Just found out by reading QCX mail that I have wound the three small winding's on T1 with only 3 turns instead of 5 per the instructions! However rig is putting out 4 watts and receiver is great! WHY? Glen N8WE
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Re: QCX audio crackle is still there!
Just in case anyone stumbles over this.? I recently had to replace the QCX Atmega chip; this after bricking the original.? I've since learned how to update the chips properly. Initially I thought that audio crackle had been solved with the new chip and firmware, but it has not.
The audio crackle is like hearing lightening strikes while listening to HF DX. I can hear CW and WSPR tones but, really, the crackle is so harsh it makes using the 30 metre QCX? unpleasant.
So, I';m open for suggestions as to how to resolve the issue.
I'm using a 12 volt, fully charged battery, to drive the radio.
Thanks
Barry
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Keith... I sure apologize for taking this long to respond.? After you mentioned Earl's web page, I had a look and simply sent him a note.? He had the parts to me in jig time!? In fact I recently needed a couple of 1/2 watt resistors... he happened to be coming in to Sudbury, so I met up with him and made the exchange.? That web page is huge.
Thanks for that suggestion.
Barry
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Not sure why they picked the 20M version. I plan to use the 20M in the trailer when we are camping (often). We spent a week on Salt Spring this summer and enjoyed it so much we will be back again this year. I plan on using a "Buddie Pole" with the 20M QCX and see how it works out.
I'm going to put the rig in a Hammond project box that has a sloping front panel and will be mounting the LCD, pots and switches on the front panel (aluminum) and all the jacks on the front and back panels (plastic).
I use some "play dough" that i get at the dollar store to hold the small components for soldering and it seems to work well for me. I have used small pieces of masking tape before but the play dough seems to work better. Rick VE7TK is also building one and he has a lot of experience with winding toroids so we are going to have him give as a quick presentation when we get to that point. Should be a fun project and I am going to take lots of pictures !!
Hope you have a Merry Christmas and all the best in 2018. Will keep you advised how things are going.
73 - Hew
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On 2017-12-07 6:55 PM, Keith VE7GDH wrote: Hew VA7HU wrote...
About 6 of us in the local club are building the 20M
version as a club project. Mine are for 80M and 40M, so I won't have a QCX there,
but I could dial my "big rig" down to 5W. We might be
a bit close for 20M though. Of course, that's assuming
you can send slow enough for me!
Just a suggestion... I found it tricky soldering the
single pin headers in place. If I was doing it again,
I would probably install them right at the beginning
when they weren't surrounded by other parts. Sticking
the pin in some dense foam might be a way of holding
it upright while putting the PCB down over the pin to
solder it.
I put the male pin header on the LCD display instead
of the female connector (a la BITX) so I soldered the
female connector on the QCX board. The stand-offs are
a bit long. You would think I would have learned from
the first one, but if there's a third, I'll sand about
1 mm off the stand-offs before adding the LCD display.
That way, the header can just be pushed flush down
onto the LCD display for soldering. With the stand-offs
a bit long, I ended up pushing the pins a bit further
through the plastic part of the header, so the short
pins made it only just to the top of the LCD circuit.
I used the LCD circuit board to push the male pins
down into the connector and then soldered them.
Good luck with the club project!
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Re: QCX Troubleshooting - Please can you help?
AVCC should be very close to the Vcc supply voltage.? If that is at 4.6 then either your Vcc is at
4.6 or something is dragging AVCC down.? Normally this pin is unconnected, but if you want
best repeat measurements from the ADC you can add a filter to the AVCC lead.
ADC reference for analog-to-digital voltage conversions is the built in 1.2 volt AREF potential.
If the AREF is not correct then the ADC measurements will be inaccurate.
If using ADC inputs to detect specific voltages you can use a high impedance DC meter
to measure the actual voltage to see if they are within a range specified by the software.
Arv
_._
On Sat, Dec 9, 2017 at 10:23 AM, <ondrej.briatka@...> wrote: Problem with encoder - try to check voltage at pin AVCC of ATmega. It should be close to 5V.
After "Unreliable microcontroller start-up" modification, I had only 4,6V on AVCC that caused bad decoding of buttons inputs (3 buttons + resistors make a different voltages on A/D input, software compares it to reference AVCC).
Inductors 100uH has quite high resistance of 7 ohm that means voltage drop on ATmega pins.
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Re: Two-band QCX (20 and 17m), is it possible?
Thanks Alvey, this is very useful info. I was also thinking abt the "preselector" for the front-end ;) glad to learn from Hans that he is willing to modify the software :)?
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Re: Two-band QCX (20 and 17m), is it possible?
I get the point Hans and makes sense. But... tinkerers always pushing the envelope :) I was considering 17 and 20 taking into account the monoband ethos of the QCX because these bands are close. What I do not know is if this "stretch" is within the correct quadrature limits. The idea? would be 20m the primary band and 17m the secondary.
Thanks for producing things like these for us to enjoy!
73? de antonio, EA4LE?
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Re: QCX Troubleshooting - Please can you help?
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Re: QCX Troubleshooting - Please can you help?
Problem with encoder - try to check voltage at pin AVCC of ATmega. It should be close to 5V.
After "Unreliable microcontroller start-up" modification, I had only 4,6V on AVCC that caused bad decoding of buttons inputs (3 buttons + resistors make a different voltages on A/D input, software compares it to reference AVCC).
Inductors 100uH has quite high resistance of 7 ohm that means voltage drop on ATmega pins.
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check your resistor value
Hi,
Building the U3s with 5w amp, no rf output so stripped the amp out of system and base U3s works.
The 5w amp biased up ok but still no output so I checked the resistor placement with a Dvm, R2 is 15k and feeds the base and collector of Q3 and base of Q4, R19 is also 15k, both resistors have identical colour bands, however, one, R2 measures 10k!
There are no 10k resistors in this kit.?
End result is a blown Q3.
Andy
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Dear QRPLabs Members, ? In my last message I invited all QRSS and WSPR stations to join the Las Cruces QRSS Mafia to operate with us on New Year¡¯s Eve.?? Well, today is December 9th and we have about 21 days left to get our stuff ready to operate from 0000Z 31 December to 2400 1 January 2018.?? It is 48 hours and the purpose is to Celebrate the forward movement of the Amateur Radio QRSS Operation by filling all the Grabber stations with signals.?? The more signals the better.? Don¡¯t worry about stepping on each other a little bit.? Just get a signal in there wherever you can.?? Mother Nature¡¯s Propagation will scramble it even worse, so it won¡¯t really matter.??? Some collisions of signals at one grabber will not be perceivable at another.? So in the end it doesn¡¯t matter.?? What really matters is that you got on the air and you contributed to the massive whiteout of the grabber.? There is a way for the WSPR crowd to join us by programming their U3S¡¯s to do both WSPR and the rest of the 10 minute give QRSS some time with another 2 DFCW QRSS signal and still put a WSPR transmission out every 10 Minutes.??? So get your program manual out and try something new.? We would also love to see you call sign on our screens. ? My contribution this year as a multi-band grabber in New Mexico.? It is presently operating on 30M and 40M? 24/7 in the test mode.? (I may have to take it down for some additional tweaks to improve its operation) but for the most part it will be up. Between now and New Year¡¯s Eve, I plan to add 80M and 20M to it and have them operational.? The Website is ?and this is my test bed for building an all Amateur Radio Band Grabber for 2200M through 10M grabber at This location? by next New Year¡¯s Eve.? Each grabber band consists of a QRPLabs QCX transceiver operating as a receiver, a raspberry pi 3B operating as a spectrum analyzer, and a usb sound card of the inexpensive variety.? It is working well and I am learning lots of new things about it as I keep peeling the onion.? But the one thing I do know for sure.? An inexpensive quality QRSS grabber is within reach for anyone who wants to experiment with these units.? ? If anyone would like to know more about my ¡°experiment¡± let me know.?? Go to the website and look at my grabs.? Start planning your own setup.? ? Take care and have fun.?? See you on New Year¡¯s Eve.? Get your ?QRSS TRANSMITTERS ready to go on the air.? New Year¡¯s Eve will be here before you know it.? (In case you have forgotten, New Year¡¯s Eve comes right after that jolly old man called Santa Claus or Saint Nicholas or whatever he is called in your country,? and right after New Year¡¯s day come the credit card bills for all the new radio equipment you bought. ) ? Take care and have fun.? Hope to see you on my new Grabber.? QRSS is a BLAST, even at mW¡¯s Merry Christmas, 73 Dave Hassall WA5DJJ? Las Cruces, New Mexico Website: http://www.zianet.com/dhassall/ ?
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Re: ZL1RS balloon flight - BB01
Would be quite interested in the info too
John
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On 12/9/2017 7:54 AM, Don Meyerhoff wrote: Very cool Bob. If you have some info on it I would like to work on something similar with my kid to get her interested in the hobby.
73
Don Meyerhoff
WA2SWX
On Dec 8, 2017 4:40 PM, "Bob Sutton via Groups.Io" <zl1rs@... <mailto:[email protected]>> wrote:
Up and flying ... U3S firmware and QRP-Labs synth board (modified
and trimmed down! ... see pix). 10mW into a 20m dipole. Four 52 x
19mm solar cells, 3V3 boost regulator, no battery.
Tracking at
!mt=roadmap&mz=5&qm=3_days&mc=-36.74043,172.26232&f=BB01&q=BB01
<!mt=roadmap&mz=5&qm=3_days&mc=-36.74043,172.26232&f=BB01&q=BB01>
More info will appear on the QRP-Labs website in the 'Flights'
section when Hans has time.
73, Bob? ZL1RS
3V3 boost regulator ? - ? GP-02 GPS?? - ? ATmega328P-AU ? -?? TMP36
temperature sensor?? -?? QRP-Labs synth board with TCXO
90cm 'clear balloon' (same as U3B-12 is currently flying under)
Hydrogen gas, inflated to provide 3.5 to 4 grams of 'free lift'
--
III
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Re: ZL1RS balloon flight - BB01
Looking good Bob...lots of sunlight to play with there :)
Going to be an interesting flight.
Jim,N2NXZ
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Thanks Hans and Hajo. I was coming at it from a different angle. Some time ago, I used the WSPRcode.exe utility from the WSPR website to convert fixed TX messages into the required tone sequences. Then knowing the sequence, frequencies and duration of the tones, it was possible to write a PIC-based program in assembler ?to generate WSPR beacon signals with an SI570. I was wondering if it was possible to obtain similar information for FT8 TX messages. (Only TX - not RX).
73
Brian
G3ZOH
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Re: ZL1RS balloon flight - BB01
Very cool Bob. If you have some info on it I would like to work on something similar with my kid to get her interested in the hobby.? 73
Don Meyerhoff
WA2SWX
On Dec 8, 2017 4:40 PM, "Bob Sutton via Groups.Io" <zl1rs= [email protected]> wrote:
Up and flying ... U3S firmware and QRP-Labs synth board (modified
and trimmed down! ... see pix). 10mW into a 20m dipole. Four 52 x
19mm solar cells, 3V3 boost regulator, no battery.
Tracking at
More info will appear on the QRP-Labs website in the 'Flights'
section when Hans has time.
73, Bob? ZL1RS
3V3 boost regulator ? - ? GP-02 GPS?? - ? ATmega328P-AU ? -?? TMP36
temperature sensor?? -?? QRP-Labs synth board with TCXO
90cm 'clear balloon' (same as U3B-12 is currently flying under)
Hydrogen gas, inflated to provide 3.5 to 4 grams of 'free lift'
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P.S... another tip...?
Don't believe the websites which quote K1JT saying the tone spacing is 12000 / 2048. And symbol duration is the inverse of that. No... Believe the websites which quote K1JT saying 12000 / 1920. Even though the latter (correct) websites are less numerous... another mystery.
On Dec 9, 2017 3:34 PM, "QRP Labs" < hans.summers@...> wrote: And good luck... hoping that you know: 1) C language 2) Fortran language 3) how to disentangle a large pile of spaghetti?
I'm still working on at least 2 out of 3 of these...? ?:-/
73 Hans G0UPL? ?
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And good luck... hoping that you know: 1) C language 2) Fortran language 3) how to disentangle a large pile of spaghetti?
I'm still working on at least 2 out of 3 of these...? ?:-/
73 Hans G0UPL? ?
On Dec 9, 2017 3:32 PM, "Hajo Dezelski" < dl1sdz@...> wrote: Hi Brian,
grab the source code at the bottom of the page:?
73 de Hajo DL1SDZ
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Hi Brian,
grab the source code at the bottom of the page:?
73 de Hajo DL1SDZ
On Sat, Dec 9, 2017 at 1:22 PM, Brian George via Groups.Io <george.familyuk@...> wrote: Hi all, This is a bit off topic as Hans does such a fantastic job with his QRPLabs products but .....does anyone know where to find information on the FT8 protocol in sufficient detail to serve as a basis for programming FT8 TX messages ??
Thanks
Brian
G3ZOH?
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Hi all, This is a bit off topic as Hans does such a fantastic job with his QRPLabs products but .....does anyone know where to find information on the FT8 protocol in sufficient detail to serve as a basis for programming FT8 TX messages ??
Thanks
Brian
G3ZOH?
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Re: Assembly manual Rev 1.08
Hi Des?
Yes I think it is possible. If the I-Q pot has to compensate for usual amplitude imbalances but additionally has the trauma of having to deal with the additional imbalance caused by the R19/R25 reversal then it could run out of trimmer adjustment range. I think it's quite possible.?
Still, if your unwanted sideband is already excellent I think I'd be inclined to leave it as is!
73 Hans G0UPL? ?
On Dec 9, 2017 1:56 PM, "QRP_nut" < raspiham1973@...> wrote: Hi Hans and thanks for swift the reply,
Would R19 & R25 being reversed on the PCB possibly cause one of the I/Q trim-pots to run out of adjustment while setting-up the I/Q balance? I just checked my QCX80 and R19 & R25 are reversed.
While setting-up the I/Q balance I found one of the two pots' (dont remember which one but probably R27) ran out of adjustment and became "one ended" though image rejection by this time was allready excellent so I left it as it was.
But looking at the schematic again in light of the revalation regarding R19 & R25 it would seem that those two resistors being reversed in position might account for one of the adjustment pots being at the end of its adjustment range?
73,s
Des (M0AYF)
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Antonio Fernandez EA4LE
M0RON
Hajo Dezelski