help.  You need to know the source of the signal that was causing the problem.  If the signal was in-band, then a band pass filter will probably not help.

Did you see the “PK” light on the front of the Duo or the ADC Clip light on the SW-2 software?

 

At my home QTH, I get overload from the strong AM broadcast stations that are about 12 miles from my house.  I have an external AM band-stop filter on my Duo that gets rid of the overload.

 

73

Clint

W7KEC

 

From: EladSDR@groups.io [mailto:EladSDR@groups.io] On Behalf Of Patrick Bouldin KM5L
Sent: Sunday, July 12, 2020 7:33 AM
To: EladSDR@groups.io
Subject: [EladSDR] Phase noise or front end overload #elad

 

Greetings!

Hey I started out using the FDM DUO for Field day, almost all CW. Had to stop because with so much traffic something was creating a lot of phase noise, or just overload of some kind.

Have others experienced this? I don't have any of the external bandpass filters, maybe this will solve, what do you think?

73, 
Patrick KM5L


Phase noise or front end overload #elad

Patrick Bouldin KM5L <patrick@...>
 

Greetings!

Hey I started out using the FDM DUO for Field day, almost all CW. Had to stop because with so much traffic something was creating a lot of phase noise, or just overload of some kind.

Have others experienced this? I don't have any of the external bandpass filters, maybe this will solve, what do you think?

73, 
Patrick KM5L


Re: ART-120 Failure

Charles Ristorcelli
 

How did you open the fuse cap?

Did you use some type of sharp object to remove it?

Mine will not remove by just pulling or pressing it.

I am afraid of damaging it if I use a screwdriver or needle nose plioers.

--
73 de NN3V


Re: ART-60 Spectrum display #duo-art

Simon
 

Ah ok!!!!

Then u need an active loop antenna..lz1aq amp design is GOOD  

Use 4 square loops plus one set at 90 degrees to get 90 degree steering..and also a preferred homebrew noise canceller/ phaser..

I live in very built up london..s3-5 noise on active loop on 160..s5-7 on tx mag loop..

Simon 

On 11 Jul 2020, at 18:33, David KK7SS <d3j452@...> wrote:



Simon,
That's with the dummy load... just internally generated noise!
Quite noisy on my vertical - S6-S9 on 40M !
100ft from the main road intersection, street lights, power lines, traffic lights, etc.
Mercury and Sodium lights at the school 280 ft away!
And one of my neighbors has a plasma TV..
But it could be worse - I could be in an housing area with antenna bans  LOL

Dave KK7SS


Level Meter reading on alias products

Andy G4JNT
 

When using alias products on receive, ( eg at 144MHz), what does the level meter show when set to dBm ?

ie.  does it automatically take into account the SINC(X) loss



Noise from CAT input on revceive

Antony Watts
 

I have just connected up CAT & TX USB to my iMac, and am running Blackcat Systems SSTV app. Pictures are coming in fine on 14230kHz even among the wild SSB contest calls.

So I thought I would try to send something out too, so I configured the CAT for PTT to the USB port, and enabled RTS signalling. immediately the background "hiss' on receive rose by 1 S point. Why? Annoying.

Any ideas?


Re: ART-60 Spectrum display #duo-art

David KK7SS <d3j452@...>
 

Simon,
That's with the dummy load... just internally generated noise!
Quite noisy on my vertical - S6-S9 on 40M !
100ft from the main road intersection, street lights, power lines, traffic lights, etc.
Mercury and Sodium lights at the school 280 ft away!
And one of my neighbors has a plasma TV..
But it could be worse - I could be in an housing area with antenna bans  LOL

Dave KK7SS


Re: ART-60 Spectrum display #duo-art

Simon
 

-120 envious!!!


Re: ART-60 Spectrum display #duo-art

David KK7SS <d3j452@...>
 

Bob,
That helped a bit..
My DUO has a noise floor at about -120dBm
With my QTH and antenna I'm probably never going to get a signal above -30dBm.
I was trying to set those limits..
Had a stab at it this morning and gave up..
I can move the display up and down but can't seem to stretch it..
Such is life in the fast lane  Hi

73 de

Dave G.  KK7SS


Re: ART-60 Spectrum display #duo-art

Bob G3PJT <bob@...>
 

Yes it is a bit tricky but my notes say that 'Lev' sets the top line of the display.
Hope that helps
Bob G3PJT


Re: DUO up/down band change

Giovanni Franza
 
Edited

Hi Andy,
the band of the spectrum is 192kHz and the bins are of 192/1024 kHz, because 192 kS/s is the sampling rate at which the internal SDR operates.
On the spectrum you can see the effect of the windowing as "shoulders" on the ending of the spectrum.
In BlueDUO I use and display only 160 kHz because I prefer not to show the part of band afflicted by the windowing.
Do not trust the spectrum timing. It is computed when the internal cpu has time, not on precise istants, even if the timings are more or less those.
Reards,

Giovanni - HB9EIK


Re: DRM #fdm-sw2

Fred
 

Has there been any progress on the getting the new DRM decoder codecs to work .


ART-60 Spectrum display #duo-art

David KK7SS <d3j452@...>
 

My current Spectrum display range is from 0dBm to -110dBm.
Which parameter do I alter to get it to display -20dBm to -110dBm?
I can't seem to get it right !
Thanks..


Re: DUO up/down band change

Andy G4JNT
 

The FFT or spectrum Data:
1024 bytes sent every 150ms, can we assume approx 6Hz bins and 6kHz of spectrum ?
Or it is wider than that?



On Fri, 10 Jul 2020 at 22:00, Giovanni Franza <gfranza@...> wrote:
Hi Andy,
I confirm that the representation of the numeric values is not always the same, I think this depends from the fact that the protocol has been developed time to time, with different needs in mind.
Keeping in mind this, the documentation is good, and I left the code, even commented, to further help to implement.
Unfortunately the Arduino has not so much memory to compile the compete code and I was forced to comment out the part not essential for the goals of the sketch.
In BlueDUO sources (java - for Android Studio) it is possiible to see all the code uncommented, but I feel that Arduino sketch is simpler to read because it is most focused on the serial communication.
Have a nice day,

Giovanni - HB9EIK


Re: DUO up/down band change

Giovanni Franza
 

Hi Andy,
I confirm that the representation of the numeric values is not always the same, I think this depends from the fact that the protocol has been developed time to time, with different needs in mind.
Keeping in mind this, the documentation is good, and I left the code, even commented, to further help to implement.
Unfortunately the Arduino has not so much memory to compile the compete code and I was forced to comment out the part not essential for the goals of the sketch.
In BlueDUO sources (java - for Android Studio) it is possiible to see all the code uncommented, but I feel that Arduino sketch is simpler to read because it is most focused on the serial communication.
Have a nice day,

Giovanni - HB9EIK


Re: SW2/FDM-DUO CW Receive Sidetone

Charles Ristorcelli
 

Thanks.

I should have been more specific.

I am trying to adjust the tone sound.

Mine sounds like thunk-thunk. Absolutely horrible.
--
73 de NN3V


Re: DUO up/down band change

Giovanni Franza
 

Hi Antony,
this sketch was coded to help a friend OM that uses this controller to switch two audio filters during microwave contest.
The code was a sort of "reclicle" of BlueDUO code, that is free available on ELAD site.
Feel free to use as many code as you prefer, or to follow other ideas.
Have a nice day,

Giovanni


Re: DUO up/down band change

Andy G4JNT
 

THe coding is a bit confusing.
The control block, data length is sent LSB first  there's an underlined statement to say so !
  " 3°, 4°, 5° e 6° Length of the data following the control block (coded in ascii to facilitate synchronization) NB: this field is sent with the LSB first method. Hexadecimal value encoded in ascii. Example: for a length of 1024 bytes (0x0400 in hex), 0x30303430 is sent "

 
BUT  the VFO data is sent MSB first
"   The VFO is encoded in pseudo-ascii using its hexadecimal value. 
Example :  14.072.000Hz : 0x30 0x30 0x3D 0x36 0x3B 0x38 0x3C 0x30,  52.000.000Hz : 0x30 0x33 0x31 0x39 0x37 0x35 0x30 0x30"

It took a bit of playing around with a calculator to realise 14072000 = 0x0D6B8C0   and 52000000  = 0x03197500



On Fri, 10 Jul 2020 at 17:51, Giovanni Franza <gfranza@...> wrote:
To all,
AUX contains a pseudo serial, speed fixed at 115200 bps, that accept imperative CAT comands (no quesries) and send a continuous serial flow of data alternating FFT and radio status.
See this document: http://www.eladit.com/download/sdr/FDM-DUO/ELAD%20FDM-DUO%20-%20EXTIO%20Serial%20Protocol%20-%202017-09-08.pdf
I've developed a schetch that read that flow (but the Arduino has not enough memory to manage all the data): you can find at: http://www.eladit.com/download/sdr/Linux/sketch_2019_03_12.ino
Most of the code is commented out, but correct. The purpose is to activate/deactivate an output if the mode in SSB/CW. Also it has a pin to switch SSB/CW. It can be useful to inspect how the protocol works.
Also it can be modified to change bands and to display band and/or frequency used.
Hope this helps,

Giovanni - HB9EIK

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