Date   

Re: Receiver module kit image rejection figure

jmh6@...
 

Hi Pim,

I meant when the frequency was close to the 'center' frequency. My understanding is that many transmit signal designs do not try to send data close to the center frequency for that reason. The other major problem is back feeding of the carrier to the input which is a different problem.

I remember listening to a PA system with few Hz frequency shifter in the path to cut down feedback problems. Worked pretty well.

I guess it 'seems to me' that is 'should' be quite a bit better, but have yet to actually build one to test. There are not too many audio digitizers with 3 inputs!!! So there would be quite a bit of work to do.

I suppose the next step would be a full multi-channel synchronous receiver with multiple antenna inputs and some sort of smart combiner.

Lots of fun :).

On Fri, 6 Dec 2019, pa2pim@gmail.com wrote:

On Wed, Dec 4, 2019 at 04:36 PM, <jmh6@nhfn.net> wrote:
Hi Allison and all,

Has anyone done a 3 phase receiver rather than an I Q receiver. I seems
to me that near zero hertz the performance 'should' be 'much' better as
there are no near-zero signals to try to digitize.

Lots of fun :).
Interesting question!
What do you mean by "Near-Zero"?
Amplitude, frequency or phase?
Aren't all those 3 parameters independent of the number of phases in a (poly) phasing receiver/transmitter?
Triggered by a question from someone in the audio synthesizer world  (ttp://www.nicksworldofsynthesizers.com/) I did some preliminary work in 2017 on N-phase polyphase
networks to be used in SSB receivers and transmitters. 
It was interesting but it turns out that using more then 2 phases, in push-pull or not, does not gain you anything useful. You need different amplitudes and lots more
components.
The graphics and math behind it was fun thought, see attached.
By the way, there is lot's of interesting things going on in the audio synthesizer world which has a relation with Radio. A Moog Bode audio frequency shifter from the 70's
is basically a SSB transmitter with a very low carrier frequency. The patent and schematics can be found on the Internet. It has it's issues around a 0 Hz. shift. In the
end I came up with the attached design. Also a paper tiger so far but, again, lots and lots of fun.
Pim


Re: Receiver module kit image rejection figure

pa2pim@...
 

On Wed, Dec 4, 2019 at 04:36 PM, <jmh6@...> wrote:
Hi Allison and all,

Has anyone done a 3 phase receiver rather than an I Q receiver. I seems
to me that near zero hertz the performance 'should' be 'much' better as
there are no near-zero signals to try to digitize.

Lots of fun :).
Interesting question!
What do you mean by "Near-Zero"?
Amplitude, frequency or phase?
Aren't all those 3 parameters independent of the number of phases in a (poly) phasing receiver/transmitter?

Triggered by a question from someone in the audio synthesizer world  (ttp://www.nicksworldofsynthesizers.com/) I did some preliminary work in 2017 on N-phase polyphase networks to be used in SSB receivers and transmitters. 
It was interesting but it turns out that using more then 2 phases, in push-pull or not, does not gain you anything useful. You need different amplitudes and lots more components.
The graphics and math behind it was fun thought, see attached.

By the way, there is lot's of interesting things going on in the audio synthesizer world which has a relation with Radio. A Moog Bode audio frequency shifter from the 70's is basically a SSB transmitter with a very low carrier frequency. The patent and schematics can be found on the Internet. It has it's issues around a 0 Hz. shift. In the end I came up with the attached design. Also a paper tiger so far but, again, lots and lots of fun.

Pim


Re: QSX

Andrew Stopford
 

Thanks for the update Hans.  Look after yourself and your family first.  Please do not feel under any pressure to rush the QSX.  I would much rather it was only released when you felt completely happy with its quality.  I would not want to feel i was building something that had been rushed and had issues. 

Best wishes Hans.  

Andrew
M0MVA            


Re: QCX 5W CW Transceiver Troubles Part III

joseph.corbin@...
 

Bill,

The relative humidity in the original location is about 50% and the new location has a relative humidity of about 30-40%. We weren't wearing wool socks but we were both wearing 100% polyester shirts, if that makes a difference haha.

Skip,

In our original test, when it worked well, we started by using earphones, then we switched to a speaker with an aux cord so that more people could hear it. We only used the earphones when we went to the new location. But other than that, there were no other changes that we can recall. We are currently using a Keithley 2231A-30-3 Triple Channel DC Power Supply at 12 V. We will get our hands on a battery and see if that works. Our QCX was sitting on the standoffs but I'll confirm that there isn't a short underneath.

Jim,

Thanks! We will definitely try a battery and report what happens. Also, I'll be sure to make sure there is nothing metallic nearby when we fire it up again. Although I don't think that is the issue since it worked in the same conditions earlier this morning. But we'll see what happens! If ever you find yourself back in Ottawa, KS during the school year, feel free to stop by and see our set up!

Thank you all for the helpful and quick responses!

Joe 
--

Joseph Corbin

President of the Engineering Club
Ottawa University
Ottawa, KS


Re: QSX

Roland Williams
 

Dyslexia lures, surely. 

Personally I find auto-corrupt a very interesting aspect of modern life ... just saying.

Roland
AE6VL

On Dec 6, 2019, at 11:38 AM, Alan Richmond via Groups.Io <richmond@...> wrote:

Dyslexia rules KO.

On topic, you can have a good job, an inexpensive job, or a quick job, but you can't have all three.
Guess which one I can do without. Would anyone argue with that?

Best wishes, Hans

Alan
GU3ONJ


Re: QCX 5W CW Transceiver Troubles Part III

Jim Mcilroy
 

Hi Joe

Congrats on getting some action out of your QCX

Before warming up a soldering iron I suggest you make sure it is not sitting on anything metallic nearby.

At my QTH I have taken to using lids from scrap box files which are thick cardboard but you may have a more elegant solution  :)

Use a battery to power the QCX. As long as you don't key it up a simple PP3 9V battery is probably good enough for a short while.

If you have a dummy load connect that to the antenna socket to be on the safe side.

See what you can hear then.

73

Jim

PS I've been to Ottawa Uni for a brief visit in the last century. Went to see one of the profs who was into precision timing. The name escapes me for now. A nice part of the world.

On 06/12/2019 18:25, joseph.corbin@... wrote:
Hello again all from Ottawa University!

The good news is: my partner, Will, and I were able to finally get our little radio to work well. We were able to send and receive signals this morning while testing it.

The bad news is: We attempted to move the radio to a different location in our building without making any other changes to the radio. But, when we powered it up at the new location, we only heard a loud, bee-like noise. We were unable to receive the simple signals being sent to us by our professor from within the same building. We checked and double-checked the settings on the radio itself. But we don't see or understand what the problem is. We then attempted to bring it back to the original location and try again. Unfortunately, we had the same constant, noisy tone that, quite frankly, sounds like a little sweat bee flying right into my ears (we used both headphones and speakers while testing). It's as if the radio is failing to filter out the noise properly. We are now wondering if there is a hardware problem that might be associated with this noisy tone.

Any help would be greatly appreciated! Also, we are still quite new at this so we may need some help understanding the terminology and functionality associated with our little transceiver.

Thanks!

Joe
--

Joseph Corbin

President, Engineering Club
Ottawa University
Ottawa, KS


Re: Happy Holidays, Community! From KW0P

Gary Bernard
 

Really clever, I love it.
Gary W0CKI


-----Original Message-----
From: Kurt <kurt.schanaman@...>
To: QRPLabs <QRPLabs@groups.io>
Sent: Fri, Dec 6, 2019 4:39 am
Subject: [QRPLabs] Happy Holidays, Community! From KW0P

Couldn't help but to feature my wonderful, operational QCX transceiver in my holiday greeting video. Wishing Hans, and all of you, a very merry "Ham Christmas!"

https://www.brighteon.com/35a4bb5f-c5c0-417b-95f7-b2ded8476f12


Re: QSX

Alan Richmond
 

Dyslexia rules KO.

On topic, you can have a good job, an inexpensive job, or a quick job, but you can't have all three.
Guess which one I can do without. Would anyone argue with that?

Best wishes, Hans

Alan
GU3ONJ


Re: QCX 5W CW Transceiver Troubles Part III

Skip Davis
 

Other than location what else might have been changed? What kind of power supply are you using? If it is different and is a switching supply it might be your problem. Try a battery to power up the QCX and see if it goes away. Also is your QCX sitting on the standoffs if not you may have set it on something that caused a short under the board.

Skip NC9O


Re: JS8mode heartbeat beacon...

jmh6@...
 

Hi Alan and all :),

I have loaded code into my QCX with FT8/JS8 in mind. Not running yet, but clearly possible.

I don't know if JS8 supports either hex messages or plain ASCII, but FT8 does.

I am thinking that some sensor processor sends serial data to the QCX and it buffers and encodes it and sends it out.

A normal FT8 receiving system decodes the incoming packets and displays the received data.

The serial data could even come from a simple keyboard. You type and the QCX sends packetized keyboard data out as FT8/JS8 RF signals.

Lots of fun :).

On Thu, 5 Dec 2019, Alan de G1FXB wrote:

U3 and QCX requires it to be added to the firmware
I think Hans already has already experimented with FT8, in addition a code module was written by one of our members.
The problem may be more of a time and space continuum in an existing well utilised 328.
We are going to need an upgraded U3 / QCXplus with an SD card slot to handle much more.......  :-)
QSX who knows for sure.
the features page suggests  it's digital ready with a number of inbuilt modes.
While other features are added by an external USB device, PC, Laptop, mention is also made of an option of built in RPi Zero.......
In which case we can administrate those features ourselves, and not require support from Hans who can maintain his own closed QSX code base independently.
Alan
On 05/12/2019 18:48, Dean Smith wrote:
I see OZ2M has created Arduino code for sending JS8 heartbeat message beacon with rf zero project.
This mode is very simular to FT8. just expanded rather than signal and call exchanges, with chat modes, mailbox, comm speeds, beacon mode,APRIS . connecting via
other stations. These are a few of it's features.
 Is there any way the humble U3/QCX,QSX would be able to make use any of this emerging weak signal mode??
--
Smell Czech corruptions are inevitable


Re: QSX

Bill Cromwell
 

Hi Ken,

I for one am in 'need' of an 80 meter rig. Of course the QSX will cover that band..but I want one pretty soon. I will be ordering it and then building it next month. I have another list member's radio working through weak spots and should be done with that soon. My own gear needs attention - plus that 80 meter QCX. Anticipating the QSX is not a reason for me to abandon the QCX. They are just too inexpensive for that. I expect to buy a QSX when they are available too.

I have some old computer gear here and sometimes use it. That old stuff still does everything it always did and usually is done before the bloatware computers can get booted up. And twice for MS Windows!

73,

Bill KU8H

On 12/6/19 1:15 PM, Ken watson wrote:
I was around at the dawning of the PC era. There were many new PC's being introduced and improved on at the time. Many operating systems etc. There were at least two companies selling PC's that killed themselves by announcing a new product was coming out...which killed present sales as buyers, in anticipation, lead to a LOT of unsold inventory. Since the newly built but unsellable products were financial write off's, the companies no longer had revenue to pay employees and suppliers. ...End of the company.
God Speed Hans, looking forward to getting one of your QSX radios.
Ken
K7KLW
--
bark less - wag more


Re: QCX 5W CW Transceiver Troubles Part III

n4qa at_hotmail.com
 

Hi Joe.
Just wondering what is the relative humidity in your building this time of year.
Best of luck & 72 / 73,
Bill, N4QA
ps
Hope you guys weren't transporting the QCX while wearing your wool socks :0)


Re: JS8mode heartbeat beacon...

Dean Smith
 

Sorry tones my phone not spell savvy at the moment.


Re: JS8mode heartbeat beacon...

Dean Smith
 

The thing is how much further can this method be taken? Sub noise floor comms using sound card rig interface is getting to a point where there seems to be little further to go with a bunch of to es. Where next? Hmm anyone....


Re: JS8mode heartbeat beacon...

Andy Brilleaux <punkbiscuit@...>
 

On Fri, Dec 6, 2019 at 02:35 PM, David Goodrow wrote:
I believe a low cost JS8 transceiver would be very popular.
Give in a few weeks and it will be obsolete ,and a yet another weak signal digimode has taken over ;-)

- Andy -


QCX 5W CW Transceiver Troubles Part III

joseph.corbin@...
 

Hello again all from Ottawa University!

The good news is: my partner, Will, and I were able to finally get our little radio to work well. We were able to send and receive signals this morning while testing it.

The bad news is: We attempted to move the radio to a different location in our building without making any other changes to the radio. But, when we powered it up at the new location, we only heard a loud, bee-like noise. We were unable to receive the simple signals being sent to us by our professor from within the same building. We checked and double-checked the settings on the radio itself. But we don't see or understand what the problem is. We then attempted to bring it back to the original location and try again. Unfortunately, we had the same constant, noisy tone that, quite frankly, sounds like a little sweat bee flying right into my ears (we used both headphones and speakers while testing). It's as if the radio is failing to filter out the noise properly. We are now wondering if there is a hardware problem that might be associated with this noisy tone.

Any help would be greatly appreciated! Also, we are still quite new at this so we may need some help understanding the terminology and functionality associated with our little transceiver.

Thanks!

Joe
--

Joseph Corbin

President, Engineering Club
Ottawa University
Ottawa, KS


Re: QSX

Ken watson
 

I was around at the dawning of the PC era. There were many new PC's being introduced and improved on at the time. Many operating systems etc. There were at least two companies selling PC's that killed themselves by announcing a new product was coming out...which killed present sales as buyers, in anticipation, lead to a LOT of unsold inventory. Since the newly built but unsellable products were financial write off's, the companies no longer had revenue to pay employees and suppliers. ...End of the company.

God Speed Hans, looking forward to getting one of your QSX radios.

Ken
K7KLW


Re: QSX

Ryan Flowers
 

Well said Hans, and I'm sure everyone appreciates hearing it straight from you. Allison, you brought out an interesting point: The unknown unknowns. It's so often that we don't know what we don't know until we know we don't know it. 

I personally experienced it when I was trying to multi-band the BITX40, exploring the limits of its PA layout and what not. At that point, I didn't even know that layout mattered! Now I know better, and that took a lot of experimenting to understand first hand.

I'm looking forward to seeing what other projects have evolved out of this, and am looking forward to the QSX when it's ready

--
Ryan Flowers - W7RLF
The BITX40 FAQ


Re: QSX

Bill Cromwell
 

Hi,

Lexdysia may be worse that spell wreck. I have my spelling faerie configured to 'suggest only' and NOT to auto-correct anything. All of the typos you find in my messages are personally hand-crafted by *me*. I do not need a robot to decorate my own genuine mistakes.

73,

Bill KU8H

On 12/6/19 12:51 PM, ajparent1/KB1GMX wrote:
One thing in life is that big projects are really big and getting them built means
solving many small, nagging and frustrating problems.   Then one day you
have subdued the dragons and start testing...  When you get all that set right
it is a very satisfying thing.  As it is only then you can look back and see the
trail of decisions and solved problems that must be made to get to the a
desirable result.
Along the way there are project and events that require attention.  Some call
that distractions, many however, realize that creative efforts be they art or
engineering require inspiration and that essential "ah ha" moment that is
part of the problem solving path to a envisioned result.
As a designer and builder I understand that.   As others suggested and we
see those assembling a simpler radio makes them an expert.  Having an
opinion is good and may lead to things.   Becoming expert is a lot of self
training and a lifelong process.  Turns out the more you know the more you
have to learn, because, you actually don't know.   At least I don't.  That's
not a bad thing.   It is just the creative challenge and is how the technical
passion works.  Pushing ones personal skills further on something new
is how that happens.  You learn something new.
I will enjoy what I see when I see it.  Its not like I haven't 2e16 projects
to take on.  Boredom is not an option.  ;)
I really hate spell wreck depsite being very despondent on it.
Allison
---------
Please reply on list so we can share.
Off list email goes to trash, I had to due to scrapers.
--
bark less - wag more


Re: QSX

ajparent1/KB1GMX
 

One thing in life is that big projects are really big and getting them built means 
solving many small, nagging and frustrating problems.   Then one day you 
have subdued the dragons and start testing...  When you get all that set right
it is a very satisfying thing.  As it is only then you can look back and see the 
trail of decisions and solved problems that must be made to get to the a 
desirable result.

Along the way there are project and events that require attention.  Some call 
that distractions, many however, realize that creative efforts be they art or 
engineering require inspiration and that essential "ah ha" moment that is
part of the problem solving path to a envisioned result.

As a designer and builder I understand that.   As others suggested and we 
see those assembling a simpler radio makes them an expert.  Having an
opinion is good and may lead to things.   Becoming expert is a lot of self
training and a lifelong process.  Turns out the more you know the more you
have to learn, because, you actually don't know.   At least I don't.   That's
not a bad thing.   It is just the creative challenge and is how the technical
passion works.  Pushing ones personal skills further on something new
is how that happens.  You learn something new.

I will enjoy what I see when I see it.  Its not like I haven't 2e16 projects 
to take on.  Boredom is not an option.  ;)

I really hate spell wreck depsite being very despondent on it.

Allison
---------
Please reply on list so we can share.
Off list email goes to trash, I had to due to scrapers.