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Re: V12 compiling error

 

With smallest LTO
emory Usage on Teensy 4.1:
? FLASH: code:206376, data:127280, headers:8356 ? free for files:7784452
? ?RAM1: variables:178560, code:195720, padding:888 ? free for local variables:149120
? ?RAM2: variables:474752 ?free for malloc/new:49536
Re: V12 compiling error

 

That's the right file. Did you optimize for smallest code with LTO? And you are using IDE 2.4.3?

Jack, W8TEE

On Monday, February 10, 2025 at 04:21:18 PM EST, Tim via groups.io <w4yn@...> wrote:


I got the beta V063-1-2 running and staying up now, not sure what I did different.
My PB's are not what they were before Probably need different menu file?
I noticed that Calibrate RX is way wonky doesn't look at all correct.
But it is running I moved fan around maybe that helped I don't have back on case fan is just positioned near Tweensy?
Temp says 42 degrees C
Tim?

--
Jack, W8TEE
Re: Initial RX calibration not working

 

Apparently I've missed the write-up on the V12 receive calibration that Tim is referring to.
Any chance that someone can point me to where I can find it as well as the latest software
version that he is using.? I haven't been able to keep up with all the changes and I admit
to getting confused (old age??) when messages refer to software or other documentation
without a specific reference.
?
Thanks so much!
Steve
K8ZBE
Re: Rob Sherwood Presentation Slides on Amateur Radio Transceiver Performance

 

Yes Pure Signal is open. Go take a look at Thetis for the Anan or Hermes/Hermes Lite radio.
?
My simplistic thinking is that it works a bit like noise cancelling headphones, except the thing cancelled is the noise (distortion) added to the signal by the Tx chain not the external noise.
?
Delay in the Tx chain exists but I don't think that stops the predistortion from cancelling IMD. The IMD created in the chain for a given input to the chain should be deterministic and repeatable.
?
On Mon, Feb 10, 2025 at 03:33 PM, Greg KF5N wrote:

You can do negative feedback.? But there has to be a phase adjustment so the system is stable.
?
I thought the "Pure Signal" pre-distortion software was open source?
?
--
73 Greg KF5N
Re: Rob Sherwood Presentation Slides on Amateur Radio Transceiver Performance

 

There is a short introduction to predistortion in Experimental Methods in RF Design Section 10.? But, you do need to apply predistortion in both amplitude and phase.? DSP is the way to that.
?
And feedback works, as Greg says.? Imagine an I-Q receiver on an attenuated? output of the transmitter.? This should look just like the delayed input (but doesn't because of distortion), after scaling. Negative feedback can then be applied at the baseband level.
?
Various negative feedback schemes have been applied at RF, but this is tough to do over multi stages, because of the phase shifts.
?
My favorite is feed-forward (search on that along with RF amplifier).? In that case, you take an attenuated sample of the main RF amplifier and subtract that from a delayed sample of the input.? That is the error waveform.? Amplify that error and subtract it from the delayed main amplifier output.? Presto, most of the distortion is gone.? The main amplifier input can include a weak pilot signal that is used to slowly adjust the gains and phases.? All you do is adjust everything to remove the pilot signal at the final output. ? I designed one of these for 900 MHz, a long time ago, and it worked well. A fair number of feed-forward amplifiers are? out there.? Generally they are quite a bit better than the predistorters.? They can be built without DSP, but they do need slow processing.
?
In any event, Jerry is right, there are indeed more efficient methods than class A.
?
73, Bob? W7PUA
Re: V12 compiling error

 

Says STDVer64.ino
But screen says 63-1-2
tim
Re: V12 compiling error

 

Zip you sent says 64 but the display on screen says 63-1-2?
I will try again
Tim?
Re: [AmateurRadioBuilders] [SoftwareControlledHamRadio] Rob Sherwood Presentation Slides on Amateur Radio Transceiver Performance

 

¿ªÔÆÌåÓý

The new attenuator/ 20W dummy load I made can be used as just a 40db tap on the RF line for feedback for something like this (besides the radio calibration).? I don¡¯t think it¡¯s that difficult to design a filter that notches out the salient part of the RF spectrum and add the inverse of the garbage back to the signal at the correct amplitude and phase to cancel the garbage out.? I¡¯ve worked on problems like this before¡­ if I get time to do it¡­ I¡¯ll have a look.

?

?

Dr. William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ VP2EHZ

?

Owner - Operator

Big Signal Ranch ¨C K9ZC

Staunton, Illinois

?

Owner ¨C Operator

Villa Grand Piton ¨C J68HZ

Soufriere, St. Lucia W.I.

Rent it:

?

Moderator: North American QRO Group at Groups.IO.

Moderator: Amateur Radio Builders Group at Groups.IO.

?

email:? bill@...

?

?

From: [email protected] <[email protected]> On Behalf Of jerry-KF6VB
Sent: Monday, February 10, 2025 2:25 PM
To: [email protected]
Cc: [email protected]
Subject: Re: [AmateurRadioBuilders] [SoftwareControlledHamRadio] Rob Sherwood Presentation Slides on Amateur Radio Transceiver Performance

?

On 2025-02-10 11:34, K9HZ wrote:
In any

case, he does tout using class-A final RF amplifiers in the transmit
stages of radios because they, by shear design, will generate less
IMD.

*** NO thanks. A 100W transmitter the size of a Heathkit Apache?
Or a legal-limit rig the size of a Piper Apache?

Predistortion is interesting. Right now, all implementations that I
know of are closely held commercial secrets. Anybody know of an
open-source attempt to do it?

It doesn't seem THAT complicated. Basically, the power amp's gain
gets a
little lower as it approaches its amplitude limit. So you compensate
for that
by raising the gain a little - only for the tips of the low-level RF.
You
"exaggerate the tips" a little. Sort of a negative feedback situation.

But what about actual negative feedback? Won't work, because there's
too much
delay in the RF chain. Guaranteed, at some frequency or frequencies, it
would ring
like a bird.

Yet, the commercial systems apparently *do* feed RF back into the
exciter. Do they
"SSB-detect" it, turn it back into audio, and compare that to the audio
being input?

- Jerry, KF6VB

Re: V12 compiling error

 

What I sent you was STDVer064. You're compiling someone else's code.


On Monday, February 10, 2025 at 04:21:18 PM EST, Tim via groups.io <w4yn@...> wrote:


I got the beta V063-1-2 running and staying up now, not sure what I did different.
My PB's are not what they were before Probably need different menu file?
I noticed that Calibrate RX is way wonky doesn't look at all correct.
But it is running I moved fan around maybe that helped I don't have back on case fan is just positioned near Tweensy?
Temp says 42 degrees C
Tim?

--
Jack, W8TEE
Re: V12 compiling error

 

This code is 100K larger than mine. Where did this code come from and do you have the compile flags set properly (e.g., smallest code size with LT)?

Jack, W8TEE

On Monday, February 10, 2025 at 04:26:48 PM EST, Tim via groups.io <w4yn@...> wrote:


IDE 2.3.4
Latest compile
? FLASH: code:303292, data:130360, headers:8708 ? free for files:7684104
? ?RAM1: variables:182112, code:279560, padding:15352 ? free for local variables:47264
? ?RAM2: variables:474720 ?free for malloc/new:49568
?

--
Jack, W8TEE
Re: V12 compiling error

 

IDE 2.3.4
Latest compile
? FLASH: code:303292, data:130360, headers:8708 ? free for files:7684104
? ?RAM1: variables:182112, code:279560, padding:15352 ? free for local variables:47264
? ?RAM2: variables:474720 ?free for malloc/new:49568
?
Re: V12 compiling error

 

I got the beta V063-1-2 running and staying up now, not sure what I did different.
My PB's are not what they were before Probably need different menu file?
I noticed that Calibrate RX is way wonky doesn't look at all correct.
But it is running I moved fan around maybe that helped I don't have back on case fan is just positioned near Tweensy?
Temp says 42 degrees C
Tim?
Re: V12 compiling error

 

This is what I get:

Inline image

This is for the new code we will be releasing within a week.

Tim: What version of the IDE are you using and do you have the compile options set?


Jack, W8TEE

On Monday, February 10, 2025 at 03:33:19 PM EST, jerry-KF6VB <jerry@...> wrote:


Tim,

? ? Here's a binary.? You should be able to load it into your radio.
It's not perfect, but it does basically work.

? ? ? ? ? ? ? ? ? ? ? - Jerry, KF6VB



On 2025-02-10 12:25, Tim via groups.io wrote:
> Memory Usage on Teensy 4.1:
>? FLASH: code:303292, data:130360, headers:8708? free for
> files:7684104
>? ? RAM1: variables:182112, code:279560, padding:15352? free for local
> variables:47264
>? ? RAM2: variables:474720? free for malloc/new:49568
>
> Ran longer but still shut down.
> TIM
>
>
> Links:
> ------
> [1] /g/SoftwareControlledHamRadio/message/32698
> [2] /mt/111092895/243852
> [3] /g/SoftwareControlledHamRadio/post
> [4] /g/SoftwareControlledHamRadio/editsub/243852
> [5]
> /g/SoftwareControlledHamRadio/leave/10484476/243852/1943518115/xyzzy






--
Jack, W8TEE
Re: V12 compiling error

 

Tim,

Here's a binary. You should be able to load it into your radio.
It's not perfect, but it does basically work.

- Jerry, KF6VB

On 2025-02-10 12:25, Tim via groups.io wrote:
Memory Usage on Teensy 4.1:
FLASH: code:303292, data:130360, headers:8708 free for
files:7684104
RAM1: variables:182112, code:279560, padding:15352 free for local
variables:47264
RAM2: variables:474720 free for malloc/new:49568
Ran longer but still shut down.
TIM
Links:
------
[1] /g/SoftwareControlledHamRadio/message/32698
[2] /mt/111092895/243852
[3] /g/SoftwareControlledHamRadio/post
[4] /g/SoftwareControlledHamRadio/editsub/243852
[5]
/g/SoftwareControlledHamRadio/leave/10484476/243852/1943518115/xyzzy

SDTVer063-1-beta.ino.hex
SDTVer063-1-beta.ino.hex

Re: Rob Sherwood Presentation Slides on Amateur Radio Transceiver Performance

 

You can do negative feedback.? But there has to be a phase adjustment so the system is stable.
?
I thought the "Pure Signal" pre-distortion software was open source?
?
--
73 Greg KF5N
Re: V12 compiling error

 

Memory Usage on Teensy 4.1:
? FLASH: code:303292, data:130360, headers:8708 ? free for files:7684104
? ?RAM1: variables:182112, code:279560, padding:15352 ? free for local variables:47264
? ?RAM2: variables:474720 ?free for malloc/new:49568
?
Ran longer but still shut down.
TIM
Re: Rob Sherwood Presentation Slides on Amateur Radio Transceiver Performance

 

On 2025-02-10 11:34, K9HZ wrote:
In any
case, he does tout using class-A final RF amplifiers in the transmit
stages of radios because they, by shear design, will generate less
IMD.
*** NO thanks. A 100W transmitter the size of a Heathkit Apache?
Or a legal-limit rig the size of a Piper Apache?

Predistortion is interesting. Right now, all implementations that I
know of are closely held commercial secrets. Anybody know of an
open-source attempt to do it?

It doesn't seem THAT complicated. Basically, the power amp's gain gets a
little lower as it approaches its amplitude limit. So you compensate for that
by raising the gain a little - only for the tips of the low-level RF. You
"exaggerate the tips" a little. Sort of a negative feedback situation.

But what about actual negative feedback? Won't work, because there's too much
delay in the RF chain. Guaranteed, at some frequency or frequencies, it would ring
like a bird.

Yet, the commercial systems apparently *do* feed RF back into the exciter. Do they
"SSB-detect" it, turn it back into audio, and compare that to the audio being input?

- Jerry, KF6VB
Re: V12 compiling error

 

Did you see my email on this?

Jack, W8TEE


For reason I can't explain, the IDE hides some libraries in the folder you defined in your Preferences section, which you can find at the File-->Preferences menu:

Inline image


As you can see, my projects go the C:\BookT41Rel4\Software. In that folder, you will find a subfolder named Libraries. The timer.h file is found there. If you have not defined a project folder in Preferences, I'm not sure where the file is placed and you will likely get the file not found error message.

Jack, W8TEE



--
Jack, W8TEE
Re: V12 compiling error

 

¿ªÔÆÌåÓý

Search ¡°TIMER¡± by Steffan Staub in the library search and install it.? Should be rev 1.2.1

?

?

Dr. William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ VP2EHZ

?

Owner - Operator

Big Signal Ranch ¨C K9ZC

Staunton, Illinois

?

Owner ¨C Operator

Villa Grand Piton ¨C J68HZ

Soufriere, St. Lucia W.I.

Rent it:

?

Moderator: North American QRO Group at Groups.IO.

Moderator: Amateur Radio Builders Group at Groups.IO.

?

email:? bill@...

?

?

From: [email protected] <[email protected]> On Behalf Of Tim via groups.io
Sent: Monday, February 10, 2025 1:36 PM
To: [email protected]
Subject: Re: [SoftwareControlledHamRadio] V12 compiling error

?

I didn't find that on his github but maybe I was was on wrong thread

Only file I seem to be missing now is the timer.h?

Not sure what library that is in.?

It was not used in 50.2 as far as I can tell.

Tim?
Re: V12 compiling error

 

I didn't find that on his github but maybe I was was on wrong thread
Only file I seem to be missing now is the timer.h?
Not sure what library that is in.?
It was not used in 50.2 as far as I can tell.
Tim?
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