Hmmm.
That's a tricky one.? I wonder if transmitting a beacon using a mode designed for 'rapid' QSOs is something we should even consider doing?
Thanks
David? G0MRF
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Winding Tip for 80 Mtr QCX transformer (T1)
Hi Des (again) and others
I just searched this topic and your name came up again.
I had to have 3 attempts to wind the T1 transformer.
On the first attempt, I ran out of 28swg wire to complete the winding having obviously?used generous amounts for the other inductances.
(QRP Labs - please note that a little more wire would not go amiss).
I had some 27swg and 30swg wire and decided to try the 27swg?but trying to wind 83 turns on a T50-2 toroid is no easy task and I abandoned this in favour of the 30swg.
I managed to wind the transformer with quite a bit of overlap of 30swg wire and I presume I have wired it up correctly as I am now hearing stations? reasonably well from continental Europe. Obviously, 30swg wire?is quite delicate but it?is certainly workable if one is careful.
The issue I have is with the alignment: it is starting to peak but I am only achieving a scaling factor of 5 with the plates of C1 completely closed and I now have to add some more turns.
For optimum performance,?is the target value around 9 as indicated in the manual and I am wondering whether it is easier to remove turns rather than add.
In other words, would it be better to add 10 turns rather than 5 turns as suggested in the manual ?
Again input from you or any other would be most welcome.
73s
Robin
G4DNP
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Re: Low Power fix on QCX 80 and a sugestion for a possible addition to QCX test gear to measure inductance.
Des and Alan
I have just subscribed to the group and I wonder?if?either of you can help an old timer who has?only returned to amateur radio in the last couple of years after 30 years of no activity.
In fact, the last transceiver I built was a Heathkit HW8 which still works?- ?Hi Hi.
I have just completed building the QCX 80 and it worked first time thanks to the excellent Assembly Guide Manual.
In my opinion, I also have a slightly lower power output?than expected.
Using the online power meter, I ?have 5.2 watts on the drains of Q1, Q2 and Q3 (with both 9.5 and 11.3 V power source) and the following measurement across L1:
L1/L2 Junction = 3.3 watts (11.3V)? and?2.3 watts (9.5V)
L1/power output BNC socket = 2.0 watts (11.3V) and 1.5 watts (9.5V)
I understand these power measurements are not necessarily accurate values but serve for the purpose of comparison.
I note the possible removal of turns from the inductances L1, L2, L3 and L4 but before embarking on this I would be interested to know which inductance did you find was the most critical and turns removed.
I am fully aware that inductance values?can vary according to core material, tightness of turns, closeness of turns etc but would greatly appreciate your input as a quick fix until I can set myself up with the inductance measuring circuit.
Kind regards and 73s
Robin
G4DNP
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Re: U3S drift/chirp - again!
Thanks for the replies Bob and Daniel.
I've changed the step time as suggested by Bob and it has significantly reduced the 'tail' on 28MHz QRSS transmissions. You both gave other useful info for me to consider.
Thanks again,
73,
Ian, G4JQT
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Hi Ian,
I built a 10m LPF kit for my U3S yesterday and ran it up on 28.000.089 FSKCW QRSS.??? With long calibration parameters, a similar 'power-on tail' and almost the same -20 Hz frequency error occurred, along with slow drift during the whole transmission just as
the grabber screen shot shows on your U3S.??? It seems that a long calibration time (like 20 240 as in your first posting) causes the standard synth module to cool down too much during the calibration period resulting in the calibration inaccuracy and then
frequency drift when it starts up/warms up again.??? Far better results were obtained with short calibration parameters like "Step Time" = 20 020 (along with Park Mode parameters = 2 150.000.000 to keep the Si5351a 'busy and warm' until the start of the next
transmission) ... so, despite what the U3S operating instructions say regarding calibration time, at 28 MHz it seems that "less is more"!??? After a couple of transmissions with those settings my U3S had settled to almost drift free FSKCW at .089 (see below).?????????
Perhaps try a "Step Time" = 10 020 which should provide a calibration accuracy of 1 Hz with up to 20Hz of frequency correction at 28 MHz which should be enough to keep a U3S on the display frequency in a stable temperature environment.
FWIW, one of my standard Si5351a synth boards had a bad reference xtal which caused 'jittery/wobbly' FSK tones and a calibration error no matter what the cal settings.????????? I also have a QRP-Labs OCXO/Si5351a module which performed extremely well keeping
the U3S right on frequency with no drift regards of the calibration time length.?????? While it can be done manually, the QLG-1 GPS makes initial U3S calibration easier with the OCXO synth, but after the Ref Frq parameters in the U3S are set to match the particular
OCXO, it should stay on frequency.??? In the end, the GPS is useful to keep the U3S clock accurate, but perhaps that is not so important for QRSS?
73, Bob??? ZL1RS
On 5/12/2017 5:43 AM, ian liston-smith wrote:
Right, had my U3S have 6 minutes calibration between transmissions over night. Still the frequency is 20Hz low when frequency display is reading 28.000.890 and still has the 20Hz power-on 'tail'. Chris's grabber in not 20 Hz out.
I'm running out of options here. Do I assume there is something really wrong and chuck in the towel for 10m QRSS? I don't think there's anything left to adjust.
Is it worth getting the???OCXO/Si5351A synthesizer module kit? Is that still frequency stabilised by the
QLG1 GPS receiver module kit or is that not necessary?
Was having a lot of fun with the U3S, but maybe mine is starting to fail...
73,
Ian, G4JQT
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QCX 20m - Almost done... can't wait
Greetings all; ? ? Well I completed my QCX 20m last evening.? I have had my share of boneheaded mishaps which I take full credit for.? Initially when I was installing the glass diodes I broke one.? I manage to pillage one from a failed QRP project.? Last night when I was installing the volume pot I applied a bit too much pressure on it and cracked the board in the pot.? Net result I have no volume out.? I was able to jumper the leads on the pot to discover I am getting plenty of audio.? I hope to salvage the pot and to get the rig on-line this evening.? I may have to wait until the weekend do get to operate during the day when 20m will do better with propagation.
Hopefully these pictures come through.??
Just want to thank Hans for the continue support as well as providing just a great product.? Other than my missteps it was a great build.? Can't wait to get on the air.
72/73; Kurt - W2MW
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Hi,
I second Simon's opinion: FT-8 is a highly interactive mode with seconds to interact and was never intended as a beacon mode. Beside that the QSO runs in automatic mode. No chance to implement this in the U3s. And the crocodiles are coming into the FT-8 pond, so no chance for a 200 mW signal.
73 de Hajo
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Re: U3 V3.03b no power output after connecting QLG1
rule one, remember to take your towel ;-)
db
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On Dec 6, 2017, at 2:53 AM, Alan G4ZFQ <alan4alan@...> wrote:
forgotten to add the jumper for the PA, Colin,
Rule 1)
DO NOT PANIC!
73 Alan G4ZFQ
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Hans,
?Have you looked at going to say an ESP32 device? They would certainly eliminate any constraints for a long time on memory, cpu, I/O, etc.? I don't know what price break you get on the Atmel devices and how much you could get on the ESP32.?
73, Michael
KM4OLT
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On Wed, Dec 6, 2017 at 06:24 am, James Zelazny jr wrote:
but would like to see FT8 replace JT9 for selfish reasons
Error,I meant replace Opera with FT8. Jim
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Dean,
PI4 is being used with good results and just my opinion,should replace CW beacons altogether.Not many people are aware of this mode and how useful it is.
Software is almost too simple to use -
Of course GPS is required.FT8 would be interesting if it were to replace modes not so used in the U3S now.I have tried Opera recently and found NO ONE is there anymore.I fear that FT8 will end the same way soon as another mode emerges,but would like to see FT8 replace JT9 for selfish reasons :) JT9 also pushed to the wayside so I see a use for a FT8 beacon just because everyone is there to receive it now.Just check the decrease of modes used/not used,FT8 is winning,for now.
PI4 INFO-
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That's why I asked about (and deleted) rig control... I've only seen FT8 used to make QSO's. And yes, it's not easy
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Any chance of FT8 mode being included in the U3 firmware.
Dean, This seems to be becoming a popular "QSO" mode. Is there really any interest in making it yet another beacon mode? The WSPR sub-band is the place for that. 73 Alan G4ZFQ
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Re: What are QLG LEDs telling me?
Can't remember what it said! ?I think I tore the article out of the paper for future reference if I can remember where I put it!!!
Love Dad
On Tuesday, 5 December 2017, 14:35, Daniel Ekman SA2KNG <knegge@...> wrote:
Either the IC1 is blown, or the GPS module (or both).
DMM pin 20 of the GPS module (safer to measure on R1). A periodically varying ~3.3V signal indicates a working GPS module.
If there's a varying voltage there and not on IC1 pin 8 and 11 then the IC1 has failed.
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No, no , please no. FT8 is a 'QSO' mode and letting loose FT8 beacons in the FT8 sub-band is, in my view, pointless and counter-productive and not at all in line with the ethos of the mode. I find it hard enough to make any FT8 contacts now as the sub-band on 40/20m is so crowded (however FT8 on 6m in the Sp-E season was excellent).
73 Simon G0FCU.
On 6 December 2017 at 14:01, Hans Summers <hans.summers@...> wrote: Just program a short beacon message, like JT9, JT65, etc. So a FT8 beacon.?I'm not sure how useful that is...
73 Hans G0UPL
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Just program a short beacon message, like JT9, JT65, etc. So a FT8 beacon.?I'm not sure how useful that is...
73 Hans G0UPL
On Wed, Dec 6, 2017 at 4:53 PM, Michael Lloyd <mikell@...> wrote: Wouldn't you would have to integrate rig control for the U3 into the laptop if you were going to use FT8?
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Hi Dean
I already coded FT8 in my U3, next version v3.13, last week. I have not yet had a chance to test it. v3.13 also contains JT4 and RTTY modes.?
73 Hans G0UPL
On Wed, Dec 6, 2017 at 4:48 PM, Dean Smith <g7eob1@...> wrote: I think there are two answers to this one, but i'll ask all the same!
Any chance of FT8 mode being included in the U3 firmware.
I know the room in the ATMEGA is tight!? (PI mode anybody still use it???)
I understand this mode is a quick version of JT65 (15 second slots)!
The idea behind this is that it would be possible to fit in another tx mode within a frame.
I'm sure most will have 15 seconds spare, before calibration starts?!
thoughts anybody???
Dean G7EOB
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I think there are two answers to this one, but i'll ask all the same!
Any chance of FT8 mode being included in the U3 firmware.
I know the room in the ATMEGA is tight!? (PI mode anybody still use it???)
I understand this mode is a quick version of JT65 (15 second slots)!
The idea behind this is that it would be possible to fit in another tx mode within a frame.
I'm sure most will have 15 seconds spare, before calibration starts?!
thoughts anybody???
Dean G7EOB
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Re: U3 V3.03b no power output after connecting QLG1
Alan, that should be written on the cover of a comforting book :o)
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Re: QCX firmware 1.00d release
Hi Peter
That fix for the WSPR encoding will be in the next firmware release. 1.00e.?
73 Hans G0UPL
On Wed, Dec 6, 2017 at 10:19 AM, <peter@...> wrote: Hi Hans,
does the 1.00d also contain the fix for the WSPR encoding (as described in?/g/QRPLabs/message/18134)? Or will this be included in a future release?
best 73,
Peter, HB9TVK
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Re: U3 V3.03b no power output after connecting QLG1
forgotten to add the jumper for the PA, Colin, Rule 1) DO NOT PANIC! 73 Alan G4ZFQ
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Kurt Zimmerman
Hajo Dezelski
Michael Monteith
Colin DD5CF/G1ZOS