Date   
Re: #qcx Firmware version 1.02 release #qcx

Joe Street
 

Hang on a second,  doesn't it go without saying that if I prefer a different tone for CW that I should change the filter constants for the CW filter during the build and change the LO offset also?  If people are simply modifying the audio tone of the sidetone, then how are they zero beating the station they want to work?

Joe ve3vxo


On Mon, Nov 11, 2019 at 12:38 AM Hans Summers <hans.summers@...> wrote:
Hi Tom:

> I find that the sidetone issue in T102a occurs when the keyer menu is set for 
> straight key, but the issue does not occur not when set for an iambic paddle.  
> That's kind of curious.

Many thanks for this observation. I investigated and determined that the problem occurs because in straight key mode, the key state is continuously checked and actioned; in paddle modes, once key-down has started there is no further change to the TX state (and sidetone) until a defined period later e.g. 0.1 seconds for a 12wpm "dit". The continuous updates in straight key mode were resetting my new sidetone generation system. 

Easily fixed, just one line of code... now straight key sidetone is perfect too! 1.02b coming shortly. 

Hi Chopper:

> T1.02a loaded and working fine with the exception that as mentioned above 
> sidetone freq becomes distorted below 750  and as you get down to 500 or 600 
> the tone disappears and is simply key clicks.  Not a major issue but a change as 
> 1.01 had working tone at 500.  If you are having issues with side tone simply 
> increase it to 750.

I investigated this too and did not completely agree with your findings. From what I saw (or rather, heard) here the sidetone is working perfectly fine as your lower its frequency. However, it gets very quiet. You are left with whatever residual clicks exist (from Tx/Rx switching etc) that are unrelated to sidetone. But they are prominent because the sidetone volume is low. 

The low sidetone volume is due to two factors:

1) At low sidetone frequency, the timer period that generates the Pulse Width Modulation (PWM) is corresponding longer. The fixed amount (depending on volume setting) that is added/subtracted for the sidetone waveform generation is therefore proportionately smaller than it is at 700Hz; which results in a lower volume. 

2) The sidetone generation method is now much cleaner and more elegant than the previous system. Rather than a very short pulse whose harmonics are being filtered out, we now have effectively a proper 50% duty cycle squarewave at the chosen sidetone frequency. I think the CW filter does a much better job at filtering this, with the result that the attenuation is higher; remember at 500Hz the skirts of the CW filter mean already 15-20dB attenuation. 

By the way for fun I set the sidetone frequency to 350Hz, and I could just about barely hear the 2nd harmonic at 700Hz coming through the filter; this is satisfying because it is a very low level as one would expect for a nice clean squarewave (50% duty cycle). 

I could solve 1) by automatically adjusting the PWM frequency (which is 42kHz for 700Hz) so that the multiplier is higher at low sidetone frequencies, and 42kHz would be maintained; I'm a bit reluctant to fiddle with that in case it breaks something else ;-)   I could also have solved it by automatically increasing the size of the sidetone frequency PWM steps but, since the timer holds integers and the values are already fairly small, that would get complicated since I wouldn't be able to put fractional values in. 

Therefore just to keep everything very simple and not risk breaking anything (after all, most people just leave sidetone frequency at the default 700Hz), the simple solution I came up with is just increase the number of digits of the sidetone volume to 3 (the default volume is still 99, now displayed 099). This gives the operator more flexibility to increase the sidetone volume if lower sidetone frequencies are preferred and the volume is found to be too quiet. 

The maximum volume value that makes any sense is 0.5 * 20,000,000 / (60 * sideToneFreq) otherwise the width of the PWM for the sidetone frequency generation would exceed the timer period. So for example:
  • 700Hz sidetone: max volume 238
  • 600Hz sidetone: max volume 277
  • 500Hz sidetone: max volume 333
  • 400Hz sidetone: max volume 416
But don't worry, if you set a volume level higher than the "maximum" then the system automatically limits it according to the formula. 

Hi Guido:

> This older display seems to requires at least 60us delay after the
> first nibble write, and also require RS to be HIGH for an extended
> period of time. The newer display is not sensitive to this at all..

:-O   All the QRP Labs kits forever have never had those timings... there is no 60us delay after the first nibble write (before the next nibble write). Neither is RS high for an extended period of time. The only change I made to fix the problem with some of the displays is that I extended the pulse width of the LCD_E signal by 2 CPU cycles (100 nanoseconds). So to toggle the LCD_E signal the port pin is set high, then wait 2 CPU cycles, then set it low again. This puts the LCD_E signal back to the former behaviour, which is also the same as used on all other QRP Labs kits (Ultimate3S, VFO, Clock). 

Version 1.02b will be coming shortly... I just want to check the other feedback received in other threads and emails... 

73 Hans G0UPL

Re: 40 Meter QCX overvoltage failure - likely dead chips - repair possible?

Nick Austen
 

Many thanks Gregg - I will take a look and see if I can manage it.

I will also source these two chips somewhere online.

Best regards 
Nick

On Mon, 11 Nov 2019 at 9:12 pm, Gregg Myers <gregg.w7grm@...> wrote:
Hi Nick,

Well, sorry to hear about the 'Si5351A error' message. Regarding replacing the SMD chip, I have recently been watching YouTube videos on thIs stuff called ChipQuik, which is basically a low temperature metal alloy (probably bismuth) to get SMD devices off without using a hot air station.  See here: 

But I haven’t tried using this stuff myself! There are a few manufactures selling similar alloys. Coincidentally, I ordered some yesterday from Amazon to try out. Anyway, it looks easy, but not having tried it myself, I can’t say for sure!

73,
Gregg W7GRM

On Mon, Nov 11, 2019 at 6:00 AM <n.j.austen@...> wrote:
Hi,
I am trying to repair my QCX 40m after a stray cut-resistor-leg appeared to have shorted 5v to 12v.
I have now managed to flash a new T1.02a ATmega328 - and got past the "Use original IC" thanks to help from Hans.

Now I have got (after a successful sign-on message): "Si5351A error" - which I was fearing. Maybe the FST3253 will be next?

Q1: Has anyone successfully repaired a QCX after such and over voltage? If so, what was the list of components needing replacement?
Q2: Is there any simple/reasonable way to replace the surface mount devices (including the Si5351A)? :)
Q3: Is it worth trying?

Many thanks,
Nick.

Re: 40 Meter QCX overvoltage failure - likely dead chips - repair possible?

Gregg Myers
 

Hi Nick,

Well, sorry to hear about the 'Si5351A error' message. Regarding replacing the SMD chip, I have recently been watching YouTube videos on thIs stuff called ChipQuik, which is basically a low temperature metal alloy (probably bismuth) to get SMD devices off without using a hot air station.  See here: 

But I haven’t tried using this stuff myself! There are a few manufactures selling similar alloys. Coincidentally, I ordered some yesterday from Amazon to try out. Anyway, it looks easy, but not having tried it myself, I can’t say for sure!

73,
Gregg W7GRM

On Mon, Nov 11, 2019 at 6:00 AM <n.j.austen@...> wrote:
Hi,
I am trying to repair my QCX 40m after a stray cut-resistor-leg appeared to have shorted 5v to 12v.
I have now managed to flash a new T1.02a ATmega328 - and got past the "Use original IC" thanks to help from Hans.

Now I have got (after a successful sign-on message): "Si5351A error" - which I was fearing. Maybe the FST3253 will be next?

Q1: Has anyone successfully repaired a QCX after such and over voltage? If so, what was the list of components needing replacement?
Q2: Is there any simple/reasonable way to replace the surface mount devices (including the Si5351A)? :)
Q3: Is it worth trying?

Many thanks,
Nick.

40 Meter QCX overvoltage failure - likely dead chips - repair possible?

Nick Austen
 

Hi,
I am trying to repair my QCX 40m after a stray cut-resistor-leg appeared to have shorted 5v to 12v.
I have now managed to flash a new T1.02a ATmega328 - and got past the "Use original IC" thanks to help from Hans.

Now I have got (after a successful sign-on message): "Si5351A error" - which I was fearing. Maybe the FST3253 will be next?

Q1: Has anyone successfully repaired a QCX after such and over voltage? If so, what was the list of components needing replacement?
Q2: Is there any simple/reasonable way to replace the surface mount devices (including the Si5351A)? :)
Q3: Is it worth trying?

Many thanks,
Nick.

Re: More paddles and keys ...

David Wilcox
 

QSL

David J. Wilcox K8WPE’s iPad

On Nov 11, 2019, at 6:47 AM, Ken KM4NFQ <km4nfq@...> wrote:


Thanks for you kind words David, K8WPE.
I started work on the DIY Dual Lever Paddle by drawing a couple of diagrams.

<paddles01.png>
<paddles02.png>
These were used as a guide to get started.
This is a snapshot of a piece of scrap brass used to make some parts.

<castbrass.png>

I used a reciprocating cut saw to cut out the block, and a micro-lathe to machine it in a 4-jaw chuck.
The micro-lathe has a three inch swing.
The 8-32 brass screws, nuts, and knurled nuts were bought at the local Ace hardware store.

Regards,
Ken, KM4NFQ "Not Fully Qualified"
https://github.com/muurtikaar/mega-morse-tutor

Regards,
Ken, KM4NFQ "Not Fully Qualified"
https://github.com/muurtikaar/mega-morse-tutor


On Mon, Nov 11, 2019 at 5:33 AM David Wilcox via Groups.Io <Djwilcox01=yahoo.com@groups.io> wrote:
Beautiful.  Not “pretty” yet but made with your own hands.  I am sure your CW will be a joy to hear.  It has heart and soul...... 

David J. Wilcox K8WPE’s iPad

On Nov 10, 2019, at 5:27 PM, Ken KM4NFQ <km4nfq@...> wrote:


Greetings,

I have been working on a DIY Dual Lever Paddle made from brass & steel.
Here are a couple of work-in-progress snapshots:

<paddle001.png>
<paddle002.png>

I still need to bevel the sharp corners, and clean it up.
I had the steel and the brass in the shop, as well as the sterling silver for the contact points.
The springs are from the battery compartment of an old toy.
The main expenses were for brass screws, nuts, knurled nuts, and taps/drills.
I estimate that I have about $40.00 + time & labor invested in this paddle.
I have had fun making it.

Regards,
Ken, KM4NFQ "Not Fully Qualified"
https://github.com/muurtikaar/mega-morse-tutor

Re: Programming blank ATmega328P with QCX frimware

Don--AE4DW
 

This thread definitely confirms why, I'm guessing, so many people just buy the pre-programmed chip from Hans and call it a day.

I'm not a qcx owner, just a U3S and clock owner. I'm reasonably skilled with this kind of stuff, but definitely not a hardware expert nor a software developer. When the clock firmware update was released, I used an arduino board as a "holder" for the existing clock chip, and updated with my USBTiny. Smooth as silk.

But as it relates to the whole bootloader discussion, my experience suggests to me a blank chip can be flashed just fine..I did so for a friend who had a problem with his clock that turned out to be a bad avr chip (no idea what caused it to fail). Blank 328P in arduino board, USBTiny, AVR Dudess, check and double-check fuses, and the firmware loaded with no issues.

 

Re: Is my QCX 30 a write-off?

Alan G4ZFQ
 

The thing that stands out is pin 27, check again, maybe it's a typo?
IC2 -27    0    SDA/LCD RS ?5V?
In another thread it seems confirmed that pin 27 is pulsed briefly, the manual is wrong.
https://groups.io/g/QRPLabs/message/39822
So I'm at a loss as to what to suggest.

73 Alan G4ZFQ

Re: More paddles and keys ...

Ken KM4NFQ
 

Thanks for you kind words David, K8WPE.
I started work on the DIY Dual Lever Paddle by drawing a couple of diagrams.

These were used as a guide to get started.
This is a snapshot of a piece of scrap brass used to make some parts.


I used a reciprocating cut saw to cut out the block, and a micro-lathe to machine it in a 4-jaw chuck.
The micro-lathe has a three inch swing.
The 8-32 brass screws, nuts, and knurled nuts were bought at the local Ace hardware store.

Regards,
Ken, KM4NFQ "Not Fully Qualified"
https://github.com/muurtikaar/mega-morse-tutor

Regards,
Ken, KM4NFQ "Not Fully Qualified"
https://github.com/muurtikaar/mega-morse-tutor


On Mon, Nov 11, 2019 at 5:33 AM David Wilcox via Groups.Io <Djwilcox01=yahoo.com@groups.io> wrote:
Beautiful.  Not “pretty” yet but made with your own hands.  I am sure your CW will be a joy to hear.  It has heart and soul...... 

David J. Wilcox K8WPE’s iPad

On Nov 10, 2019, at 5:27 PM, Ken KM4NFQ <km4nfq@...> wrote:


Greetings,

I have been working on a DIY Dual Lever Paddle made from brass & steel.
Here are a couple of work-in-progress snapshots:

<paddle001.png>
<paddle002.png>

I still need to bevel the sharp corners, and clean it up.
I had the steel and the brass in the shop, as well as the sterling silver for the contact points.
The springs are from the battery compartment of an old toy.
The main expenses were for brass screws, nuts, knurled nuts, and taps/drills.
I estimate that I have about $40.00 + time & labor invested in this paddle.
I have had fun making it.

Regards,
Ken, KM4NFQ "Not Fully Qualified"
https://github.com/muurtikaar/mega-morse-tutor

Re: #qcx Firmware version 1.02 release #qcx

Guido PE1NNZ
 

Hi Hans,

The 1.02b firmware is working fine with the problematic LCD display.

For you interest, the 60us delay on the problematic display seems to be necessary for the next consecutive character write (and done anywhere in the code), and yes LCD_EN needs to be at least 100ns active. RS pulse is given just after LCD_EN is high and low after LCD_EN got low, for the first nibble the RS pulse needs at least 100ns, fir the second nibble 50ns pulse is even OK. LCD_EN can be set to high at the same time data is provided.
This timing is also valid when using pull-up/down switching on LCD_RS/SDA line, keeping the voltages on the safe side :-).

73, Guido


On Mon, Nov 11, 2019 at 6:38 AM Hans Summers <hans.summers@...> wrote:
Hi Tom:

> I find that the sidetone issue in T102a occurs when the keyer menu is set for 
> straight key, but the issue does not occur not when set for an iambic paddle.  
> That's kind of curious.

Many thanks for this observation. I investigated and determined that the problem occurs because in straight key mode, the key state is continuously checked and actioned; in paddle modes, once key-down has started there is no further change to the TX state (and sidetone) until a defined period later e.g. 0.1 seconds for a 12wpm "dit". The continuous updates in straight key mode were resetting my new sidetone generation system. 

Easily fixed, just one line of code... now straight key sidetone is perfect too! 1.02b coming shortly. 

Hi Chopper:

> T1.02a loaded and working fine with the exception that as mentioned above 
> sidetone freq becomes distorted below 750  and as you get down to 500 or 600 
> the tone disappears and is simply key clicks.  Not a major issue but a change as 
> 1.01 had working tone at 500.  If you are having issues with side tone simply 
> increase it to 750.

I investigated this too and did not completely agree with your findings. From what I saw (or rather, heard) here the sidetone is working perfectly fine as your lower its frequency. However, it gets very quiet. You are left with whatever residual clicks exist (from Tx/Rx switching etc) that are unrelated to sidetone. But they are prominent because the sidetone volume is low. 

The low sidetone volume is due to two factors:

1) At low sidetone frequency, the timer period that generates the Pulse Width Modulation (PWM) is corresponding longer. The fixed amount (depending on volume setting) that is added/subtracted for the sidetone waveform generation is therefore proportionately smaller than it is at 700Hz; which results in a lower volume. 

2) The sidetone generation method is now much cleaner and more elegant than the previous system. Rather than a very short pulse whose harmonics are being filtered out, we now have effectively a proper 50% duty cycle squarewave at the chosen sidetone frequency. I think the CW filter does a much better job at filtering this, with the result that the attenuation is higher; remember at 500Hz the skirts of the CW filter mean already 15-20dB attenuation. 

By the way for fun I set the sidetone frequency to 350Hz, and I could just about barely hear the 2nd harmonic at 700Hz coming through the filter; this is satisfying because it is a very low level as one would expect for a nice clean squarewave (50% duty cycle). 

I could solve 1) by automatically adjusting the PWM frequency (which is 42kHz for 700Hz) so that the multiplier is higher at low sidetone frequencies, and 42kHz would be maintained; I'm a bit reluctant to fiddle with that in case it breaks something else ;-)   I could also have solved it by automatically increasing the size of the sidetone frequency PWM steps but, since the timer holds integers and the values are already fairly small, that would get complicated since I wouldn't be able to put fractional values in. 

Therefore just to keep everything very simple and not risk breaking anything (after all, most people just leave sidetone frequency at the default 700Hz), the simple solution I came up with is just increase the number of digits of the sidetone volume to 3 (the default volume is still 99, now displayed 099). This gives the operator more flexibility to increase the sidetone volume if lower sidetone frequencies are preferred and the volume is found to be too quiet. 

The maximum volume value that makes any sense is 0.5 * 20,000,000 / (60 * sideToneFreq) otherwise the width of the PWM for the sidetone frequency generation would exceed the timer period. So for example:
  • 700Hz sidetone: max volume 238
  • 600Hz sidetone: max volume 277
  • 500Hz sidetone: max volume 333
  • 400Hz sidetone: max volume 416
But don't worry, if you set a volume level higher than the "maximum" then the system automatically limits it according to the formula. 

Hi Guido:

> This older display seems to requires at least 60us delay after the
> first nibble write, and also require RS to be HIGH for an extended
> period of time. The newer display is not sensitive to this at all..

:-O   All the QRP Labs kits forever have never had those timings... there is no 60us delay after the first nibble write (before the next nibble write). Neither is RS high for an extended period of time. The only change I made to fix the problem with some of the displays is that I extended the pulse width of the LCD_E signal by 2 CPU cycles (100 nanoseconds). So to toggle the LCD_E signal the port pin is set high, then wait 2 CPU cycles, then set it low again. This puts the LCD_E signal back to the former behaviour, which is also the same as used on all other QRP Labs kits (Ultimate3S, VFO, Clock). 

Version 1.02b will be coming shortly... I just want to check the other feedback received in other threads and emails... 

73 Hans G0UPL

Re: #qcx Firmware 1.02: RIT tune rate #qcx

Werner Nunweiler
 

Hallo Axel,
 
die e-mails sind nicht für mich !!
 
73 de Werner DL1RTD
 
Gesendet: Montag, 11. November 2019 um 08:08 Uhr
Von: "Axel" <axel.friedrich_smail@...>
An: QRPLabs@groups.io
Betreff: Re: [QRPLabs] #qcx Firmware 1.02: RIT tune rate
Indeed, it works. Wonder what I did wrong.

Thank you, Jim!

73
Axel DF1ET

Re: Is my QCX 30 a write-off?

Alan G4ZFQ
 

Mike
Have attached an Excel sheet with all of my latest > readings (DVM).  Let me know if more needed.> Can't see any problems
around the processor & C47.
>Yes, I struggled a
bit with that sentence about the various processors. 8. Put P4 back in QCX 20 and still works OK
Hope that's more understandable.
Yes, the QCX30 is damaging the processors, as I'm sure you realised. The fault is carried through to a good QCX.
As far as I know this is only likely to happen if more than 5 V is applied, 5 V to the wrong pin or a short to ground on a critical pin.
There seems to be no actual list of expected voltages. (Maybe there is?)
I copy your results and looking at the schematic and manual add a few cross references.
The thing that stands out is pin 27, check again, maybe it's a typo?

(Dual purpose LCD reset /SDA expected 3.3 V I think maybe Hans has commented about this.) Yes https://groups.io/g/QRPLabs/message/29055?p=,,,20,0,0,0::Created,,qcx+sda,20,2,0,28593804 in here, I'm confused now, pin 27 is pulsed briefly to 5V, is it normally pulled down? The voltage list in the manual says 5V.

Other than that I hope someone else can come up with a suggestion.

IC2 -1 4.6
IC2 -2 0 D4
IC2 -3 4.9 D5
IC2 -4 4.9 D6
IC2 -5 4.9 D7
IC2 -6 0 EN
IC2 -7 4.9 VCC
IC2 -8 0 GND
IC2 -9 0.42 XTAL
IC2 -10 0.45 XTAL
IC2 -11 1.01 TX=2.3
IC2 -12 4.85 ROTA
IC2 -13 4.85 ROTB
IC2 -14 4.84 TX= 0 RX
IC2 -15 1.76 TX=2.5
IC2 -16 0 TX=4.9 KEY_OUT
IC2 -17 0.34
IC2 -18 4.8
IC2 -19 4.8 TX=0
IC2 -20 4.9 AVCC
IC2 -21 4.9 AREF
IC2 -22 0 GND
IC2 -23 2.45
IC2 -24 2.44
IC2 -25 0
IC2 -26 0
IC2 -27 0 SDA/LCD RS ?5V?
IC2 -28 3.34 SCL

A quick look at other voltages, C43 looks suspicious leading to the low voltages following it. But maybe leave that until the processor is working..

73 Alan G4ZFQ

Re: Firmware 1.02b

Kelly Jack
 

Uploaded 1.02b to my two QCXs and sidetone back to normal. Like the zip file too.

Thanks Hans.

73

Simon
VK3ELH

Re: More paddles and keys ...

David Wilcox
 

Beautiful.  Not “pretty” yet but made with your own hands.  I am sure your CW will be a joy to hear.  It has heart and soul...... 

David J. Wilcox K8WPE’s iPad

On Nov 10, 2019, at 5:27 PM, Ken KM4NFQ <km4nfq@...> wrote:


Greetings,

I have been working on a DIY Dual Lever Paddle made from brass & steel.
Here are a couple of work-in-progress snapshots:

<paddle001.png>
<paddle002.png>

I still need to bevel the sharp corners, and clean it up.
I had the steel and the brass in the shop, as well as the sterling silver for the contact points.
The springs are from the battery compartment of an old toy.
The main expenses were for brass screws, nuts, knurled nuts, and taps/drills.
I estimate that I have about $40.00 + time & labor invested in this paddle.
I have had fun making it.

Regards,
Ken, KM4NFQ "Not Fully Qualified"
https://github.com/muurtikaar/mega-morse-tutor

Re: Is my QCX 30 a write-off?

Mike Easterbrook
 

Hi Alan
Tks for feedback.  Have attached an Excel sheet with all of my latest readings (DVM).  Let me know if more needed.

Can't see any problems around the processor & C47.  Yes, I struggled a bit with that sentence about the various processors.  Let me try bullet points in chronological order:

1. Made up QCX 30 - worked OK. While aligning had the overvolt incident - blank LCD  - call this processor P1.
2. Troubleshooting after the incident - substituted new processor (P2) plus Si5351A & FST3523 - worked well enough to do preliminary alignment.
3. On next start-up buttons and encoder gone random - buzzing in ear piece on keying TX.
4. There was also a second new processor (P3) but can't remember exactly where this fits in the time scale.  This is now showing all the same faults as P2 
5. Made up QCX 20 - worked well (P4)
6. Did not want to compromise P4 by trying it in QCX30.
7. Instead put P2 in QCX 20 - QCX 20 now showing all same faults as QCX 30 with P2.
8. Put P4 back in QCX 20 and still works OK

Hope that's more understandable.

Mike




On Sun, Nov 10, 2019 at 8:48 PM Alan G4ZFQ <alan4alan@...> wrote:
  Mik

> The "buttons" section in troubleshooting refers specifically to board
> version 1/2.  Mine is version 4

Yes, but the symptoms are the same. A faulty component in this area
could be the reason. The modification was to sequence the power up
correctly, a faulty component (C47 dead?) could stop this.

> Looks like IC2 is implicated.  In the meantime I have built up my spare
> QCX 30 but for 20m.  This works well (except for low RF out (< 2w) but
> that's a matter for later).  I didn't want to risk replacing IC2 30m
> with the good IC2 20m
 >But putting the problem IC2 into QCX 30 seemed like a lower risk
strategy. ??

I'm confused, not sure what processor went where.
Now you are saying they are now both faulty?

> I've got a page-full of voltage readings and reluctant to post all these
> but happy to send direct to anyone with the time and patience!

You might as well post them, I wish more did! Long-distance diagnosis
needs as much help as possible. Wrong voltages at the processor are the
most likely thing to damage it.

73 Alan G4ZFQ



Re: #qcx Firmware 1.02: RIT tune rate #qcx

Axel
 

Indeed, it works. Wonder what I did wrong.

Thank you, Jim!

73
Axel DF1ET

Firmware 1.02b

Hans Summers
 

Hi all

I put firmware 1.02b here:

The changes in this version are regarding sidetone only, as discussed on the 1.02 thread:

1) Bug fix: Sidetone problem in straight key mode (bug introduced in 1.02)
2) Bug fix: Sidetone volume very low when using low sidetone frequencies; sidetone volume parameter has been increased to 3 digits 

Since a lot of people have provided positive feedback about 1.02 and 1.02a that they have installed themselves, and there are no known reproducible issues, I will now go ahead and ship all the pending orders using 1.02b today. 

So to re-iterate: anybody who ordered a QCX or a QCX chip from the shop, will get 1.02b shipped today (no 1.02 or 1.02a were shipped from here). 

73 Hans G0UPL

Re: T1.02 successful update

Hans Summers
 

Hi Bob
 
Observation: All seems to work per Hans' list except RIT drops out when switch is pressed to transmit message, does not return at end of transmission.

I was not able to reproduce this... I tried as many different permutations of settings as I could, but could not lose RIT after a message (or indeed, WITHIN the message transmission, when Full QSK is on). If you could provide me some detailed steps of how to produce it, I am happy to look into it further. 

73 Hans G0UPL

Re: Programming blank ATmega328P with QCX frimware

Hans Summers
 

Hi Nick

I will email you off-list

73 Hans G0UPL

On Mon, Nov 11, 2019 at 6:59 AM <n.j.austen@...> wrote:
Thanks for your info Allison.
I would really like to get my blown up unit working again as I am sure most of the components are fine - and it was so satisfying to hear it working so well on first powerup after the significant build effort. Great kit!

I am happy to buy a new programmed chip from Hans (but could not see how to do that on the site) but I think I have everything except the eeprom and fuses data.

[I am am buying a second unit for myself and a further one as a Christmas present  (which I will build) for a 10 year-old grandson who has discovered Morse.]

I understand the product security issue but maybe Hans is able to send the necessary files privately - with an NDA would be fine..

Best regards,
Nick.

Re: #qcx Firmware version 1.02 release #qcx

Hans Summers
 

Hi Tom:

> I find that the sidetone issue in T102a occurs when the keyer menu is set for 
> straight key, but the issue does not occur not when set for an iambic paddle.  
> That's kind of curious.

Many thanks for this observation. I investigated and determined that the problem occurs because in straight key mode, the key state is continuously checked and actioned; in paddle modes, once key-down has started there is no further change to the TX state (and sidetone) until a defined period later e.g. 0.1 seconds for a 12wpm "dit". The continuous updates in straight key mode were resetting my new sidetone generation system. 

Easily fixed, just one line of code... now straight key sidetone is perfect too! 1.02b coming shortly. 

Hi Chopper:

> T1.02a loaded and working fine with the exception that as mentioned above 
> sidetone freq becomes distorted below 750  and as you get down to 500 or 600 
> the tone disappears and is simply key clicks.  Not a major issue but a change as 
> 1.01 had working tone at 500.  If you are having issues with side tone simply 
> increase it to 750.

I investigated this too and did not completely agree with your findings. From what I saw (or rather, heard) here the sidetone is working perfectly fine as your lower its frequency. However, it gets very quiet. You are left with whatever residual clicks exist (from Tx/Rx switching etc) that are unrelated to sidetone. But they are prominent because the sidetone volume is low. 

The low sidetone volume is due to two factors:

1) At low sidetone frequency, the timer period that generates the Pulse Width Modulation (PWM) is corresponding longer. The fixed amount (depending on volume setting) that is added/subtracted for the sidetone waveform generation is therefore proportionately smaller than it is at 700Hz; which results in a lower volume. 

2) The sidetone generation method is now much cleaner and more elegant than the previous system. Rather than a very short pulse whose harmonics are being filtered out, we now have effectively a proper 50% duty cycle squarewave at the chosen sidetone frequency. I think the CW filter does a much better job at filtering this, with the result that the attenuation is higher; remember at 500Hz the skirts of the CW filter mean already 15-20dB attenuation. 

By the way for fun I set the sidetone frequency to 350Hz, and I could just about barely hear the 2nd harmonic at 700Hz coming through the filter; this is satisfying because it is a very low level as one would expect for a nice clean squarewave (50% duty cycle). 

I could solve 1) by automatically adjusting the PWM frequency (which is 42kHz for 700Hz) so that the multiplier is higher at low sidetone frequencies, and 42kHz would be maintained; I'm a bit reluctant to fiddle with that in case it breaks something else ;-)   I could also have solved it by automatically increasing the size of the sidetone frequency PWM steps but, since the timer holds integers and the values are already fairly small, that would get complicated since I wouldn't be able to put fractional values in. 

Therefore just to keep everything very simple and not risk breaking anything (after all, most people just leave sidetone frequency at the default 700Hz), the simple solution I came up with is just increase the number of digits of the sidetone volume to 3 (the default volume is still 99, now displayed 099). This gives the operator more flexibility to increase the sidetone volume if lower sidetone frequencies are preferred and the volume is found to be too quiet. 

The maximum volume value that makes any sense is 0.5 * 20,000,000 / (60 * sideToneFreq) otherwise the width of the PWM for the sidetone frequency generation would exceed the timer period. So for example:
  • 700Hz sidetone: max volume 238
  • 600Hz sidetone: max volume 277
  • 500Hz sidetone: max volume 333
  • 400Hz sidetone: max volume 416
But don't worry, if you set a volume level higher than the "maximum" then the system automatically limits it according to the formula. 

Hi Guido:

> This older display seems to requires at least 60us delay after the
> first nibble write, and also require RS to be HIGH for an extended
> period of time. The newer display is not sensitive to this at all..

:-O   All the QRP Labs kits forever have never had those timings... there is no 60us delay after the first nibble write (before the next nibble write). Neither is RS high for an extended period of time. The only change I made to fix the problem with some of the displays is that I extended the pulse width of the LCD_E signal by 2 CPU cycles (100 nanoseconds). So to toggle the LCD_E signal the port pin is set high, then wait 2 CPU cycles, then set it low again. This puts the LCD_E signal back to the former behaviour, which is also the same as used on all other QRP Labs kits (Ultimate3S, VFO, Clock). 

Version 1.02b will be coming shortly... I just want to check the other feedback received in other threads and emails... 

73 Hans G0UPL

Re: Programming blank ATmega328P with QCX frimware

Nick Austen
 

Thanks for your info Allison.
I would really like to get my blown up unit working again as I am sure most of the components are fine - and it was so satisfying to hear it working so well on first powerup after the significant build effort. Great kit!

I am happy to buy a new programmed chip from Hans (but could not see how to do that on the site) but I think I have everything except the eeprom and fuses data.

[I am am buying a second unit for myself and a further one as a Christmas present  (which I will build) for a 10 year-old grandson who has discovered Morse.]

I understand the product security issue but maybe Hans is able to send the necessary files privately - with an NDA would be fine..

Best regards,
Nick.