Date   

Re: QCX CW transceiver

Stephen Farthing G0XAR JO92ON97
 

Hi Guys, 

One option is Beeswax. This has been recommended by Rev George Dobbs as the best way to secure coil windings. It’s environmentally good, non toxic and easily available from hardware stores and on line. A block of beeswax goes a long way! 

Regards from a wet and windy England,

Steve G0XAR


Re: Receiver Module

Alan G4ZFQ
 

Roger,
Yes the the band noise does increase when antenna connected.
That's all you need.
I was going to suggest you tried a core with a mix more suited to lower frequencies but it can be a problem getting the bandwidth.

cannot operate without Polyphase board because my laptop only has mono soundcard so cannot use I Q "mode".
Have you dug deeply into Sound Properties and maybe the soundcard software?
Many laptops are mono by default but the "microphone input" is able to be configured into a half-decent stereo system.

73 Alan G4ZFQ


Re: QCX CW Instructions Comments

Hans Summers
 

Hi Richard

Thanks for the comments. I will check, but I think most of these are already incorporated in the latest manual version. Your 1.08 document is quite old!

73 Hans G0UPL 

On Sat, Dec 8, 2018, 03:50 Richard Clemens <rich.clemens@... wrote:
Great instructions - with a couple of suggestions (based on Version 1.08)
   Drawing by WA4MZS for T1 is very helpful
   Would nice to know the approximate length of wire needed for each toroid
   Error in Step 3.70 R47 is on top left (not top right)
   Nice to know wire was #28 thanks to WA4MZS again
   It would be good to assure text and image for same step appear on same page


QCX CW Instructions Comments

Richard Clemens
 

Great instructions - with a couple of suggestions (based on Version 1.08)
   Drawing by WA4MZS for T1 is very helpful
   Would nice to know the approximate length of wire needed for each toroid
   Error in Step 3.70 R47 is on top left (not top right)
   Nice to know wire was #28 thanks to WA4MZS again
   It would be good to assure text and image for same step appear on same page


Re: Receiver Module

Roger G4IUP
 

Hi Curt.  Yes the the band noise does increase when antenna connected. I cannot operate without Polyphase board because my laptop only has mono soundcard so cannot use I Q "mode". Thanks for your response. 
73 Roger



Re: Receiver Module

Curt wb8yyy
 

Roger

Much could be going on here. First note that atmospheric and man made noise can he much higher down there.  Likely you have enough gain to hear band noise, does the noise level increase when you attach the antenna? If not, then do see what is up. 

sure, okay, see what is documented by the designer on the polyphase, and maybe see what happens without it on 474 khz.

Curt


Receiver Module

Roger G4IUP
 

Hi all, I am building a multiband WSPR receiver using this module and Polyphase board. It is working well on 3.5,7,10 and 14 mhz. However I am finding the sensitivity lacking on 474.2 khz. I was thinking that more turns on the trifilar transformer possibly on a larger core would help. Any thoughts?
73, Roger G4IUP


Re: QCX CW transceiver

jjpurdum
 

Garry:

Good to know. Most of the time I just peel away enough to remount the toroid.

Jack, W8TEE

On Friday, December 7, 2018, 11:47:22 AM EST, Garry48 <ggkraemer@...> wrote:


Jack,
 
It is much easier to remove hot glue using 70-90% Isopropyl Alcohol.
Put a little alcohol on the glue, let it sit for a bit and it comes off without leaving a trace.
 
Garry / WD0DUD
 
From: jjpurdum via Groups.Io
Sent: Friday, December 07, 2018 7:41 AM
To: QRPLabs@groups.io
Subject: Re: [QRPLabs] QCX CW transceiver
 
I kinda like hot glue for things like holding toroids in place. The reason is because, if I need to change it, at least I can reheat the glue with my hot air (rework) gun and soften the glue up to the point where I can remove it.
 
Jack, W8TEE
 
On Friday, December 7, 2018, 9:30:59 AM EST, R.Putnam via Groups.Io <kairos1@...> wrote:
 
 
I used super glue to stop T1 springing apart . I would have been in real trouble if I had needed to remove turns from T1!  One thread recommended making making T1
the first item to be soldered to the PCB .

Richard G0ILN Fist 398


It is the 7th of December - Worldwide QRSS Celebration is 22 days away.

David R. Hassall WA5DJJ
 

Dear QRPLabs members,

 

Today is the 7th of December.   We have just 22 days left until the WORLDWIDE QRSS CELEBRATION from 0000Z December 31st, 2018 until 2400Z January 1st, 2019.   There are a lot of grabbers just waiting for your signals spread all over the world.   Propagation is expected to be tough this year with the high bands very iffy as to any long range activity but you never know.  10 Meters sometimes opens up worldwide in December and January so we can hold out hope for those bands.   The WA5DJJ ALL BAND HF QRSS GRABBER is working well from 160M through 12M.   I am having trouble with the 10M and 630M receivers but hope to get some progress made on making them work.  

 

So those of you who are procrastinating,  The time is starting to catch up with you.   A big winter storm is now in progress across the United States so outside antenna work is going to be difficult.   But you can drag your U3S QRSS transmitter off the shelf and dust it off and see if it still works.   Cold winter days are sometimes the best times to work on your MEPT transmitter as there is nothing else to do.

So get at it.  

 

I have a modification to my ALL BAND QRSS HF GRABBER on 30M where I am receiving both QRSS and WSPR signals using the same receiver.  The QRSS signals go to my grabber spectrum analyzer and the WSPR spots are going to WSPRNET.ORG.   I have been able to get my Raspberry Pi to run both LOPORA  and WSJT-X in the WSPR mode at the same time.  I am hoping to expand this configuration to 80M, 40M and 20M before the QRSS WORLDWIDE CELEBRATION.  Right now you can try it out on 30M and see how you like it.

 

Hope to see you all on my grabber this year. Take care and have fun.

73 Dave Hassall WA5DJJ  Las Cruces, New Mexico

Website: http://www.zianet.com/dhassall/

QRSS SUPER GRABBER WEBSITE: http://www.qsl.net/wa5djj/

 


Re: QCX CW transceiver

Garry48
 

Jack,
 
It is much easier to remove hot glue using 70-90% Isopropyl Alcohol.
Put a little alcohol on the glue, let it sit for a bit and it comes off without leaving a trace.
 
Garry / WD0DUD
 

From: jjpurdum via Groups.Io
Sent: Friday, December 07, 2018 7:41 AM
To: QRPLabs@groups.io
Subject: Re: [QRPLabs] QCX CW transceiver
 
I kinda like hot glue for things like holding toroids in place. The reason is because, if I need to change it, at least I can reheat the glue with my hot air (rework) gun and soften the glue up to the point where I can remove it.
 
Jack, W8TEE
 
On Friday, December 7, 2018, 9:30:59 AM EST, R.Putnam via Groups.Io <kairos1@...> wrote:
 
 
I used super glue to stop T1 springing apart . I would have been in real trouble if I had needed to remove turns from T1!  One thread recommended making making T1
the first item to be soldered to the PCB .

Richard G0ILN Fist 398


Re: #wspr #u3s My first U3S ... WSPR not quite working #wspr #u3s

Bruce K1FFX
 

Thanks for the info and pointer to your notes, Alan ... much appreciated.

Best -

Bruce K1FFX


Re: QCX CW transceiver

jjpurdum
 

I kinda like hot glue for things like holding toroids in place. The reason is because, if I need to change it, at least I can reheat the glue with my hot air (rework) gun and soften the glue up to the point where I can remove it.

Jack, W8TEE

On Friday, December 7, 2018, 9:30:59 AM EST, R.Putnam via Groups.Io <kairos1@...> wrote:


I used super glue to stop T1 springing apart . I would have been in real trouble if I had needed to remove turns from T1!  One thread recommended making making T1
the first item to be soldered to the PCB .

Richard G0ILN Fist 398


Re: QCX CW transceiver

R.Putnam
 

I used super glue to stop T1 springing apart . I would have been in real trouble if I had needed to remove turns from T1!  One thread recommended making making T1
the first item to be soldered to the PCB .

Richard G0ILN Fist 398


Re: #wspr #u3s My first U3S ... WSPR not quite working #wspr #u3s

Alan G4ZFQ
 

What is the recommended TCXO?
Bruce,

There is no recommended, as you say the one mentioned, the FOX, is a jumper. Some use it on HF with no apparent problems although my obsevations suggest that under poor propagation spots could be lost on the higher bands.

I've kept notes on those reported here:- https://sites.google.com/site/g4zfqradio/incircuitprogramatmel168#Testing%20TCXOs
Would it be better for me to order up a new synthesizer kit, rather than
try to remove the crystal from my current board?

I have about 5 I play with. They also fit the VFO and, depending how you build it, the Progrock.

73 Alan G4ZFQ


Re: U3S Case front panel push buttons

Brian Summers
 

Mouser list a switch 629-GPB023B05BR which looks like it will fit the same diameter hole. Probably much better quality I would think.

Brian VE7JKZ

On 12/6/2018 9:44 AM, Alan de G1FXB via Groups.Io wrote:
To prevent excess heat reaching the switch body, clamp a haemostat* between the switch and the tag.
*A pair of needle nose or pointed pliers held shut with an elastic band is a good substitute.

Alan
On 06/12/2018 17:02, Curt M. wrote:
I'm sure there's probably something else out there but it seems like the key with those switches is not put too much heat on the terminals when you solder the wires in place.  They seem to act very similar to relay contacts when you put too much current across them.  We used to always say that the contacts were "gulled", not sure if that is the correct spelling or even the correct term but that's what we used to say where I worked a number of years ago.

When I solder those terminals I quickly push and release the button multiple times as soon and I pull the soldering iron tip away.  There were times a while back that the button would stick on the in position and it was from too much heat.  Now they seem to hold up better with a lighter touch with iron but those switches are not good quality right out of the gate so I know what you are saying.


Re: QCX CW transceiver

N3MNT
 

I used thin strips of masking tape to keep coil neat.  One possible for those having issues getting the TI wires in the correct holes would be a thin piece of mica about 1" x 1" with the proper hole spacing so wires could  be properly spaced making it easier to mount .


Re: No GPS data with U3S - For Hans

geoff M0ORE
 

First send appeared here OK .

On 12/6/2018 10:39 PM, Brian Summers wrote:

Strange, I sent this several hours ago but it never appeared. Let me try again.

Brian VE7JKZ



-------- Forwarded Message --------
Subject: Re: [QRPLabs] No GPS data with U3S - For Hans
Date: Thu, 6 Dec 2018 09:32:23 -0800
From: Brian Summers <ve7jkz@...>
Reply-To: QRPLabs@groups.io
To: QRPLabs@groups.io


I've managed to come up with a procedure for repeating my problem. I've got the unit mode indices programmed so it operates as follows:

1. Power on U3S. Ultimate3S 3.12a appears. Then the display switches to GPS data as it should.

2. Press the Menu button once and the display reads:

0]-0-000,473,000
TX CW-------00-0

3. Press the menu button again and the displays reads:

1]-0-000,473,000
TX CW-------00-0

4. All the above really shows is that I have the same message in mode index 0 and 1. Not intentionally I might add. I'm new to the U3S so this is all happenstance.

5. Now power off/on. Once again the Ultimate3S screen appears followed by GPS data.

6. Press the menu button once and see the display as para 2 above.

7. Now press the edit button twice to enable. The display will show:

0] 0 000,473,000
TX CW       00 0

8. Power off/on. The Ultimate 3S screen appears, the GPS data does not appear and instead the display shows as follows. The beating heart appears where it should.

0] 0 000,473,000
TX CW

9. Press the menu button again and see:

0] 0 000,473,000
TX CW       00 0

10. Press the menu button again and see:

1]-0-000,473,000
TX CW-------00 0

11. You can see from 8 and 9 that I've created two messages identified with mode index 0]. Now you can repeat from para 8. The unit goes directly from the Ultimate 3S screen to the first mode setting every time, bypassing the GPS data screen. It all repeats.

12. To recover from this situation power off/on as para 8, go to the screen shown in para 9, then press the edit button twice to disable the mode setting. Now power off/on and GPS data will follow the Ultimate 3S screen.

Doubtless there are other ways of demonstrating this but the above is repeatable for me. Here's hoping that when I post this the formatting does not change........

Brian VE7JKZ



On 11/30/2018 8:34 AM, Brian Summers wrote:
GM Alan,

For the record my notes show the following when trying to set up for 473Khz.

0] 0 000,473,000 then on the line below, TX CW.  Call this message A

now press the menu key and the display shows:

0] 0 000,473,000 then on the line below, TX CW      00 0.  Call this message B.

Under these conditions there is no GPS data. Now disable message B, switch off/on, then GPS data appears immediately following the Ultimate 3S information screen.

I suppose I could spend more time on this trying other modes and messages but it can be very time consuming particularly with the case mounted push button switches which I find to be very flimsy and troublesome. For now I'm content to know that if I have no GPS data and scroll the menu to find two messages with the same number, I know what to do about it.

73 Brian VE7JKZ


On 11/30/2018 2:42 AM, Alan G4ZFQ wrote:
Strange thing is, no error message appears.

 Brian,

I guess if Hans knew it would happen there would be no error message because he had put it right!

>when two almost identical modes are set with the same band number

Maybe let Hans know exactly what settings, what are "almost identical" modes?

73 Alan G4ZFQ










Re: si5351a #synth

Dave New, N8SBE
 

Hans,

Had a crystal oscillator issue a few years ago that cause a lot of head scratching.  We had been producing said module for several years with no problems, when suddenly we had a rash of dead modules (no oscillation) after they had been outside overnight in desert air that veered toward freezing, but not below.

We found ultimately that the oscillator was failing to start under low temperature conditions, but our modules are meant to operate over -40C to 85C and had been tested to that repeatedly over the current production runs.

Long story short (too late), we found that the original design had been marginal, in that the recommendation of the microprocessor manufacturer didn't line up with the recommendations of the crystal supplier.  Production variation had exposed the margin, and thus, we started seeing failures at low temperature.  So, after a lot of back and forth, we lowered the value of the ballast resistor in the tank circuit to increase the feedback, and voila! all the issues went away.

Several more years (and a few million) modules later, we have never seen another oscillator failure in the field.

Lesson:  Every component has a data sheet, and often, they DON'T agree with those components' datasheets they need to interface to.  Sometimes it takes a whole engineering team (and their OEM customer breathing down their back) to bash heads (and those of the component suppliers) until an optimal solution is found.

73,

-- Dave, N8SBE

-------- Original Message --------
Subject: Re: [QRPLabs] si5351a #synth
From: "Hans Summers" <hans.summers@...>
Date: Wed, December 05, 2018 11:30 am
To: QRPLabs@groups.io

Hi Richard

Thanks for your comprehensive reply. How do you find time - do you ever sleep?

A lot more than I used to, unfortunately... until I'm fully back to normal health levels I sleep all I can!

2. What spec are the crystals you use? I looked at Farnell, RS, Rapid, Mouser and Digi-Key. Only Digi-Key have non-SMD in stock - all the others only have them with much higher load capacitance.

No particular spec. Just generic 27MHz fundamental-mode crystals.

I stopped believing in adding capacitors to crystals a few years back. The Ultimate3S kit still has pads for the originally supplied 22pF capacitors but they are no longer supplied or recommended. It was found that sometimes the 20MHz crystal wouldn't oscillate with the capacitors in place. But it always oscillates without them. So on the principles of the guy who designed TVs in ye olde days and used to remove one component at a time until it stopped working... same theory, I stopped putting capacitors in the circuit.

The fact the 27MHz Si5351A crystal tends to oscillate around 27.004 and the 20MHz Atmel AVR crystal at around 20.006MHz... indicates ideally a bit of capacitance would be needed. But stray PCB capacitance etc is enough to make sure everything always works, and we don't need them to be precisely on frequency either. 

One way to have trimmed the reference oscillator would be a trimmer capacitor on one side of the crystal, commonly seen. But we just do it in software... as long as the software knows the oscillation frequency it just takes it into account when calculating Si5351A values and everything comes out on frequency. It saves physical parts (the trimmer capacitor) and it also means you can employ a GPS to let the software accurately measure the actual oscillation frequency itself. Just perfect all round.

So just buy any 27MHz crystal and proceed regardless. Do make sure it is a fundamental mode one though not 3rd harmonic type.

4. I now understand why level shifters are not needed - I will remove them from my project. The outputs are open-collector as it requires wired AND so, as long as the pull-ups are to the lower voltage, it is safe. The only consideration is if the lower logic levels are OK for the higher voltage device. I have a feeling there are a very large number of unnecessary I2C level shifters in the world. As long as I am in control of the hardware design I can guarantee there are no pull-ups to 5V.

Hahaha I like that thought, but the large number of unnecessary I2C level shifters in the world! I'd add, a lot of other logic level shifters also unnecessary. It's important not to design recklessly but it sometimes seems there's a tendency to be too conservative!

73 Hans G0UPL 


Re: QCX CW transceiver

John VA7JBE
 

What I did on my T1 was to leave the tails end of all the wires at different lengths, going from longer to shorter in a clockwise direction.  That way I was able to insert one or two wires at a time, pull them through, and then move on to the next pair without having to worry about running out of space or getting the wires mixed up.  I got the idea from Hans' method of building the 50-ohm Dummy Load kit.  If there's ever an update to the QCX manual, it might be worth including this method.

You can find a better illustrated explanation here, starting at step 3.5  https://qrp-labs.com/images/dummyload/dummyload.pdf

Cheers,
John VA7JBE


Re: No GPS data with U3S - For Hans

Brian Summers
 

Strange, I sent this several hours ago but it never appeared. Let me try again.

Brian VE7JKZ



-------- Forwarded Message --------
Subject: Re: [QRPLabs] No GPS data with U3S - For Hans
Date: Thu, 6 Dec 2018 09:32:23 -0800
From: Brian Summers <ve7jkz@...>
Reply-To: QRPLabs@groups.io
To: QRPLabs@groups.io


I've managed to come up with a procedure for repeating my problem. I've got the unit mode indices programmed so it operates as follows:

1. Power on U3S. Ultimate3S 3.12a appears. Then the display switches to GPS data as it should.

2. Press the Menu button once and the display reads:

0]-0-000,473,000
TX CW-------00-0

3. Press the menu button again and the displays reads:

1]-0-000,473,000
TX CW-------00-0

4. All the above really shows is that I have the same message in mode index 0 and 1. Not intentionally I might add. I'm new to the U3S so this is all happenstance.

5. Now power off/on. Once again the Ultimate3S screen appears followed by GPS data.

6. Press the menu button once and see the display as para 2 above.

7. Now press the edit button twice to enable. The display will show:

0] 0 000,473,000
TX CW       00 0

8. Power off/on. The Ultimate 3S screen appears, the GPS data does not appear and instead the display shows as follows. The beating heart appears where it should.

0] 0 000,473,000
TX CW

9. Press the menu button again and see:

0] 0 000,473,000
TX CW       00 0

10. Press the menu button again and see:

1]-0-000,473,000
TX CW-------00 0

11. You can see from 8 and 9 that I've created two messages identified with mode index 0]. Now you can repeat from para 8. The unit goes directly from the Ultimate 3S screen to the first mode setting every time, bypassing the GPS data screen. It all repeats.

12. To recover from this situation power off/on as para 8, go to the screen shown in para 9, then press the edit button twice to disable the mode setting. Now power off/on and GPS data will follow the Ultimate 3S screen.

Doubtless there are other ways of demonstrating this but the above is repeatable for me. Here's hoping that when I post this the formatting does not change........

Brian VE7JKZ



On 11/30/2018 8:34 AM, Brian Summers wrote:
GM Alan,

For the record my notes show the following when trying to set up for 473Khz.

0] 0 000,473,000 then on the line below, TX CW.  Call this message A

now press the menu key and the display shows:

0] 0 000,473,000 then on the line below, TX CW      00 0.  Call this message B.

Under these conditions there is no GPS data. Now disable message B, switch off/on, then GPS data appears immediately following the Ultimate 3S information screen.

I suppose I could spend more time on this trying other modes and messages but it can be very time consuming particularly with the case mounted push button switches which I find to be very flimsy and troublesome. For now I'm content to know that if I have no GPS data and scroll the menu to find two messages with the same number, I know what to do about it.

73 Brian VE7JKZ


On 11/30/2018 2:42 AM, Alan G4ZFQ wrote:
Strange thing is, no error message appears.

 Brian,

I guess if Hans knew it would happen there would be no error message because he had put it right!

>when two almost identical modes are set with the same band number

Maybe let Hans know exactly what settings, what are "almost identical" modes?

73 Alan G4ZFQ