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Gerald Ball
 

I would like to send messages to this group. regards gerry


--
gerry


Re: ProgRock not working #progrock

Hans Summers
 

Hi Robin

If you have an inverter in there as well... then that's also a problem :-/     The leading edge of the 1pps from the GPS is the one that is considered accurate. There's no guarantee about the trailing edge. 

If there was a latency that was fixed precisely, then all would be well. But if you have Resistors and Capacitors in there that are generating the stretching, and triggering off the wrong edges... then all bets are off.... 

I suspect that when you get your QLG1 you will find all works as expected. 

73 Hans G0UPL

On Thu, Jul 18, 2019 at 6:24 PM Robin Midgett <K4IDC@...> wrote:
Hi Hans,
Do you mean like this? :>)
This morning the error at 16.686600 MHz was 14 Hz. In other words, I set register 8 to 16,686,614 to obtain a measured output of 16,686,600. Doubling that output frequency resulted in a doubling of the error, doubling again, same error factor. Then I set about measuring the latency...probe 1 is the output of the level shifter/inverter stage that is connected to the input of the 555. Probe 2 is the 555 output.



Now....what to do about it? Perhaps a pulse stretcher with a Schmitt trigger input? 
I'm more of an analog guy, so this experience is really helping me learn. This is fun!
Thank you, Hans! 
Thanks,
Robin Midgett K4IDC


On Wed, Jul 17, 2019 at 10:40 PM Hans Summers <hans.summers@...> wrote:
Hi Robin

Is there a possibility your 555 pulse extender circuit could also be adding variable latency to the pulse? It would not take very much error... bear in mind, every 1us is 1 part-per-million error at the output. 

Anyway it will be interesting to see how things go once you get your QLG1

73 Hans G0UPL

On Thu, Jul 18, 2019 at 12:44 AM Robin Midgett <K4IDC@...> wrote:
Hi Hans,
Thanks for the response.
I'd really like to understand what's causing this issue & what to do about it.
Presently I have the Trimble GPS 1PPS 2.8V logic 1mS pulse driving a level shifter to a 5V logic level and also providing the needed inversion for driving a non-retriggerable 555 one shot. The 555 is giving a 112mS long positive going 5volt pulse for every 1PPS from the Trimble GPS. I'm applying the 112mS pulse to the GPS input on the ProgRock. In this configuration, register 2 is being updated to a value that causes the output frequency to run low of the desired by ~18 Hz.
If I remove the 1PPS, ground the 1PPS input on the ProgRock & reboot the ProgRock, then manually dial in register 2 to give the proper output frequency, it'll stay there within a couple of Hz. over a period of many hours if not days, thermal effects not withstanding.
It seems to me that under GPS discipline the frequency of the crystal is being mis-read, or there's some magic in register 28 that needs to be adjusted; these are my guesses at this point.

My primary reason for the 555 is to allow me the opportunity to experiment with different pulse widths. Since the QLG1 gives 100ms, I started with a value near that. I can trim it to be spot on later, but 112mS is where my particular RC value came to land late last night. I know from experience that 1mS doesn't work, nor does 11mS, at least not as my ProgRock sits currently.

My QLG1 and the OCXO from QRPLabs are in the mail. Once I have those we can see if anything changes. If you have any further suggestions, I'm all ears.

Thanks,
Robin Midgett K4IDC


On Mon, Jul 15, 2019 at 3:33 PM Hans Summers <hans.summers@...> wrote:
Hi Robin, Graham, Sid, all

There have been a lot of posts on this topic and being on vacation at the moment I kind of lost track of where this got to.

ProgRock should work as advertised on the web page and documentation. If it doesn't, something is wrong. 

A GPS disciplined ProgRock should be accurate well within 0.05ppm (note that this parts-per-million specification means that the absolute precision in Hz, scales with frequency). This is what I have seen in all my tests and has been verified by other constructors too. To get the system working does require:

1. GPS correction threshold register must he understood properly. To get maximum precision requires setting the GPS correction threshold register to zero (default is 5Hz). 

2. The 1pps signal needs to be at 5V logic level. Many GPS units have 2.8V logic level outputs and need level conversion. This can be done with pull-up resistors with some care and some inevitable degradation in noise immunity. Or with proper level conversion.

3. The GPS pulse needs to be long enough for the processor to handle it properly. I'm not actually sure what the minimum is. Many common modern GPS modules have 0.1 second positive pulses, these work fine. Some modules with very short pulses e.g. 1 microsecond wouldn't work.

Note that the QRP Labs QLG1 GPS kit http://qrp-labs.com/qlg1 was used in all my testing and works very well. It has 0.1 second positive pulse and it has proper logic level conversion. The QLG1 has a very accurate 1pps specified with max 11 nanosecond r.m.s error.

If the ProgRock isn't performing as expected then something is wrong. That could be an electrical problem (soldering problem, dead component etc); or some issue with the characteristics of the 1 pulse-per-second signal input. 

If there's any question I haven't covered here, please let me know.

73 Hans G0UPL 







On Mon, Jul 15, 2019, 16:31 Robin Midgett <K4IDC@...> wrote:
Hi Graham & the group,
The issue Sid & I and possibly others who aren't reading the mail on this subject isn't about stability with the TCXO or OCXO. The stability with those optional oscillators is well documented and not in question, and for a broad range of applications, mine included, well more than sufficient.
The issue here is making the ProgRock work reliably with GPS discipline, and why that isn't happening reliably.
Diatribes about the NEED for GPS discipline in anyone's application are irrelevant simply because the fact is the product doesn't perform reliably as advertised with GPS discipline, and, very importantly, within the context of kit building and the price of the kit, this is not a deal breaker or terribly surprising. This is part of the value of kit building; the builder has the opportunity to improve the kit as they see fit, or not.
What is perhaps more interesting and worth studying is why the GPS discipline isn't as reliable as it should be, and what's to be done to mitigate that deficiency. Based on the current responses to our (Sid & my) posts, Hans may be the only person qualified to really answer the questions regarding the apparent deficiency.
Further, personal attacks are not helpful, Andy Brilleaux. Let's leave those for the elementary school playground. Let's approach this issue scientifically and see if a successful solution can be had. I suspect it can and will.
Thanks,
Robin Midgett K4IDC


On Sun, Jul 14, 2019 at 3:15 PM Graham W <gram.warrington@...> wrote:
I have built a few prog rocks. I did not use the 27 mhz crystal as supplied, but installed a TCXO as suggested in the manual. I find ,even without GPS control that it is very stable. The pads are already there for the TCXO.
Graham VE3WGW


Re: i was dreaming

Mike
 

On 18 Jul 2019 at 14:09, Mike wrote:

I was dreaming in morse last night. The other station was sending quite
badly
and I was trying to hear him through the qrm on 40m. I thought he was sending
GDAD, GD1D with cw abbreviations for the 1, but he kept repeating his
callsign
over and over again. In the end I gave up and in my dream qsy'ed somewhere
else.
When I woke up The cw was clear in my mind, he was sending QSX.
No wonder I did'nt get it.....
QSX was just a dream..................


Re: QCX components needed for latest hardware revision.

Stephen Thompson <sgthompson512@...>
 

Thank you all for your suggestions.  I'm sure now I'll find what I need to complete this QCX hardware update.

73
Steve
K5PK


Re: QCX components needed for latest hardware revision.

Chris Hoffman
 

I also upgraded my QCX unit as I was building it. 

I was able to order individual components from Digikey.com.  You just have to search through a large catalog of components. 

Chris Hoffman
WA2SEM


Re: i was dreaming

Jeff Dixon
 

I wasn't on 40 last night!


Re: Help ! My U3S behaves badly.... #u3s

PA3CRZ
 

Thanks guys, for all the answers.

I disconnected the external buttons, and now the U3S starts up with "Diagnostic".
After pressing the button on the PCB, the splash screen appears, and I can further configure the device.
So, it does seem that the pin 25 button was shorted to ground. However, measuring the button without it
being connected to the PCB there is no shortcircuit (only when I press the button, of course......).

So, I'm still not sure why this happens.
Will investigate further. For now, the U3S is usable again. I just can't configure it using the external buttons...

Thanks, 73
Hans


Re: QCX components needed for latest hardware revision.

Jack Brabham - KZ5A
 

Try Mouser.com, they ship from Mansfield, TX you'll probably receive your parts in 2 days.

73 Jack KZ5A

On 7/17/2019 10:29 PM, Stephen Thompson wrote:
I'd like to perform the post April 12 revisions; to (CW shaping) and the (R24 phase shift adjustment range fix) to my QCX. I live in Austin, TX and am striking out on finding a source of non bulk component parts. Fry's electronics was no help at all. All I need are a couple of resistors and a capacitor to complete this hardware update. Would anyone here know of a good source for us hobbyists.

73 de K5PK
Steve



Re: ProgRock not working #progrock

Robin Midgett
 

Hi Hans,
Do you mean like this? :>)
This morning the error at 16.686600 MHz was 14 Hz. In other words, I set register 8 to 16,686,614 to obtain a measured output of 16,686,600. Doubling that output frequency resulted in a doubling of the error, doubling again, same error factor. Then I set about measuring the latency...probe 1 is the output of the level shifter/inverter stage that is connected to the input of the 555. Probe 2 is the 555 output.



Now....what to do about it? Perhaps a pulse stretcher with a Schmitt trigger input? 
I'm more of an analog guy, so this experience is really helping me learn. This is fun!
Thank you, Hans! 
Thanks,
Robin Midgett K4IDC


On Wed, Jul 17, 2019 at 10:40 PM Hans Summers <hans.summers@...> wrote:
Hi Robin

Is there a possibility your 555 pulse extender circuit could also be adding variable latency to the pulse? It would not take very much error... bear in mind, every 1us is 1 part-per-million error at the output. 

Anyway it will be interesting to see how things go once you get your QLG1

73 Hans G0UPL

On Thu, Jul 18, 2019 at 12:44 AM Robin Midgett <K4IDC@...> wrote:
Hi Hans,
Thanks for the response.
I'd really like to understand what's causing this issue & what to do about it.
Presently I have the Trimble GPS 1PPS 2.8V logic 1mS pulse driving a level shifter to a 5V logic level and also providing the needed inversion for driving a non-retriggerable 555 one shot. The 555 is giving a 112mS long positive going 5volt pulse for every 1PPS from the Trimble GPS. I'm applying the 112mS pulse to the GPS input on the ProgRock. In this configuration, register 2 is being updated to a value that causes the output frequency to run low of the desired by ~18 Hz.
If I remove the 1PPS, ground the 1PPS input on the ProgRock & reboot the ProgRock, then manually dial in register 2 to give the proper output frequency, it'll stay there within a couple of Hz. over a period of many hours if not days, thermal effects not withstanding.
It seems to me that under GPS discipline the frequency of the crystal is being mis-read, or there's some magic in register 28 that needs to be adjusted; these are my guesses at this point.

My primary reason for the 555 is to allow me the opportunity to experiment with different pulse widths. Since the QLG1 gives 100ms, I started with a value near that. I can trim it to be spot on later, but 112mS is where my particular RC value came to land late last night. I know from experience that 1mS doesn't work, nor does 11mS, at least not as my ProgRock sits currently.

My QLG1 and the OCXO from QRPLabs are in the mail. Once I have those we can see if anything changes. If you have any further suggestions, I'm all ears.

Thanks,
Robin Midgett K4IDC


On Mon, Jul 15, 2019 at 3:33 PM Hans Summers <hans.summers@...> wrote:
Hi Robin, Graham, Sid, all

There have been a lot of posts on this topic and being on vacation at the moment I kind of lost track of where this got to.

ProgRock should work as advertised on the web page and documentation. If it doesn't, something is wrong. 

A GPS disciplined ProgRock should be accurate well within 0.05ppm (note that this parts-per-million specification means that the absolute precision in Hz, scales with frequency). This is what I have seen in all my tests and has been verified by other constructors too. To get the system working does require:

1. GPS correction threshold register must he understood properly. To get maximum precision requires setting the GPS correction threshold register to zero (default is 5Hz). 

2. The 1pps signal needs to be at 5V logic level. Many GPS units have 2.8V logic level outputs and need level conversion. This can be done with pull-up resistors with some care and some inevitable degradation in noise immunity. Or with proper level conversion.

3. The GPS pulse needs to be long enough for the processor to handle it properly. I'm not actually sure what the minimum is. Many common modern GPS modules have 0.1 second positive pulses, these work fine. Some modules with very short pulses e.g. 1 microsecond wouldn't work.

Note that the QRP Labs QLG1 GPS kit http://qrp-labs.com/qlg1 was used in all my testing and works very well. It has 0.1 second positive pulse and it has proper logic level conversion. The QLG1 has a very accurate 1pps specified with max 11 nanosecond r.m.s error.

If the ProgRock isn't performing as expected then something is wrong. That could be an electrical problem (soldering problem, dead component etc); or some issue with the characteristics of the 1 pulse-per-second signal input. 

If there's any question I haven't covered here, please let me know.

73 Hans G0UPL 







On Mon, Jul 15, 2019, 16:31 Robin Midgett <K4IDC@...> wrote:
Hi Graham & the group,
The issue Sid & I and possibly others who aren't reading the mail on this subject isn't about stability with the TCXO or OCXO. The stability with those optional oscillators is well documented and not in question, and for a broad range of applications, mine included, well more than sufficient.
The issue here is making the ProgRock work reliably with GPS discipline, and why that isn't happening reliably.
Diatribes about the NEED for GPS discipline in anyone's application are irrelevant simply because the fact is the product doesn't perform reliably as advertised with GPS discipline, and, very importantly, within the context of kit building and the price of the kit, this is not a deal breaker or terribly surprising. This is part of the value of kit building; the builder has the opportunity to improve the kit as they see fit, or not.
What is perhaps more interesting and worth studying is why the GPS discipline isn't as reliable as it should be, and what's to be done to mitigate that deficiency. Based on the current responses to our (Sid & my) posts, Hans may be the only person qualified to really answer the questions regarding the apparent deficiency.
Further, personal attacks are not helpful, Andy Brilleaux. Let's leave those for the elementary school playground. Let's approach this issue scientifically and see if a successful solution can be had. I suspect it can and will.
Thanks,
Robin Midgett K4IDC


On Sun, Jul 14, 2019 at 3:15 PM Graham W <gram.warrington@...> wrote:
I have built a few prog rocks. I did not use the 27 mhz crystal as supplied, but installed a TCXO as suggested in the manual. I find ,even without GPS control that it is very stable. The pads are already there for the TCXO.
Graham VE3WGW


Re: i was dreaming

Garry48
 

Mike,

 

Was your dream in color? 😊

 

Garry

 

Sent from Mail for Windows 10

 

From: Mike
Sent: Thursday, July 18, 2019 6:09 AM
To: QRPLabs@groups.io
Subject: [QRPLabs] i was dreaming

 

I  was dreaming in morse last night. The other station was sending quite badly

and I was trying to hear him through the qrm on 40m. I thought he was sending

GDAD, GD1D with cw abbreviations for the 1, but he kept repeating his callsign

over and over again. In the end I gave up and in my dream qsy'ed somewhere

else.

When I woke up The cw was clear in my mind, he was sending QSX.

No wonder I did'nt get it.....

<vbg>

 

 

 


Re: QCX components needed for latest hardware revision.

Greg Walters
 

I'm also a Tayda, Digi-Key, and Mouser user. Usually vary between them based on the item I'm seeking. You can't really beat the prices on Tayda, but they don't have as an extensive inventory selection as Mouser or Digi-Key. 

There's my two cents. 
--
73,
Greg
KY4GW


i was dreaming

Mike
 

I was dreaming in morse last night. The other station was sending quite badly
and I was trying to hear him through the qrm on 40m. I thought he was sending
GDAD, GD1D with cw abbreviations for the 1, but he kept repeating his callsign
over and over again. In the end I gave up and in my dream qsy'ed somewhere
else.
When I woke up The cw was clear in my mind, he was sending QSX.
No wonder I did'nt get it.....
<vbg>


Re: QCX components needed for latest hardware revision.

jjpurdum
 

I think, at one time or another, I've probably used most of the well-known vendors (Digikey, Mouser, Arrow, etc.). Tayda Electronics' prices are tough to beat and I have yet to get a "bad" part from them. Also, they have a distribution facility in CO, so shipping time is usually pretty good. (If you order a non-stocked part, it comes from Thailand which lengths the shipping period.) While I now tend to use with the "North America only" checkbox on eBay, foreign vendors have caught on and it seems that many are using PO Boxes with US addresses so they appear to be domestic. Most vendors, however, know that if they advertise a "arrive by" date in their ads and it's much later than that, eBay issues them a nastygram to correct it or lose their listing. Just pay attention to the "arrive by" date.

Jack, W8TEE

On Thursday, July 18, 2019, 12:36:57 AM EDT, Stephen Thompson <sgthompson512@...> wrote:


I'd like to perform the post April 12 revisions; to (CW shaping) and the (R24 phase shift adjustment range fix) to my QCX. I live in Austin, TX and am striking out on finding a source of non bulk component parts. Fry's electronics was no help at all. All I need are a couple of resistors and a capacitor to complete this hardware update. Would anyone here know of a good source for us hobbyists.

73 de K5PK
Steve


Re: QCX components needed for latest hardware revision.

K2DB Paul Mackanos
 

Digikey 

On Thu, Jul 18, 2019 at 12:36 AM Stephen Thompson <sgthompson512@...> wrote:
I'd like to perform the post April 12 revisions; to (CW shaping) and the (R24 phase shift adjustment range fix) to my QCX. I live in Austin, TX and am striking out on finding a source of non bulk component parts. Fry's electronics was no help at all. All I need are a couple of resistors and a capacitor to complete this hardware update. Would anyone here know of a good source for us hobbyists.

73 de K5PK
Steve


Re: QCX components needed for latest hardware revision.

Bob Benedict, KD8CGH
 

I have also used Tayda as well as the traditional Digi-Key and Mouser.


Re: wspr on qcx #qcx

Peter GM0EUL
 

Hi Terry
Yes, but you have to modify it slightly as shown here:

https://www.qrp-labs.com/qcx/qcxmods/qcxwspr.html

Cheers
Peter GM0EUL


Re: wspr on qcx #qcx

Alan de G1FXB
 

Use of the groups search function reveals at least one thread
on how to deal with the AF filter.
https://groups.io/g/QRPLabs/topic/29710692#31294

One published solution is:-
http://qrp-labs.com/qcx/qcxmods/qcxwspr.html
another is to use the raw RX IQ signals if chosen S/W allows.


Alan

On 18/07/2019 09:38, terryhugheskirkcudbrifght via Groups.Io wrote:
i know that the qcx will transmit wspr but can anybody tell me it can receive wspr sigs

terry gm4dso


wspr on qcx #qcx

terryhugheskirkcudbrifght@...
 

i know that the qcx will transmit wspr but can anybody tell me it can receive wspr sigs

terry gm4dso


Re: QCX components needed for latest hardware revision.

SkipF, NT1G <skip.flem@...>
 

I use www.taydaelectronics.com
 And get the parts in a week.
73 de SkipF, NT1G


On Thu, Jul 18, 2019, 12:36 AM Stephen Thompson <sgthompson512@...> wrote:
I'd like to perform the post April 12 revisions; to (CW shaping) and the (R24 phase shift adjustment range fix) to my QCX. I live in Austin, TX and am striking out on finding a source of non bulk component parts. Fry's electronics was no help at all. All I need are a couple of resistors and a capacitor to complete this hardware update. Would anyone here know of a good source for us hobbyists.

73 de K5PK
Steve


Re: QCX components needed for latest hardware revision.

Peter GM0EUL
 

Hi Steve
I've had stuff from eBay and Amazon, try there if you haven't already.  If it's just a couple of resistors and a capacitor I'd be happy to give them to you (if I have them, what values do you need?) but I live in Scotland, still the offer's there for the price of the postage.

73
Peter GM0EUL