Re: Initial Test of Main V12.6 board

John:

I would simply plug in the USB connector on the new Teensy, before you even solder pins on it, and run the ASCII Table example program. I use this program (Example-->Communications-->ASCIITable) because it also writes to the Serial object as part of its execution. If that's okay, at least you know you have a working Teensy and IDE. I would then hook up the Main board and the display and see if that works. If not, you should still be able to run the "Gauges" program that's in the RA8875 library (no hat necessary). If that fails, then something is wrong with the display or the Main board. Also, these simple tests don't use the front panel at all, so you don't have to contend with those, either.

Jack, W8TEE

On Sunday, May 4, 2025 at 07:26:10 AM EDT, John Owens K1JO via groups.io <johnowenschina@...> wrote:

Thanks Bill, I appreciate your help.
I've had a lot of years and experience building electronic gadgets but has really perplexed me.

I've been through 2 sets of Teensys, adapter boards, and audio hats, with the same results. They say the definition of crazy is to keep doing the same thing and expecting a different outcome, so though I have 2 more sets of teensys, boards, and audio hats. I don't want to a keep doing the same thing.
My next attempt? will be to test the teensy separately on a different I2C breadboard circuit.

Then if that is successful, I will dig into the audio hat documentation and see if I can breadboard a working circuit with it.?

Of course, I will try the one suggestion from you that I haven't tried yet, i.e. building and connecting the front panel board.?

Best regards,

John K1JO

--
Jack, W8TEE

Re: Initial Test of Main V12.6 board

#33762

Thanks Bill, I appreciate your help.
I've had a lot of years and experience building electronic gadgets but has really perplexed me.

I've been through 2 sets of Teensys, adapter boards, and audio hats, with the same results. They say the definition of crazy is to keep doing the same thing and expecting a different outcome, so though I have 2 more sets of teensys, boards, and audio hats. I don't want to a keep doing the same thing.
My next attempt? will be to test the teensy separately on a different I2C breadboard circuit.

Then if that is successful, I will dig into the audio hat documentation and see if I can breadboard a working circuit with it.?

Of course, I will try the one suggestion from you that I haven't tried yet, i.e. building and connecting the front panel board.?

Best regards,

John K1JO

Re: Codec & ADC's

#33761

The point is good that the half-voltage reference should not have noise applied.? But, for the audio range we work with, this is taken care of by proper capacitors.? It is an AC problem, so the VR noise can be filtered for any VR.

?

In my testing, I fed the analog supply with a 10 mH inductor, and several different bypass arrangements.? The bypass for Vref, that is brought out for both the SGTL5000 and the PCM1808, gets the recommended bypass treatment.? I believe the noise in the measurements is all associated with the ADC process.

?

Bob?? W7PUA

Re: t41 main board j22 connections

#33760

开云体育

Cool!

?

Dr. William J. Schmidt - K9HZ J62K(J68HZ) 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ VP2EHZ

?

Owner - Operator

Big Signal Ranch – K9ZC

Staunton, Illinois

?

Owner – Operator

Villa Grand Piton – 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@...

?

Show quoted text

From: [email protected] <[email protected]> On Behalf Of Tim O'Rourke via groups.io
Sent: Saturday, May 3, 2025 10:36 PM
To: [email protected]
Subject: Re: [SoftwareControlledHamRadio] t41 main board j22 connections

?

I can drop a handfull at your spot.

I will look up and post my spots also

Tim

Re: Codec & ADC's

#33759

开云体育

You probably know this but there have been several papers written on the weak signal performance of A/D and D/A converters being a function of the quality of the voltage reference quality.? Noise at the reference (the reference is generated internally with the PCM1808) that comes in via the Vcc power supply line sets the zero signal bit range of the device. ?That does beg the question of how clean the power is that was used in the experiment (to correlate to the zero “shorted” signal level).? I’ll have to try this myself to see because ‘ve been looking at some new low noise VRs for this very reason.

?

Dr. William J. Schmidt - K9HZ J62K(J68HZ) 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ VP2EHZ

?

Owner - Operator

Big Signal Ranch – K9ZC

Staunton, Illinois

?

Owner – Operator

Villa Grand Piton – 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@...

?

Show quoted text

From: [email protected] <[email protected]> On Behalf Of Bob Larkin
Sent: Saturday, May 3, 2025 5:40 PM
To: [email protected]
Subject: [SoftwareControlledHamRadio] Codec & ADC's

?

I recently did some ADC measurements in preparation for an update to my Audio VNA.? I mention it here as I think it has some stuff of interest to the T41 project.? The measurements are on-going, but as of now included the SGTL5000 (ADC side)and the PCM1808.? I believe it was the T41 use of the PCM1808 that got me to look at that part---thanks.? The web page for the study is

?

For this group, one interesting element that came out is that the PCM1808 produces 24-bit output data, but this is lost back to 16 if you input I2S via the Teensy AudioInputI2S followed by a Q15 to F32 conversion.? If you do the input via AudioInputI2S_F32 of the , it will include all 24-bits automatically, as well as saving a conversion.

?

?Questions, comments and corrections are all appreciated.? Bob? W7PUA

Re: t41 main board j22 connections

#33758

I can drop a handfull at your spot.

I will look up and post my spots also

Tim

Re: Codec & ADC's

#33757

Terrance, I believe you are correct, it is straightforward. ? The I16 version does the tough part and the I32 to F32 conversion works just like the 2-channel version. ? The trick is that I2S does not care how long the integer word is.? It just goes to the end and produces a (partially filled) 32 bit result. ? If you want to take a cut at it, please do.? Push it to the F32 library and I will try to get it right in.? Thanks much, Bob? W7PUA

Re: Initial Test of Main V12.6 board

#33756

开云体育

John… ??Two options.

?

If you programmed the teensy separated from the MAIN board and ran the teensy + hat off the just the USB cable powering the teensy thru the computer… and it doesn’t see the hat… either the hat is bad, or the hat is not making connection with the pins on the teensy, or the teensy is bad.?? That’s all there is.

?

If the teensy is now on the MAIN board, build the front panel board and cable it up to the main board.? see if it sees that.

?

Dr. William J. Schmidt - K9HZ J62K(J68HZ) 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ VP2EHZ

?

Owner - Operator

Big Signal Ranch – K9ZC

Staunton, Illinois

?

Owner – Operator

Villa Grand Piton – 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@...

?

Show quoted text

From: [email protected] <[email protected]> On Behalf Of John Owens K1JO via groups.io
Sent: Saturday, May 3, 2025 9:03 PM
To: [email protected]
Subject: Re: [SoftwareControlledHamRadio] Initial Test of Main V12.6 board

?

Still no I2C device found :(
I ohmed out all the connections between the stacked header pins through the Teensy and to the Teensy Audio adapter. I found some intermittent connection issues, which I think is due to the Tayda A-4662 male pin set for the Audio Hat. I noticed that Tayda sent me a substitute part, and I noticed that the pins were not as long a normal pins. So, I started over with a new Teensy 4.1, offset Audio adapter board and Teensy Audio board and longer header pins. I took lots of time to ensure that all solder joints were good and then used an ohm meter to check each pin from the stacked header pins to the Audio board. All were good.

I programmed the board with just the Teensy, adapter, and Audio board. Arudino IDE notice a? new board and port and did some automatic updates.?
The is started reporting no I2C device found. I'm not sure where to go from here...2 strikes.
I am using Arduino IDE version 2.3.6
Maybe I am missing a library??

Re: Initial Test of Main V12.6 board

#33755
Edited

Still no I2C device found :(
I ohmed out all the connections between the stacked header pins through the Teensy and to the Teensy Audio adapter. I found some intermittent connection issues, which I think is due to the Tayda A-4662 male pin set for the Audio Hat. I noticed that Tayda sent me a substitute part, and I noticed that the pins were not as long a normal pins. So, I started over with a new Teensy 4.1, offset Audio adapter board and Teensy Audio board and longer header pins. I took lots of time to ensure that all solder joints were good and then used an ohm meter to check each pin from the stacked header pins to the Audio board. All were good.

I programmed the board with just the Teensy, adapter, and Audio board. Arudino IDE notice a? new board and port and did some automatic updates.?
The is started reporting no I2C device found. I'm not sure where to go from here...2 strikes.
I am using Arduino IDE version 2.3.6
Maybe I am missing a library??

?

Scanning Wire ...

No I2C devices found

?

Scanning Wire 1 ...

No I2C devices found

Scanning Wire 2 ...
No I2C devices found

Re: t41 main board j22 connections

#33754

开云体育

Ok well I’ll be selling boards and kits in spot #2607 and I can put up a sign to direct them to your booth for those cables if you want…

?

Dr. William J. Schmidt - K9HZ J62K(J68HZ) 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ VP2EHZ

?

Owner - Operator

Big Signal Ranch – K9ZC

Staunton, Illinois

?

Owner – Operator

Villa Grand Piton – 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@...

?

Show quoted text

From: [email protected] <[email protected]> On Behalf Of Tim O'Rourke via groups.io
Sent: Saturday, May 3, 2025 7:59 PM
To: [email protected]
Subject: Re: [SoftwareControlledHamRadio] t41 main board j22 connections

?

Yes I will have 2 flea market spots in the new area, paved near where the EMC truck usually parks?

Tim

Re: Codec & ADC's

#33753

I've thought several times about creating a quad I2S object for the OpenAudio library.? At a glance it doesn't look that difficult.? Then I think if it was that easy, someone would have done it, so I put it off.

Re: t41 main board j22 connections

#33752

Yes I will have 2 flea market spots in the new area, paved near where the EMC truck usually parks?

Tim

Re: Codec & ADC's

#33751

Note that this 16 bit limitation of TeensyDuino is apparently why the dynamic range of the "software volume control" is limited.? 16 bits is enough, but you need to be able to output that into a 24 or 32 bit DAC with the 16 bits padded into 24 or 32 bit words.

The T41 is architecturally limited to the Teensy Duino I2S (quad I2S).? So the 16 bits get stuffed into 16 bit words, and when you get to lower volume levels, there is quantization noise.? At least that is the theory.

I've got it in my list of to-dos to hack a volume control into the receiver using the Open Audio library to see if it works better.

?

--

73 Greg KF5N

Re: t41 main board j22 connections

#33750

开云体育

You be at Hamvention?

?

Dr. William J. Schmidt - K9HZ J62K(J68HZ) 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ VP2EHZ

?

Owner - Operator

Big Signal Ranch – K9ZC

Staunton, Illinois

?

Owner – Operator

Villa Grand Piton – 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@...

?

Show quoted text

From: [email protected] <[email protected]> On Behalf Of Tim via groups.io
Sent: Saturday, May 3, 2025 6:49 PM
To: [email protected]
Subject: Re: [SoftwareControlledHamRadio] t41 main board j22 connections

?

If you need a nice clean jumper I have a lot of these.

anyone who wants one I will send on my nickel.

Tim?

Re: t41 main board j22 connections

#33749

If you need a nice clean jumper I have a lot of these.

anyone who wants one I will send on my nickel.

Tim?

Codec & ADC's

#33748

I recently did some ADC measurements in preparation for an update to my Audio VNA.? I mention it here as I think it has some stuff of interest to the T41 project.? The measurements are on-going, but as of now included the SGTL5000 (ADC side)and the PCM1808.? I believe it was the T41 use of the PCM1808 that got me to look at that part---thanks.? The web page for the study is

?

For this group, one interesting element that came out is that the PCM1808 produces 24-bit output data, but this is lost back to 16 if you input I2S via the Teensy AudioInputI2S followed by a Q15 to F32 conversion.? If you do the input via AudioInputI2S_F32 of the , it will include all 24-bits automatically, as well as saving a conversion.

?

?Questions, comments and corrections are all appreciated.? Bob? W7PUA

Re: Initial Test of Main V12.6 board

#33747

开云体育

It should be finding the hat at WIRE at 0x0A…

?

Its either not recognizing WIRE or its shorted somewhere.

?

You can remove the teensy and hat off (as one unit)… jump the voltage tab that you cut in the instructions (UNTIL YOU REINSTALL THE TEENSY BACK ON THE MAIN BOARD), plug in the USB cable as if you were programming the Teensy, but rather to supply power and see if 0x0A shows up.? If not you have it located in a connection between the hat and the Teensy.

?

You can also just build a small section of one of the other boards that includes the I2C stuff… cable it to the MAIN board and see if it sees it.? The logical choice is the Front Panel… and you just need to install the IC’s, connectors, and the jumpers on the electronics board of it…not the switches to see if it at least can read that board.

?

Dr. William J. Schmidt - K9HZ J62K(J68HZ) 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ VP2EHZ

?

Owner - Operator

Big Signal Ranch – K9ZC

Staunton, Illinois

?

Owner – Operator

Villa Grand Piton – 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@...

?

Show quoted text

From: [email protected] <[email protected]> On Behalf Of John Owens K1JO via groups.io
Sent: Saturday, May 3, 2025 2:32 PM
To: [email protected]
Subject: Re: [SoftwareControlledHamRadio] Initial Test of Main V12.6 board

?

It is still reporting No I2C devices found :(
Any advice?

Re: Initial Test of Main V12.6 board

#33746

It is still reporting No I2C devices found :(
Any advice?

Re: Initial Test of Main V12.6 board

#33745

Thanks Bill. Good idea Oliver.

Re: t41 main board j22 connections

#33744

Right behind you 78!